JP5050845B2 - Test equipment and use thereof - Google Patents

Description

  The present invention relates to a test apparatus for performing a safety test of a power storage and supply device, a safety evaluation method for a power supply device using the test apparatus, and a non-aqueous electrolyte secondary battery.

Examples of power storage and supply devices include primary batteries and secondary batteries such as lithium ion batteries, nickel metal hydride batteries, and lithium batteries, capacitors such as electrolytic capacitors and electric double layer capacitors, and power generation batteries such as fuel cells. Developed and widely used industrially.
The power storage and supply device as described above generally tends to require a high capacity density and a high output density, and it is desired to store and supply power at a larger current, and is being actively developed.

  When developing a power storage and supply device, in order to evaluate its safety, the power storage and supply device is operated by heating, short-circuiting, etc., and the behavior of the power storage and supply device is shown. To be investigated. For example, a heating evaluation test that heats the power storage and supply device and intentionally causes an explosion or the like can be mentioned.

  Conventionally, the safety test of the above power storage and supply device has been performed in a discharge type booth. An example of such a test apparatus is a Li-Ion secondary battery safety evaluation test apparatus manufactured by Hosen Co., Ltd. This test apparatus has an exhaust duct, and when gas is generated in the booth during the safety evaluation test, the gas can be discharged out of the test apparatus (see Non-Patent Document 1).

Hosen Co., Ltd., Product Catalog, [online], [October 28, 2004 Search], Internet <URL: http: // www. hohsen. co. jp / jp / products / bat / 23 / index. html>

  When a safety test is performed on a power storage and supply device, exhaust gas may be generated from the power storage and supply device. For example, in the nail penetration test, overcharge test, heating test, etc., the power storage and supply device may be deliberately exploded to evaluate its safety. Exhaust gas is generated.

  However, the conventional test apparatus including the test apparatus described in Non-Patent Document 1 is configured to simply discharge the exhaust gas as described above to the outside of the test apparatus. In addition, for example, “International certification for safety of lithium-ion batteries (small batteries)” UL1642 and other certification regulations for testing power storage and supply devices, especially safety tests for power storage and supply devices, especially in sealed systems There is no description that it should be performed, and it has been generally recognized that the safety test as described above is performed in a pressure relief system in which the inside of the booth is opened to the outside.

However, along with the increase in size of power storage and supply devices, safety tests are also being performed on large power storage and supply devices, and the amount of exhaust gas generated from power storage and supply devices has increased accordingly. . When the amount of exhaust gas increases, it is desirable to treat the exhaust gas without simply ignoring the influence of the exhaust gas on the external environment and living body simply by discharging it outside the test apparatus. In addition, high power batteries and large batteries are required to ensure particularly high safety, but it is difficult to ensure safety.
The present invention was devised in view of the above problems, and an object of the present invention is to provide a test apparatus capable of performing a safety test of an electric power storage and supply device while enabling treatment of exhaust gas. Another object of the present invention is to provide a secondary battery having a high level of safety with less gas generation at the time of short circuit or destruction.

  The inventors of the present invention have made extensive studies to solve the above problems, and as a result, an exhaust gas treatment unit capable of treating exhaust gas in a test apparatus for performing a safety test of a power storage and supply device, and the exhaust gas to the exhaust gas treatment By installing an exhaust gas holding unit that temporarily holds before entering the unit, and sending the exhaust gas slowly to the exhaust gas processing unit according to the processing capacity of the exhaust gas processing unit, the safety test of the power storage and supply device is performed. I found out that I could do it safely. Moreover, it discovered that a power supply device with higher safety | security could be produced using this safety test result. The present invention has been accomplished based on these findings.

  That is, the gist of the present invention is to provide a booth having a pressure resistance for conducting a safety test of a power storage and supply device, an exhaust gas treatment unit capable of processing exhaust gas generated from the power storage and supply device, and the exhaust gas. The exhaust gas processing unit is provided with an exhaust gas transmission unit that transmits the exhaust gas according to the processing capability of the exhaust gas processing unit (Claim 1). Thereby, the safety test of the power storage and supply device can be performed while enabling the treatment of the exhaust gas. In addition, since the exhaust gas generated so as not to exceed the processing capacity of the exhaust gas processing unit can be temporarily held in the booth, the exhaust gas can be reliably rendered harmless.

At this time, in the test apparatus, the booth is preferably configured to have a pressure resistance equal to or higher than the following booth pressure resistance A. Thereby, the safety | security of a test can be improved.
In particular, the test apparatus preferably includes an inert gas replacement unit that can replace the interior of the booth with an inert gas, and the booth has a pressure resistance equal to or higher than the following booth breakdown voltage A (claim). Item 2). As a result, when the safety test is performed in an inert gas atmosphere, exhaust gas is not generated suddenly or even if the exhaust gas is temporarily held in the booth, the booth is not damaged. Safety can be further improved.
Booth pressure resistance A: The dose rate is the value obtained by multiplying the TNT dose corresponding to the total calorific value during heating of the power storage and supply device by the TNT yield, and the safety factor to the blast pressure determined by Hopkinson's third root rule. Applied pressure.

In the test apparatus, the booth is preferably configured to have a pressure resistance equal to or higher than the following booth pressure resistance B. This also increases the safety of the test.
In particular, the test apparatus preferably includes an air replacement unit that can replace the inside of the booth with air, and the booth has a pressure resistance equal to or higher than the following booth pressure resistance B (Claim 3). As a result, when the safety test is performed in an air atmosphere, the exhaust will not be generated suddenly or even if the exhaust is temporarily held in the booth, the booth will not be damaged. Can be further improved.
Booth pressure resistance B = Initial pressure × (Tb / T0) × Safety factor (However, the initial pressure represents the booth internal pressure before exhaust gas generation during the safety test, Tb represents the combustion flame temperature during the safety test, and T0 is (Represents the ambient temperature in the booth before the generation of exhaust gas during the safety test.)

Furthermore, it is preferable that the test apparatus includes a decompression unit capable of decompressing the booth to 8 kPa or less. As a result, when replacing the gas in the booth with another gas, the pressure is reduced and the gas can be replaced efficiently. It is also possible to perform a safety test under reduced pressure.
Moreover, it is preferable that this test apparatus is provided with the cooling part (cooling medium line) which reduces the temperature in this booth (Claim 5). This makes it possible to perform a safety test at low temperatures.

Further, the test apparatus preferably includes an exhaust gas sampling unit that collects the exhaust gas (Claim 6), and preferably includes an exhaust gas analysis unit that analyzes the exhaust gas collected by the exhaust gas sampling unit (Claim). 7). Thereby, composition analysis of the exhaust gas generated in the safety test can be performed.
Furthermore, it is preferable that the test apparatus includes a blast pressure sensor that measures a blast pressure of the explosion when an explosion of the power storage and supply device occurs (claim 8).

Another gist of the present invention is to perform a safety test of a power supply device using the test apparatus (claims 1 to 8), and to evaluate the safety of the power supply device based on the test result. The present invention resides in a method for evaluating the safety of a power supply device (claim 9).
The safety test in this safety evaluation method is preferably selected from a nail penetration test, an overcharge test, a heating test, an external short circuit test, a drop test, a crush test, an overdischarge test, a thermal shock test, and a vibration test. Item 10).

  According to the test apparatus of the present invention, it is possible to perform a safety test of an electric power storage and supply device while enabling treatment of exhaust gas. Moreover, according to the safety evaluation method for a power supply device of the present invention, it is possible to evaluate the safety of the power supply device using the test apparatus. In addition, according to the present invention, it is possible to provide a non-aqueous electrolyte secondary battery with less gas generation and higher safety even when the battery is broken or an internal short circuit occurs.

It is a typical block diagram showing the testing apparatus as 1st Embodiment and 2nd Embodiment of this invention. It is a correlation diagram showing the relationship between the conversion distance and the blast pressure in Hopkinson's third root rule.

Explanation of symbols

1 Booth (exhaust gas holding part)
2 Exhaust gas treatment part 3 Exhaust gas delivery line (exhaust gas delivery part)
4 Indoor gas replacement line (inert gas replacement part, air replacement part)
5 Decompression line (decompression unit)
6 Cooling line (cooling part)
7 Exhaust gas collection line (exhaust gas collection part)
11 Pressure sensor (blast pressure sensor)
21 Fluorine adsorption tower 22 Flushing tower 23 Activated carbon treatment tank 24 Blower 25, 26, 27, 31, 35, 43, 52, 71 Piping 32, 42, 53, 54, 74, 75 On-off valve 33 Switching valve 34, 41 Gas cylinder 51 , 73 Vacuum pump 72 Sample container

  Hereinafter, the present invention will be described with reference to embodiments. However, the present invention is not limited to the following embodiments, and can be arbitrarily modified without departing from the gist of the present invention.

[I. Test equipment]
[I-1. First Embodiment]
[I-1-1. Power storage and supply device]
The power storage and supply device broadly means a device capable of storing or supplying power. Specific examples of the power storage and supply device include primary batteries such as alkaline batteries and lithium batteries, secondary batteries including non-aqueous electrolyte secondary batteries such as lead acid batteries, nickel-cadmium batteries, nickel metal hydride batteries, lithium ion batteries, Examples include power generation batteries such as fuel cells, capacitors such as electrolytic capacitors, and electric double layer capacitors. These power storage and supply devices often emit exhaust gas when the safety test is performed, and the present invention makes it possible to perform the safety test while treating the exhaust gas.

[I-1-2. Exhaust gas]
The exhaust gas discharged from the power storage and supply device is mainly generated by the reaction, decomposition, or simple release of the material constituting the power storage and supply device.
For example, in the case of a lithium ion battery which is a kind of power storage and supply device, for example, vapor of organic solvent used in the electrolyte, water vapor, hydrogen, carbon monoxide, carbon dioxide, hydrogen fluoride, methane, Ethane, ethylene, propane, propylene, oxygen and the like can be generated as exhaust gas. Examples of things that are not gases but should be treated in the same way as gases because they disperse in the gas phase include electrolyte mist, fine fragments and dust of electrodes, current collectors, battery cans, etc. And solids (dust) generated as a result of thermal decomposition of. All of these are preferably treated as exhaust gas.

  It is assumed that the exhaust gas is generated mainly by the following mechanism. That is, when the power storage and supply device is exposed to a high temperature, the component is thermally decomposed, and the temperature of the power storage and supply device is further increased by the decomposition heat. As a result, a so-called thermal runaway state occurs in which exhaust gas generation due to thermal decomposition is accelerated. In this thermal runaway state, pyrolysis, reaction, etc. proceed rapidly, and the accompanying exhaust gas generation rate is extremely fast.

  Note that the reason why the power storage and supply device is exposed to a high temperature as described above is not only that the power storage and supply device is heated at a high temperature and heated as a whole, but also, for example, inside the power storage and supply device. A short circuit occurs, and the energy of the discharge that the power storage and supply device itself has and the energy of the charger / discharger connected to the power storage and supply device concentrate on the short circuit part and locally become high temperature due to Joule heat, etc. Can be mentioned.

In addition, when the power storage and supply device uses an electrolyte solution, the electrolyte solution is vaporized by heat, so that exhaust gas is also generated by the vaporization. For example, an organic solvent is usually used as an electrolytic solution for a lithium primary battery or an electric double layer capacitor, and the organic solvent is vaporized to become exhaust gas. Further, for example, a nickel metal hydride battery uses an aqueous solvent as an electrolytic solution, and in this case, hydrogen is generated as exhaust gas. In a power storage and supply device using a liquid such as an electrolytic solution, the vapor pressure increases with temperature.
Furthermore, in general, an electrode used for a power storage and supply device is generally manufactured using powder, fine particles, or the like. Therefore, these powders, particles, and the like become powder during breakage or rupture of the power storage and supply device during the thermal decomposition reaction, and are dispersed in the gas phase to become exhaust gas.

In particular, when the power storage and supply device is enlarged, the amount of its constituent members used is also increased, the specific surface area is reduced, the heat removal capability is lowered, and the temperature tends to increase. Furthermore, when the power storage and supply device is enlarged, the electric energy that the power storage and supply device itself has and the energy that is concentrated when the connected charger becomes large and a short circuit occurs increases. Regardless of the type, it is prone to thermal runaway. Therefore, when the power storage and supply device is enlarged, the amount of the generated exhaust gas tends to increase.
One of the advantages of the test apparatus of the present invention is that a safety test can be performed while processing the exhaust gas generated as described above.

[I-1-3. test]
There is no limitation on the safety test performed using the test apparatus of the present invention, and it is optional as long as the effects of the present invention are not significantly impaired. However, normally, if the safety test is performed such that exhaust gas is generated from the power storage and supply device by the safety test, the effect of the present invention that the exhaust gas can be treated can be effectively utilized. Therefore, it is preferable.

  A specific example of the safety test of such a power storage and supply device is, for example, a nail penetration test. The nail penetration test is performed by attaching a nail to a pressing means such as a hydraulic press machine and moving the nail at a predetermined speed to pierce the nail into a fixed test power storage and supply device. By inserting the nail, an internal short circuit occurs in the power storage and supply device. In the nail penetration test, the voltage, surface temperature, electrolyte leakage, smoke generation, and degree of breakage of the power storage and supply device when this internal short circuit occurs are measured.

  A specific example of the safety test is an overcharge test. In the overcharge test, the power storage and supply device for the test is continuously charged beyond the normal charge capacity. This may cause abnormal heat generation in the power storage and supply device. In the overcharge test, the voltage, current, surface temperature, electrolyte leakage, smoke generation, breakage, etc. of the power storage and supply device when this abnormal heat generation occurs are measured. In addition, when performing an overcharge test, test conditions, such as a charging current and an upper limit voltage, can be set suitably.

Furthermore, a heat test is also mentioned as a specific example of the safety test. In the heating test, a power storage / supply device for testing is exposed to a high temperature using an oven, a hot plate, or the like to heat all or part of the power storage / supply device. In the heating test, the voltage, surface temperature, electrolyte leakage, smoke generation, and degree of breakage of the power storage and supply device during heating are measured.
In addition, as a safety test of a power storage and supply device that can be performed using the test apparatus of the present invention, for example, an external short circuit test, a drop test, a crush test, an overdischarge test, a thermal shock test, Also includes vibration tests.

[I-1-4. Test equipment]
FIG. 1 is a block diagram schematically showing an outline of the test apparatus of the present embodiment. As shown in FIG. 1, the test apparatus of this embodiment includes a booth 1, an exhaust gas treatment unit 2, an exhaust gas delivery line 3 as an exhaust gas delivery unit, an indoor gas replacement line 4, and a decompression line as a decompression unit. 5, a cooling medium line 6 serving as a cooling unit, and an exhaust gas collecting line 7 serving as an exhaust gas collecting unit. In FIG. 1, the direction of the exhaust gas and the refrigerant flowing in the pipe is indicated by arrows.

[I-1-4-1. booth]
The booth 1 is a container having a space for a safety test inside. There is no restriction | limiting in the shape, It can form as arbitrary shapes, such as box shape, cylindrical shape, and spherical shape. Furthermore, the dimensions can also be set as appropriate according to the dimensions of the safety test equipment installed inside and the power storage and supply device that is the test object.

  Moreover, although the material which forms the booth 1 is also arbitrary, when airtightness, pressure | voltage resistance, durability, etc. are considered, forming with a metal is preferable. In particular, in a safety test, highly corrosive gases, liquids, solids, and the like are often scattered in the booth 1, and therefore, it is more preferable to form the material with a good antirust property. Specific examples of suitable materials include stainless steel, hastelloy, inconel and the like. Further, it is also preferable to form the booth 1 by coating or lighting a corrosion-resistant substance such as Teflon (registered trademark) for imparting corrosion resistance and forming a protective layer on an arbitrary metal surface.

Furthermore, from the viewpoint of improving the pressure resistance of the booth 1, it is also preferable to give some reinforcement to the booth 1. For example, the booth 1 may be formed by arbitrarily using a known pressure vessel, pressure door, or the like so as to increase the pressure resistance. Moreover, it can also comprise so that it may become the reinforcement structure which reinforced the circumference | surroundings of the booth 1 with reinforced concrete etc.
Moreover, it is desirable that the booth 1 has high airtightness. Specifically, it is preferable to reduce the inside of the booth 1 to the design pressure and leave it for 30 minutes, so that there is no change in the booth 1. Thereby, it is possible to prevent the atmosphere from entering the booth 1 or the exhaust gas in the booth 1 from leaking outside.

Furthermore, it is preferable that the booth 1 is provided with a door for carrying test equipment and test samples into the internal booth 1 and maintaining the test equipment. The shape of the door is arbitrary. For example, if the booth 1 is box-shaped, one of the box-shaped side surfaces may be formed as a door as it is. Moreover, the dimension of a door is arbitrary if it is a magnitude | size which is a grade which can take in and out test equipment etc. freely in the booth 1. FIG. Usually, the area of the door is preferably 0.1 m ² or more.

  Through this door, it is possible to carry in test equipment and test samples, perform maintenance, and the like. Here, the term “maintenance” refers to inspection of test equipment, inspection of booth damage, inspection of wiring defects, inspection of piping defects, replacement of test equipment, repair of test equipment, cleaning of booth 1, etc. I mean.

  Further, a door (hereinafter referred to as “small door” as appropriate) may be provided on a part of the door (hereinafter referred to as “large door” as appropriate). Large doors as described above are usually heavy and difficult to open and close. During the safety test, it is preferable to quickly open and close the door in order to maintain airtightness in the booth 1, but if the large door is heavy, it takes time to open and close. On the other hand, if the small door is provided, the small door is generally easier to open and close than the large door, so that the small door can be opened and closed quickly, and the airtightness in the booth 1 is not impaired.

The shape of the small door is arbitrary, and can be formed in an appropriate shape such as a square or a circle.
The size of the small door is also arbitrary, and can be set to an appropriate size according to the size of the power storage and supply device, the size of the parts to be taken in and out of the booth 1 through the small door, and the like. For example, the area of the small door, ^normally, or equal to 0.04m ² ~0.1m 2. When a small door is provided in the booth 1, normally, a small door is used for loading and unloading test samples into the booth 1, and a large door is used for loading and unloading test equipment and maintenance of the test equipment. Will be used. However, a single door having the functions of both a small door and a large door may be provided in the booth 1.

Furthermore, the test space provided in the booth 1 is not limited in shape and size as long as it can be isolated from the outside and has airtightness, and can be arbitrarily set according to the purpose of the test equipment and safety test. can do. For example, specific examples of the shape of the test space include a quadrangular prism shape, a cylindrical shape, and a spherical shape. Although the volume of the booth 1 is arbitrary, typically to 0.5 m ³ or more 10 m ³ or less.

Furthermore, in the booth 1, test equipment and wiring used for safety tests are usually installed. As these test equipment and wiring, it is possible to arbitrarily install an appropriate type of equipment according to the type of safety test. Specific examples of commonly used ones include test equipment such as a heater and a nail penetration test press, wiring for controlling them, and a power source for supplying power to them. In addition, when using a heater, it is preferable to use what can be heated in the temperature range of -40 degreeC-+350 degreeC.
In addition, an observation device such as a CCD camera may be installed in order to observe and record the internal state during the safety test. However, in this case, it is preferable to protect the observation apparatus with a protective case formed of SUS (stainless steel) or the like.

Moreover, it is preferable to install sensors used in the safety test in the booth 1. There is no restriction | limiting in the kind of sensors, A suitable thing can be arbitrarily used according to the objective of a safety test. For example, as shown in FIG. 1, a pressure sensor (blast pressure sensor) 11 may be provided in the booth 1. Thereby, the amount of exhaust gas generated by the safety test and the blast pressure when an explosion occurs during the safety test can be measured.
The pressure sensor 11 can be appropriately installed at an arbitrary position in the booth 1, but here, it is assumed that it is installed on the inner wall of the booth 1.

Moreover, there is no restriction | limiting in the kind of pressure sensor 11, As long as the effect of this invention is not impaired, arbitrary pressure sensors can be used. However, when evaluating the safety of a power storage and supply device based on changes in the internal pressure of the booth 1, the pressure increase speed, the maximum ultimate pressure, etc., it is usually possible to measure the pressure at a high frequency of 10 Hz or higher (that is, at a short measurement interval). It is preferable to use a pressure sensor.
In addition, when distortion arises in the wall part, bottom part, ceiling part, etc. of booth 1 according to the pressure in booth 1, the strain gauge which measures the distortion is installed, and the magnitude | size of the strain measured by it The pressure may be calculated.

Moreover, a temperature sensor is mentioned as an example of other sensors used. As the temperature sensor, a sensor that can measure the atmospheric temperature in the booth 1, the surface temperature of the power storage and supply device, the internal temperature, and the like can be appropriately used according to the type and purpose of the safety test. In particular, the temperature sensor is often used with a heater.
Furthermore, for example, when using a nail penetration test press, it is preferable to use a position sensor for controlling the nail penetration position, the nail penetration depth, and the like.

  In the test apparatus of the present invention, the exhaust gas generated from the power storage and supply device by the safety test is temporarily held before entering the exhaust gas treatment unit 2. That is, the normal exhaust gas treatment unit 2 has a predetermined limit on the processing capacity (processing speed), but in the safety test, an amount of exhaust gas that generally exceeds the processing capacity is generated. There is a possibility that the exhaust gas generated by the safety test in the part 2 cannot be completely processed. Although it is conceivable to prepare the exhaust gas treatment unit 2 having a sufficiently large treatment capacity, in this case, the equipment cost becomes very large. Therefore, in order to solve the above-described points, the test apparatus of the present embodiment is provided with an exhaust gas delivery line 3 that can send exhaust gas to the exhaust gas treatment unit 2 at a speed corresponding to the exhaust gas treatment capability of the exhaust gas treatment unit 2 and sends the exhaust gas. The previous exhaust gas is temporarily held. The exhaust gas may be held anywhere as long as it is upstream of the exhaust gas treatment unit 2. For example, a tank for holding the exhaust gas may be provided in the exhaust gas delivery unit 2. Normally, the booth 1 itself is connected to the exhaust gas holding unit. The exhaust gas is temporarily held in the booth 1.

  Here, when the booth 1 temporarily holds the exhaust gas, how long the exhaust gas is held is arbitrary according to the exhaust gas treatment capacity of the exhaust gas treatment unit 2, but is sent from the booth 1 to the exhaust gas treatment unit 2. It is desirable to keep the amount of exhaust gas according to the processing capacity of the exhaust gas processing unit 2 so that the amount of exhaust gas does not exceed the processing capacity of the exhaust gas processing unit 2. Specifically, it can be maintained for usually 20 minutes or longer, preferably 1 hour or longer, more preferably 3 hours or longer.

By the way, in order to make the booth 1 hold the exhaust gas, it is desirable to provide the booth 1 with pressure resistance according to the conditions of the safety test so that the exhaust gas can be held. Specifically, it is desirable that the pressure resistance of the booth 1 has a pressure resistance that can maintain at least a sealing property that allows gas replacement in the booth. This is because a large amount of exhaust gas may be generated depending on the conditions and types of the safety test, and therefore it is desirable to provide the booth 1 with sufficient pressure resistance to hold the exhaust gas. In this case, as will be described later, the withstand voltage that the booth 1 should have is preferably determined according to the atmosphere in the booth 1 during the safety test. Specifically, the atmosphere in the booth 1 is an inert atmosphere. It is preferable to distinguish between the case and the air atmosphere.
In the present embodiment, it is assumed that the booth 1 has a pressure resistance enough to hold the exhaust gas, and includes a pressure sensor 11 in the booth 1. Moreover, since the booth 1 has pressure resistance as described above, the booth 1 can function as an exhaust gas holding unit in the test apparatus of the present embodiment.

[I-1-4-2. Exhaust gas treatment section]
The exhaust gas treatment unit 2 treats the exhaust gas generated in the safety test (hereinafter referred to as “detoxification treatment” as appropriate) and makes it harmless even if it is discharged out of the system. As long as the detoxification treatment of the exhaust gas is possible, the specific configuration is not limited, and any configuration can be used according to the type of exhaust gas generated. In this embodiment, it is assumed that the exhaust gas treatment unit 2 includes a fluorine adsorption tower 21, a water washing tower 22, an activated carbon treatment tank 23, a blower 24, and pipes 25, 26, and 27 that connect the parts.

The fluorine adsorption tower 21 is an adsorption tower filled with a fluoride adsorbent. By passing through the fluorine adsorption tower 21, the fluoride contained in the exhaust gas can be adsorbed on the fluoride adsorbent and removed. ing. Specific examples of the fluoride removed here include, for example, hydrogen fluoride. In order to remove fluoride, a scrubber using a sodium hydroxide aqueous solution as a cleaning liquid can be used instead of (or in combination with) the fluorine adsorption tower 21.
The exhaust gas that has passed through the fluorine adsorption tower 21 is sent to the water washing tower 22 through the pipe 25.

  The washing tower 22 is for washing the exhaust gas, and by passing through the washing tower 22, the solid phase components in the exhaust gas such as electrode material powder are washed and removed, or the components that are easily dissolved in water are dissolved and removed. You can do it. The exhaust gas that has passed through the water washing tower 22 is sent to the activated carbon treatment tank 23 through the pipe 26.

  The activated carbon treatment tank 23 is a container filled with activated carbon, and by passing through the activated carbon treatment tank 23, organic gas or the like can be adsorbed and removed by the activated carbon. The exhaust gas that has passed through the activated carbon treatment tank 23 is sent to the blower 24 through the pipe 27.

  The blower 24 is for discharging the sent exhaust gas out of the system. The exhaust gas discharged from the blower 24 is processed in the fluorine adsorption tower 21, the water washing tower 22, and the activated carbon treatment tank 23, and therefore does not contain any components that would be discharged out of the system. It can suppress that the exhaust gas generated by the property test is harmful to the environment.

  The exhaust gas treatment speed of the exhaust gas treatment unit 2 is not limited. Even if exhaust gas exceeding the limit of the processing speed is generated in the safety test, the exhaust gas can be temporarily held using the booth 1 as the exhaust gas holding unit, so that the exhaust gas is discharged at a speed according to the processing capacity of the exhaust gas processing unit 2. This is because it can be sent to the exhaust gas treatment unit 2.

  In addition, there is no restriction on how much harmful substances in the exhaust gas are removed by the detoxification treatment, but the concentration of harmful substances in the exhaust gas discharged from the exhaust gas treatment unit 2 to the outside of the system is usually 5% by weight or less. It is desirable that the content be 2% by weight or less, more preferably 1% by weight or less. In addition, the harmful substance said here points out a fluorine-containing compound, hydrocarbon, a phosphorus-containing compound, dust etc., for example.

[I-1-4-3-3. Exhaust gas delivery line]
The exhaust gas delivery line 3 is for sending exhaust gas from the booth 1 to the exhaust gas treatment unit 2 according to the processing capability of the exhaust gas treatment unit 2. Specifically, the exhaust gas is sent from the booth 1 to the exhaust gas processing unit 2 while adjusting the flow rate of the exhaust gas so as not to exceed the limit of the processing speed of the exhaust gas processing unit 2. In the present embodiment, the exhaust gas treatment line 3 includes a pipe 31 and an on-off valve 32.
Specifically, the booth 1 and the fluorine adsorption tower 21 of the exhaust gas treatment unit 2 are connected by a pipe 31, and when the on-off valve 32 is opened, both communicate with each other to send the exhaust gas in the booth 1 to the fluorine adsorption tower 21. The above delivery can be stopped by closing the on-off valve 32.

  In addition, when exhaust gas is generated in the booth 1, the booth 1 is usually at a higher pressure than the exhaust gas treatment unit 2 due to the generation of exhaust gas. It is sent to the processing unit 2. Further, since the pipe 31 is sucked by the blower 24, the exhaust gas in the booth 1 is more reliably sent to the exhaust gas treatment unit 2 through the pipe 31.

  Furthermore, it is possible to prevent the exhaust gas in the booth 1 from being discharged from the door to the outside by using the suction of the blower 24. That is, for example, if the on-off valve 32 is opened during opening and closing of the door, the suction of the blower 24 causes the inside of the pipe 31 to have a negative pressure than the inside of the booth 1, and thus the pipe 31 sucks the gas in the booth 1. Therefore, the pressure in the booth 1 becomes lower than the external pressure of the test apparatus, and therefore, it is possible to prevent the gas in the booth 1 such as exhaust gas from leaking out of the test apparatus.

  Further, the exhaust gas delivery line 3 is provided with a flow rate adjusting means for adjusting the flow rate of the exhaust gas to be delivered according to the processing capacity of the exhaust gas treatment unit 2, and the exhaust gas at an inflow rate exceeding the limit value of the exhaust gas treatment rate of the exhaust gas treatment unit 2. Is prevented from flowing into the exhaust gas treatment unit 2. Although how to adjust is arbitrary, it is preferable to provide a squeeze, for example. As a specific example, the pipe 31 itself can be made to function as a squeeze by setting the inner diameter of the pipe 31 to be equal to or less than a predetermined value and allowing only an exhaust gas having a flow rate corresponding to the processing capacity of the exhaust gas processing unit 2 to flow. As a result, the inflow rate of the exhaust gas flowing into the exhaust gas treatment unit 2 is maintained so as not to exceed the limit of the exhaust gas treatment rate of the exhaust gas treatment unit 2, so that exhaust gas that cannot be processed by the exhaust gas treatment unit 2 is rendered harmless. Without being released outside the system.

  For example, as a method for adjusting the flow rate of the exhaust gas, a throttle valve may be provided in addition to adjusting the diameter of the pipe 31. In this case as well, the degree of throttling of the throttle valve is arbitrary, but it is preferable that the flow rate of the exhaust gas be within the range of the exhaust gas processing speed of the exhaust gas processing unit 2 by the flow rate adjusting function of the throttle valve. This also ensures that the exhaust gas flow rate does not exceed the limit of the processing capacity of the exhaust gas processing unit 2.

Furthermore, the amount of the exhaust gas that the exhaust gas sending unit 3 sends to the exhaust gas processing unit 2 per unit time is arbitrary as long as the processing capacity of the exhaust gas processing unit 2 is not exceeded. However, from the viewpoint of surely detoxifying the exhaust gas, the exhaust gas is usually 90% or less, preferably 80% or less, more preferably 50% or less with respect to the limit value of the processing speed of the exhaust gas treatment unit 2. It is desirable to adjust the flow rate of the exhaust gas so as to flow into the treatment 2.
In addition, a flow sensor and a safety valve that detect the flow rate of the exhaust gas are provided in the pipe 31, and when the exhaust gas flow rate exceeding the above range is detected by the flow sensor, the safety valve may be closed or the flow path may be throttled. preferable.

Further, some flow control means may be provided in order to further enhance the safety during the test. For example, the exhaust gas delivery line 3 is provided with an open / close valve that repeatedly opens and closes every predetermined time, and the flow rate control of the exhaust gas is performed by adjusting the ratio between the open time and the open time of the open / close valve. Also good.
Furthermore, a flow rate sensor for detecting the flow rate of the exhaust gas flowing through the exhaust gas delivery line 3 and a throttle valve for reducing the opening when the flow rate of the exhaust gas detected by the flow rate sensor exceeds a specific value are provided. You may make it perform the flow control of waste gas. At this time, if the specific value is set to be equal to or less than the limit value of the exhaust gas treatment rate of the exhaust gas treatment unit 2, the inflow rate of the exhaust gas to the exhaust gas treatment unit 2 can be prevented from exceeding the limit value.

By adjusting the flow rate of the exhaust gas in the exhaust gas delivery line 3 in this way, the exhaust gas before being sent out by the exhaust gas sending unit 3 is held in the booth 1. However, even in this case, since the booth 1 has sufficient pressure resistance as described above, the booth 1 may be damaged even if the exhaust gas before being sent to the exhaust gas treatment unit 2 is temporarily held. There is no.
In the present embodiment, it is assumed that the exhaust gas delivery line 3 is formed using a pipe 31 having an inner diameter corresponding to the exhaust gas treatment capacity of the exhaust gas treatment unit 2. Further, in the present embodiment, the on-off valve 32 functions as a throttle valve capable of adjusting the throttle amount (valve opening degree), and exhaust gas can also be adjusted by adjusting the throttle amount of the on-off valve 32. It is assumed that the inflow speed of the exhaust gas flowing into the processing unit 2 can be adjusted. However, the flow rate of the exhaust gas can be controlled by only one of the pipe 31 and the on-off valve 32.

Furthermore, in the present embodiment, a switching valve 33 is provided immediately before the exhaust gas treatment unit 2 of the pipe 31, and by switching the switching valve 33, a flow path connecting the booth 1 and the exhaust gas treatment unit 2, and a gas cylinder 34 and the exhaust gas treatment unit 2 can be connected to switch the flow path for supplying the inert gas to the exhaust gas treatment unit 2.
Specifically, a gas cylinder 34 in which an inert gas such as nitrogen gas is stored is connected to the switching valve 33 by a pipe 35. Therefore, by switching the switching valve 33 and supplying the inert gas from the gas cylinder 34 to the exhaust gas treatment unit 2, oxygen present in the system of the exhaust gas treatment unit 2 is expelled and the exhaust gas treatment unit 2 is introduced when the exhaust gas is introduced. The oxygen concentration inside does not enter the explosion range.

[I-1-4-4. Indoor gas replacement line]
The indoor gas replacement line 4 is for replacing the interior of the booth 1 with an inert gas. Here, the indoor gas replacement line 4 is configured by connecting a gas cylinder 41 storing an inert gas to the booth 1 through a pipe 43 having an on-off valve 42. Thereby, when the on-off valve 42 is opened, the inert gas in the gas cylinder 41 is sent to the booth 1, and the atmosphere in the booth 1 can be replaced with the inert gas. That is, the inert gas replacement line 4 of the present embodiment functions as an inert gas replacement unit.

  As the inert gas, any kind of gas having low reactivity with exhaust gas can be used. Specific examples include noble gases such as argon and helium, nitrogen, and the like. In particular, when a power storage / supply device containing lithium is used in the composition, it is preferable to use a rare gas as the inert gas because lithium may react with nitrogen. In addition, these inert gas may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

Here, the inside of the booth 1 is replaced with an inert gas because the exhaust gas discharged from the power storage and supply device burns or explodes due to oxygen in the air in the booth 1, thereby enabling composition analysis of the exhaust gas. This is to prevent the booth 1 from being lost or being destroyed due to the internal pressure of the booth 1 exceeding the pressure of the booth 1. Therefore, the replacement with the inert gas in the booth 1 is preferably performed when it is desired to analyze the composition of the exhaust gas.
In the present embodiment, it is assumed that the indoor gas replacement line 4 is configured such that a rare gas is used as the inert gas.

[I-1-4-5. Pressure reduction line]
The depressurization line 5 is for depressurizing the inside of the booth 1, and includes a vacuum pump 51, a pipe 52 connecting the vacuum pump 51 to the booth 1 and the exhaust gas delivery line 3, and before and after the vacuum pump 51 of the pipe 52 (that is, , Upstream and downstream) on / off valves 53 and 54, respectively. Therefore, by opening the on-off valves 53 and 54, the booth 1 and the vacuum pump 51 communicate with each other to depressurize the inside of the booth 1, and the gas drawn from the booth 1 to the vacuum pump 51 passes through the exhaust gas delivery line 3. The exhaust gas is sent to the exhaust gas treatment unit 2.

  Here, the decompression in the booth 1 is performed because the inert gas is supplied from the gas cylinder 41 in a state where the inside of the booth 1 is decompressed when the atmosphere in the booth 1 is replaced by the indoor gas replacement line 4. By doing so, the replacement can be performed efficiently. Further, even if exhaust gas remains in the booth 1 when the atmosphere in the booth 1 is replaced, the exhaust gas concentration in the booth 1 can be reduced by reducing the pressure in the booth 1 as described above. Even if the atmosphere and the exhaust gas are mixed, it is possible to suppress the exhaust gas concentration from entering the explosion range.

In addition, the amount of exhaust can be controlled by the decompression line 5 in order to effectively treat harmful gases and vapors containing fluoride. That is, by adjusting the output of the vacuum pump 51 and the opening degree of the on-off valves 53 and 54, the amount of exhaust gas sent to the exhaust gas treatment unit 2 can be controlled using the vacuum pump 51.
Furthermore, by providing the decompression line 5, it is possible to enable a safety test under reduced pressure.
Note that the decompression line 5 can be used not only to decompress the inside of the booth 1 but also to send the exhaust gas in the booth 1 to the exhaust gas treatment unit 2 through the decompression line 5.

Further, when the inside of the booth 1 is decompressed using the decompression line 5, the amount of decompression can be arbitrarily determined as long as the decompression can be performed more than the external pressure (usually atmospheric pressure) of the test apparatus. It is preferable that the pressure can be reduced to the following.
Also in this embodiment, it is assumed that the pressure in the booth 1 can be reduced to 8 kPa or less using the pressure reducing line 5.

[I-1-4-6. Coolant line]
In order to adjust the temperature in the booth 1, the test apparatus is preferably provided with temperature adjusting means. Usually, a heater is often used as a test equipment in a safety test of a power storage and supply device. Therefore, when temperature adjustment is to be performed, a cooling means for forcibly lowering the temperature raised by the heater should be provided. You can do it. In the present embodiment, a cooling medium line 6 is provided in the booth 1 so that the temperature in the booth 1 can be adjusted.

  The cooling medium line 6 is a pipe through which a refrigerant flows. The low temperature refrigerant flows through the cooling medium line 6 so that the temperature in the booth 1 can be lowered. In addition, there is no restriction | limiting in a refrigerant | coolant, As long as the effect of this invention is not impaired remarkably, arbitrary things can be used.

In addition to lowering the atmospheric temperature of the booth 1, a predetermined position in the booth 1 may be cooled. For example, when cooling a box or a base in which an electric power storage and supply device in the booth 1 is installed, a cooling medium line 6 is provided so that the box or the base can be cooled, and the electric power is stored in the box or the base. It is also possible to install a supply device and perform a safety test.
In the present embodiment, it is assumed that the coolant line 6 is provided so as to lower the ambient temperature in the booth 1.

[I-1-4-7. Exhaust gas collection line]
The exhaust gas collection line 7 is for collecting the exhaust gas generated by the safety test. The exhaust gas collection line 7 collects the exhaust gas before being processed by the exhaust gas processing unit 2 and analyzes the separately collected exhaust gas, thereby enabling detailed analysis of the power storage and supply device.

  In the present embodiment, the exhaust gas collection line 7 includes a pipe 71 branched from the exhaust gas delivery line 3, and in this pipe 71, a sample container 72 for collecting exhaust gas and an exhaust gas to be extracted from the exhaust gas delivery line 3. Vacuum pump 73 and on-off valves 74 and 75 provided before and after the sample container 72, respectively. The sample container 72 can be attached to and detached from the pipe 71. Therefore, when collecting the exhaust gas, first, the on-off valve 74 upstream of the sample container 72 is closed, the downstream on-off valve 75 is opened, and the vacuum pump 73 is operated to decompress the sample container 72. Next, the downstream on-off valve 75 is closed, the upstream on-off valve 74 is opened, and the exhaust gas is taken into the sample container 72 from the exhaust gas delivery line 3. By repeating this once or twice or more to fill the sample container 72 with the exhaust gas, the exhaust gas can be collected in the sample container 72.

The exhaust gas thus collected is subjected to analysis such as composition analysis, toxicity test, and flammability test as appropriate. There is no limitation on the method of analysis and the analysis apparatus to be used, and the analysis may be arbitrarily performed according to the purpose of the safety test.
Examples of analyzers include gas composition analyzers such as gas chromatographs, liquid chromatographs, ion chromatographs, and combustion test apparatuses described in ISO-10156-1996. In addition, the said apparatus for a combustion test is an analysis method which sparks with an electrode with respect to the mixture of the combustible gas and air with which the inside of the combustion cylinder was filled, and confirms flame propagation.

[I-1-5. how to use]
Since the test apparatus of the present embodiment is configured as described above, when using the above-described test apparatus, first, the power storage and supply device that is the subject of the safety test is installed in the booth 1. Initially, the on-off valves 32, 42, 53, 54, 74, and 75 are closed, and the switching valve 33 communicates the booth 1 with the exhaust gas treatment unit 2.

  After installing the power storage and supply device, the door of the booth 1 is closed and the inside of the booth 1 is decompressed by the decompression line 5. Specifically, the on-off valves 53 and 54 are opened and the vacuum pump 51 is operated to depressurize the booth 1. Usually, the pressure in the booth 1 may be reduced so as to be 20 kPa. Further, the pressure in the booth 1 may be detected by the pressure sensor 11. Thereby, the inside of booth 1 is decompressed.

  After decompression, decompression in the booth 1 by the decompression line 5 is stopped, and the atmosphere in the booth 1 is replaced from the indoor gas supply line 4. Specifically, the on-off valves 53 and 54 are closed, the on-off valve 42 is opened, and the inert gas in the gas cylinder 41 is supplied into the booth 1 to make the atmosphere in the booth 1 an inert gas atmosphere. At this time, it is preferable to adjust the gas supply amount from the gas cylinder 41 while detecting the pressure in the booth 1 with the pressure sensor 11 so that the pressure is appropriate for the safety test. Thereby, the atmosphere in the booth 1 is replaced with the inert gas.

  If the explosion of the exhaust gas in the booth 1 is only to be suppressed, it is sufficient to perform the decompression and atmosphere replacement in the booth 1 only once. However, when it is desired to accurately measure the composition of the exhaust gas, The decompression and atmosphere replacement in the booth 1 are usually performed twice or more, preferably six times or more. Thereby, the oxygen concentration in the booth 1 can be made sufficiently low (for example, 50 ppm or less), and the composition of the exhaust gas can be prevented from changing due to the reaction of the exhaust gas with the atmospheric gas. Also, if the exhaust gas burns or explodes outside the power storage and supply device, the amount of heat generated inside the power storage and supply device may not be detected well, and safety tests may not be performed accurately. By suppressing the explosion, the above-mentioned fear can be eliminated.

Further, after replacing the atmosphere in the booth 1, the switching valve 33 is switched to supply the inert gas from the gas cylinder 34 to the exhaust gas treatment unit 2 as described above, and the oxygen present in the system of the exhaust gas treatment unit 2 is changed. Evict it.
Moreover, the temperature in the booth 1 is adjusted using the cooling medium line 6 and the heater (not shown) in the booth 1. After the adjustment, the temperature adjustment by the coolant line 6 or the heater is stopped.

  After the above preparations are completed, a safety test such as a nail penetration test is performed in the booth 1 with the on-off valves 32, 42, 53, 74 closed and the booth 1 sealed, and the test equipment in the booth 1 The necessary data is measured using sensors. At this time, exhaust gas is generated from the power storage and supply device by a safety test. However, in the test apparatus of this embodiment, since the booth 1 has sufficient airtightness and pressure resistance, the generated exhaust gas is held in the booth 1 and is not released out of the system. The pressure sensor 11 detects the blast pressure when exhaust gas is generated, and this can also be used for analysis.

  After the exhaust gas is generated, the exhaust gas is collected by the exhaust gas collection line 7. Specifically, as described above, the open / close valves 74 and 75 are alternately opened and closed to depressurize the sample container 72, and the exhaust gas is collected in the sample container 72. The sampled gas 72 can be removed from the collected exhaust gas, and the internal exhaust gas can be analyzed with an analytical instrument or the like. After the exhaust gas is collected, the on-off valves 74 and 75 are closed.

After collecting the exhaust gas, the on-off valve 32 is opened while adjusting the valve opening, and the switching valve 33 is switched so that the booth 1 and the exhaust gas treatment unit 2 communicate with each other. To send. At this time, the pipe 31 is formed so as to function as a so-called squeeze, as described above, so that the flow rate of the exhaust gas sent from the exhaust gas delivery line 3 can be adjusted according to the processing capacity of the exhaust gas treatment unit 2. Since the exhaust gas also functions as a throttle valve, the exhaust gas can be temporarily held in the booth 1, so that the exhaust gas flowing into the exhaust gas treatment unit 2 is surely subjected to the detoxification process. become. Specifically, an amount of exhaust gas in a range not exceeding the treatment capacity of each of the fluorine adsorption tower 21, the water washing tower 22 and the activated carbon treatment tank 23 is sent to the exhaust gas treatment unit 2, and the fluorine adsorption tower 21, the water washing tower 22 and the activated carbon treatment are treated. Processing is carried out in order in the tank 23 to render it harmless. The harmless exhaust gas is discharged from the blower 24 to the outside of the system.
As described above, the safety test using the test apparatus of the present embodiment is performed.

[I-1-6. effect]
As described above, by using the test apparatus according to the present embodiment, it is possible to perform a safety test of an electric power storage and supply device while enabling treatment of exhaust gas. Further, when safety tests such as a nail penetration test, an overcharge test, and a heating test are performed on the power storage and supply device, a large amount of exhaust gas is rapidly generated. However, in the test apparatus of this embodiment, the gas delivery line 3 In order to adjust the flow rate of the exhaust gas sent according to the processing capacity of the exhaust gas processing unit 2, the exhaust gas is temporarily held before the exhaust gas flows into the exhaust gas processing unit 2, and the exhaust gas processing unit 2 according to the processing capacity The exhaust gas can be flowed into. Therefore, there is no risk that exhaust gas exceeding the processing capacity will flow into the exhaust gas treatment unit 2 and the exhaust gas detoxification process cannot be performed, and a safety test can be performed safely. In addition, power storage and supply devices that emit a large amount of exhaust gas, such as large batteries, are likely to cause difficulties in exhaust gas treatment using conventional techniques, so the advantages of using the above test device Is big.

  Furthermore, since the test apparatus of the present embodiment is configured so that the booth 1 has pressure resistance, it is possible to reliably hold the exhaust gas in the booth 1. Furthermore, because the booth 1 has pressure resistance, exhaust gas is suddenly generated when the safety test is performed in an inert gas atmosphere, or the exhaust gas is temporarily held in the booth 1. Even so, the booth 1 is not damaged, and the safety of the test can be further improved.

Furthermore, since the test apparatus according to the present embodiment includes the decompression line 5, the gas can be efficiently replaced by reducing the pressure when the gas in the booth 1 is replaced with another gas. It is also possible to perform a safety test under reduced pressure.
Furthermore, since the test apparatus of the present embodiment includes the cooling line 6 that lowers the temperature in the booth 1, the temperature can be appropriately adjusted, and a safety test can be performed at a low temperature. It becomes possible.

In addition, since the test apparatus of the present embodiment includes the exhaust gas collection line 7 that collects exhaust gas, various analyzes of the exhaust gas generated in the safety test can be performed.
Furthermore, since the test apparatus of the present embodiment includes the pressure sensor 11, it is also possible to measure the blast pressure of an explosion that occurs due to the generation of exhaust gas during a safety test.

[I-2. Second Embodiment]
The test apparatus according to the second embodiment of the present invention is the same as that of the first embodiment except that the booth 1 has a pressure resistance higher than the booth pressure A.

Therefore, also in the present embodiment, the power storage and supply device, the exhaust gas, and the safety test are the same as in the first embodiment.
As for the test apparatus, as shown in FIG. 1, the exhaust gas treatment unit 2, the exhaust gas delivery line 3, the indoor gas replacement line 4, the decompression line 5, the coolant line 6, and the exhaust gas collection line 7 are each in the first embodiment. It is the same.

Further, the booth 1 is the same as that of the first embodiment except that the booth breakdown voltage is equal to or higher than the booth breakdown voltage A.
That is, in this embodiment as well, as in the first embodiment, the exhaust gas delivery line 3 sends exhaust gas according to the processing capacity of the exhaust gas treatment unit 2, so that the exhaust gas is temporarily sent to the booth 1. Thus, the exhaust gas does not flow into the exhaust gas processing unit 2 at an inflow rate exceeding the limit value of the exhaust gas processing rate of the exhaust gas processing unit 2.

Also in the present embodiment, the safety test is performed in an inert gas atmosphere. For this reason, the booth 1 is also provided with the pressure | voltage resistance according to it.
Specifically, as in the present embodiment, when the atmosphere in the booth 1 can be replaced with an inert gas in the indoor gas replacement line 4, the safety test is performed with the inside of the booth 1 as an inert atmosphere. In this case, the booth 1 is preferably configured to have a pressure resistance equal to or higher than the following booth pressure resistance A.
Booth pressure resistance A: The dose rate is the value obtained by multiplying the TNT dose corresponding to the total calorific value during heating of the power storage and supply device by the TNT yield, and the safety factor to the blast pressure determined by Hopkinson's third root rule. Applied pressure.

  In general, the relationship between the blast pressure using an explosive as a bomb source and the distance from the bomb source is based on Hopkinson's third root rule for the blast pressure and the conversion distance in a wide range as a scale rule. This Hopkinson's third root rule indicates that the blast pressure of the explosion generated by the explosion is the same at a conversion distance, that is, “distance from the center of explosive divided by the third root of the amount of explosive dose”. In particular, it is known that the reliability is high when trinitrotoluene (hereinafter referred to as “TNT” as appropriate) is used as an explosive.

  When determining the booth pressure resistance A, the Hopkinson's third root rule, which is a scaling rule based on the conversion distance using the TNT dose, is used to determine the strength of the blast pressure using the power storage and supply device as the explosion source. The pressure value is calculated by multiplying this by the safety factor. At this time, the dose used for calculating the conversion distance (hereinafter referred to as “converted dose” as appropriate) is the TNT yield with respect to the TNT dose generated in the explosion, which is equivalent to the amount of heat generated in the gas explosion. Use the value multiplied by.

  The TNT yield is a measure of the intensity of explosion, and the TNT yield increases when a gas that is easily detonated is generated as exhaust gas. Therefore, when configuring a test apparatus that can cope with a severe explosion that may occur in a safety test regardless of the type of exhaust gas, the TNT yield used for calculating the booth pressure resistance A is usually 0.01% or more, preferably Is preferably 0.1% or more, more preferably 1% or more, and usually 20% or less, preferably 10 or less, more preferably 5% or less.

  The specific method for obtaining the TNT yield is arbitrary, but can be obtained, for example, by measuring the ratio of the actual measurement value to the theoretical value as follows. That is, an experiment in which a power storage and supply device similar to the test sample is actually pyrolyzed or exploded (hereinafter referred to as “measurement experiment” as appropriate) is performed, and the pressure at a certain distance from the test sample is measured. The mass of TNT explosive that generates the same pressure as the maximum value at the time of explosion (hereinafter referred to as “TNT equivalent” as appropriate) is obtained. This TNT equivalent, “the amount of TNT that is generated in the explosion, is equivalent to the total amount of heat that could be generated during the measurement experiment, such as thermal decomposition of the test sample, rupture, explosion, etc. TNT yield can be determined from the ratio (usually percentage) to “ The distance for measuring the pressure in the measurement experiment is arbitrary, and an appropriate distance that can be easily measured can be set as appropriate. For example, a measurement experiment may be performed in which a distance of 1 meter from the center of pyrolysis or explosion is determined as a measurement position, and a pressure transition at the measurement position is evaluated. Further, the measurement experiment may be performed in an airtight container or an open system.

  The safety factor is a value representing the degree of certainty that the booth 1 is safe. It can be said that the larger the value, the safer the booth 1 is. This safety value is usually 1 or more, usually 2 or less, preferably 5 or less.

  Specifically, the booth breakdown voltage A can be obtained as follows. That is, (1) the total calorific value generated from the power storage and supply device in the safety test is obtained, (2) the TNT dosage corresponding to the total calorific value is specified, and (3) the TNT dosage is included in this TNT dosage. Multiply the rate to calculate the equivalent dose. (4) Separately, the distance from the power storage and supply device to the target portion of the inner wall of the booth 1 is obtained from the dimensions of the booth 1 and the like. (5) Then, the distance from the power storage and supply device to the target part of the inner wall of the booth 1 is divided by the third root of the converted dose to obtain the converted distance. (6) Further, the corresponding blast pressure is specified from the conversion distance obtained as described above. (7) Finally, the booth pressure resistance A is calculated by multiplying the blast pressure by the safety factor.

Hereinafter, a specific example is shown and the calculation method of the booth pressure | voltage resistant A is demonstrated.
(1) Estimation of total heat generation amount When calculating the booth withstand pressure A, the total heat generation amount generated from the power storage and supply device in the safety test is obtained. At this time, a literature value or an assumed value may be used as the total calorific value, but in order to increase the reliability of the booth breakdown voltage A, it is preferable to use an experimental value of the total calorific value obtained experimentally.

  The experimental method for obtaining the total calorific value is arbitrary. For example, an experiment may be performed using a test device having the same configuration as the power storage and supply device that is the subject of the safety test, and the total heat generation amount may be estimated. However, in order to simplify the operation, a test device with the same composition and components as the power storage and supply device and different dimensions is prepared, and the amount of heat generated per unit volume is tested using this test device. It is preferable to calculate the total calorific value by multiplying the obtained calorific value per unit volume by the volume of the power storage and supply device. In the description of how to determine the total calorific value, the power storage and supply device used in the experiment for determining the total calorific value is referred to as a “test device” and is distinguished from the power storage and supply device used in the safety test. .

  In this example, a description will be given on the assumption that a heating test is actually performed on the test device, thereby obtaining the total calorific value. When determining the total calorific value by the heating test, the capacity of the power storage and supply device used as the test device is preferably about 0.3 ampere hours (Ah) to 2 Ah. This is because the size of the power storage and supply device is neither too small nor too large, so that the accuracy of evaluating the heat generation rate can be improved and the safety can be improved.

  Further, in the safety test, the safety evaluation of the power storage and supply device having a larger capacity than the test device is often performed. Therefore, usually, as described above, the amount of heat per unit volume is obtained using a test device having a size different from that of the power storage and supply device used for the safety test, and the power storage and supply used for the actual safety test is obtained. The total calorific value is obtained by multiplying the volume according to the dimensions of the device. Therefore, also in this example, components such as electrodes and electrolytes of the test device used in the heating test are assumed to be the same as those of the power storage and supply device actually used in the safety test.

The heating test conditions may be arbitrarily set according to the assumed safety test conditions. As an example of specific conditions, for example, heating is performed by raising the temperature from normal temperature to about 200 ° C. to about 300 ° C., and the rate of temperature increase is usually 1 K / min to 2 K / min.
Furthermore, although the apparatus used for a heating is also arbitrary, normally an oven is used. In this case, specifically, the test device is installed in the oven, and the surface temperature and the oven atmosphere temperature are measured while the temperature inside the oven is raised from room temperature. There is no restriction | limiting in the oven used at this time, Although arbitrary ovens can be used, what can set up a temperature increase rate (it is programmable) is preferable.

  In addition, during the heating test, the time transitions of the temperature of the test device itself and the ambient temperature of the test device are measured. Either the surface temperature or the internal temperature may be adopted as the temperature of the test device itself, and the temperature at which measurement is easier can be adopted as appropriate. In this example, the case where the surface temperature is used as the temperature of the test device itself will be described, but the same can be done when the internal temperature is adopted as the temperature of the test device itself.

After the heating test, the heat generation rate of the test device is obtained from the measured temperature transition, and the heat generation rate is integrated over time to obtain the total heat generation amount from the test device.
The heat generation rate is calculated using the time change of the temperature of the test device itself obtained by the heating test, that is, here, the time change of the surface temperature of the test device. Specifically, first, the heat transfer coefficient of the measured test device is obtained using the surface temperature and the ambient temperature of the test device. The heat transfer coefficient is a parameter for evaluating the heat exchange rate between the surface of the test device and the outside of the test device, and is a coefficient used for converting the surface temperature into the heat generation rate.

ただし、式１において、各記号が表わす値は、次の通りである。
ρ ： 試験用デバイスの密度
Ｃｐ ： 試験用デバイスの比熱
Ｔ ： 試験用デバイスの温度
ｔ ： 時間
Ｕ ： 熱伝達係数
Ａ ： 比表面積
Ｔ_{ｓｕｒｆａｃｅ} ： 試験用デバイスの表面温度
Ｔ_{ａｍｂｉｅｎｔ} ： 試験用デバイスの雰囲気温度
ｈｅａｔ ： 発熱速度In general, the following formula 1 holds for the result of the heating test.

However, in Expression 1, the values represented by the symbols are as follows.
ρ: Test device density Cp: Test device specific heat T: Test device temperature t: Time U: Heat transfer coefficient A: Specific surface area T _surface : Test device surface temperature T _ambient : Test device atmosphere Temperature heat: Heat generation rate

Here, in the temperature range in which no heat is generated during the heating test, the heat generation rate (heat) in Equation 1 is zero.
Therefore, the following formula 2 is established, and from this formula 2, the heat transfer coefficient (U) can be obtained. Here, in Expression 2, the value represented by each symbol is the same as that in Expression 1 above. In addition, it is preferable to previously obtain the density (ρ), specific heat (Cp), specific surface area (A), etc. of the test device used when obtaining the heat transfer coefficient from Equation 2.

In addition, although the average value may be used for the obtained heat transfer coefficient (U) regardless of the temperature, in order to increase the accuracy of the booth breakdown voltage A, it is preferable to express it as a function.
In addition, here, the heat transfer coefficient (U) is obtained by Equation 2 using a test device, but the method for obtaining the heat transfer coefficient (U) is not limited and can be obtained by any method. For example, in place of the test device, the other member using the same surface constituting member as the test device (for example, a case of a power storage and supply device to be evaluated packed with lead beads) is used. Depending on the method, the heat transfer coefficient (U) may be obtained using Equation 2. Also, for example, depending on the case, an appropriate document value can be used.

Next, using the obtained heat transfer coefficient (U), in the temperature region where heat generation due to thermal decomposition occurs, the surface temperature of the test device (measured by the oven heating test) by using Equation 1 above ( T _surface ) is converted into a heat generation rate (heat). Specifically, using the surface temperature (T _surface ) and ambient temperature (T _ambient ) of the test device obtained in the heating test, and the heat transfer coefficient (U) obtained as described above, the test device The relationship between heat generation rate and temperature is derived. The density (ρ), specific heat (Cp), specific surface area (A), and the like can be the same as those in Equation 2.

Next, the heat generation rate (heat) obtained by converting the surface temperature of the power storage and supply device as described above is normalized to the heat generation rate [W / m ³ ] per volume of the test device. Usually, the test device is formed as an electrode winding body or a laminated body, but it is preferable to measure this volume in advance. The normalization may be performed at another stage, for example, after the heat generation rate is integrated over time and converted into a heat generation amount. Furthermore, the “volume of the test device” is a volume of a portion where heat is generated in the test device, and does not include an exterior (for example, a can or a laminate) or an extra gap in the test device.

Next, the heat generation rate [W / m ³ ] obtained as described above is integrated with the time during which the heating test is performed, and the heat generation amount per unit volume of the test device is obtained.
Then, from the calorific value per unit volume, the total calorific value [J / m ³ ] used for calculating the converted dose is obtained. Here, the “volume of the power storage and supply device” is also the volume of the portion where heat is generated in the power storage and supply device, and the exterior (for example, cans and laminates) and excess gaps in the power storage and supply device are not Not included.

That is, the total calorific value [J] actually generated in the safety test is obtained by multiplying the calorific value per unit volume obtained in the heating test by the volume of the power storage and supply device that performs the safety test in the booth 1. Specifically, the calorific value per unit volume is 1.8 × 10 ⁹ [J / m ³ ], and the volume of the power storage and supply device is 7.2 × 10 ⁻⁵ [m ³ ]. The total calorific value of the amount of heat generated by the power storage and supply device subject to the safety test during the safety test is
(1.8 × 10 ⁹ [J / m ³ ]) × (7.2 × 10 ⁻⁵ [m ³ ]) = 1.3 × 10 ⁵ [J]
It becomes.

When a specific device such as a lithium ion battery is used as the power storage / supply device, the power capacity [J] of the power storage / supply device is usually 30% or more and 100% or less instead of performing the heating test. A value obtained by multiplying an appropriate coefficient value may be used as the total calorific value. For example, when a battery having a capacity of 10 Ah and an average voltage of 3.7 V is a subject of the safety test, the power capacity is 10 × 3.7 × 3600 = 1.3 × 10 ⁵ [J].
It becomes. Therefore, a value obtained by multiplying this by a coefficient value of 30% to 100% is regarded as the total heat generation amount of the battery, and the booth withstand voltage A is calculated even when performing the above calculations (2) to (6). be able to. The coefficient value multiplied by the power capacity may be obtained experimentally.
Moreover, as a total calorific value, an assumed value or a document value may be used. However, from the viewpoint of improving reliability, it is preferable to use experimental values.

(2) Identification of TNT dosage corresponding to the total calorific value generated during the safety test If the total calorific value generated during the safety test is determined, then the TNT dosage corresponding to the total calorific value is identified. Since the heat value during explosion of TNT is 2.6 × 10 ⁹ [J / ton], specifically, the total heat value may be divided by 2.6 × 10 ⁹ J / ton. In the case of the specific example of the heating test, the total amount of heat generated during the safety test is 1.3 × 10 ⁵ [J], so the corresponding TNT dosage is (1.3 × 10 ⁵ [J]) / ( 2.6 × 10 ⁹ [J / ton])
= 5 × 10 ⁻⁵ [ton]
= 0.05 [kg]
It is.

(3) Calculation of conversion dose Once the TNT dose corresponding to the total calorific value is known, the conversion dose to be applied to Hopkinson's third-root rule by multiplying the TNT dose by the above-mentioned TNT yield. Is calculated. In the case of the specific example of the heating test, the TNT dosage corresponding to the total calorific value is 0.05 [kg]. Therefore, when the TNT yield is 5%, the converted dosage is (0.05 [kg]. ]) × (0.05) = 2.5 × 10 ⁻³ [kg]
It becomes.

(4) Specifying the distance to the inner wall Separately, the distance from the power storage and supply device in the booth 1 to the target portion of the inner wall of the booth 1 is obtained. This distance is used for later calculation of the converted distance. In the specific example of the heating test, this distance is 0.35 m. Here, the target portion refers to a portion intended to have a pressure resistance higher than the booth breakdown voltage A.

(5) Calculation of conversion distance A conversion distance is calculated | required from the conversion dosage and the distance from the electric power storage supply device to the object site | part of the inner wall of the booth 1. FIG. Specifically, the conversion distance is calculated by dividing the distance from the power storage and supply device to the target part of the inner wall of the booth 1 by the cube root of the conversion dose. Moreover, since the site | part with the shortest distance from an electric power storage supply device receives the highest pressure in the inner wall of booth 1, a conversion distance is calculated | required using the shortest distance of an electric power storage supply device and an inner wall, and electric power storage is carried out by an inner wall. It is preferable to make the safety of the booth 1 as a whole with the pressure resistance required for the part where the distance from the supply device is the smallest, because the safety of the test can be further improved. In the specific example of the heating test, the conversion distance is
(0.35 [m]) / {(2.5 × 10 ⁻³ [kg]) ^(1/3) }
= 2.6 [m / kg ^(1/3) ]
It becomes.

(6) Identification of blast pressure Based on the converted distance obtained as described above, the blast pressure corresponding to the converted distance is specified. Specifically, the blast pressure on the vertical axis corresponding to the converted distance on the horizontal axis is specified using the correlation diagram shown in FIG. 2 showing the relationship between the converted distance and the blast pressure in Hopkinson's third-root rule. Therefore, in the specific example of the heating test, the value 2 [Kgf / cm ² ] on the vertical axis corresponding to the converted distance 2.6 [m / kg ^(1/3) ] on the horizontal axis is the relevant part of the booth 1. The blast pressure at

(7) Calculation of Booth Pressure A The booth pressure A at the target part of Booth 1 is calculated by multiplying the blast pressure by a safety factor. Therefore, when the safety factor is 1, the booth pressure resistance A of the target part in the specific example of the heating test is 2 [Kgf / cm ² ] × 1 (safety factor) = 2 [Kgf / cm ² ].
It becomes.

Therefore, when the safety test is performed in an inert atmosphere, the booth 1 has a pressure resistance higher than the above-described booth breakdown voltage A, preferably at least part of the wall, bottom, ceiling, etc. constituting the booth 1. It is desirable to be able to withstand the internal pressure up to the booth pressure resistance A.
In the present embodiment, it is assumed that the booth 1 includes a pressure sensor 11, and further, the booth 1 is configured to have a pressure resistance and an airtightness equal to or higher than the booth breakdown voltage A calculated as described above. In addition, since the booth 1 has a pressure resistance higher than the booth pressure A, the booth 1 can function as an exhaust gas holding unit in the test apparatus of the present embodiment.

Since the test apparatus of the present embodiment is configured as described above, a safety test can be performed in the same manner as in the first embodiment.
As described above, by using the test apparatus according to the present embodiment, it is possible to perform a safety test of an electric power storage and supply device while enabling treatment of exhaust gas. Further, when safety tests such as a nail penetration test, an overcharge test, and a heating test are performed on the power storage and supply device, a large amount of exhaust gas is rapidly generated. In the test apparatus of this embodiment, the exhaust gas delivery line 3 In order to adjust the flow rate of the exhaust gas sent out according to the processing capacity of the exhaust gas processing unit 2, temporarily hold the exhaust gas before flowing into the exhaust gas processing unit 2, and to the exhaust gas processing unit 2 according to the processing capacity Can be introduced. Therefore, there is no risk that exhaust gas exceeding the processing capacity will flow into the exhaust gas treatment unit 2 and the exhaust gas detoxification process cannot be performed, and a safety test can be performed safely.

Moreover, since the booth 1 is configured to have a pressure resistance higher than the booth pressure A, the test apparatus according to the present embodiment generates exhaust gas suddenly when the safety test is performed in an inert gas atmosphere. In addition, even if the exhaust gas is temporarily held in the booth 1, it is possible to more reliably prevent the booth 1 from being damaged, and the safety of the test can be further improved.
In addition, operations and effects similar to those of the first embodiment can be obtained.

[I-3. Third Embodiment]
The test apparatus as the third embodiment of the present invention is configured such that the indoor gas replacement line replaces the inside of the booth 1 with air, and the booth 1 has a pressure resistance higher than the booth pressure resistance B. Others are the same as in the first embodiment.

Therefore, also in the present embodiment, the power storage and supply device, the exhaust gas, and the safety test are the same as in the first embodiment.
As for the test apparatus, as shown in FIG. 1, the exhaust gas treatment unit 2, the exhaust gas delivery line 3, the decompression line 5, the coolant line 6 and the exhaust gas collection line 7 are the same as those in the first embodiment.

Further, the booth 1 is the same as the first embodiment except that the booth breakdown voltage is equal to or higher than the booth breakdown voltage B.
That is, in this embodiment as well, as in the first embodiment, the exhaust gas delivery line 3 sends exhaust gas according to the processing capacity of the exhaust gas treatment unit 2, so that the exhaust gas is temporarily sent to the booth 1. Thus, the exhaust gas does not flow into the exhaust gas processing unit 2 at an inflow rate exceeding the limit value of the exhaust gas processing rate of the exhaust gas processing unit 2. However, in the present embodiment, since the safety test is performed with the inside of the booth 1 as an air atmosphere, it is preferable that the booth 1 also has a pressure resistance corresponding to the safety test.

  When a safety test is performed in an air atmosphere and exhaust gas is generated in the safety test, the combustible component of the exhaust gas may be combusted in the air. However, the combustion flame temperature of the combustion usually does not exceed 2500 K which is an approximate value when a general organic combustible gas burns in air. Therefore, since the amount of exhaust gas generated compared to the volume of the booth 1 is very small, the amount of increase in the internal pressure of the booth 1 due to the generation of the exhaust gas itself is sufficiently small. That is, when the safety test is performed in an air atmosphere and the generated exhaust gas is burned, the exhaust gas is burned after the exhaust gas is generated rather than the influence of the amount of the exhaust gas generated from the power storage and supply device. The effect of thermal expansion due to the increase in internal temperature is greater. For this reason, when the safety test is performed in an air atmosphere and the booth 1 is provided with a pressure resistance that can withstand the explosion caused by the generation of the exhaust gas, the “temperature rise caused by the combustion of the combustible component of the exhaust gas” It is only necessary to have pressure resistance that can withstand “effects of

Therefore, when the safety test is performed with the air atmosphere in the booth 1 such as when the atmosphere in the booth 1 can be replaced with air in the indoor gas replacement line 4, the booth 1 has the following booth pressure resistance. It is preferable to have a pressure resistance of B or higher.
Booth pressure resistance B = initial pressure × (Tb / T0) × safety factor (where the initial pressure represents the internal pressure of booth 1 before exhaust gas generation during the safety test, and Tb represents the combustion flame temperature during the safety test, T0 represents the ambient temperature in the booth 1 before exhaust gas generation during the safety test, and the safety factor is the same value as described in the second embodiment, where Tb and T0 are absolute temperatures, respectively. Represents the value at.)

Here, the combustion flame temperature Tb is an atmospheric temperature during exhaust gas combustion, and the measurement method is arbitrary.
For example, the initial pressure is 0.1 MPa, the ambient temperature T0 in the booth 1 before exhaust gas generation during the safety test is 25 ° C. (298 K), and the safety test is performed. When the combustion flame temperature (2500 K) of Tb is Tb and the safety factor is 1, the booth withstand pressure B is: booth withstand pressure B = 0.1 MPa × 2500 (K) / 298 (K) × 1 = 0.8 MPa
It becomes.

Similarly to the second embodiment, the blast pressure is calculated using the Hopkinson's third-root rule, and the blast pressure is multiplied by the safety factor in the same manner as the second embodiment, and the booth 1 has a pressure higher than the blast pressure. You may make it provide pressure resistance.
In particular, when the power storage and supply device is a battery, use 10 times the mass of the electrolyte as the TNT dosage corresponding to the total calorific value in the method for calculating the blast pressure described in the second embodiment. Can do. In addition, as the mass of the electrolyte solution at this time, a value obtained by multiplying 1/3 of the volume of the battery by a density of 1000 kg / m ³ can be used.

Furthermore, when the heat of combustion of the electrolyte is known, the TNT dose may be determined using a TNT explosion heat value of 2.6 × 10 ⁹ J / ton. Specifically, the TNT dosage can be calculated by dividing the combustion heat of the electrolyte by the TNT explosion heat value.
Further, when the pressure resistance to be provided in the booth 1 when performing a safety test in an air atmosphere is obtained using Hopkinson's third root rule, the TNT yield is the same as in the second embodiment. Furthermore, an actual measurement value may be used as the TNT yield.

  However, in general, when the exhaust gas generated in the safety test is flammable in the air, a blast pressure larger than the blast pressure obtained using Hopkinson's third root rule is often generated in the safety test. . Therefore, when the booth 1 for performing a safety test in an air atmosphere is configured, if the exhaust gas generated in the safety test is not flammable in the air, it is obtained using Hopkinson's third-root rule. The booth pressure resistance A may be provided in the booth 1, but when the exhaust gas generated in the safety test is flammable in the air, or when the generated exhaust gas is unknown, this embodiment It is preferable to make the booth 1 have the booth breakdown voltage B described in the above.

Note that the pressure resistance required for the booth 1 depends on whether the safety test is performed in an inert atmosphere as in the first and second embodiments or in an air atmosphere as in the third embodiment. The difference is due to the following reasons. That is, under an inert atmosphere, oxygen used for decomposition and combustion reaction of combustible gas in the exhaust gas was originally present as oxygen in the power storage and supply device, or generated by decomposition of components. Only oxygen. On the other hand, when a safety test is performed in an air atmosphere, oxygen in the air is further added to the above oxygen. Therefore, when the safety test is performed in the air, the decomposition and combustion reaction proceeds more than when the safety test is performed under an inert atmosphere, and thus the required pressure resistance is different. .
In this embodiment, it is assumed that the booth 1 is configured to have a pressure resistance higher than the booth breakdown voltage B described above.

Further, in the test apparatus of the present embodiment, the indoor gas replacement line 4 performs replacement with air instead of the inert gas used in the first embodiment. Therefore, the indoor gas replacement line 4 functions as an air replacement section that can replace the interior of the booth 1 with air.
Thus, by replacing the interior of the booth 1 with air and performing the safety test in an air atmosphere, the power storage and supply device can be evaluated in a state close to the actual use state. It is also possible to analyze how the exhaust gas burns and explodes due to factors external to the power storage and supply device. Since oxygen is present in the booth 1, the pressure generated during the safety test under an air atmosphere is usually higher than the pressure generated during the safety test under an inert atmosphere. Therefore, there is no possibility that the exhaust gas cannot be retained or the booth 1 is damaged.

  Since the test apparatus of the present embodiment is configured as described above, except that the interior of the booth 1 is replaced with air using the indoor gas replacement line 4 when preparing for the safety test, the first embodiment is the same as the first embodiment. Similarly, a safety test can be performed.

  As described above, by using the test apparatus according to the present embodiment, it is possible to perform a safety test of an electric power storage and supply device while enabling treatment of exhaust gas. Further, when safety tests such as a nail penetration test, an overcharge test, and a heating test are performed on the power storage and supply device, a large amount of exhaust gas is rapidly generated. In the test apparatus of this embodiment, the exhaust gas delivery line 3 In order to adjust the flow rate of the exhaust gas sent out according to the processing capacity of the exhaust gas processing unit 2, temporarily hold the exhaust gas before flowing into the exhaust gas processing unit 2, and to the exhaust gas processing unit 2 according to the processing capacity Can be introduced. Therefore, there is no risk that exhaust gas exceeding the processing capacity will flow into the exhaust gas treatment unit 2 and the exhaust gas detoxification process cannot be performed, and a safety test can be performed safely.

Moreover, since the test apparatus of the present embodiment is configured so that the booth 1 has a pressure resistance equal to or higher than the booth breakdown voltage B, exhaust gas is rapidly generated when the safety test is performed in an air atmosphere, Further, even if the exhaust gas is temporarily held in the booth 1, the booth 1 is not damaged and the safety of the test can be further improved.
In addition, operations and effects similar to those of the first embodiment can be obtained.

[I-4. Others]
As mentioned above, although the embodiment of the test apparatus of the present invention has been shown and described, the test apparatus of the present invention is not limited to the above-described embodiment, and can be arbitrarily modified without departing from the gist of the present invention. Can be implemented.
For example, you may make it use each component demonstrated in said 1st, 2nd or 3rd embodiment arbitrarily combining, respectively.
Further, for example, the indoor gas replacement line 4 is provided with both a gas cylinder for supplying an inert gas and a gas cylinder for supplying air, and either the inert gas or the air is selectively replaced in the booth 1. You may comprise so that it can do. At this time, two or more indoor gas replacement lines 4 may be provided, and the inside of the booth 1 may be replaced with an inert gas or air in the single indoor gas replacement line 4 using a switching valve or the like. good. In this case, the booth 1 has a pressure resistance of a pressure resistance to be provided when performing a safety test in an inert atmosphere and a pressure resistance to be provided when performing a safety test in an air atmosphere. It is desirable to provide a higher pressure resistance.

Further, for example, when performing a safety test in an air atmosphere as in the third embodiment, the interior of the booth 1 is simply replaced with an air atmosphere through a door provided in the booth 1 without providing the dedicated indoor gas replacement line 4. You may make it do.
Furthermore, instead of providing the cooling line 6, a bus filled with a cooling medium may be installed in the booth 1 to cool the booth 1.

  Further, for example, when exhaust gas is collected by the exhaust gas collection line 7, a stirrer (fan or the like) for stirring the exhaust gas is installed in the booth 1 so that the exhaust gas can be made uniform. preferable. Thereby, it is possible to improve the reliability of exhaust gas analysis. In the above embodiment, the exhaust gas collection line 7 is extracted from the exhaust gas delivery line 3, but may be configured to include a dedicated pipe directly connected to the booth 1.

Further, for example, an analytical instrument (exhaust gas analysis unit) is provided in the test apparatus, and the analytical instrument and the sample container 72 are connected by a pipe so that the exhaust gas collected by the exhaust gas sampling line 7 can be analyzed by the test apparatus. May be. Thereby, analysis of exhaust gas can be performed more easily.
Further, for example, the exhaust gas after passing through the exhaust gas collection line 7 may be returned to the exhaust gas delivery line 3 again. Thereby, the quantity of the waste gas discharged | emitted out of a system without processing can be reduced more.

Moreover, you may make it install the test equipment other than what was illustrated by the said embodiment in the booth 1. FIG. For example, charging / discharging wiring for power storage and supply devices, wiring for current voltage measurement, testing machine control wiring, testing machine power supply wiring, power supply for lamps, power supply for stirrer, power supply for CCD camera, video and audio signal line, power Electrical measurement system test equipment such as pressure measurement sensor line in storage supply device, pressure measurement sensor line in booth; to measure booth atmosphere temperature, power storage supply device surface temperature, power storage supply device internal temperature, etc. Temperature measuring system test equipment.
Furthermore, a safety valve, a pressure relief valve, or the like may be provided in the booth 1 to further enhance safety.

  Further, when the indoor gas replacement line 4 is not provided, or when the atmosphere in the booth 1 is changed to an atmosphere of a gas other than an inert gas or air by the indoor gas replacement line 4, the above-mentioned booth pressure resistance is set in the booth 1. A or booth breakdown voltage B may be provided. Further, for example, when the exhaust gas generated by the safety test does not react with the gas present in the atmosphere in the booth 1, the booth 1 is set in the booth 1 when the atmosphere in the booth 1 is changed to the air atmosphere by the indoor gas replacement line 4. A withstand voltage A may be provided. For example, in order to give the test apparatus versatility, the booth 1 may be provided with the booth pressure resistance B regardless of the atmosphere existing in the atmosphere in the booth 1 during the safety test. As described above, whether the booth withstand voltage A or the booth withstand voltage B is provided in the booth 1 can be arbitrarily set as appropriate.

[II. Safety evaluation method]
If the test apparatus of the present invention described above is used, the safety test of the power supply device can be performed, and the safety evaluation of the power supply device can be performed based on the test result of the safety test. At this time, the type of safety test is not limited, but for example, selected from nail penetration test, overcharge test, heating test, external short circuit test, drop test, crush test, overdischarge test, thermal shock test, vibration test A test can be performed.

Although the content of the specific safety evaluation method is arbitrary, based on the above, for example, “International certification regarding safety of lithium ion battery (small battery)” UL1642, “Battery industry association guideline SBA G1101 lithium secondary battery” This can be done in accordance with certification regulations such as “Safety Evaluation Criteria Guidelines”.
At this time, since the test apparatus of the present invention has pressure resistance (sealing property), the gas generation amount and the gas composition can be analyzed more accurately by using this. Therefore, using this analysis result, it is possible to design and manufacture a safe power supply device with less gas generation or the like even in the event of breakdown or internal short circuit.

Measurement items in various evaluation tests can be measured by various sensors installed in the booth.
For example, the surface temperature of the power supply device and the gas temperature in the booth can be measured by a temperature sensor such as a thermocouple.
Further, for example, the amount of gas generated can be calculated by a gas equation of state. The above equation of state is obtained from the change in the booth internal pressure before and after the safety test obtained by the pressure sensor and the gas temperature in the booth obtained by the temperature sensor.
Further, for example, the component (composition) of the exhaust gas can be obtained by analyzing the gas collected from the exhaust gas collection line by a known analyzer or method such as gas chromatography or a mass spectrometer.
Further, for example, if a booth is equipped with a video camera and a lighting device necessary for photographing with the video camera, the visual behavior during the evaluation test can be captured.

[III. Non-aqueous electrolyte secondary battery]
The non-aqueous electrolyte secondary battery of the present invention has been developed using the test apparatus and the safety evaluation method, and includes a positive electrode and a negative electrode capable of occluding and releasing lithium ions, and a non-aqueous electrolyte. It is a non-aqueous electrolyte secondary battery.
The non-aqueous electrolyte secondary battery of the present invention satisfies the following condition (1) or condition (2), and preferably satisfies these conditions (1) and (2) at the same time. . Among them, it is more preferable that at least one of the conditions (3) and (4) is satisfied, and particularly preferable that the conditions (3) and (4) are satisfied at the same time.

[III-1. Conditions that non-aqueous electrolyte secondary battery must satisfy]
(1) Gas generation amount in overcharge test Condition (1) is a booth before and after the test when the non-aqueous electrolyte secondary battery of the present invention is subjected to an overcharge test under the following conditions using the above test apparatus. The change in internal pressure satisfies the following requirements at 25 ° C.
Requirements:
Change in booth pressure before and after the test [Pa] × booth internal volume [m ³ ] / (booth internal pressure [Pa] before test × battery volume [m ³ ]) ≦ C
In addition, in the said requirements, C is a coefficient which shows the gas generation amount at the time of a test, 100 times or less are preferable, 10 times or less are more preferable, and 1 time or less are especially preferable.

The conditions for the overcharge test are as follows.
(I) The initial temperature of the atmosphere in the booth is 20 ± 5 ° C.
(Ii) From a fully discharged state or from a charging depth of 0% (iii) Charging operation up to 250% of the charging capacity at a current 3 times the current recommended by the manufacturer of the non-aqueous electrolyte secondary battery Do
(V) Measure the increase in booth internal pressure due to gas generation during the test process.

In the overcharge test condition, the initial temperature of the atmosphere in the booth in the condition (i) may be measured at any position in the booth. However, the temperature is usually measured at a distance of 20 mm or more from the nonaqueous electrolyte secondary battery present in the booth.
Further, in condition (ii), whether or not the non-aqueous electrolyte secondary battery is completely discharged can be confirmed by checking that the battery voltage is lower than the lower limit voltage in the normal voltage range. On the other hand, the charge depth of 0% can be confirmed by the fact that the discharge capacity flowing when the battery voltage is maintained at the lower limit voltage in the normal voltage range for 30 minutes is 2% or less of the battery capacity. The normal voltage range here refers to the voltage range between the upper limit voltage during charging and the lower limit voltage during discharging, and this is generally the charge / discharge cycle life and storage life, the extent of gas generation, and whether there is an internal short circuit. In consideration of battery characteristics such as discharge capacity, it is determined to suit the intended use and recommended by the manufacturer. This range varies depending on the specification material, internal structure, and usage environment of the non-aqueous electrolyte secondary battery. For example, in the case of a lithium ion secondary battery, the normal voltage range is generally 2.5 V to 4.2 V. is there.
Furthermore, the current recommended by the manufacturer refers to a current having a current value recommended by the manufacturer. Therefore, the condition (iii) represents that charging is performed with a current having a current value that is three times the recommended current value.
In addition, under conditions (iv) and (v), charging is ideally performed up to 250% of the charging capacity, but gas is generated before the charging amount reaches 250% of the charging capacity, and the charging capacity is 250%. If it does not reach the maximum value, the battery is charged up to the maximum chargeable amount, and the increase in the booth internal pressure at the time of charging up to the maximum amount is measured.
The atmosphere in the booth is arbitrary, and may be an inert gas, air, or other gas depending on circumstances.

  The overcharge test is a test for analyzing the behavior of the non-aqueous electrolyte secondary battery when the non-aqueous electrolyte secondary battery is excessively charged. As a result of this overcharge test, satisfying the above requirements means that if the non-aqueous electrolyte secondary battery is opened, ruptured, or exploded during overcharge, the non-aqueous electrolyte secondary battery This indicates that the degree of gas generation and the magnitude of impact caused by gas generation are so small that they do not cause any practical problems.

  The level of gas generated during overcharge and the level of impact generated by gas generation are complicatedly related to the type, amount, and arrangement of battery elements of the non-aqueous electrolyte secondary battery. Therefore, when trying to develop a non-aqueous electrolyte secondary battery with a low level of gas generation and a low level of impact caused by gas generation, the non-aqueous electrolyte secondary battery is actually overcharged. To generate gas and repeat the analysis many times. Therefore, it can be expected that the development progresses better as the superior test apparatus for performing the test is used, and the performance and function of the test apparatus are developed using the test apparatus. It is considered to be reflected in the secondary battery.

  Note that manufacturers of non-aqueous electrolyte secondary batteries usually recommend an amount of current that can be suitably used from the viewpoints of safety and efficiency. Here, the above overcharge test is repeated when determining the recommended amount of current. Therefore, the performance and function of the test device will correlate with the current value recommended by the manufacturer of the non-aqueous electrolyte secondary battery for the non-aqueous electrolyte secondary battery developed using the test device. Inferred.

(2) Gas generation amount in the nail penetration test Condition (2) is the booth before and after the test when the non-aqueous electrolyte secondary battery of the present invention was subjected to the nail penetration test under the following conditions using the above test apparatus. The change in internal pressure satisfies the following requirements at 25 ° C.
Requirements:
Change in booth pressure before and after the test [Pa] × booth internal volume [m ³ ] / (booth internal pressure [Pa] before test × battery volume [m ³ ]) ≦ C
In the above requirements, C is a coefficient indicating the amount of gas generated during the test, preferably 100 times or less, more preferably 10 times or less, and particularly preferably 1 time or less.

The conditions for the nail penetration test are as follows.
(I) The initial temperature of the atmosphere in the booth is 20 ± 5 ° C.
(Ii) A nail having a diameter of 2.5 mm to 5 mm is penetrated in the center of the non-aqueous electrolyte secondary battery in a direction perpendicular to the electrode surface, and left for 6 hours or more.
(Iii) Measure the increase in booth internal pressure due to gas generation during the test process.

In the nail penetration test condition, the initial temperature of the atmosphere in the booth in the condition (i) may be measured at any position in the booth. However, the temperature is usually measured at a distance of 20 mm or more from the nonaqueous electrolyte secondary battery present in the booth.
In the condition (ii), the central portion of the non-aqueous electrolyte secondary battery refers to the range of 10 mm around the center point of the electrode surface (positive electrode or negative electrode surface). Further, the standing time is not limited as long as it is 6 hours or longer, but is usually 24 hours or shorter.
The atmosphere in the booth is arbitrary, and may be an inert gas, air, or other gas depending on circumstances.

  The above nail penetration test is performed when the non-aqueous electrolyte secondary battery is damaged or when a short circuit occurs due to impact or vibration applied from the outside of the non-aqueous electrolyte secondary battery. This is a test for analyzing the behavior of As a result of this nail penetration test, satisfying the above requirements means that when the non-aqueous electrolyte secondary battery opens, ruptures, or explodes when a short circuit occurs, the non-aqueous electrolyte secondary battery This means that the degree of gas generation and the strength of impact caused by gas generation are small enough not to cause a problem in practice.

  The degree of gas generation generated at the occurrence of a short circuit and the level of impact generated by gas generation are also complicatedly related to the type, amount, and arrangement of battery elements of the non-aqueous electrolyte secondary battery. Therefore, as in the case of the overcharge test, when trying to develop a non-aqueous electrolyte secondary battery, it is necessary to repeatedly perform analysis by actually causing a short circuit in the non-aqueous electrolyte secondary battery. Will repeat. Therefore, it is considered that the performance and function of the test apparatus are also reflected in the non-aqueous electrolyte secondary battery developed using the test apparatus.

(3) Battery surface temperature in the heating test Condition (3) is the non-aqueous electrolyte secondary battery of the present invention when the heating test is performed under the following conditions using the above test apparatus. The surface temperature of the aqueous electrolyte secondary battery is not more than 50K higher than the ambient temperature in which the non-aqueous electrolyte secondary battery exists. Further, the surface temperature of the nonaqueous electrolyte secondary battery preferably does not exceed 20K, more preferably does not exceed 10K, and particularly preferably does not exceed 5K. That is, the difference between the surface temperature and the ambient temperature of the non-aqueous electrolyte secondary battery is usually less than 50K, preferably less than 20K, more preferably less than 10K, and particularly preferably less than 5K.

The conditions for the heating test are as follows.
(I) From the initial temperature of the booth atmosphere 20 ± 5 ° C,
(Ii) The temperature of the atmosphere in the booth reaches 150 ± 2 ° C. at a temperature increase rate of 1 K / min to 5 K / min, and the temperature of the atmosphere in the booth is maintained at 150 ± 2 ° C. for 10 minutes.
(Iii) The surface temperature of the non-aqueous electrolyte secondary battery in the test process is measured throughout the test.

In the heating test conditions, the initial temperature of the atmosphere in the booth in condition (i) may be measured at any position in the booth. However, the temperature is usually measured at a distance of 20 mm or more from the nonaqueous electrolyte secondary battery present in the booth.
Furthermore, in the condition (iii), the surface temperature of the non-aqueous electrolyte secondary battery can be measured with a thermocouple, a platinum resistance temperature detector, a thermistor, a radiation thermometer, or the like.
In the heating test, the pressure in the booth at the initial stage of the test is usually preferably atmospheric pressure (0.1 MPa).
The atmosphere in the booth is arbitrary, and may be an inert gas, air, or other gas depending on circumstances.

  The heating test is a test for analyzing the degree of abnormal reaction at a high temperature. As a result of this heating test, satisfying the above requirements indicates that the degree of abnormal reaction at a high temperature is low, and as a result, the degree of abnormal temperature rise of the battery and the generation of gas from the battery are low. .

  The degree of abnormal reaction during heating is also complicatedly related to the type, amount, arrangement, etc. of the battery elements of the non-aqueous electrolyte secondary battery. Therefore, as in the case of the overcharge test and the nail penetration test, when trying to develop a non-aqueous electrolyte secondary battery, a heating test is actually performed on the non-aqueous electrolyte secondary battery for analysis. It will be repeated many times. At this time, a large amount of gas may be generated from the non-aqueous electrolyte secondary battery during the test process, so the test booth must be able to withstand the increase in the booth internal pressure due to gas generation and be equipped with a function for processing the generated gas. Is desirable. Therefore, it is considered that the performance and function of the test apparatus are also reflected in the non-aqueous electrolyte secondary battery developed using the test apparatus.

(4) Preferred Properties Furthermore, the non-aqueous electrolyte secondary battery of the present invention particularly preferably satisfies at least one property selected from the group consisting of the following (a), (b) and (c).
(A) The non-aqueous electrolyte secondary battery includes an exterior, and the total electrode area of the positive electrode with respect to the surface area of the exterior is 20 times or more in area ratio.
(B) The non-aqueous electrolyte secondary battery has a DC resistance component of 10 milliohms (mΩ) or less.
(C) The non-aqueous electrolyte secondary battery has an exterior, and the electric capacity of a battery element housed in one of the exteriors is 3 ampere hours (Ah) or more.
In addition, in said property (a), the exterior and surface area (outer surface area) of a nonaqueous electrolyte secondary battery are mentioned later.

The non-aqueous electrolyte secondary battery satisfying the above-mentioned property (a) is preferable because it has an advantage that a battery smaller than the discharge capacity can be obtained because the discharge capacity density is large.
Moreover, the non-aqueous electrolyte secondary battery satisfying the property (b) is preferable because it has an advantage that a large current discharge can be performed because the battery internal resistance during charging and discharging is small.
Furthermore, the non-aqueous electrolyte secondary battery satisfying the property (c) is preferable because it has an advantage that the discharge capacity is large and power can be supplied for a long time.
Further, those satisfying two of these properties simultaneously in an arbitrary combination are more preferable, and those satisfying three simultaneously are particularly preferable.

[III-2. Configuration of non-aqueous electrolyte secondary battery]
Hereinafter, the non-aqueous electrolyte secondary battery of the present invention having the above characteristics will be described in more detail. However, the non-aqueous electrolyte secondary battery of the present invention is not limited to the battery having the configuration described below, and includes a wide range of batteries that satisfy the conditions (1) to (4) as described above. That is, the non-aqueous electrolyte secondary battery that satisfies the conditions (1) to (4) as described above is considered to have been developed through safety evaluation using the test apparatus of the present invention, and will be described below. The configuration is a preferred example of the configuration of the non-aqueous electrolyte secondary battery of the present invention.

[III-2-1. Battery shape]
The battery shape of the non-aqueous electrolyte secondary battery of the present invention is not particularly limited, and examples thereof include a bottomed cylindrical shape, a bottomed square shape, a thin shape, a sheet shape, and a paper shape. In addition, in order to increase volumetric efficiency and improve storage when incorporated in a system or device, it is of a different shape such as a horseshoe shape or a comb shape considering the fit in the peripheral system arranged around the battery. Also good. Furthermore, from the viewpoint of efficiently releasing the heat inside the battery to the outside, a rectangular shape having at least one surface that is relatively flat and has a large area is preferable.

  In a battery having a bottomed cylindrical shape, since the outer surface area with respect to the power generating element to be filled becomes small, it is preferable to design so that Joule heat generated by the internal resistance at the time of charging and discharging efficiently escapes to the outside. Moreover, it is preferable to design so that the filling ratio of the substance having high thermal conductivity is increased and the temperature distribution inside is reduced.

In the bottomed square shape, the ratio between the area S of the largest surface (the product of the width and height of the outer dimensions excluding the terminal portion, unit m ² ) and the thickness T (unit m) of the battery outer shape The 2S / T value is preferably 100 or more, and more preferably 200 or more. By increasing the maximum surface, it is possible to improve characteristics such as cycleability and high-temperature storage even for high-power and large-capacity batteries, and increase the heat dissipation efficiency during abnormal heat generation. It is possible to suppress a dangerous state of “rupture”.

[III-2-2. Battery configuration]
The non-aqueous electrolyte secondary battery of the present invention includes at least a positive electrode and a negative electrode capable of occluding and releasing lithium ions, a non-aqueous electrolyte, a separator disposed between the positive electrode and the negative electrode, a current collecting terminal, and an outer case. Composed. If necessary, a protective element may be mounted inside the battery and / or outside the battery.

[III-2-2-1. Positive electrode]
The positive electrode used for the non-aqueous electrolyte secondary battery of the present invention will be described below.
[III-2-2-1-1. Cathode active material]
The positive electrode active material used for the positive electrode is described below.

[composition]
The positive electrode active material is not particularly limited as long as it can electrochemically occlude and release lithium ions. A substance containing lithium and at least one transition metal is preferable, and examples thereof include a lithium transition metal composite oxide and a lithium-containing transition metal phosphate compound.

V, Ti, Cr, Mn, Fe, Co, Ni, Cu, etc. are preferable as the transition metal of the lithium transition metal composite oxide. Specific examples include lithium-cobalt composite oxides such as LiCoO ₂ and LiNiO ₂ . Lithium / nickel composite oxide, lithium / manganese composite oxide such as LiMnO ₂ , LiMn ₂ O ₄ , Li ₂ MnO _3, etc., and some of the transition metal atoms that are the main components of these lithium transition metal composite oxides are Al, Ti , V, Cr, Mn, Fe, Co, Li, Ni, Cu, Zn, Mg, Ga, Zr, and those substituted with other metals such as Si. As specific examples of the substituted ones, for example, LiNi _0.5 Mn _0.5 O ₂ , LiNi _0.85 Co _0.10 Al _0.05 O ₂ , LiNi _0.33 Co _0.33 Mn _0.33 O ₂ , LiMn _1.8 Al _0.2 O ₄ , LiMn _1.5 Ni _0.5 O _{4 and the} like.

As the transition metal of the lithium-containing transition metal phosphate compound, V, Ti, Cr, Mn, Fe, Co, Ni, Cu and the like are preferable, and specific examples include, for example, LiFePO ₄ , Li ₃ Fe ₂ (PO ₄ ). ₃ , iron phosphates such as LiFeP ₂ O ₇ , cobalt phosphates such as LiCoPO ₄ , and some of the transition metal atoms that are the main components of these lithium transition metal phosphate compounds are Al, Ti, V, Cr, Mn , Fe, Co, Li, Ni, Cu, Zn, Mg, Ga, Zr, Nb, Si and the like substituted with other metals.

[Surface coating]
In addition, a material in which a substance having a composition different from that of the substance constituting the main cathode active material is attached to the surface of the cathode active material can be used. Surface adhering substances include aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, magnesium oxide, calcium oxide, boron oxide, antimony oxide, bismuth oxide, lithium sulfate, sodium sulfate, potassium sulfate, magnesium sulfate, calcium sulfate And sulfates such as aluminum sulfate and carbonates such as lithium carbonate, calcium carbonate and magnesium carbonate.

  These surface adhering materials are, for example, dissolved or suspended in a solvent and impregnated and added to the positive electrode active material, and dried. It can be made to adhere to the positive electrode active material surface by the method of making it react by the method etc., the method of adding to a positive electrode active material precursor, and baking simultaneously.

  The amount of the surface adhering substance is by mass with respect to the positive electrode active material, preferably 0.1 ppm or more, more preferably 1 ppm or more, still more preferably 10 ppm or more, and the upper limit is preferably 20% or less, more preferably 10%. % Or less, more preferably 5% or less. The surface adhering substance can suppress the oxidation reaction of the non-aqueous electrolyte solution on the surface of the positive electrode active material, and can improve the battery life. However, when the amount of the adhering quantity is too small, the effect is not sufficiently exhibited. If the amount is too large, the resistance may increase in order to inhibit the entry and exit of lithium ions.

[shape]
As the shape of the positive electrode active material particles, a lump shape, a polyhedron shape, a sphere shape, an oval sphere shape, a plate shape, a needle shape, a column shape, etc., which are conventionally used, are used. Thus, it is preferable that the secondary particles have a spherical or elliptical shape. In general, an electrochemical element expands and contracts as the active material in the electrode expands and contracts as it is charged and discharged. Therefore, the active material is easily damaged due to the stress or the conductive path is broken. Therefore, it is preferable that the primary particles are aggregated to form secondary particles, rather than a single particle active material having only primary particles, in order to relieve expansion and contraction stress and prevent deterioration. In addition, spherical or oval spherical particles are less oriented during molding of the electrode than plate-like equiaxed particles, so that the electrode is less expanded and contracted during charge and discharge, and the electrode is produced. The mixing with the conductive agent is also preferable because it can be easily mixed uniformly.

[Tap density]
The tap density of the positive electrode active material is usually 1.3 g / cm ³ or more, preferably 1.5 g / cm ³ or more, more preferably 1.6 g / cm ³ or more, and most preferably 1.7 g / cm ³ or more. . If the tap density of the positive electrode active material is lower than the lower limit, the amount of the required dispersion medium increases when the positive electrode active material layer is formed, and the necessary amount of conductive material and binder (binder) increases, leading to the positive electrode active material layer. In some cases, the positive electrode active material filling rate is restricted, and the battery capacity is restricted. By using a metal composite oxide powder having a high tap density, a high-density positive electrode active material layer can be formed. In general, the tap density is preferably as large as possible, but there is no particular upper limit. However, if the tap density is too large, diffusion of lithium ions using the non-aqueous electrolyte solution as a medium in the positive electrode active material layer becomes rate-determining, and load characteristics may be likely to deteriorate. Usually, it is 2.5 g / cm ³ or less, preferably 2.4 g / cm ³ or less.

In the present invention, the tap density is measured by passing a sieve having a mesh size of 300 μm, dropping the sample onto a 20 cm ³ tapping cell to fill the cell volume, and then measuring a powder density meter (for example, a tap denser manufactured by Seishin Enterprise Co., Ltd.). , Tapping with a stroke length of 10 mm is performed 1000 times, and the density obtained from the volume and the weight of the sample is defined as the tap density.

[Median diameter d ₅₀ ]
The median diameter d _{50 of the} particles (secondary particle diameter when primary particles are aggregated to form secondary particles) is usually 0.1 μm or more, preferably 0.5 μm or more, more preferably 1 μm or more, most The upper limit is usually 20 μm or less, preferably 18 μm or less, more preferably 16 μm or less, and most preferably 15 μm or less. If the lower limit is not reached, a high bulk density product may not be obtained. If the upper limit is exceeded, it takes time for the diffusion of lithium in the particles. When a conductive agent, a binder, or the like is slurried with a solvent and applied as a thin film, a phenomenon such as streaking may occur. Here, by mixing two or more kinds of positive electrode active materials having different median diameters d ₅₀ , the filling property at the time of producing the positive electrode can be further improved.

The median diameter d ₅₀ in the present invention is measured by a known laser diffraction / scattering type particle size distribution measuring apparatus. When LA-920 manufactured by HORIBA is used as a particle size distribution meter, a 0.1% by mass sodium hexametaphosphate aqueous solution is used as a dispersion medium for measurement, and a measurement refractive index of 1.24 is set after ultrasonic dispersion for 5 minutes. Measured.

[Average primary particle size]
When primary particles are aggregated to form secondary particles, the average primary particle diameter of the positive electrode active material is usually 0.01 μm or more, preferably 0.05 μm or more, more preferably 0.08 μm or more, Most preferably, it is 0.1 μm or more, and the upper limit is usually 3 μm or less, preferably 2 μm or less, more preferably 1 μm or less, and most preferably 0.6 μm or less. If the above upper limit is exceeded, it is difficult to form spherical secondary particles, which adversely affects the powder filling property, or the specific surface area is greatly reduced, so that there is a high possibility that battery performance such as output characteristics will deteriorate. is there. On the other hand, when the value falls below the lower limit, a phenomenon such as inferior charge / discharge reversibility may occur due to an undeveloped crystal.

  The primary particle diameter is measured by observation using a scanning electron microscope (SEM). Specifically, in a photograph at a magnification of 10000 times, the longest value of the intercept by the left and right boundary lines of the primary particles with respect to the horizontal straight line is obtained for any 50 primary particles and obtained by taking the average value. It is done.

[BET specific surface area]
The BET specific surface area of the positive electrode active material is 0.2 m ² / g or more, preferably 0.3 m ² / g or more, more preferably 0.4 m ² / g or more, 4.0 m ² / g or less, preferably 2 .5m ² / g or less, still more preferably not more than 1.5 m ² / g. When the BET specific surface area is smaller than this range, the battery performance tends to be lowered, and when the BET specific surface area is larger, the tap density is hardly increased, and the applicability at the time of forming the positive electrode active material is likely to be lowered.

  The BET specific surface area is determined by using a surface area meter (for example, a fully automated surface area measuring device manufactured by Okura Riken), preliminarily drying the sample for 30 minutes at 150 ° C. under nitrogen flow, and then measuring the relative pressure of nitrogen relative to atmospheric pressure. It is defined by a value measured by a nitrogen adsorption BET one-point method using a gas flow method using a nitrogen-helium mixed gas that is accurately adjusted to have a value of 0.3.

[Production method]
As a manufacturing method of the positive electrode active material, a general method is used as a manufacturing method of the inorganic compound. In particular, various methods are conceivable for producing a spherical or elliptical active material. For example, transition metal raw materials such as transition metal nitrates and sulfates and, if necessary, raw materials of other elements such as water can be used. Dissolve or pulverize and disperse in a solvent, adjust the pH while stirring to produce and recover a spherical precursor, and dry it as necessary. Then, LiOH, Li ₂ CO ₃ , LiNO _{3 and} other Li A method of obtaining an active material by adding a source and baking at a high temperature, transition metal raw materials such as transition metal nitrates, sulfates, hydroxides and oxides, and if necessary, raw materials of other elements in a solvent such as water Dissolve or pulverize and disperse in the powder and dry mold it with a spray drier to make a spherical or oval spherical precursor. To this, add a Li source such as LiOH, Li ₂ CO ₃ , or LiNO ₃ and calcinate at a high temperature. How to get active material Transition metal source materials such as transition metal nitrates, sulfates, hydroxides and oxides, Li sources such as LiOH, Li ₂ CO ₃ and LiNO ₃ , and source materials of other elements as necessary, such as water Examples thereof include a method of dissolving or pulverizing and dispersing in a solvent and drying and molding it with a spray dryer or the like to obtain a spherical or elliptical precursor, which is fired at a high temperature to obtain an active material.

[III-2-2-1-2. Configuration of positive electrode]
Below, the structure of the positive electrode used for this invention is described.
[Electrode structure and fabrication method]
The positive electrode is produced by forming a positive electrode active material layer containing positive electrode active material particles and a binder on a current collector. Manufacture of the positive electrode using a positive electrode active material can be performed by a conventional method. That is, a positive electrode active material and a binder, and if necessary, a conductive material and a thickener mixed in a dry form are pressure-bonded to a positive electrode current collector, or these materials are liquid media A positive electrode can be obtained by forming a positive electrode active material layer on the current collector by applying it to a positive electrode current collector and drying it as a slurry by dissolving or dispersing in a slurry.

  The content of the positive electrode active material in the positive electrode active material layer is usually 10% by mass or more, preferably 30% by mass or more, and particularly preferably 50% by mass or more. Moreover, it is 99.9 mass% or less normally, Preferably it is 99 mass% or less. When the content of the positive electrode active material in the positive electrode active material layer is low, the electric capacity may be insufficient. Conversely, if the content is too high, the strength of the positive electrode may be insufficient. In addition, the positive electrode active material powder of this invention may be used individually by 1 type, and may use together 2 or more types of a different composition or different powder physical properties by arbitrary combinations and ratios.

[Conductive material]
A known conductive material can be arbitrarily used as the conductive material. Specific examples include metal materials such as copper and nickel; graphite such as natural graphite and artificial graphite (graphite); carbon black such as acetylene black; and carbonaceous materials such as amorphous carbon such as needle coke. In addition, these may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  In the positive electrode active material layer, the conductive material is usually 0.01% by mass or more, preferably 0.1% by mass or more, more preferably 1% by mass or more, and the upper limit is usually 50% by mass or less, preferably 30% by mass. % Or less, more preferably 15% by mass or less. If the content is lower than this range, the conductivity may be insufficient. Conversely, if the content is higher than this range, the battery capacity may decrease.

[Binder]
The binder used in the production of the positive electrode active material layer is not particularly limited, and in the case of a coating method, any material that can be dissolved or dispersed in the liquid medium used in electrode production may be used. Resin polymers such as polyethylene, polypropylene, polyethylene terephthalate, polymethyl methacrylate, aromatic polyamide, cellulose, nitrocellulose; SBR (styrene butadiene rubber), NBR (acrylonitrile butadiene rubber), fluorine rubber, isoprene rubber, butadiene Rubber, ethylene-propylene rubber and other rubbery polymers; styrene / butadiene / styrene block copolymers or hydrogenated products thereof, EPDM (ethylene / propylene / diene terpolymer), styrene / ethylene / butadiene / ethylene copolymer Polymer, styrene / isoprene Thermoplastic elastomeric polymers such as styrene block copolymers or hydrogenated products thereof; syndiotactic-1,2-polybutadiene, polyvinyl acetate, ethylene / vinyl acetate copolymers, propylene / α-olefin copolymers, etc. Soft polymer such as polyvinylidene fluoride (PVdF), polytetrafluoroethylene, fluorinated polyvinylidene fluoride, polytetrafluoroethylene / ethylene copolymer, etc .; alkali metal ions (especially lithium ions) Examples thereof include a polymer composition having ion conductivity. In addition, these substances may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

  The ratio of the binder in the positive electrode active material layer is usually 0.1% by mass or more, preferably 1% by mass or more, more preferably 3% by mass or more, and the upper limit is usually 80% by mass or less, preferably 60%. It is not more than mass%, more preferably not more than 40 mass%, most preferably not more than 10 mass%. When the ratio of the binder is too low, the positive electrode active material cannot be sufficiently retained and the positive electrode has insufficient mechanical strength, which may deteriorate battery performance such as cycle characteristics. On the other hand, if it is too high, battery capacity and conductivity may be reduced.

[Liquid medium]
The liquid medium for forming the slurry may be any type of solvent that can dissolve or disperse the positive electrode active material, the conductive agent, the binder, and the thickener used as necessary. There is no particular limitation, and either an aqueous solvent or an organic solvent may be used.

  Examples of the aqueous medium include water, a mixed medium of alcohol and water, and the like. Examples of the organic medium include aliphatic hydrocarbons such as hexane; aromatic hydrocarbons such as benzene, toluene, xylene, and methylnaphthalene; heterocyclic compounds such as quinoline and pyridine; ketones such as acetone, methyl ethyl ketone, and cyclohexanone. Esters such as methyl acetate and methyl acrylate; amines such as diethylenetriamine and NN-dimethylaminopropylamine; ethers such as diethyl ether and tetrahydrofuran (THF); N-methylpyrrolidone (NMP) and dimethylformamide And amides such as dimethylacetamide; aprotic polar solvents such as hexamethylphosphalamide and dimethyl sulfoxide. In addition, a liquid medium may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

[Thickener]
In particular, when an aqueous medium is used, it is preferable to make a slurry using a thickener and a latex such as styrene-butadiene rubber (SBR). A thickener is usually used to adjust the viscosity of the slurry. The thickener is not particularly limited, and specific examples include carboxymethyl cellulose, methyl cellulose, hydroxymethyl cellulose, ethyl cellulose, polyvinyl alcohol, oxidized starch, phosphorylated starch, casein, and salts thereof. These may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and a ratio.

  Furthermore, when using a thickener, the ratio of the thickener to the active material is 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 0.6% by mass or more. Is usually 5% by mass or less, preferably 3% by mass or less, more preferably 2% by mass or less. Below this range, applicability may be significantly reduced. If it exceeds, the ratio of the active material in the positive electrode active material layer may decrease, the battery capacity may decrease, and the resistance between the positive electrode active materials may increase.

[Consolidation]
The positive electrode active material layer obtained by coating and drying is preferably consolidated by a hand press, a roller press or the like in order to increase the packing density of the positive electrode active material. The density of the positive electrode active material layer is preferably 1 g / cm ³ or more as a lower limit, more preferably 1.5 g / cm ³ , still more preferably 2 g / cm ³ or more, and the upper limit is preferably 4 g / cm ³ or less. The range is preferably 3.5 g / cm ³ or less, more preferably 3 g / cm ³ or less. If this range is exceeded, the permeability of the non-aqueous electrolyte solution to the vicinity of the current collector / active material interface may decrease, and the charge / discharge characteristics at a high current density may decrease. On the other hand, if it is lower, the conductivity between the active materials may be reduced, and the battery resistance may be increased.

[Current collector]
There is no restriction | limiting in particular as a material of a positive electrode electrical power collector, A well-known thing can be used arbitrarily. Specific examples include metal materials such as aluminum, stainless steel, nickel plating, titanium, and tantalum; and carbonaceous materials such as carbon cloth and carbon paper. Of these, metal materials, particularly aluminum, are preferred.

  Examples of the shape of the current collector include metal foil, metal cylinder, metal coil, metal plate, metal thin film, expanded metal, punch metal, foam metal, etc. A carbon thin film, a carbon cylinder, etc. are mentioned. Of these, metal thin films are preferred. In addition, you may form a thin film suitably in mesh shape. The thickness of the thin film is arbitrary, but is usually 1 μm or more, preferably 3 μm or more, more preferably 5 μm or more, and usually 1 mm or less, preferably 100 μm or less, more preferably 50 μm or less. If the thin film is thinner than this range, the strength required for the current collector may be insufficient. Conversely, if the thin film is thicker than this range, the handleability may be impaired.

  The ratio of the thickness of the current collector to the positive electrode active material layer is not particularly limited, but the (active material layer thickness on one side immediately before the nonaqueous electrolyte solution injection) / (current collector thickness) is 150 or less. Preferably, it is 20 or less, more preferably 10 or less, and the lower limit is preferably 0.1 or more, particularly preferably 0.4 or more, more preferably 1 or more. Above this range, the current collector may generate heat due to Joule heat during high current density charge / discharge. Below this range, the volume ratio of the current collector to the positive electrode active material increases and the battery capacity may decrease.

[Electrode area]
From the viewpoint of increasing the stability at high output and high temperature, the area of the positive electrode active material layer is preferably larger than the outer surface area of the battery outer case. Specifically, the total electrode area of the positive electrode with respect to the surface area of the exterior of the secondary battery is preferably 20 times or more, and more preferably 40 times or more. The outer surface area of the outer case is the total area obtained by calculation from the vertical, horizontal, and thickness dimensions of the case part filled with the power generation element excluding the protruding part of the terminal in the case of a bottomed square shape. . In the case of a bottomed cylindrical shape, the geometric surface area approximates the case portion filled with the power generation element excluding the protruding portion of the terminal as a cylinder. The total electrode area of the positive electrode is the geometric surface area of the positive electrode mixture layer facing the mixture layer containing the negative electrode active material, and in the structure in which the positive electrode mixture layer is formed on both sides via the current collector foil. , The sum of the areas where each surface is calculated separately.

[Discharge capacity]
When using the non-aqueous electrolyte for a secondary battery of the present invention, as described above, the electric capacity of the battery element housed in one battery exterior of the secondary battery (the battery is discharged from a fully charged state to a discharged state). When the electric capacity is 3 Ah or more, the effect of improving the low-temperature discharge characteristics is increased, which is preferable. Therefore, the positive electrode plate is designed so that the discharge capacity is fully charged and is usually 3 Ah or more, preferably 4 Ah or more, and usually 20 Ah or less, preferably 10 Ah or less. If it is less than 3 Ah, the voltage drop due to the electrode reaction resistance becomes large when taking out a large current, and the power efficiency may deteriorate. If it is larger than 20 Ah, the electrode reaction resistance is reduced and the power efficiency is improved, but the temperature distribution due to the internal heat generation of the battery during pulse charge / discharge is large, the durability of repeated charge / discharge is inferior, and overcharge, internal short circuit, etc. The heat radiation efficiency also deteriorates due to sudden heat generation at the time of abnormality, and the probability that the internal pressure rises and the gas release valve operates (valve operation) and the battery contents erupt violently (explosion) increases. There is a case.

[Thickness of positive electrode plate]
The thickness of the positive electrode plate is not particularly limited. From the viewpoint of high capacity, high output, and high rate characteristics, the thickness of the composite material layer minus the metal foil thickness of the core material is The lower limit for one surface is preferably 10 μm or more, more preferably 20 μm or more, and the upper limit is preferably 200 μm or less, more preferably 100 μm or less.

[III-2-2-2. Negative electrode]
The negative electrode used for the non-aqueous electrolyte secondary battery of the present invention will be described below.
[III-2-2-2-1. Negative electrode active material]
The negative electrode active material used for the negative electrode is described below.

  The negative electrode active material is not particularly limited as long as it can electrochemically occlude and release lithium ions. Carbonaceous materials, metal oxides such as tin oxide and silicon oxide, metal composite oxides, lithium simple substance And lithium alloys such as lithium aluminum alloy and metals that can form alloys with lithium such as Sn and Si. These may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and a ratio. Of these, carbonaceous materials or lithium composite oxides are preferably used from the viewpoint of safety.

  The metal composite oxide is not particularly limited as long as it can occlude and release lithium, but preferably contains titanium and / or lithium as a constituent component from the viewpoint of high current density charge / discharge characteristics.

As a carbonaceous material,
(1) natural graphite,
(2) Artificial carbonaceous material and artificial graphite material; carbonaceous material {for example, natural graphite, coal-based coke, petroleum-based coke, coal-based pitch, petroleum-based pitch, or those obtained by oxidizing these pitches, needle coke, pitch Coke and carbon materials partially graphitized, furnace black, acetylene black, pyrolysis products of organic substances such as pitch-based carbon fibers, carbonizable organic substances (for example, coal tar pitch from soft pitch to hard pitch, or dry distillation liquefaction Heavy oil such as coal, heavy oil of normal pressure, direct current heavy oil of reduced pressure residue, crude oil, cracked petroleum heavy oil such as ethylene tar produced during thermal decomposition of naphtha, acenaphthylene, decacyclene, Aromatic hydrocarbons such as anthracene and phenanthrene, N-ring compounds such as phenazine and acridine, thiophene, bithiophene, etc. Ring compounds, polyphenylenes such as biphenyl and terphenyl, polyvinyl chloride, polyvinyl alcohol, polyvinyl butyral, insolubilized products of these, organic polymers such as nitrogen-containing polyacrylonitrile, polypyrrole, sulfur-containing polythiophene, Organic polymers such as polystyrene, natural polymers such as polysaccharides represented by cellulose, lignin, mannan, polygalacturonic acid, chitosan, saccharose, thermoplastic resins such as polyphenylene sulfide and polyphenylene oxide, furfuryl alcohol resin, phenol -Thermosetting resins such as formaldehyde resin and imide resin) and their carbides or carbonizable organic substances in low molecular organic solvents such as benzene, toluene, xylene, quinoline, n-hexane, and the like Charcoal Carbonaceous material is heat treated one or more times things} in the range of from 400 to 3200 ° C.,
(3) a carbonaceous material in which the negative electrode active material layer is composed of at least two types of carbonaceous materials having different crystallinity and / or has an interface in contact with the different crystalline carbonaceous materials,
(4) a carbonaceous material in which the negative electrode active material layer is composed of carbonaceous materials having at least two or more different orientations and / or has an interface in contact with the carbonaceous materials having different orientations;
Is preferably a good balance between initial irreversible capacity and high current density charge / discharge characteristics.

[III-2-2-2-2. Structure of negative electrode, physical properties, preparation method]
Regarding the properties of the carbonaceous material, the negative electrode containing the carbonaceous material, the electrodeification method, the current collector, and the nonaqueous electrolyte secondary battery, any one of (1) to (19) below or It is desirable to satisfy multiple terms simultaneously.

(1) X-ray parameters For carbonaceous materials, the d value (interlayer distance) of the lattice plane (002 plane) determined by X-ray diffraction by the Gakushin method is preferably 0.335 nm or more, usually 0.360 nm. In the following, it is desired that the thickness is preferably 0.350 nm or less, more preferably 0.345 nm or less. Further, the crystallite size (Lc) of the carbonaceous material obtained by X-ray diffraction by the Gakushin method is preferably 1.0 nm or more, and more preferably 1.5 nm or more.

(2) Ash content The ash content in the carbonaceous material is 1% by mass or less, particularly 0.5% by mass or less, especially 0.1% by mass or less, and the lower limit is 1 ppm or more with respect to the total mass of the carbonaceous material. It is preferable that If the above range is exceeded, deterioration of battery performance due to reaction with the non-aqueous electrolyte during charge / discharge may not be negligible. Below this range, the manufacturing process requires a lot of time, energy and equipment for preventing contamination, which may increase costs.

(3) Volume-based average particle diameter The volume-based average particle diameter of the carbonaceous material is usually 1 μm or more, preferably 3 μm or more, more preferably a volume-based average particle diameter (median diameter) determined by a laser diffraction / scattering method. Is 5 μm or more, more preferably 7 μm or more. Moreover, an upper limit is 100 micrometers or less normally, Preferably it is 50 micrometers or less, More preferably, it is 40 micrometers or less, More preferably, it is 30 micrometers or less, Most preferably, it is 25 micrometers or less. If it falls below the above range, the irreversible capacity may increase, leading to loss of the initial battery capacity. On the other hand, when the above range is exceeded, when an electrode is produced by coating, a non-uniform coating surface tends to be formed, which may be undesirable in the battery production process.

  In the present invention, the volume-based average particle size is determined by dispersing carbon powder in a 0.2% by mass aqueous solution (about 10 mL) of polyoxyethylene (20) sorbitan monolaurate, which is a surfactant, and laser diffraction / scattering type particle size. It is defined by the median diameter measured using a distribution meter (for example, LA-700 manufactured by Horiba, Ltd.).

(4) Raman R value, Raman half-value width The Raman R value of the carbonaceous material measured using the argon ion laser Raman spectrum method is usually 0.01 or more, preferably 0.03 or more, more preferably 0.10 or more. The upper limit is 1.50 or less, preferably 1.2 or less, more preferably 1.0 or less, and still more preferably 0.50 or less. When the Raman R value is below this range, the crystallinity of the particle surface becomes too high, and there are cases where the number of sites where Li enters between layers decreases with charge / discharge. That is, charge acceptance may be reduced. In addition, when the negative electrode is densified by applying it to the current collector and then pressing it, the crystals are likely to be oriented in a direction parallel to the electrode plate, which may lead to a decrease in load characteristics. On the other hand, if it exceeds this range, the crystallinity of the particle surface will decrease, the reactivity with the non-aqueous electrolyte will increase, and the efficiency and gas generation may increase.

Further, the Raman half-width in the vicinity of 1580 cm ^{−1 of the} carbonaceous material is not particularly limited, but is usually 10 cm ⁻¹ or more, preferably 15 cm ⁻¹ or more, and the upper limit is usually 100 cm ⁻¹ or less, preferably 80 cm ⁻¹ or less. More preferably, it is 60 cm <^-1> or less, More preferably, it is the range of 40 cm <^-1> or less. When the Raman half width is less than this range, the crystallinity of the particle surface becomes too high, and there are cases where the number of sites where Li enters between layers decreases with charge and discharge. That is, charge acceptance may be reduced. In addition, when the negative electrode is densified by applying it to the current collector and then pressing it, the crystals are likely to be oriented in a direction parallel to the electrode plate, which may lead to a decrease in load characteristics. On the other hand, if it exceeds this range, the crystallinity of the particle surface will decrease, the reactivity with the non-aqueous electrolyte will increase, and the efficiency and gas generation may increase.

The Raman spectrum is measured using a Raman spectrometer (for example, a Raman spectrometer manufactured by JASCO Corporation), the sample is naturally dropped into the measurement cell and filled, and the sample surface in the cell is irradiated with an argon ion laser beam. The cell is rotated in a plane perpendicular to the laser beam. The obtained Raman spectrum, the intensity _{I A} of the peak _{P A} in the vicinity of 1580 cm ^-1, and measuring the intensity _{I B} of a peak _{P B} in the vicinity of 1360 cm ^-1, the intensity ratio R _{(R =} I B / _{I A} ) Is calculated and defined as the Raman R value of the carbonaceous material. Further, the half width of the peak P _A in the vicinity of 1580 cm ^-1 of the resulting Raman spectrum was measured, which is defined as the Raman half-value width of the carbonaceous material.

The Raman measurement conditions here are as follows.
Argon ion laser wavelength: 514.5nm
・ Laser power on the sample: 15-25mW
・ Resolution: 10-20cm ^-1
Measurement range: 1100 cm ^{−1 to} 1730 cm ⁻¹
・ Raman R value, Raman half width analysis: background processing,
-Smoothing processing: Simple average, 5 points of convolution

(5) BET specific surface area The specific surface area of the carbonaceous material measured using the BET method is usually 0.1 m ² / g or more, preferably 0.7 m ² / g or more, more preferably 1.0 m ² / g or more. More preferably, it is 1.5 m ² / g or more. An upper limit is 100 m < ² > / g or less normally, Preferably it is 25 m < ² > / g or less, More preferably, it is 15 m < ² > / g or less, More preferably, it is 10 m < ² > / g or less. If the value of the specific surface area is less than this range, the acceptability of lithium is likely to deteriorate during charging when used as a negative electrode material, and lithium is likely to precipitate on the electrode surface, which may reduce safety. On the other hand, if it exceeds this range, when used as a negative electrode material, the reactivity with the non-aqueous electrolyte increases, gas generation tends to increase, and a preferable battery may be difficult to obtain.

  The specific surface area according to the BET method is determined by using a surface area meter (for example, a fully automatic surface area measuring device manufactured by Riken Okura), preliminarily drying the sample at 350 ° C. for 15 minutes under a nitrogen flow, and then comparing the nitrogen relative to the atmospheric pressure. A value measured by a nitrogen adsorption BET one-point method using a gas flow method is used, using a nitrogen helium mixed gas that is accurately adjusted so that the pressure value becomes 0.3.

(6) Pore size distribution The pore size distribution of the carbonaceous material is determined by mercury porosimetry (mercury intrusion method). The pore diameter is 0.01 μm or more and 1 μm or less. The amount of unevenness due to steps, contact surfaces between particles, etc. is 0.01 mL / g or more, preferably 0.05 mL / g or more, more preferably 0.1 mL / g or more, and the upper limit is 0.6 mL / g or less, preferably Is 0.4 mL / g or less, more preferably 0.3 mL / g or less. If it exceeds this range, a large amount of binder may be required when forming an electrode plate. If it is less than the range, the high current density charge / discharge characteristics may be deteriorated, and the effect of mitigating the expansion / contraction of the electrode during charge / discharge may not be obtained.

  Further, the total pore volume corresponding to the pore diameter in the range of 0.01 μm to 100 μm is preferably 0.1 mL / g or more, more preferably 0.25 mL / g or more, still more preferably 0.4 mL / g or more, The upper limit is 10 mL / g or less, preferably 5 mL / g or less, more preferably 2 mL / g or less. If it exceeds this range, a large amount of binder may be required when forming an electrode plate. If it is less than that, it may not be possible to obtain the effect of dispersing the thickener or the binder during the electrode plate formation.

  The average pore diameter is preferably 0.05 μm or more, more preferably 0.1 μm or more, further preferably 0.5 μm or more, and the upper limit is 50 μm or less, preferably 20 μm or less, more preferably 10 μm or less. Beyond this range, a large amount of binder may be required. If it is less, the high current density charge / discharge characteristics may deteriorate.

  The average pore diameter is preferably 0.05 μm or more, more preferably 0.1 μm or more, further preferably 0.5 μm or more, and the upper limit is 50 μm or less, preferably 20 μm or less, more preferably 10 μm or less. Beyond this range, a large amount of binder may be required. If it is less, the high current density charge / discharge characteristics may deteriorate.

  As an apparatus for mercury porosimetry, a mercury porosimeter (Autopore 9520: manufactured by Micromeritex Corporation) is used. About 0.2 g of a sample is sealed in a powder cell and pretreated by deaeration for 10 minutes at room temperature under vacuum (50 μmHg or less). Subsequently, the pressure is reduced to 4 psia (about 28 kPa), mercury is introduced, the pressure is increased stepwise from 4 psia (about 28 kPa) to 40000 psia (about 280 MPa), and then the pressure is reduced to 25 psia (about 170 kPa). The number of steps at the time of pressure increase is 80 points or more, and the mercury intrusion amount is measured after an equilibration time of 10 seconds in each step. From the mercury intrusion curve thus obtained, the pore size distribution is calculated using the Washburn equation. The surface tension (γ) of mercury is 485 dyne / cm, and the contact angle (ψ) is 140 °. As the average pore diameter, the pore diameter when the cumulative pore volume is 50% is used. Note that 1 dyne = 10 μN (micro Newton).

(7) Circularity Using circularity as the degree of sphericity of the carbonaceous material, the circularity of particles having a particle size in the range of 3 to 40 μm is preferably 0.1 or more, particularly preferably 0.5 or more. Preferably it is 0.8 or more, more preferably 0.85 or more, and most preferably 0.9 or more. High circularity is preferable because high current density charge / discharge characteristics are improved. The circularity is defined by the following formula. When the circularity is 1, a theoretical sphere is obtained.
Circularity = (perimeter of equivalent circle having the same area as the particle projection shape) / (actual circumference of particle projection shape)

  As the value of the circularity, for example, a flow type particle image analyzer (for example, FPIA manufactured by Sysmex Industrial Co., Ltd.) is used, and about 0.2 g of a sample is mixed with polyoxyethylene (20) sorbitan monolaurate as a surfactant. Particles having a detection range of 0.6 to 400 μm and a particle size in the range of 3 to 40 μm after being dispersed in a 0.2 mass% aqueous solution (about 50 mL) and irradiated with an ultrasonic wave of 28 kHz for 1 minute at an output of 60 W Use the value measured for.

  The method for improving the degree of circularity is not particularly limited, but a spheroidized sphere is preferable because the shape of the interparticle void when the electrode body is formed is preferable. Examples of spheroidizing treatment include a method of mechanically approaching a sphere by applying a shearing force and a compressive force, a mechanical / physical processing method of granulating a plurality of fine particles by the binder or the adhesive force of the particles themselves, etc. Is mentioned.

(8) True density The true density of the carbonaceous material is usually 1.4 g / cm ³ or more, preferably 1.6 g / cm ³ or more, more preferably 1.8 g / cm ³ or more, and still more preferably 2.0 g / cm ^3. cm ³ and the upper limit is 2.26 g / cm ³ or less. The upper limit is the theoretical value of graphite. Below this range, the crystallinity of the carbon is too low and the initial irreversible capacity may increase. In the present invention, the true density is defined by a value measured by a liquid phase substitution method (pycnometer method) using butanol.

(9) Tap density The tap density of the carbonaceous material is usually 0.1 g / cm ³ or more, preferably 0.5 g / cm ³ or more, more preferably 0.7 g / cm ³ or more, and particularly preferably 1 g / cm ^3. That's it. The upper limit is preferably 2 g / cm ³ or less, more preferably 1.8 g / cm ³ or less, and particularly preferably 1.6 g / cm ³ or less. When the tap density is below this range, the packing density is difficult to increase when used as a negative electrode, and a high-capacity battery may not be obtained. On the other hand, if it exceeds this range, there are too few voids between the particles in the electrode, it becomes difficult to ensure conductivity between the particles, and it may be difficult to obtain preferable battery characteristics. The tap density is measured and defined by the same method as that described in the section of the positive electrode active material.

(10) Orientation ratio The orientation ratio of the carbonaceous material is usually 0.005 or more, preferably 0.01 or more, more preferably 0.015 or more, and the upper limit is theoretically 0.67 or less. Below this range, the high-density charge / discharge characteristics may deteriorate.
The orientation ratio is measured as follows by X-ray diffraction after pressure-molding the sample.
X-ray diffraction is performed by setting a molded body obtained by filling 0.47 g of a sample into a molding machine having a diameter of 17 mm and compressing it at 600 kgf / cm ^{2 so} that it is flush with the surface of the measurement sample holder. Measure. A ratio represented by (110) diffraction peak intensity / (004) diffraction peak intensity is calculated from the (110) diffraction and (004) diffraction peak intensities of the obtained carbon, and defined as the orientation ratio of the active material. Note that 1 kgf = 9.80665N.

The X-ray diffraction measurement conditions here are as follows. “2θ” indicates a diffraction angle.
・ Target: Cu (Kα ray) graphite monochromator ・ Slit:
Divergence slit = 0.5 degree, light receiving slit = 0.15 mm, scattering slit = 0.5 degree. Measurement range and step angle / measurement time:
(110) plane: 75 degrees ≦ 2θ ≦ 80 degrees 1 degree / 60 seconds (004) plane: 52 degrees ≦ 2θ ≦ 57 degrees 1 degree / 60 seconds

(11) Aspect ratio (powder)
The aspect ratio is theoretically 1 or more, and the upper limit is usually 10 or less, preferably 8 or less, more preferably 5 or less. If the upper limit is exceeded, streaking or a uniform coated surface may not be obtained during electrode plate formation, and the high current density charge / discharge characteristics may deteriorate.

  The aspect ratio is expressed as A / B, where the longest diameter A of the carbonaceous material particles when observed three-dimensionally and the shortest diameter B perpendicular to the diameter A. The carbon particles are observed with a scanning electron microscope capable of magnifying observation. Arbitrary 50 graphite particles fixed on the end face of a metal having a thickness of 50 microns or less are selected, and the stage on which the sample is fixed is rotated and tilted, and A and B are measured. Find the average value.

(12) Sub-material mixing “Sub-material mixing” means that two or more carbonaceous materials having different properties are contained in the negative electrode and / or the negative electrode active material. The properties described here include one or more of X-ray diffraction parameters, median diameter, aspect ratio, BET specific surface area, orientation ratio, Raman R value, tap density, true density, pore distribution, circularity, and ash content. Show the characteristics.

  Particularly preferred embodiments include that the volume-based particle size distribution is not symmetrical when the median diameter is centered, that two or more carbonaceous materials having different Raman R values are contained, and the X-ray parameters are It is different.

  As an example of the effect, carbonaceous materials such as natural graphite, graphite such as artificial graphite, carbon black such as acetylene black, and amorphous carbon such as needle coke are contained as a conductive agent. It can be reduced. These may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and a ratio. When used as a conductive agent, the concentration of the carbonaceous material used as the conductive agent in the negative electrode active material is usually 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 0.6% by mass. The upper limit is usually 45% by mass or less, preferably 40% by mass or less. Below this range, the effect of improving conductivity may be difficult to obtain. If it exceeds, the initial irreversible capacity may increase.

(13) Electrode production The electrode may be produced by a conventional method. For example, it is formed by adding a binder, a solvent, and, if necessary, a thickener, a conductive material, a filler, etc. to a negative electrode active material to form a slurry, which is applied to a current collector, dried and then pressed. Can do. The thickness of the negative electrode active material layer per side in the stage immediately before the non-aqueous electrolyte injection process of the battery is usually 15 μm or more, preferably 20 μm or more, more preferably 30 μm or more, and the upper limit is 150 μm or less, preferably 120 μm. Hereinafter, it is more preferably 100 μm or less. If it exceeds this range, the non-aqueous electrolyte solution hardly penetrates to the vicinity of the current collector interface, and thus the high current density charge / discharge characteristics may deteriorate. On the other hand, below this range, the volume ratio of the current collector to the negative electrode active material increases, and the battery capacity may decrease. Further, the negative electrode active material may be roll-formed to form a sheet electrode, or may be formed into a pellet electrode by compression molding.

(14) Current collector Any known current collector can be used. Examples of the current collector for the negative electrode include metal materials such as copper, nickel, stainless steel, and nickel-plated steel. Of these, copper is particularly preferable from the viewpoint of ease of processing and cost. When the current collector is a metal material, examples of the shape of the current collector include metal foil, metal cylinder, metal coil, metal plate, metal thin film, expanded metal, punch metal, and foam metal. Among them, a metal thin film is preferable, a copper foil is more preferable, and a rolled copper foil by a rolling method and an electrolytic copper foil by an electrolytic method are more preferable, and both can be used as a current collector. When the thickness of the copper foil is less than 25 μm, a copper alloy (phosphor bronze, titanium copper, Corson alloy, Cu—Cr—Zr alloy, etc.) having higher strength than pure copper can be used.

  A current collector made of a copper foil produced by a rolling method is suitable for use in a small cylindrical battery because the copper crystals are arranged in the rolling direction so that the negative electrode is hard to crack even if it is rounded sharply or rounded at an acute angle. be able to. On the other hand, the electrolytic copper foil, for example, immerses a metal drum in a non-aqueous electrolyte solution in which copper ions are dissolved, and causes the copper to precipitate on the surface of the drum by flowing an electric current while rotating the drum. It can be obtained by peeling off. Note that copper may be deposited on the surface of the rolled copper foil by an electrolytic method. Further, one or both surfaces of the copper foil may be subjected to a roughening treatment or a surface treatment (for example, a chromate treatment having a thickness of about several nm to 1 μm, a base treatment such as Ti).

The following physical properties are desired for the current collector substrate.
(14-1) Average surface roughness (Ra)
The average surface roughness (Ra) of the negative electrode active material thin film forming surface of the current collector substrate defined by the method described in JIS B0601-1994 is not particularly limited, but is usually 0.05 μm or more, preferably 0.1 μm or more. The thickness is particularly preferably 0.15 μm or more, usually 1.5 μm or less, preferably 1.3 μm or less, particularly preferably 1.0 μm or less. By setting the average surface roughness (Ra) of the current collector substrate within the range between the lower limit and the upper limit described above, good charge / discharge cycle characteristics can be expected. By setting it to the above lower limit or more, the area of the interface with the negative electrode active material thin film is increased, and the adhesion with the negative electrode active material thin film is improved. The upper limit of the average surface roughness (Ra) is not particularly limited, but those having an average surface roughness (Ra) exceeding 1.5 μm are generally difficult to obtain as foils having a practical thickness as a battery. 1.5 μm or less is preferable.

(14-2) Tensile strength The tensile strength of the current collector substrate is not particularly limited, but is usually 100 N / mm ² or more, preferably 250 N / mm ² or more, more preferably 400 N / mm ² or more, and particularly preferably 500 N / mm. mm ² or more. The tensile strength is obtained by dividing the maximum tensile force required until the test piece breaks by the cross-sectional area of the test piece. The tensile strength in the present invention is measured by the same apparatus and method as the elongation rate. If the current collector substrate has a high tensile strength, cracking of the current collector substrate due to expansion / contraction of the negative electrode active material thin film accompanying charging / discharging can be suppressed, and good cycle characteristics can be obtained.

(14-3) 0.2% proof stress of 0.2% proof stress current collector substrate is not particularly limited, normally 30 N / mm ² or more, preferably 150 N / mm ² or more, particularly preferably 300N / mm ² or more It is. The 0.2% proof stress is the magnitude of the load necessary to give a plastic (permanent) strain of 0.2%. It means that The 0.2% proof stress is measured by the same apparatus and method as the elongation rate. If the current collector substrate has a high 0.2% proof stress, plastic deformation of the current collector substrate due to expansion / contraction of the negative electrode active material thin film accompanying charging / discharging can be suppressed, and good cycle characteristics can be obtained. Can do.

  Although the thickness of a metal thin film is arbitrary, it is 1 micrometer or more normally, Preferably it is 3 micrometers or more, More preferably, it is 5 micrometers or more. Moreover, an upper limit is 1 mm or less normally, Preferably it is 100 micrometers or less, More preferably, it is 30 micrometers or less. If the thickness is less than 1 μm, the strength may be reduced, and application may be difficult. On the other hand, when the thickness exceeds 100 μm, the shape of the electrode such as winding may be deformed. The metal thin film may be mesh.

(15) Ratio of thickness of current collector and negative electrode active material layer The ratio of the thickness of current collector and negative electrode active material layer is not particularly limited, but (one-sided negative electrode active material immediately before non-aqueous electrolyte injection) (Layer thickness) / (current collector thickness) is preferably 150 or less, particularly preferably 20 or less, more preferably 10 or less, and the lower limit is preferably 0.1 or more, particularly preferably 0. The range is 4 or more, more preferably 1 or more. Above this range, the current collector may generate heat due to Joule heat during high current density charge / discharge. Below this range, the volume ratio of the current collector to the negative electrode active material increases and the battery capacity may decrease.

(16) Electrode density The electrode structure when the negative electrode active material is made into an electrode is not particularly limited, but the density of the negative electrode active material present on the current collector is preferably 1 g / cm ³ or more, more preferably 1.2 g / cm ³ , more preferably 1.3 g / cm ³ or more, and the upper limit is 2 g / cm ³ or less, preferably 1.9 g / cm ³ or less, more preferably 1.8 g / cm ³ or less, More preferably, it is the range of 1.7 g / cm ³ or less. When exceeding this range, the negative electrode active material particles are destroyed, resulting in an increase in initial irreversible capacity and a deterioration in high current density charge / discharge characteristics due to a decrease in the permeability of the non-aqueous electrolyte near the current collector / negative electrode active material interface. There is. On the other hand, the conductivity between the negative electrode active materials decreases, the battery resistance increases, and the capacity per unit volume may decrease.

(17) Binder The binder for binding the negative electrode active material is not particularly limited as long as it is a material that is stable with respect to the non-aqueous electrolyte and the solvent used during electrode production. Specifically, resin-based polymers such as polyethylene, polypropylene, polyethylene terephthalate, polymethyl methacrylate, polyimide, aromatic polyamide, cellulose, nitrocellulose; SBR (styrene-butadiene rubber), isoprene rubber, butadiene rubber, fluororubber, Rubber polymers such as NBR (acrylonitrile / butadiene rubber) and ethylene / propylene rubber; styrene / butadiene / styrene block copolymer or hydrogenated product thereof; EPDM (ethylene / propylene / diene terpolymer), styrene / Thermoplastic elastomeric polymers such as ethylene / butadiene / styrene copolymers, styrene / isoprene / styrene block copolymers or hydrogenated products thereof; syndiotactic-1,2-polybutadiene, polyvinyl acetate, Soft resinous polymers such as tylene / vinyl acetate copolymer, propylene / α-olefin copolymer; polyvinylidene fluoride, polytetrafluoroethylene, fluorinated polyvinylidene fluoride, polytetrafluoroethylene / ethylene copolymer, etc. Fluoropolymers; polymer compositions having ionic conductivity of alkali metal ions (especially lithium ions). These may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and a ratio.

  The solvent for forming the slurry is not particularly limited as long as it is a solvent capable of dissolving or dispersing the negative electrode active material, the binder, and the thickener and conductive agent used as necessary. Alternatively, either an aqueous solvent or an organic solvent may be used. Examples of the aqueous solvent include water, alcohol and the like, and examples of the organic solvent include N-methylpyrrolidone (NMP), dimethylformamide, dimethylacetamide, methyl ethyl ketone, cyclohexanone, methyl acetate, methyl acrylate, diethyltriamine, N -N-dimethylaminopropylamine, tetrahydrofuran (THF), toluene, acetone, diethyl ether, dimethylacetamide, hexamethylphosphalamide, dimethyl sulfoxide, benzene, xylene, quinoline, pyridine, methylnaphthalene, hexane, etc. .

  In particular, when an aqueous solvent is used, a dispersant or the like is added to the thickener, and a slurry such as SBR is used to make a slurry. In addition, these may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and a ratio.

  The ratio of the binder to the negative electrode active material is preferably 0.1% by mass or more, particularly preferably 0.5% by mass or more, more preferably 0.6% by mass or more, and the upper limit is usually 20% by mass or less. Preferably it is 15 mass% or less, More preferably, it is 10 mass% or less, More preferably, it is the range of 8 mass% or less. When it exceeds this range, the binder ratio in which the binder amount does not contribute to the battery capacity increases, and the battery capacity may be reduced. On the other hand, if it is lower, the strength of the negative electrode may be reduced.

  In particular, when the main component contains a rubbery polymer typified by SBR, the ratio of the binder to the negative electrode active material is 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 0%. The upper limit is usually 5% by mass or less, preferably 3% by mass or less, and more preferably 2% by mass or less. In addition, when the main component contains a fluorine-based polymer typified by polyvinylidene fluoride, the ratio to the negative electrode active material is 1% by mass or more, preferably 2% by mass or more, more preferably 3% by mass or more. The upper limit is 15% by mass or less, preferably 10% by mass or less, and more preferably 8% by mass or less.

  A thickener is usually used to adjust the viscosity of the slurry. The thickener is not particularly limited, and specific examples include carboxymethyl cellulose, methyl cellulose, hydroxymethyl cellulose, ethyl cellulose, polyvinyl alcohol, oxidized starch, phosphorylated starch, casein, and salts thereof. These may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and a ratio.

  Furthermore, when using a thickener, the ratio of the thickener to the negative electrode active material is 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 0.6% by mass or more, As an upper limit, it is 5 mass% or less, Preferably it is 3 mass% or less, More preferably, it is the range of 2 mass% or less. Below this range, applicability may be significantly reduced. When it exceeds, the ratio of the negative electrode active material to the negative electrode active material layer may decrease, and the battery capacity may decrease or the resistance between the negative electrode active materials may increase.

(18) Electrode orientation ratio The electrode orientation ratio is preferably 0.001 or more, particularly preferably 0.005 or more, more preferably 0.01 or more, and the upper limit is 0.67 or less, which is a theoretical value. Below this range, the high-density charge / discharge characteristics may deteriorate.
The measurement of the electrode plate orientation ratio is as follows. About the negative electrode after pressing to the target density, the negative electrode active material orientation ratio of the electrode is measured by X-ray diffraction. The specific method is not particularly limited, but as a standard method, peak separation is performed by fitting the peaks of (110) and (004) diffraction of carbon by X-ray diffraction using asymmetric Pearson VII as a profile function. The integrated intensities of the peaks of (110) diffraction and (004) diffraction are calculated. From the obtained integrated intensity, a ratio expressed by (110) diffraction integrated intensity / (004) diffraction integrated intensity is calculated and defined as the negative electrode active material orientation ratio of the electrode.

The X-ray diffraction measurement conditions here are as follows. “2θ” indicates a diffraction angle.
-Target: Cu (Kα ray) graphite monochromator-Slit: Divergence slit = 1 degree, Receiving slit = 0.1 mm, Scattering slit = 1 degree-Measurement range and step angle / measurement time:
(110) plane: 76.5 degrees ≦ 2θ ≦ 78.5 degrees 0.01 degrees / 3 seconds (004) plane: 53.5 degrees ≦ 2θ ≦ 56.0 degrees 0.01 degrees / 3 seconds Sample preparation: Fix the electrode to the glass plate with double-sided tape with a thickness of 0.1 mm

(19) Impedance The resistance of the negative electrode when charged from the discharged state to 60% of the nominal capacity is preferably 100Ω or less, particularly preferably 50Ω or less, more preferably 20Ω or less, and / or the double layer capacity is 1 × 10 ^{− 6} F or more is preferable, particularly preferably 1 × 10 ⁻⁵ F, and more preferably 1 × 10 ⁻⁴ F. Within this range, the output characteristics are good and preferable.

The resistance and double layer capacity of the negative electrode are measured by the following procedure. The non-aqueous electrolyte secondary battery to be measured is charged at a current value capable of charging a nominal capacity in 5 hours, then maintained in a state where it is not charged / discharged for 20 minutes, and then a current value capable of discharging the nominal capacity in 1 hour. The capacity when discharged at 80% or more of the nominal capacity is used. For the non-aqueous electrolyte secondary battery in the above-mentioned discharge state, the nominal capacity is charged to 60% of the nominal capacity at a current value that can be charged in 5 hours, and the non-aqueous electrolyte secondary battery is immediately put into a glove box under an argon gas atmosphere. Move in. Here, the non-aqueous electrolyte secondary battery is quickly disassembled and taken out in a state where the negative electrode is not discharged or short-circuited, and if it is a double-sided coated electrode, the negative electrode active material on one side is peeled off without damaging the negative electrode active material on the other side, Two negative electrodes are punched into 12.5 mmφ, and are opposed to each other so that the negative electrode active material surface does not shift through a separator. 60μL of non-aqueous electrolyte used in the battery was dropped between the separator and both negative electrodes, and kept in close contact with the outside air, and the current collector of both negative electrodes was made conductive and the AC impedance method was carried out. To do. The measurement is performed at a temperature of 25 ° C., and the complex impedance is measured in a frequency band of 10 ⁻² to 10 ⁵ Hz. The surface resistance (R) is obtained by approximating the arc of the negative resistance component of the obtained Cole-Cole plot with a semicircle. And double layer capacity | capacitance (Cdl) is calculated | required.

  The area of the negative electrode plate is not particularly limited, but is designed to be slightly larger than the opposing positive electrode plate so that the positive electrode plate does not protrude from the negative electrode plate. From the viewpoint of suppressing the cycle life of repeated charge and discharge and deterioration due to high temperature storage, it is preferable to make it as close as possible to the area equal to the positive electrode because the characteristics are improved by increasing the proportion of the electrodes that work more uniformly and effectively. In particular, when the electrode is used at a large current, the design of the electrode area is important.

  The thickness of the negative electrode plate is designed according to the positive electrode plate to be used and is not particularly limited, but the thickness of the composite layer obtained by subtracting the thickness of the metal foil of the core is usually 15 μm or more, Preferably it is 20 micrometers or more, More preferably, it is 30 micrometers or more, and an upper limit is 150 micrometers or less, Preferably it is 120 micrometers or less, More preferably, it is 100 micrometers or less.

[III-2-2-3. Non-aqueous electrolyte]
The non-aqueous electrolyte used for the non-aqueous electrolyte secondary battery of the present invention will be described below. The non-aqueous electrolyte used in the non-aqueous electrolyte secondary battery of the present invention contains a lithium salt and a non-aqueous solvent that dissolves the lithium salt.

[III-2-2-3-1. Lithium salt]]
The lithium salt is not particularly limited as long as it is known to be used as an electrolyte of a non-aqueous electrolyte solution for a non-aqueous electrolyte secondary battery, and examples thereof include the following.

(1) Inorganic lithium salt:
Inorganic fluoride salts such as LiPF ₆ , LiBF ₄ , LiAsF ₆ , LiSbF ₆ ; perhalogenates such as LiClO ₄ , LiBrO ₄ , LiIO ₄ ; inorganic chloride salts such as LiAlCl ₄ .
(2) Fluorine-containing organic lithium salt:
Perfluoroalkane sulfonates such as LiCF ₃ SO ₃ ; LiN (CF ₃ SO ₂ ) ₂ , LiN (CF ₃ CF ₂ SO ₂ ) ₂ , LiN (CF ₃ SO ₂ ) (C ₄ F ₉ SO ₂ ), etc. Perfluoroalkanesulfonylimide salt; perfluoroalkanesulfonylmethide salt such as LiC (CF ₃ SO ₂ ) ₃ ; Li [PF ₅ (CF ₂ CF ₂ CF ₃ )], Li [PF ₄ (CF ₂ CF ₂ CF ₃ ) ₂ ], Li [PF ₃ (CF ₂ CF ₂ CF ₃ ) ₃ ], Li [PF ₅ (CF ₂ CF ₂ CF ₂ CF ₃ )], Li [PF ₄ (CF ₂ CF ₂ CF ₂ CF ₃ ) ₂ ], Fluoroalkyl fluorophosphates such as Li [PF ₃ (CF ₂ CF ₂ CF ₂ CF ₃ ) ₃ ] and the like.
(3) Oxalatoborate salt:
Lithium difluorooxalatoborate, lithium bis (oxalato) borate and the like.

These may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and ratios.
Among these, LiPF ₆ , LiBF _{4, and the} like are preferable, and LiPF ₆ is particularly preferable when comprehensively judging solubility in a non-aqueous solvent, charge / discharge characteristics, output characteristics, cycle characteristics, and the like in the case of a secondary battery. .

  The concentration of the lithium salt in the nonaqueous electrolytic solution is not particularly limited, but is usually 0.3 mol / L or more, preferably 0.6 mol / L or more, more preferably 0.7 mol / L or more. Moreover, the upper limit is 2 mol / L or less normally, Preferably it is 1.8 mol / L or less, More preferably, it is 1.7 mol / L or less. If the concentration is too low, the electrical conductivity of the non-aqueous electrolyte may be insufficient. On the other hand, if the concentration is too high, the electrical conductivity may decrease due to an increase in viscosity. Battery performance may be reduced.

  Further, the non-aqueous electrolyte preferably contains a fluorine-containing lithium salt as the lithium salt. The concentration of the fluorine-containing lithium salt in the non-aqueous electrolyte solution is not particularly limited, but is preferably 0.5 mol / L or more, particularly preferably 0.7 mol / L or more. Moreover, the upper limit is preferably 2 mol / L or less, particularly preferably 1.7 mol / L or less. If the concentration is too low, the electrical conductivity of the non-aqueous electrolyte may be insufficient. On the other hand, if the concentration is too high, the electrical conductivity will decrease due to an increase in viscosity, resulting in a non-aqueous electrolyte secondary battery. Performance may be degraded.

Lithium salts may be used singly or in combination of two or more in any combination and ratio, but a preferred example when two or more lithium salts are used in combination is LiPF ₆ and LiBF _4. In this case, the proportion of LiBF _{4 in} the total of both is particularly preferably 0.01% by mass or more and 20% by mass or less, more preferably 0.1% by mass or more and 5% by mass. More preferably, it is as follows. Another preferred example is the combined use of an inorganic fluoride salt and a perfluoroalkanesulfonylimide salt. In this case, the proportion of the inorganic fluoride salt in the total of both is 70% by mass or more and 99% by mass. % Or less, particularly preferably 80% by mass or more and 98% by mass or less. The combined use of both has the effect of suppressing deterioration due to high temperature storage.

[III-2-2-3-2. Nonaqueous solvent]
As the non-aqueous solvent, it can be appropriately selected from those conventionally proposed as solvents for non-aqueous electrolyte solutions. For example, the following are mentioned.

(1) Cyclic carbonate:
As for carbon number of the alkylene group which comprises a cyclic carbonate, 2-6 are preferable, Most preferably, it is 2-4. Specific examples include ethylene carbonate, propylene carbonate, butylene carbonate, and the like. Of these, ethylene carbonate and propylene carbonate are preferable.

(2) Chain carbonate:
As the chain carbonate, dialkyl carbonate is preferable, and the number of carbon atoms of the alkyl group is preferably 1 to 5, and particularly preferably 1 to 4, respectively. Specifically, for example, symmetrical chain carbonates such as dimethyl carbonate, diethyl carbonate, and di-n-propyl carbonate, and asymmetric chain carbonates such as ethyl methyl carbonate, methyl-n-propyl carbonate, and ethyl-n-propyl carbonate. And dialkyl carbonates. Of these, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate are preferable.

(3) Cyclic ester:
Examples of the cyclic ester include γ-butyrolactone and γ-valerolactone.
(4) Chain ester:
Examples of the chain ester include methyl acetate, ethyl acetate, propyl acetate, and methyl propionate.

(5) Cyclic ether:
Examples of the cyclic ether include tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran and the like.
(6) Chain ether:
Examples of the chain ether include dimethoxyethane and dimethoxymethane.
(7) Sulfur-containing organic solvent:
Examples of the sulfur-containing organic solvent include sulfolane and diethyl sulfone.

  These may be used alone or in combination of two or more, but it is preferable to use two or more compounds in combination. For example, it is preferable to use a high dielectric constant solvent such as cyclic carbonates and cyclic esters in combination with a low viscosity solvent such as chain carbonates and chain esters.

  One preferred combination of non-aqueous solvents is a combination mainly composed of cyclic carbonates and chain carbonates. Among them, the total of the cyclic carbonates and the chain carbonates in the nonaqueous solvent is 85% by volume or more, preferably 90% by volume or more, and more preferably 95% by volume or more. Further, the capacity of the cyclic carbonate with respect to the total of the cyclic carbonate and the chain carbonate is 5% or more, preferably 10% or more, more preferably 15% or more, usually 50% or less, preferably 35% or less, More preferred is 30% or less, and further preferred is 25% or less. It is particularly preferred that the above preferred volume range of the total amount of carbonates occupying the entire non-aqueous solvent is combined with the preferred above volume range of cyclic carbonates relative to cyclic and chain carbonates.

  Specific examples of preferred combinations of cyclic carbonates and chain carbonates include ethylene carbonate and dimethyl carbonate, ethylene carbonate and diethyl carbonate, ethylene carbonate and ethyl methyl carbonate, ethylene carbonate and dimethyl carbonate and diethyl carbonate, ethylene carbonate and dimethyl carbonate And ethyl methyl carbonate, ethylene carbonate, diethyl carbonate, and ethyl methyl carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate. A combination in which propylene carbonate is further added to the combination of these ethylene carbonates and chain carbonates is also a preferable combination. In the case of containing propylene carbonate, the volume ratio of ethylene carbonate to propylene carbonate is preferably 99: 1 to 40:60, particularly preferably 95: 5 to 50:50.

  Among these, those containing asymmetric chain carbonates are more preferable, particularly ethylene carbonate, dimethyl carbonate and ethyl methyl carbonate, ethylene carbonate, diethyl carbonate and ethyl methyl carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate and ethyl. Those containing ethylene carbonate such as methyl carbonate, symmetric chain carbonates, and asymmetric chain carbonates are preferred because of a good balance between cycle characteristics and large current discharge characteristics. Among these, those in which the asymmetric chain carbonate is ethyl methyl carbonate are preferable, and the alkyl group constituting the dialkyl carbonate preferably has 1 to 2 carbon atoms.

  Other examples of preferred non-aqueous solvents are those containing chain esters. In particular, those containing a chain ester in the mixed solvent of cyclic carbonates and chain carbonates are preferable from the viewpoint of improving low-temperature characteristics of the battery, and as the chain esters, methyl acetate and ethyl acetate are particularly preferable. . The capacity of the chain ester in the non-aqueous solvent is usually 5% or more, preferably 8% or more, more preferably 15% or more, usually 50% or less, preferably 35% or less, more preferably 30% or less, More preferably, it is 25% or less.

Examples of other preferable non-aqueous solvents include one organic solvent selected from the group consisting of ethylene carbonate, propylene carbonate, γ-butyrolactone and γ-valerolactone, or two or more organic solvents selected from the group. The mixed solvent becomes 60% by volume or more of the whole. Such a mixed solvent preferably has a flash point of 50 ° C. or higher, and particularly preferably has a flash point of 70 ° C. or higher. A non-aqueous electrolyte using this solvent reduces evaporation of the solvent and leakage even when used at high temperatures.
Among them, the amount of γ-butyrolactone in the nonaqueous solvent is 60% by volume or more, and the total of ethylene carbonate and γ-butyrolactone in the nonaqueous solvent is 80% by volume or more, preferably 90% by volume or more. And the volume ratio of ethylene carbonate to γ-butyrolactone is 5:95 to 45:55, or the total of ethylene carbonate and propylene carbonate in the non-aqueous solvent is 80% by volume or more, preferably 90% When the ratio of ethylene carbonate to propylene carbonate is 30:70 to 60:40, the balance between cycle characteristics and large current discharge characteristics is generally improved.

[III-2-2-3-3. Specific compound]
The non-aqueous electrolyte solution in the non-aqueous electrolyte secondary battery of the present invention further includes a cyclic siloxane compound represented by general formula (1), a fluorosilane compound represented by general formula (2), and general formula (3). One or more selected from the group consisting of a compound represented by formula (1), a compound having an SF bond in the molecule, nitrate, nitrite, monofluorophosphate, difluorophosphate, acetate and propionate Compounds (hereinafter, these may be abbreviated as “specific compounds”) may be contained in any amount as necessary.

［一般式（１）中、Ｒ^１及びＲ^２は互いに同一であっても異なっていてもよい炭素数１〜１２の有機基を表し、ｎは３〜１０の整数を表す。］

[In General Formula (1), R ¹ and R ² represent the same or different organic group having 1 to 12 carbon atoms, and n represents an integer of 3 to 10. ]

［一般式（２）中、Ｒ^３〜Ｒ^５は互いに同一であっても異なっていてもよい炭素数１〜１２の有機基を表し、ｘは１〜３の整数を表し、ｐ、ｑ及びｒはそれぞれ０〜３の整数を表し、１≦ｐ＋ｑ＋ｒ≦３である。］

[In General Formula (2), R ^{3 to} R ⁵ represent an organic group having 1 to 12 carbon atoms which may be the same or different from each other, x represents an integer of 1 to 3, p, q and Each r represents an integer of 0 to 3, and 1 ≦ p + q + r ≦ 3. ]

［一般式（３）中、Ｒ^６〜Ｒ^８は互いに同一であっても異なっていてもよい炭素数１〜１２の有機基を表し、ＡはＨ、Ｃ、Ｎ、Ｏ、Ｆ、Ｓ、Ｓｉ及び／又はＰから構成される基を表す。］

[In General Formula (3), R ^{6 to} R ⁸ represent an organic group having 1 to 12 carbon atoms which may be the same as or different from each other, and A represents H, C, N, O, F, S, Represents a group composed of Si and / or P; ]

A non-aqueous electrolyte solution containing at least one lithium salt and at least one of the above specific compounds in the non-aqueous solvent (mixed solvent) is a cycle characteristic and a high-temperature storage characteristic (especially high-temperature storage) of a battery produced using the non-aqueous electrolyte. The remaining balance and the high load discharge capacity) and the suppression of gas generation are improved, which is preferable.
In particular, it is considered that these specific compounds can suppress side reactions with the electrolytic solution and the like by adsorbing on the surface of the positive electrode active material or the surface of the metal material. By suppressing the side reaction on the surface of the positive electrode active material, gas generation can be suppressed, and gas generation at the time of battery breakdown or internal short circuit can be suppressed.

Further, it is considered preferable for use in a large battery that the side life on the surface of the positive electrode active material is suppressed to improve battery life, output, and safety during overcharge. Due to the suppression of side reactions on the surface of the metal material, an increase in the DC resistance component is suppressed during long-term use even when a simple welding method with low resistance is used to connect the current collecting tab and the terminal. It is considered preferable for use in a large battery. Furthermore, lowering the reaction resistance of the positive electrode is effective and preferable in order to further improve the output in a battery designed for high output in terms of battery shape, positive electrode area, and the like.
By containing these specific compounds, high safety can be ensured even in the case of a high output or large battery.

Next, details of these specific compounds will be described.
[Cyclic siloxane compound represented by the general formula (1)]
R ¹ and R ² in the cyclic siloxane compound represented by the general formula (1) are C 1-12 organic groups which may be the same or different from each other. Examples of R ¹ and R ² include a chain alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group; a cyclohexyl group and a norbornyl group Cyclic alkyl groups such as groups; alkenyl groups such as vinyl groups, 1-propenyl groups, allyl groups, butenyl groups, 1,3-butadienyl groups; alkynyl groups such as ethynyl groups, propynyl groups, butynyl groups; trifluoromethyl groups, etc. An alkyl group having a saturated heterocyclic group such as 3-pyrrolidinopropyl group; an aryl group such as a phenyl group optionally having an alkyl substituent; an aralkyl such as a phenylmethyl group or a phenylethyl group Groups; trialkylsilyl groups such as trimethylsilyl groups; trialkylsiloxy groups such as trimethylsiloxy groups; It is.

Of these, organic groups having 1 to 6 carbon atoms are preferred because those having fewer carbon atoms are more likely to exhibit characteristics. Alkenyl groups act on non-aqueous electrolytes and coatings on electrode surfaces to improve input / output characteristics, and aryl groups have the effect of capturing radicals generated in the battery during charge and discharge to improve overall battery performance. Therefore, it is preferable. Accordingly, R ¹ and R ² are particularly preferably a methyl group, a vinyl group, or a phenyl group.

  In general formula (1), n represents an integer of 3 to 10, but an integer of 3 to 6 is preferable, and 3 or 4 is particularly preferable.

  Examples of the cyclic siloxane compound represented by the general formula (1) include hexamethylcyclotrisiloxane, hexaethylcyclotrisiloxane, hexaphenylcyclotrisiloxane, 1,3,5-trimethyl-1,3,5-trimethyl. Examples thereof include cyclotrisiloxanes such as vinylcyclotrisiloxane, cyclotetrasiloxanes such as octamethylcyclotetrasiloxane, and cyclopentasiloxanes such as decamethylcyclopentasiloxane. Of these, cyclotrisiloxane is particularly preferred.

[Fluorosilane compound represented by general formula (2)]
R ^{3 to} R ⁵ in the fluorosilane compound represented by the general formula (2) are organic groups having 1 to 12 carbon atoms which may be the same or different from each other. Examples of R ^{3 to} R ⁵ include a chain alkyl group, a cyclic alkyl group, an alkenyl group, an alkynyl group, a halogenated alkyl group, and a saturated heterocyclic group mentioned as examples of R ¹ and R ² in the general formula (1). In addition to aryl groups such as phenyl groups which may have alkyl groups, aralkyl groups, trialkylsilyl groups, trialkylsiloxy groups, carbonyl groups such as ethoxycarbonylethyl groups; acetoxy groups, acetoxymethyls Group, carboxyl group such as trifluoroacetoxy group; oxy group such as methoxy group, ethoxy group, propoxy group, butoxy group, phenoxy group, allyloxy group; amino group such as allylamino group; benzyl group and the like.

  In general formula (2), x represents an integer of 1 to 3, p, q, and r each represents an integer of 0 to 3, and 1 ≦ p + q + r ≦ 3. Inevitably, x + p + q + r = 4.

  Examples of the fluorosilane compound represented by the general formula (2) include trimethylfluorosilane, triethylfluorosilane, tripropylfluorosilane, phenyldimethylfluorosilane, triphenylfluorosilane, vinyldimethylfluorosilane, vinyldiethylfluorosilane, In addition to monofluorosilanes such as vinyldiphenylfluorosilane, trimethoxyfluorosilane, and triethoxyfluorosilane, difluorosilanes such as dimethyldifluorosilane, diethyldifluorosilane, divinyldifluorosilane, and ethylvinyldifluorosilane; methyltrifluorosilane, Also included are trifluorosilanes such as ethyltrifluorosilane.

  If the boiling point of the fluorosilane compound represented by the general formula (2) is low, it will volatilize, and therefore it may be difficult to contain a predetermined amount in the non-aqueous electrolyte. Moreover, even if it is made to contain in a non-aqueous electrolyte solution, there exists a possibility that it may volatilize on the conditions that the heat_generation | fever of a battery by charging / discharging or an external environment becomes high temperature. Accordingly, those having a boiling point of 50 ° C. or higher at 1 atm are preferable, and those having a boiling point of 60 ° C. or higher are particularly preferable.

  In addition, as with the compound of the general formula (1), the organic group having a smaller number of carbon atoms is more effective, and the alkenyl group having 1 to 6 carbon atoms can be applied to a non-aqueous electrolyte solution or a coating on the electrode surface. It acts to improve the input / output characteristics, and the aryl group has the effect of capturing the radicals generated in the battery during charge / discharge and improving the overall battery performance. Therefore, from this viewpoint, the organic group is preferably a methyl group, a vinyl group, or a phenyl group, and examples of the compound include trimethylfluorosilane, vinyldimethylfluorosilane, phenyldimethylfluorosilane, and vinyldiphenylfluorosilane. .

[Compound represented by formula (3)]
R < ⁶ > -R < ⁸ > in the compound represented by General formula (3) is a C1-C12 organic group which may mutually be same or different. Examples of R ^{6 to} R ⁸ include chain alkyl groups, cyclic alkyl groups, alkenyl groups, alkynyl groups, halogenated alkyl groups, and saturated heterocyclic groups mentioned as examples of R ^{3 to} R ^{5 in} the general formula (2). An aryl group such as a phenyl group which may have an alkyl group, an aralkyl group, a trialkylsilyl group, a trialkylsiloxy group, a carbonyl group, a carboxyl group, an oxy group, an amino group, a benzyl group, etc. The same can be said.

A in the compound represented by the general formula (3) is not particularly limited as long as A is a group composed of H, C, N, O, F, S, Si and / or P. However, C, S, Si, or P is preferable as the element directly bonded to the oxygen atom in the general formula (3). Examples of the existence form of these atoms include a chain alkyl group, a cyclic alkyl group, an alkenyl group, an alkynyl group, a halogenated alkyl group, a carbonyl group, a sulfonyl group, a trialkylsilyl group, a phosphoryl group, and a phosphinyl group. Those are preferred.
The molecular weight of the compound represented by the general formula (3) is preferably 1000 or less, particularly preferably 800 or less, and more preferably 500 or less.

  Examples of the compound represented by the general formula (3) include siloxane compounds such as hexamethyldisiloxane, 1,3-diethyltetramethyldisiloxane, hexaethyldisiloxane, and octamethyltrisiloxane; methoxytrimethylsilane, ethoxy Alkoxysilanes such as trimethylsilane; peroxides such as bis (trimethylsilyl) peroxide; carboxylic acid esters such as trimethylsilyl acetate, triethylsilyl acetate, trimethylsilyl propionate, trimethylsilyl methacrylate, and trimethylsilyl trifluoroacetate; methanesulfonic acid Sulfonic acid esters such as trimethylsilyl, trimethylsilyl ethanesulfonate, triethylsilyl methanesulfonate, trimethylsilyl fluoromethanesulfonate; bis (trimethylsilyl) Sulfuric esters such as sulfates; tris (trimethylsiloxy) borate esters such as boron; tris (trimethylsilyl) phosphate, tris (trimethylsilyl) phosphite phosphoric acid or phosphorous acid esters such as phosphite and the like.

  Of these, siloxane compounds, sulfonic acid esters, and sulfuric acid esters are preferable, and sulfonic acid esters are particularly preferable. The siloxane compound is preferably hexamethyldisiloxane, the sulfonic acid ester is preferably trimethylsilyl methanesulfonate, and the sulfuric acid ester is preferably bis (trimethylsilyl) sulfate.

[Compound with SF bond in molecule]
The compound having an S—F bond in the molecule is not particularly limited, but sulfonyl fluorides and fluorosulfonic acid esters are preferable. For example, methanesulfonyl fluoride, ethanesulfonyl fluoride, methanebis (sulfonylfluoride), ethane-1,2-bis (sulfonylfluoride), propane-1,3-bis (sulfonylfluoride), butane-1,4 -Bis (sulfonyl fluoride), difluoromethane bis (sulfonyl fluoride), 1,1,2,2-tetrafluoroethane-1,2-bis (sulfonyl fluoride), 1,1,2,2,3 Examples include 3-hexafluoropropane-1,3-bis (sulfonyl fluoride), methyl fluorosulfonate, ethyl fluorosulfonate, and the like. Of these, methanesulfonyl fluoride, methanebis (sulfonyl fluoride) or methyl fluorosulfonate is preferable.

[Nitrate, nitrite, monofluorophosphate, difluorophosphate, acetate, propionate]
The counter cation of nitrate, nitrite, monofluorophosphate, difluorophosphate, acetate, propionate is not particularly limited, but metal elements such as Li, Na, K, Mg, Ca, Fe, Cu, etc. In addition, ammonium and quaternary ammonium represented by NR ⁹ R ¹⁰ R ¹¹ R ¹² (wherein R ^{9 to} R ¹² each independently represents a hydrogen atom or an organic group having 1 to 12 carbon atoms). Is mentioned. Here, the organic group having 1 to 12 carbon atoms of R ^{9 to} R ¹² is an alkyl group which may be substituted with a halogen atom, a cycloalkyl group which may be substituted with a halogen atom, or a halogen atom. An aryl group which may be present, a nitrogen atom-containing heterocyclic group, and the like. Especially, as R < ⁹ > -R < ¹² >, a hydrogen atom, an alkyl group, a cycloalkyl group, a nitrogen atom containing heterocyclic group, etc. are respectively preferable.

Among these counter cations, lithium, sodium, potassium, magnesium, calcium or NR ⁹ R ¹⁰ R ¹¹ R ¹² is preferable, and lithium is particularly preferable from the viewpoint of battery characteristics when used in a non-aqueous electrolyte secondary battery. Of these, nitrate or difluorophosphate is preferable in terms of the effect of improving output, battery cycle and high-temperature storage characteristics, and lithium difluorophosphate is particularly preferable. In addition, these compounds may be used substantially as they are synthesized in a non-aqueous solvent, or contained in a non-aqueous solvent or a non-aqueous electrolyte solution that are separately synthesized and substantially isolated. You may let them.

  A specific compound, that is, a cyclic siloxane compound represented by the general formula (1), a fluorosilane compound represented by the general formula (2), a compound represented by the general formula (3), and an SF bond in the molecule. Compound, nitrate, nitrite, monofluorophosphate, difluorophosphate, acetate or propionate may be used alone, or two or more compounds may be used in any combination and ratio May be. Moreover, even if it is a compound classified into said each with a specific compound, 1 type may be used independently and 2 or more types of compounds may be used together by arbitrary combinations and ratios.

  The ratio of these specific compounds in the non-aqueous electrolyte is generally 10 ppm or more (0.001 mass% or more) in total with respect to the total non-aqueous electrolyte, preferably 0.01 mass% or more, more preferably Is 0.05 mass% or more, more preferably 0.1 mass% or more. The upper limit is preferably 5% by mass or less, more preferably 4% by mass or less, and still more preferably 3% by mass or less. If the concentration of the specific compound is too low, the effect of maintaining the output characteristics and the effect of suppressing gas generation may be difficult to obtain even after long-term use, while if the concentration is too high, the charge / discharge efficiency may be reduced. May invite.

[III-2-2-3-4. Other compounds]
The non-aqueous electrolyte solution in the non-aqueous electrolyte secondary battery of the present invention can further contain other compounds as required in an arbitrary amount as long as the effects of the present invention are not impaired. As such other compounds, specifically, for example,
(1) Aromatic compounds such as biphenyl, alkylbiphenyl, terphenyl, partially hydrogenated terphenyl, cyclohexylbenzene, t-butylbenzene, t-amylbenzene, diphenyl ether, dibenzofuran; 2-fluorobiphenyl, o-cyclohexylfluoro Partially fluorinated products of the above-mentioned aromatic compounds such as benzene and p-cyclohexylfluorobenzene; fluorinated anisole such as 2,4-difluoroanisole, 2,5-difluoroanisole, 2,6-difluoroanisole, and 3,5-difluoroanisole Overcharge inhibitors such as compounds;
(2) vinylene carbonate, vinyl ethylene carbonate, fluoroethylene carbonate, trifluoropropylene carbonate, succinic anhydride, glutaric anhydride, maleic anhydride, citraconic anhydride, glutaconic anhydride, itaconic anhydride, cyclohexanedicarboxylic anhydride, etc. Negative electrode film-forming agent;
(3) Ethylene sulfite, propylene sulfite, dimethyl sulfite, propane sultone, butane sultone, methyl methanesulfonate, busulfan, methyl toluenesulfonate, dimethyl sulfate, ethylene sulfate, sulfolane, dimethyl sulfone, diethyl sulfone, dimethyl sulfoxide, diethyl sulfoxide Positive electrode protective agents such as tetramethylene sulfoxide, diphenyl sulfide, thioanisole, diphenyl disulfide, dipyridinium disulfide;
Etc.

  Among these, as the overcharge inhibitor, aromatic compounds such as biphenyl, alkylbiphenyl, terphenyl, partially hydrogenated terphenyl, cyclohexylbenzene, t-butylbenzene, t-amylbenzene, diphenyl ether, and dibenzofuran are preferable. These may be used alone or in combination of two or more in any combination and ratio. However, when using 2 or more types together, it is particularly preferable to use cyclohexylbenzene or terphenyl (or a partially hydrogenated product thereof) together with t-butylbenzene or t-amylbenzene.

Further, as the negative electrode film forming agent, carbonate, vinyl ethylene carbonate, fluoroethylene carbonate, succinic anhydride, and maleic anhydride are preferable. These may be used alone or in combination of two or more in any combination and ratio.
Furthermore, as the positive electrode protective agent, ethylene sulfite, propylene sulfite, propane sultone, butane sultone, methyl methanesulfonate, and busulfan are preferable. These may be used alone or in combination of two or more in any combination and ratio. Moreover, the combined use of a negative electrode film forming agent and a positive electrode protective agent, or the combined use of an overcharge inhibitor, a negative electrode film forming agent, and a positive electrode protective agent is particularly preferable.

  The content ratio of these other compounds in the non-aqueous electrolyte solution is not particularly limited, but is usually 0.01% by mass or more, preferably 0.1% by mass or more, more preferably, based on the whole non-aqueous electrolyte solution. The upper limit is usually 5% by mass or less, preferably 3% by mass or less, and more preferably 2% by mass or less. By using these compounds, it is possible to suppress the gas generation, rupture and ignition of the battery at the time of abnormality due to overcharge or the like, and to improve the capacity maintenance characteristic and cycle characteristic after high temperature storage.

[III-2-2-4. Separator]
The separator has a predetermined mechanical strength that electrically insulates both electrodes, has a high ion permeability, and has both resistance to oxidation on the side in contact with the positive electrode and reduction on the negative electrode side. It is not particularly limited. As a material for the separator having such required characteristics, for example, a resin, an inorganic material, glass fiber, or the like is used. As the resin, olefin polymer, fluorine polymer, cellulose polymer, polyimide, nylon and the like are used. Specifically, it is preferable to select from materials that are stable with respect to the non-aqueous electrolyte and have excellent liquid retention properties, and it is preferable to use a porous sheet or nonwoven fabric made of polyolefin such as polyethylene and polypropylene. preferable.

As the inorganic substance, oxides such as alumina and silicon dioxide, nitrides such as aluminum nitride and silicon nitride, and sulfates such as barium sulfate and calcium sulfate are used, and those having a particle shape or fiber shape are used. As the form, a thin film shape such as a non-woven fabric, a woven fabric, or a microporous film is used. In the thin film shape, those having a pore diameter of 0.01 to 1 μm and a thickness of 5 to 50 μm are preferably used.
In addition to the independent thin film shape, a separator formed by forming a composite porous layer containing the inorganic particles on the surface layer of the positive electrode and / or the negative electrode using a resin binder can be used. For example, a porous layer may be formed by using alumina particles having a 90% particle size of less than 1 μm on both surfaces of the positive electrode and using a fluororesin as a binder.

In addition, you may comprise a separator integrally as an electrode group with the above-mentioned positive electrode and negative electrode. As a specific configuration of the electrode group, for example, the above-described positive electrode plate and negative electrode plate having a laminated structure including the above-described separator, and the above-described positive electrode plate and negative electrode plate having a spiral shape via the above-described separator are used. Any of the structures wound in the above manner may be used.
The ratio of the electrode group volume to the battery internal volume (hereinafter referred to as electrode group occupancy ratio) is usually 40% or more, preferably 50% or more, and usually 90% or less, preferably 80% or less. If the electrode group occupancy is less than 40%, the battery capacity is small, and if it is 90% or more, the void space is small, the member expands when the battery becomes high temperature, and the vapor pressure of the liquid component of the electrolyte is high. As a result, the internal pressure rises, and various characteristics such as charge / discharge repetition performance and high-temperature storage as a battery are deteriorated. Further, a gas release valve that releases the internal pressure to the outside may operate.

[III-2-2-5. Current collector terminal]
The non-aqueous electrolyte secondary battery of the present invention preferably includes a current collecting terminal as appropriate. The current collecting terminal is a terminal used to construct a current collecting structure that reduces the resistance of the wiring part and the joint part, and in order to more effectively realize the improvement of the low-temperature discharge characteristics by the non-aqueous electrolyte described above. It is suitable for use. In the case where the internal resistance of the wiring portion and the joint portion is reduced by forming such a current collecting structure, the effect of using the non-aqueous electrolyte solution is exhibited particularly well.

  For example, when the electrode group has the above-described laminated structure, a current collecting structure of a type formed by bundling the metal core portions of the electrode layers and welding them to the current collecting terminals is preferably used. Further, for example, when the area of one electrode is increased, the internal resistance is increased. Therefore, it is also preferable to reduce the resistance by providing a plurality of current collecting terminals in the electrode. Further, for example, in the case where the electrode group has the winding structure described above, the internal resistance can be lowered by providing a plurality of lead structures on the positive electrode and the negative electrode, respectively, and bundling the current collector terminals.

  By optimizing the current collecting structure described above, the internal resistance can be made as small as possible. Specifically, for example, in a battery used with a large current, it is preferable to set an impedance (hereinafter abbreviated as “DC resistance component”) measured by a 10 kHz AC method to 10 milliohms (mΩ) or less. Is more preferably 5 milliohms (mΩ) or less. When the direct current resistance component is 0.1 milliohm or less, the high output characteristics are improved, but the ratio of the current collecting structure material (current collecting terminal, etc.) used increases, and the battery capacity may decrease.

  The non-aqueous electrolyte described above is effective in reducing reaction resistance related to lithium insertion / extraction with respect to the electrode active material, which is a factor that can realize good low-temperature discharge characteristics. However, in a battery having a normal DC resistance greater than 10 milliohms (mΩ), the effect of reducing reaction resistance may not be reflected 100% on the low-temperature discharge characteristics due to inhibition by the DC resistance. This can be improved by using a battery having a small DC resistance component, and the effect of the non-aqueous electrolyte solution of the present invention can be sufficiently exhibited.

  Further, from the viewpoint of drawing out the effect of the non-aqueous electrolyte and producing a battery having high low-temperature discharge characteristics, this requirement and the electric capacity of the battery element housed in one battery exterior of the secondary battery described above. It is particularly preferable to satisfy the requirement that (the electric capacity when the battery is discharged from the fully charged state to the discharged state) is 3 Ah or more at the same time.

[III-2-2-6. Exterior case]
The material of the outer case is not particularly limited as long as it is a substance that is stable with respect to the nonaqueous electrolyte used. As specific examples, nickel-plated steel plates, stainless steel, aluminum, aluminum alloys, magnesium alloys and other metals, or laminated films (laminate films) of resin and aluminum foil are used. From the viewpoint of weight reduction, an aluminum or aluminum alloy metal or a laminate film is preferably used.

In the exterior case using the above metals, a laser-sealed, resistance-welded, ultrasonic welding is used to weld the metals together to form a sealed sealed structure, or a caulking structure using the above-mentioned metals via a resin gasket To do.
Examples of the outer case using the laminate film include those having a sealed and sealed structure by heat-sealing resin layers. In order to improve the sealing performance, a resin different from the resin used for the laminate film may be interposed between the resin layers. In particular, when a resin layer is heat-sealed through a current collecting terminal to form a sealed structure, a metal and a resin are joined, so that a resin having a polar group or a modified group having a polar group introduced as an intervening resin is used. Resins are preferably used.

[III-2-2-7. Protective element]
As the above protection elements, PTC (Positive Temperature Coefficient), thermal fuse, thermistor, whose resistance increases when abnormal heat generation or excessive current flows, current flowing through the circuit due to sudden rise in battery internal pressure or internal temperature at abnormal heat generation Examples include a valve (current cutoff valve) that shuts off. It is preferable to select a protective element that does not operate under normal use at a high current. From the viewpoint of high output, it is more preferable to design the protective element so as not to cause abnormal heat generation or thermal runaway even without the protective element.

[III-2-3. Preparation of non-aqueous electrolyte secondary battery]
The method for producing the non-aqueous electrolyte secondary battery of the present invention is not particularly limited, and can be performed by any method. For example, it can be manufactured by the following method. That is, the positive electrode and the negative electrode are alternately arranged, and are laminated or wound so that the separator is sandwiched between the electrodes. At this time, the positive electrode active material surface is faced so as not to deviate from the negative electrode active material surface. The uncoated portions of each of the positive electrode and the negative electrode are bundled together and connected together with, for example, spot welding or the like with a metal piece serving as a current collecting terminal to produce a current collecting tab, thereby forming an electrode group.

  As a battery exterior material, for example, a sheet in which a polypropylene film, an aluminum foil, a nylon film, and the like are laminated in this order is used, and an exterior case is formed so that the polypropylene film comes on the inner surface side. The aforementioned electrode group is sealed in an outer case so that the current collecting terminal comes out from the unsealed portion at the end of the cup, and a non-aqueous electrolyte is injected to sufficiently penetrate the electrode. This can be sealed by heat-sealing the upper end of the cup under reduced pressure to produce a non-aqueous electrolyte secondary battery.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited to these Examples, unless it deviates from the summary.

[Example 1: Evaluation of battery by overcharge test]
Oversized test for various batteries as a booth for safety test using a box-shaped stainless steel pressure-resistant sealed container with outer dimensions of width 1000mm, depth 800mm, height 1000mm, inner volume 450 liter, pressure resistance 0.2MPa I did it.
This booth includes a supply pipe that can replace the inside of the booth with air, a nitrogen supply pipe that can replace the inside of the booth with nitrogen, and a vacuum pipe that can decompress the inside of the booth. Each pipe is equipped with a valve very close to the booth, so that the pressure resistance and airtightness of the booth body can be maintained.

The booth is equipped with a blast pressure sensor, and the pressure inside the booth can be measured.
In addition, a charging / discharging cable connected to an external charger / discharger can be introduced into the booth to charge / discharge the batteries in the booth.
Furthermore, a K-type thermocouple for measuring the temperature inside the booth is introduced from the outside of the booth inside the booth, and the temperature inside the booth can be measured.

The voltage of the battery to be measured was set to 3 V, which is the lower limit voltage in normal use of the battery, by discharging or charging the battery. Subsequently, after charging / discharging cables were connected to the positive electrode terminal and the negative electrode terminal, the battery was installed in a booth.
After sealing the booth, the inside of the booth was replaced with nitrogen, and it was confirmed that the internal pressure of the booth after the replacement was 0.1 MPa (1 atm). Then, it confirmed that the temperature in a booth was 25 degreeC.

Thereafter, the battery was charged at a current of 18 amps until the charge capacity reached 15 amp hours. After the charging operation was completed, the pressure inside the booth was measured when the temperature inside the booth reached 25 ° C.
From the change in the booth pressure before and after the test, the C value could be calculated by the following formula.
C = Booth pressure change before and after the test [Pa] × Booth internal volume [m ³ ] / (Booth internal pressure [Pa] before test × Battery volume [m ³ ])

[Example 2: Evaluation of battery by nail penetration test]
A box-shaped stainless steel pressure-resistant sealed container with outer dimensions of width 1300mm, depth 1000mm, height 1800mm, internal volume 1130 liters, pressure resistance 0.2MPa is used as a booth for conducting safety tests, and a nail test for various batteries Went.
The booth includes a supply pipe that can replace the inside of the booth with air, a nitrogen supply pipe that can replace the inside of the booth with nitrogen, and a vacuum pipe that can decompress the inside of the booth. Each pipe is equipped with a valve in the immediate vicinity of the booth, so that the pressure resistance and airtightness of the booth body can be maintained.

The booth is equipped with a blast pressure sensor, and the pressure inside the booth can be measured.
A hydraulic press is installed inside the booth, and this press can be operated from outside the booth.
Further, a K-type thermocouple for measuring the temperature inside the booth is introduced from the outside of the booth inside the booth, and the temperature inside the booth can be measured.

  The voltage of the battery to be measured was set to 4.1 V, which is the upper limit voltage during normal use of the battery, by discharging or charging the battery. A stainless steel nail having an outer diameter of 2.5 mm was attached to the tip of the movable part of the hydraulic press. Subsequently, when the hydraulic press was moved, the battery was installed in the booth at a position where the nail penetrated perpendicularly to this surface at the intersection of the diagonal lines of the 120 × 110 mm surface of the battery. After sealing the booth, the inside of the booth was replaced with nitrogen, and it was confirmed that the internal pressure of the booth after the replacement was 0.1 MPa (1 atm). Then, it confirmed that the temperature in a booth was 25 degreeC.

Thereafter, the movable part of the hydraulic press was moved to penetrate the battery into the battery. After 6 hours, it was confirmed that the temperature in the booth was 25 ° C., and the pressure in the booth was measured.
From the change in the booth pressure before and after the test, the C value could be calculated by the following formula.
C = Booth pressure change before and after the test [Pa] × Booth internal volume [m ³ ] / (Booth internal pressure [Pa] before test × Battery volume [m ³ ])

[Example 3: Evaluation of battery by heating test]
A box-shaped stainless steel pressure-resistant sealed container with a width of 1000 mm, a depth of 800 mm, a height of 1000 mm, an internal volume of 450 liters, and a pressure resistance of 0.2 MPa is used as a booth for conducting safety tests, and heat tests are performed on various batteries. It was.
This booth includes a supply pipe that can replace the inside of the booth with air, a nitrogen supply pipe that can replace the inside of the booth with nitrogen, and a vacuum pipe that can decompress the inside of the booth. Each pipe is equipped with a valve in the immediate vicinity of the booth, so that the pressure resistance and airtightness of the booth body can be maintained.

Inside the booth, a K-type thermocouple for measuring the temperature inside the booth and the battery surface temperature is introduced from outside the booth, and the temperature inside the booth and the battery surface temperature can be measured.
In addition, a box oven for heating the battery is installed inside the booth.

The voltage of the battery to be measured was set to 4.1 V, which is the upper limit voltage during normal use of the battery, by discharging or charging it. Subsequently, a K-type thermocouple was installed at the intersection of the diagonal lines of the 120 × 110 mm surface of the battery so that the battery surface temperature could be measured. The battery was placed in a battery heating oven installed in the booth. After the booth was sealed, the inside of the booth was replaced with nitrogen. Then, it confirmed that the temperature in a booth was 25 degreeC.
Thereafter, the ambient temperature of the battery in the oven was increased at 1 K / min until it reached 150 ° C. After reaching 150 ° C., it was left in that state for 10 minutes, and the oven was allowed to cool to room temperature. Through this test, the transition of the battery surface temperature could be measured.

[Example 4: Production and evaluation of battery]
[Production of positive electrode]
90% by weight of lithium nickelate (LiNiO ₂ ) as a positive electrode active material, 5% by weight of acetylene black as a conductive material, and 5% by weight of polyvinylidene fluoride (PVdF) as a binder, an N-methylpyrrolidone solvent Mixed in to a slurry. The obtained slurry was applied to both sides of a 15 μm aluminum foil, dried, rolled to a thickness of 80 μm with a press, and the active material layer had an uncoated part with a width of 100 mm, a length of 100 mm and a width of 30 mm. It cut out into the shape and it was set as the positive electrode.

[Production of negative electrode]
Artificial graphite powder KS-44 (manufactured by Timcal, trade name) 98 parts by weight, 100 parts by weight of an aqueous dispersion of carboxymethylcellulose sodium (concentration of 1% by weight of carboxymethylcellulose sodium) as a thickener and binder, 2 parts by weight of an aqueous dispersion of styrene-butadiene rubber (concentration of styrene-butadiene rubber 50% by weight) was added and mixed with a disperser to form a slurry. The obtained slurry was applied to both sides of a 10 μm copper foil, dried, rolled to 75 μm with a press, and formed into a shape having an uncoated part with a width of 104 mm, a length of 104 mm, and a width of 30 mm as the size of the active material layer. It cut out and it was set as the negative electrode.

[Preparation of electrolyte]
Under a dry argon atmosphere, a well-dried hexafluorophosphorus at a concentration of 1 mol / L in a mixture of ethylene carbonate (EC), dimethyl carbonate (DMC) and ethyl methyl carbonate (EMC) (volume ratio 3: 3: 4) Lithium acid (LiPF ₆ ) was dissolved. Furthermore, lithium difluorophosphate (LiPO ₂ F ₂ ) was contained so as to be 0.3% by mass.

[Production of battery]
32 positive electrodes and 33 negative electrodes were alternately arranged and laminated such that a separator (25 μm) of a porous polyethylene sheet was sandwiched between the electrodes. At this time, the positive electrode active material surface was faced so as not to deviate from the negative electrode active material surface. The uncoated portions of each of the positive electrode and the negative electrode were welded together to produce a current collecting tab, and an electrode group was enclosed in a battery can (outside dimension: 120 × 110 × 10 mm). Thereafter, 20 mL of a non-aqueous electrolyte solution was injected into a battery can loaded with the electrode group, sufficiently infiltrated into the electrode, and sealed to produce a prismatic battery.
The rated discharge capacity of this battery is about 6 ampere hours (Ah), and the DC resistance component measured by the 10 kHz AC method is about 5 milliohms (mΩ). The ratio of the total electrode area of the positive electrode to the sum of the outer surface areas of the batteries is 20.6.

[Battery evaluation]
A new battery that had not undergone the actual charge / discharge cycle was subjected to initial charge / discharge for 5 cycles at 25 ° C. The 5th cycle 0.2I _C at this time (the rated capacity due to the discharge capacity at 1 hour rate is set to 1 I _{C as} the current value for discharging in 1 hour, and so on), and the discharge capacity was the initial capacity.
Under 25 ° C. environment, performs charging for 150 minutes by a constant current of 0.2i _C, respectively _{0.1I C, 0.3I C, 1.0I C} , 3.0I C, was discharged for 10 seconds at 10.0I _C The voltage at the 10th second was measured. The area of the triangle surrounded by the current-voltage line and the lower limit voltage (3 V) was defined as output (W). This battery had an initial capacity of 6005 mAh and an output of 502 W.

[Example 5: Evaluation of battery by overcharge test]
The new battery that was not subjected to the charge / discharge cycle prepared in Example 4 was subjected to initial charge / discharge for 5 cycles at 25 ° C., and then used as a battery for safety testing. This battery is subjected to an overcharge test under the same conditions as described above for the overcharge test. The C value calculated from the change in the booth pressure before and after the test is 10 or less.

[Example 6: Evaluation of battery by nail penetration test]
The new battery that was not subjected to the charge / discharge cycle prepared in Example 4 was subjected to initial charge / discharge for 5 cycles at 25 ° C., and then used as a battery for safety testing. A nail penetration test is performed on this battery under the same conditions as described above for the nail penetration test. The C value calculated from the change in the booth pressure before and after the test is 10 or less.

[Example 7: Evaluation of battery by heating test]
The new battery that was not subjected to the charge / discharge cycle prepared in Example 4 was subjected to initial charge / discharge for 5 cycles at 25 ° C., and then used as a battery for safety testing. The battery is subjected to a heating test under the same conditions as those described above for the heating test, and the maximum value of the battery surface temperature through the heating test is measured. Throughout this test, the maximum battery surface temperature does not exceed 155 ° C.

  The present invention is suitable for use in a safety test of a power storage and supply device, and is suitable for use in, for example, research and development of a battery or a capacitor. Moreover, the non-aqueous electrolyte secondary battery developed using the test apparatus of the present invention can be used for various known applications. Specific examples include notebook computers, pen input computers, mobile computers, electronic book players, mobile phones, mobile faxes, mobile copy, mobile printers, headphone stereos, video movies, LCD TVs, handy cleaners, portable CDs, minidiscs, and transceivers. Widely used in electronic notebooks, calculators, memory cards, portable tape recorders, radios, backup power supplies, motors, automobiles, motorbikes, motorbikes, bicycles, lighting equipment, toys, game equipment, watches, power tools, strobes, cameras, etc. It is what is done.

Although the present invention has been described in detail using specific embodiments, it will be apparent to those skilled in the art that various modifications can be made without departing from the spirit and scope of the invention.
This application is based on a Japanese patent application (Japanese Patent Application No. 2005-037723) filed on Feb. 15, 2005, which is incorporated by reference in its entirety.

Claims (10)

A booth having pressure resistance for conducting a safety test of a power storage and supply device;
An exhaust gas treatment unit capable of treating the exhaust gas generated from the power storage and supply device;
A test apparatus comprising: an exhaust gas sending unit that sends the exhaust gas from the booth to the exhaust gas processing unit according to the processing capacity of the exhaust gas processing unit. An inert gas replacement unit capable of replacing the inside of the booth with an inert gas;
The test apparatus according to claim 1, wherein the booth has a pressure resistance equal to or higher than a booth breakdown voltage A described below.
Booth pressure resistance A: The dose rate is the value obtained by multiplying the TNT dose corresponding to the total calorific value during heating of the power storage and supply device by the TNT yield, and the safety factor to the blast pressure determined by Hopkinson's third root rule. Applied pressure. With an air replacement part that can replace the inside of the booth with air,
The test apparatus according to claim 1, wherein the booth has a pressure resistance equal to or higher than the following booth breakdown voltage B.
Booth pressure resistance B = Initial pressure × (Tb / T0) × Safety factor (However, the initial pressure represents the booth internal pressure before exhaust gas generation during the safety test, Tb represents the combustion flame temperature during the safety test, and T0 is (Represents the ambient temperature in the booth before the generation of exhaust gas during the safety test.) The test apparatus according to any one of claims 1 to 3, further comprising a decompression unit capable of decompressing the inside of the booth to 8 kPa or less. The test apparatus according to claim 1, further comprising a cooling unit that lowers the temperature in the booth. The test apparatus according to claim 1, further comprising an exhaust gas collection unit that collects the exhaust gas. The test apparatus according to claim 6, further comprising an exhaust gas analyzer that analyzes the exhaust gas collected by the exhaust gas collector. The test apparatus according to any one of claims 1 to 7, further comprising a blast pressure sensor that measures a blast pressure of the explosion when an explosion of the power storage and supply device occurs. A safety test of the power supply device is performed using the test apparatus according to any one of claims 1 to 8, and the safety evaluation of the power supply device is performed based on the test result. , Safety evaluation method for power supply devices. 10. The safety test according to claim 9, wherein the safety test is selected from a nail penetration test, an overcharge test, a heating test, an external short circuit test, a drop test, a crush test, an overdischarge test, a thermal shock test, and a vibration test. The safety evaluation method for the power supply device described .

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