JP2017174704A - Safety evaluation test method for power storage device, and safety evaluation test apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quantitatively confirm safety of a power storage device by utilizing a dummy power storage device configured by combining an electrode substance and a separator, without using an electrolyte.SOLUTION: A safety evaluation test method executes the steps of: forming a dummy power storage device S0 by interposing and overlapping a sheet-like separator substance S2 on a stage 1 between a sheet-like positive electrode substance S3 including a cathode collector and a cathode active material layer and a sheet-like negative electrode substance S1 including an anode collector and an anode active material layer; supplying a determined voltage or current between the cathode collector and the anode collector of the dummy power storage device; and short-circuiting the cathode collector and the anode collector by moving a test nail 2 towards the stage and penetrating the dummy power storage device S0 with the test nail. By short-circuiting the cathode collector and the anode collector, it is verified whether the electrode substances of the dummy power storage device are shifted into a combustion state.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a safety evaluation test method and a safety evaluation test apparatus for conducting a safety evaluation test on an electricity storage device represented by a lithium ion battery.

  Lithium ion batteries, which occupy an important corner of power storage devices in recent years, have a high energy density compared to other secondary batteries, and a high output voltage can be obtained in a single cell. Demand for power storage devices for power storage is expanding, and the market size is expanding in the field of portable terminal devices such as notebook computers and smartphones.

  However, when an internal short circuit occurs in a lithium ion battery, a sudden heat generation (Joule heat, etc.) occurs, and the organic electrolyte inside the battery decomposes and evaporates, generating harmful gas, explosion and blowing out flames. There is a high possibility that it will develop into an accident, and there are still safety issues. In order to solve this problem, in order to confirm the safety of the battery, the safety evaluation test is emphasized, and some tests that are likely to cause an internal short circuit of the battery are employed.

As a representative example, a means for verifying safety is used in a state in which a conductive foreign object is inserted into a completed test object (lithium ion battery) to simulate an internal short circuit.
As an example, there is a so-called “nail penetration test” (Non-patent Document 1), which is a test in which an iron nail is driven into a battery to cause an internal short circuit.
This can cause fever, smoke, fire and rupture during testing. In other words, the current “nail penetration test” is a safety measure for confirming that heat generation, smoke generation, ignition or rupture that would lead to an accident does not occur when a short circuit occurs inside the battery for various reasons. It is positioned as an evaluation test.

  Therefore, from the viewpoint of preventing human and physical damage during this test, the test is performed in a high pressure-resistant and explosion-proof chamber capable of withstanding a large internal pressure, or the inside of the sealed chamber is inert with, for example, argon gas. There are also proposals (Non-Patent Document 2, Patent Document 1) for satisfying and suppressing the ignition and performing a test.

"Consideration of nail penetration test method for commercial lithium-ion battery" (Annual Report NTT Facilities Research Institute Report No. 24 June 2013 Author: Takefumi Isobe, Masayasu Arakawa) "Safety evaluation test for in-vehicle lithium-ion batteries" (Koveruniku No.36, OCT.2009 Author: Atsushi Imabe)

JP 2011-3513 A

In the nail penetration test, the completed battery is handled as a test object as described above.
Then, the thermal energy generated when the positive electrode and the negative electrode of the battery are short-circuited by the iron nail leads to combustion of the electrolyte composed of organic matter, which is accompanied by the above-described ignition and rupture. Therefore, in order to prevent damage from the ignition and rupture, it is necessary to introduce a relatively large facility as shown in Patent Document 1 and Non-Patent Document 2 in the nail penetration test.

By the way, when performing the safety evaluation test by the internal short circuit of the battery described above, the electrode material itself is combusted by the electrical energy by short-circuiting the electrode material of the positive electrode and the negative electrode even in the absence of the electrolyte. It has been found that this is not generally known.
Therefore, by using the above-described event, a pseudo electricity storage device using a combination of an electrode material constituting a positive electrode and a negative electrode, a separator, and a DC power source applied to the electrode material can be used without using an electrolyte. Thus, it is possible to quantitatively confirm the safety of this type of power storage device.
In other words, it is possible to evaluate the safety by observing the behavior when an internal short circuit occurs in the power storage device in the material stage before the assembly of the power storage device.

The present invention has been made based on the above-described technical viewpoint, and utilizes a pseudo electricity storage device by a combination of an electrode material and a separator without using an electrolytic solution, and the case where this electrode material and separator are used. It is intended to quantitatively confirm the safety of the electricity storage device.
In addition, the present invention basically uses a small amount of electrode material and a separator constituting a single cell, and by utilizing an external power source for this, a large-capacity electricity storage device in which cells are connected in parallel. An object of the present invention is to provide a safety evaluation test method and a test apparatus for an assumed power storage device.

  A safety evaluation test method for an electricity storage device according to the present invention, which has been made to achieve the above-described problems, includes a sheet-like positive electrode material including a positive electrode current collector and a positive electrode active material layer, a negative electrode current collector, and a negative electrode active material. A step of forming a pseudo electricity storage device by interposing a sheet-like separator material or a sheet-like solid electrolyte on a stage between a sheet-like negative electrode material including a substance layer, and the pseudo electricity storage A step of supplying a predetermined voltage or current between the positive electrode current collector and the negative electrode current collector of the device, and a test nail is advanced toward the stage, and the pseudo power storage device is penetrated by the test nail A step of short-circuiting the positive electrode current collector and the negative electrode current collector, and the short-circuit between the positive electrode current collector and the negative electrode current collector causes the electrode material of the pseudo power storage device to be in a combustion state Characterized in that it verifies whether migration.

In this case, as the positive electrode material and the negative electrode material, there may be used a material obtained by removing the electrolyte solution from a charged battery.
Preferably, a pipe-like stage or a planar stage is used as the stage on which the pseudo power storage device is placed.
Then, it is desirable to perform the verification by changing a voltage value or a current value supplied between the positive electrode current collector and the negative electrode current collector.

  Further, the verification may be performed in a state where the stage is heated or cooled. Further, as the test nail, a plurality of test nails having different diameters or a plurality of test nails having different tip shapes are used. In some cases, the verification is performed, and further, the verification is performed by changing the traveling speed of the test nail toward the stage.

  On the other hand, a safety evaluation test apparatus for an electricity storage device according to the present invention, which has been made to achieve the above-described problem, includes a sheet-like positive electrode material including a positive electrode current collector and a positive electrode active material layer, a negative electrode current collector, A stage on which a pseudo electricity storage device configured by stacking a sheet-like separator material or a sheet-like solid electrolyte interposed between and sandwiching a sheet-like negative electrode material including a negative electrode active material layer; and A power supply device that supplies a voltage or current determined between the positive electrode current collector and the negative electrode current collector of the pseudo electricity storage device, and proceeds toward the stage side, by penetrating the pseudo electricity storage device, A test nail capable of short-circuiting the positive electrode current collector and the negative electrode current collector is provided.

  In this case, it is desirable that a pipe-like stage or a planar stage is configured to be replaceable as a stage on which the pseudo power storage device is placed. The plate to which the pipe-like stage is attached is preferably provided with a chuck mechanism that grips both ends of the positive electrode material, the separator material, and the negative electrode material.

The power supply device is preferably configured such that a voltage value or a current value supplied between the positive electrode current collector and the negative electrode current collector can be changed.
In addition, in a preferred embodiment, a heater or cooling means capable of heating or cooling the stage on which the pseudo power storage device is placed is disposed in the stage.

The test nail is preferably detachably attached to a holder that advances and retracts toward the stage side, and a test nail having a different diameter or a test nail having a different tip shape can be attached to the holder. Is done.
Furthermore, it is preferable that the traveling speed of the test nail toward the stage is configured to be controllable.

  According to the safety evaluation test method and the safety evaluation test apparatus for an electricity storage device according to the present invention described above, a sheet-like separator material is interposed between the sheet-like positive electrode material and the sheet-like negative electrode material. The pseudo electricity storage device formed by superimposing them is placed on a stage and used as a test object. Then, the test nail advances toward the stage while the voltage or current determined between the positive current collector of the positive electrode material and the negative current collector of the negative electrode material is supplied from the power supply device. Thus, an operation of short-circuiting the positive electrode current collector and the negative electrode current collector is performed.

  By verifying whether or not the electrode material of the pseudo power storage device shifts to a continuous combustion state as a result of this short-circuit operation, the safety of this type of power storage device can be quantitatively confirmed. That is, according to the safety evaluation test method and the evaluation test apparatus according to the present invention, it is possible to observe the behavior when an internal short circuit occurs using the pseudo power storage device in the material stage before the assembly of the power storage device. Therefore, safety will be evaluated.

Therefore, according to the safety evaluation test method and the evaluation test apparatus, the short circuit test can be performed without using the electrolyte solution. Therefore, the decomposition of the electrolyte solution, the generation of harmful gas due to evaporation, the explosion and the blowing of flame. It can prevent human and material damage.
Accordingly, it is not always necessary to prepare a high pressure-proof and explosion-proof chamber as disclosed in Patent Document 1 and Non-Patent Document 2 described above, and supplementary equipment such as filling the chamber with an inert gas. . Therefore, compared to the above-described conventional safety evaluation test, it is possible to perform the safety evaluation test of this type of power storage device easily and in a short time.

It is a schematic diagram explaining the safety evaluation test method concerning this invention. It is the front view which showed the safety evaluation test apparatus which concerns on this invention in a partially transparent state. It is the side view which similarly showed the safety evaluation test apparatus in a partially transparent state. It is sectional drawing of the cylindrical stage with which the heater was embed | buried. It is the front view which showed the example of the chuck mechanism which hold | grips the edge part of a sheet-like sample. It is a front view of the plate carrying a planar stage. It is a side view similarly.

As a representative example of the electricity storage device that is the subject of the safety evaluation test method and the safety evaluation test apparatus according to the present invention, the above-described lithium ion battery can be cited.
In this lithium ion battery, a lithium salt of a metal oxide is used as a positive electrode active material. Carbon and a binder as a conductive auxiliary agent are added to the lithium salt, and are coated on both surfaces of, for example, an aluminum foil that functions as a positive electrode current collector. The positive electrode material obtained in this way is formed in a sheet shape.

As the positive electrode sheet, as described above, a sheet in which a mixture containing a positive electrode active material, a conductive material, and a binder is supported on a current collector is used.
Specifically, a material including a material capable of inserting and extracting lithium ions, a carbonaceous material as a conductive material, and a thermoplastic resin as a binder can be used.

Examples of the material capable of inserting and extracting lithium ions include lithium composite oxides containing at least one transition metal such as V, Mn, Fe, Co, and Ni.
In addition, lithium composite oxides having an α-NaFeO ₂ type structure, lithium composite oxides having a spinel type structure such as lithium manganese spinel, lithium iron olivine, and the like can be given. The lithium composite oxide may contain various metal elements, particularly selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Cu, Mg, Al, Ga, In, Zr, Sr and Sn. It is also possible to include at least one metal element.

  In addition, as the negative electrode active material of the lithium ion battery, a carbon-based material capable of inserting and extracting lithium is used. If necessary, a conductive additive and a binder are added to the carbon-based material, and the carbon material is coated on, for example, both surfaces of a copper foil functioning as a negative electrode current collector. The negative electrode material obtained by this is similarly formed into a sheet shape.

As materials capable of occluding and releasing lithium ions in this negative electrode sheet, natural graphite, artificial graphite, cokes, carbon black, pyrolytic carbons, carbon fibers, organic polymer compound fired bodies, etc. Examples thereof include chalcogen compounds such as oxides and sulfides that dope and dedope lithium ions at a low potential.
As the carbonaceous material, a carbon material such as natural graphite, artificial graphite, soft carbon, or hard carbon may be used as a main component, and a lithium salt of a metal oxide such as lithium titanium oxide may be used. Further, a material capable of inserting and extracting lithium ions, lithium metal, a lithium alloy, or the like can be used.

On the other hand, a separator that separates a positive electrode and a negative electrode and prevents a short circuit of current due to contact between both electrodes is used in a lithium ion battery. As this separator, a porous film having a function of allowing lithium ions to pass through is used. As a method for producing the porous film, the separator may be porous as a nonwoven fabric in addition to stretching in a dry or wet manner.
As the material, aramid, glass, cellulose, nylon, vinylon, polyester, polyolefin, rayon, low density polyethylene, ethylene vinyl acetate, synthetic rubber, copolymerized polyamide, copolymerized polyester, etc. are used.

A solid electrolyte may be used for the separator portion.
Solid electrolytes include polyvinylidene fluoride, vinylidene fluoride copolymer, polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, ethylene- Copolymers of tetrafluoroethylene, copolymers of vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene, thermoplastic resins such as thermoplastic polyimide, polyethylene and polypropylene, and polyethylene oxide such as carboxymethyl cellulose, polypropylene oxide, polyvinylidene fluoride, Polyvinylidene fluoride and hexafluoropropylene copolymer, polyacrylamide, polymethyl methacrylate, etc. are used as a polymer matrix to form an electrolyte salt. _{Is, LiPF 6, LiAsF 6, LiBF} 4, LiCF 3 SO 3, LiN (Cl F 2l + 1 SO 2) (C m F 2m + 1 SO 2) (l, m is an integer of 1 or more), or difluoro ( Oxalato) One of lithium borate and the like may be used, or a composite or a gel cross-linked product in which two or more are combined.

  By the way, the sheet-like positive electrode material and the negative electrode material are overlapped with a sheet-like separator material interposed therebetween, thereby forming a pseudo electricity storage device in a state where no organic electrolyte exists. it can. When this pseudo electricity storage device is heated, for example, oxygen is generated from the lithium salt constituting the positive electrode material by heating, and this oxygen acts on the carbon constituting the negative electrode material to ignite and burn.

A safety evaluation test method and an evaluation test apparatus for an electricity storage device according to the present invention cause an internal short circuit in an electricity storage device by a nail penetration test using the pseudo electricity storage device described above in the material stage before the assembly of the electricity storage device. It is. The basic idea is to verify the safety of the electricity storage device by observing the behavior when an internal short circuit occurs, that is, whether or not the electrode material shifts to a continuous combustion state.
This makes it possible to evaluate the safety of the electricity storage device without using an organic electrolyte that is dangerous due to combustion.

FIG. 1 is a schematic diagram for explaining a safety evaluation test method for an electricity storage device according to the present invention, and FIG. 1 also shows a basic configuration of a safety evaluation test apparatus according to the present invention.
The configuration shown in FIG. 1 shows an example in which a pipe-like stage is used as a stage on which a pseudo power storage device is placed. This pipe-like stage 1 is a vertical one that will be described later so that its axis is horizontal. It is attached to the plate surface. The pipe-shaped stage 1 is preferably made of stainless steel, and a heater capable of heating the stage 1 is embedded in the shaft core portion as will be described later.
In this embodiment, a heater for heating the stage 1 is used. However, it is desirable that the heater can be heated and cooled.

A test nail 2 is arranged in a vertical state immediately above the pipe-shaped stage 1, and this test nail 2 is placed on the axis of the pipe-shaped stage 1 as indicated by an arrow by a driving mechanism (actuator) described later. It is configured to be able to move forward (down) or back (up).
In the example shown in FIG. 1, the pipe-shaped stage 1 is overlaid with the sheet-shaped negative electrode material S1, the sheet-shaped separator material S2, and the sheet-shaped positive electrode material S3 in this order. 1, the pseudo power storage device S0 is placed.

A chuck mechanism for gripping each end portion of each electrode material and separator material stacked on the stage 1 is provided, and this chuck mechanism is constituted by a fixed pipe and a movable pipe formed of an insulating material. The
In the example shown in FIG. 1, the first chuck mechanism C <b> 1 that holds each end portion of the negative electrode material S <b> 1 is disposed immediately below the pipe-shaped stage 1. This is composed of one fixed pipe 3 and movable pipes 4L and 4R arranged on the left and right sides of the fixed pipe 3.

  In addition, the movable pipes 4L and 4R whose first chuck mechanism constitutes C1 are configured so that the fixed pipe 3 can be brought into contact with and separated from the fixed pipe 3 as indicated by arrows on both sides thereof. That is, the movable pipes 4L and 4R are positioned away from the fixed pipe 3, the negative electrode material S1 is mounted, and then the movable pipes 4L and 4R are moved to the state shown in FIG. Both ends of the material S1 are gripped by the first chuck mechanism C1 as shown in FIG.

  Further, the second chuck mechanisms C2L and C2R that grip the respective end portions of the separator material S2 are arranged separately on the left and right at an intermediate position between the pipe-like stage 1 and the first chuck mechanism C1. These are composed of fixed pipes 5L and 5R and movable pipes 6L and 6R, and the movable pipes 6L and 6R are configured to be able to contact and separate from the fixed pipes 5L and 5R as indicated by arrows. . Therefore, each end portion of the separator material S2 can also be gripped by the left and right second chuck mechanisms C2L and C2R as shown in FIG.

  Further, third chuck mechanisms C3L and C3R that grip each end of the positive electrode material S3 are arranged separately on the left and right at positions on both outer sides of the pipe-like stage 1. These are constituted by fixed pipes 7L and 7R and movable pipes 8L and 8R. The movable pipes 8L and 8R are configured to be able to contact and separate from the fixed pipes 7L and 7R as indicated by arrows. . Therefore, each end portion of the positive electrode material S3 can also be gripped by the left and right third chuck mechanisms C3L and C3R as shown in FIG.

As shown in FIG. 1, in the state where the electrode materials S1 and S3 and the separator material S2 are set between the electrode materials S1 and S3 on the pipe-shaped stage 1, and the end portions of the materials are gripped by the first to third chuck mechanisms, respectively. The direct current voltage or direct current set in the power supply device is supplied to the positive electrode current collector of the positive electrode material S3 and the negative electrode current collector of the negative electrode material S1.
The DC output from the power supply device is provided from output terminals 9 and 10 disposed slightly below the first chuck mechanism C1.

A lead wire 11 is connected to the output terminal 9 (positive electrode terminal), and, for example, a hook clip 13 attached to the tip of the output terminal 9 is connected to the positive electrode current collector (aluminum foil) that constitutes the positive electrode material S3. The Further, a lead wire 12 is connected to the output terminal 10 (negative electrode terminal), and the same mouth clip 14 attached to the tip of the output terminal 10 is connected to the negative electrode current collector (copper foil) constituting the negative electrode material S1. Connected.
In this state, the above-described test nail 2 descends and penetrates the pseudo power storage device S0 placed on the pipe-shaped stage 1 at its tip.

  Thereby, the positive electrode current collector and the negative electrode current collector are short-circuited via the test nail 2, and a short-circuit current corresponding to the positive electrode material S3, the negative electrode material S1, the DC voltage value from the power supply device, and the like. Flows. It is verified whether or not the pseudo power storage device S0 placed on the pipe-like stage 1 shifts to the combustion state by heat generation (Joule heat generation or the like) at that time.

That is, even if a spark (spark) occurs due to a short circuit between the positive electrode current collector and the negative electrode current collector, if the electrode material does not reach continuous combustion, the combination of each electrode material S1, S3 and separator material S2 is In the range of the set voltage value (MAX voltage) and current value (MAX current), it can be verified that there is no ignition or rupture leading to an accident.
On the other hand, when the electrode material reaches continuous combustion due to heat generation due to a short circuit through the test nail 2, the combination of each electrode material S1, S3 and separator material S2 in this case is a set current value or voltage value. In this range, it can be verified that the degree of occurrence of ignition or rupture that leads to an accident by adding an electrolyte to the electrolyte is large.

  Table 1 shows specific verification results when, for example, three types of separator materials and their thicknesses are used as parameters. In this case, the “MAX voltage” shown in Table 1 particularly verifies the voltage performance of the separator, and the “MAX current” can be adjusted to the capacity of the designed unit cell, and each cell is connected in parallel. This assumes a short-circuit current when a large-capacity storage device connected is assumed.

  As shown in Table 1, Sample No. The combinations shown in Nos. 1, 5 to 9 can be evaluated as not causing ignition or rupture leading to an accident. It can be evaluated that the combinations shown in 2 to 4 are accompanied by dangers such as ignition and rupture that lead to an accident.

  In the safety evaluation test method according to the present invention, safety may be evaluated in a state where the above-described stage 1 on which the pseudo power storage device S0 is placed is heated or cooled. This is because even if the same electrode material S1, S3 and separator material S2 are combined, the safety evaluation may differ depending on the temperature of the battery usage environment.

  Further, in the safety evaluation test method according to the present invention, a stage 1 formed in a pipe shape as shown in FIG. 1 is used. This simulates a state in which an internal short circuit has occurred assuming a battery having an outer shape of a cylindrical shape. For example, in the case of assuming a square (laminated) battery, a plane is used instead of the pipe-shaped stage 1. It is desirable to use a stage. An example of using this planar stage will be described later based on a specific example (FIGS. 6 and 7) of the safety evaluation test apparatus according to the present invention.

Furthermore, in the safety evaluation test method according to the present invention, the diameter of the test nail 2 that makes a pseudo internal short circuit between the positive electrode current collector and the negative electrode current collector, and the progression speed (nail penetration speed) are made different. A means to evaluate safety is also adopted.
The diameter of the test nail assumes the size of the foreign matter that causes an internal short circuit, and the dependence on the size of the foreign matter can be verified by replacing the test nail for evaluation.
The nail penetration speed also depends, and is necessary in that the reproducibility of the evaluation test can be confirmed.

2 to 7 show specific examples of the safety evaluation test apparatus according to the present invention.
2-7, the part which performs the same function as each part demonstrated based on FIG. 1 is shown with the same code | symbol, Therefore The detailed description is abbreviate | omitted suitably.
As shown in FIGS. 2 and 3, the casing 21 constituting the outer shell of the evaluation test apparatus is formed in a substantially rectangular parallelepiped shape as a whole, and is located at a position occupying most of the front upper portion thereof in FIG. 1. The main parts shown are arranged.

That is, a plate 22A is attached to the housing 21 at the center of the front surface, and the pipe-like stage 1, the first chuck mechanism C1, the left and right second chuck mechanisms C2L described with reference to FIG. C2R and left and right third chuck mechanisms C3L and C3R are respectively attached.
The plate 22A to which these are attached is detachably attached to the housing 21 by a presser fitting 23 so that it can be replaced with a plate 22B on which a planar stage 47 shown in FIGS. 6 and 7 described later is mounted. It is configured.

As shown in FIG. 2, the positive terminal 9 and the negative terminal 10 capable of obtaining a direct current output from the power supply device 25 disposed in the housing 21 are disposed on the left and right sides of the bottom portion of the plate 22A. Has been.
As described with reference to FIG. 1, lead wires are connected to the positive electrode and negative electrode terminals 9 and 10, and the positive electrode current collector and the negative electrode current collector of the pseudo power storage device S0 placed on the pipe-shaped stage 1 are connected to each other. On the other hand, a set DC voltage or DC current is supplied.

FIG. 4 shows the pipe-like stage 1 mounted on the plate 22A in a sectional view along the axial direction. A cylindrical heater 27 is embedded in the pipe-shaped stage 1 along an axial hole formed in the shaft core portion, and the surface temperature of the pipe-shaped stage 1 made of stainless steel is controlled by the heater 27. . Reference numeral 27 a shown in FIG. 4 is a lead wire of the heater 27.
The heater 27 is on / off controlled by a heater switch 28 disposed at the upper left of the front of the apparatus shown in FIG. 2, and is further operated by a temperature adjusting unit 29 disposed on the left side of the heater switch 28. The heating temperature is adjusted.

  FIG. 5 is a front view showing an example of a chuck mechanism mounted on the plate 22A. The chuck mechanism shown in FIG. 5 shows a specific example of the first chuck mechanism C1, and particularly shows a mounting structure of the movable pipe 4L disposed on the left side of the fixed pipe 3. The movable pipe 4L is mounted on a support fitting 31 formed in an L shape, and the support fitting 31 is rotated on a plate 22A by a support shaft 32 in a range of about 45 degrees. It is configured.

  The state shown in FIG. 5 shows a state in which the movable pipe 4L is separated from the fixed pipe 3, and the movable pipe 4L is shown by an imaginary line by rotating the support fitting 31 in the direction indicated by the arrow. , Contact the left side of the fixed pipe 3. Thereby, as shown in FIG. 1, the edge part of electrode material S1 can be hold | gripped by the 1st chuck mechanism C1 between the fixed pipe 3 and the movable pipe 4L.

The movable pipe 4R shown on the right side of the fixed pipe 3 shown in FIG. 5 also forms a similar chuck mechanism formed on the left and right sides, and functions so as to be able to contact and separate from the fixed pipe 3 by the same action. To do. The second left and right chuck mechanisms C2L and C2R and the third left and right chuck mechanisms C3L and C3R have the same configuration.
Each chuck mechanism described above preferably has a tension control function capable of further applying tension to the electrode material or the like while the electrode material or the like is sandwiched between the fixed pipe and the movable pipe.
According to this configuration, the situation on the stage where the negative electrode material S1, the separator S2, and the positive electrode material S3 are overlaid can be reproduced and verified as a form close to the actual battery situation.

Returning to FIG. 2, a test nail 2 is arranged directly above the pipe-shaped stage 1 so as to be movable in the vertical direction. The test nail 2 is detachably attached by a holder 35 disposed at a lower end portion of a load cell 34 capable of measuring a contact load. Note that a test nail 2 having a different diameter (for example, a diameter of 1 mm, 3 mm, 5 mm) prepared in advance can be arbitrarily selected and mounted on the holder 35.
Further, the test nail 2 having a different tip shape can be selectively mounted using the holder 35. The tip has various shapes corresponding to short-circuit accidents actually encountered in the market, such as a pointed or rounded tip, or a punch shape that punches holes in paper. Things can be used.

The load cell 34 is supported by a support member 36 as shown in FIG. 3, and the support member 36 is attached to a drive slider 37 a of an actuator 37 by a single-axis robot disposed in the housing 21, Drive controlled in the vertical direction.
Therefore, the test nail 2 can be moved (lowered) and moved backward (raised) with respect to the pseudo power storage device S0 placed on the pipe-like stage 1 by the drive control of the actuator 37.

The load cell 34 includes servo means for detecting a contact load applied to the test nail 2 by the actuator 37 and returning the information to the actuator 37. As a result, when the test nail 2 comes into contact with the stage 1, it is controlled so as to have a predetermined contact load (N = Newton).
Therefore, for example, even when evaluating a pseudo electricity storage device in which a positive electrode material, a separator, and a negative electrode material are repeated in multiple layers, the test nail 2 can surely pierce the entire layer of the pseudo electricity storage device. it can. This makes it possible to realize a highly accurate short-circuit test even for a multilayer pseudo electricity storage device.

In this case, it is also important to form a hole in the above-described stage 1 through which the tip of the test nail 2 can enter. According to this configuration, the test nail 2 can prevent the pseudo electricity storage device on the stage 1 from being inserted. Therefore, it is possible to realize a short-circuit test in which holes can be made more reliably.
In addition, it is desirable that a temperature detection element is disposed in the vicinity of the tip of the test nail 2 that is detachably attached to the holder 35 so that the temperature caused by a short-circuit due to nail penetration can be directly measured.

  As shown in FIG. 2, a touch panel 41 is disposed near the lower bottom of the front surface of the evaluation test apparatus. By operating the touch panel 41, the moving speed of the test nail 2 described above and the power source described above are set. The DC voltage value or DC current value brought from the supply device 25 to the positive electrode terminal 9 and the negative electrode terminal 10 can be set.

A main power switch 42 of the evaluation test apparatus is disposed below the touch panel 41, and an emergency stop switch 43 of an actuator 37 for driving the test nail 2 in the vertical direction is disposed on the right side of the main power switch 42. Has been.
As shown in FIG. 3, an outlet 44 for receiving AC power is disposed on a part of the side surface of the evaluation test apparatus, and a fuse box 45 is disposed above the outlet 44.

6 and 7 show the planar stage 47 mounted on the plate 22B.
As described above, the plate 22B on which the planar stage 47 is mounted is configured to be exchangeable with the plate 22A on which the pipe-shaped stage 1 and the like are mounted.
That is, rectangular cutout portions 22a are formed at the corners of the left and right bottom portions of the plate 22B, and the output terminals 9 and 10 from the power supply device 25 already described are positioned in the cutout portions 22a. In this way, it is attached by the presser fitting 23.

The planar stage 47 includes a planar pedestal 48 and a lid 49 that covers the pedestal 48 from above and is detachable from the pedestal 48. The pedestal 48 is attached to the plate 22B via an L-shaped mounting bracket 50.
An alignment pin 51 is erected on the pedestal 48, and a lid 49 is attached to the pedestal 48 using the pin 51.

On the pedestal 48 of the planar stage 47, a pseudo power storage device S0 is placed by stacking the sheet-like electrode materials S1 and S3 with the sheet-like separator material S2 in the center as in the example shown in FIG. Is done. Then, the lid 49 is placed on the pseudo power storage device S0, and a DC voltage or a DC current is supplied from the output terminals 9 and 10 to the sheet-like electrode materials S1 and S3.
In this state, as shown in FIG. 6, the test nail 2 advances toward the pedestal 48, whereby the nail penetration test already described is executed.

  In this embodiment, as shown in FIG. 6, a dust box 52 is disposed immediately below the pedestal 48, and the dust box 52 is attached to the lower bottom surface of the mounting bracket 50 described above. The dust box 52 receives debris generated in the above-described nail penetration test.

The example shown in FIG. 1 described above shows an example in which the negative electrode material S1, the separator material S2, and the positive electrode material S3 are sequentially stacked on the stage 1, and the test nail 2 is moved from the positive electrode material S3 to the negative electrode material S1. The example which stabs toward and short-circuits is shown. However, an evaluation test in which the order of these superpositions is reversed from that in the illustrated example and the test nail 2 is pierced from the negative electrode material S1 toward the positive electrode material S3 can be employed.
This is necessary because it is confirmed that the test nail 2 is also dependent on the direction of insertion from the positive electrode or negative electrode side, and the reproducibility of the evaluation test can be confirmed.

  In addition, some batteries have fillers applied to one side of the separator. According to the evaluation test apparatus described above, the filler application surface is applied to the positive electrode material S3 side or the negative electrode material S1 side. Verification that compares which is safer can also be realized.

Moreover, in the evaluation test method described above, it has been described that the evaluation test is performed using the electrode material at the material stage before the assembly of the battery, that is, the electrode material before charging, the evaluation test method according to the present invention, A positive and negative electrode material can be taken out from a battery that has been completed and charged, and can be evaluated with a charged electrode.
In this case, the positive and negative electrode materials taken out from the charged battery are used as evaluation samples after the electrolytic solution is removed by washing and dried.
According to this, it can be positioned as a precise evaluation in a state closer to reality than assumed a charged battery.

  Note that the examples shown in FIGS. 1 to 7 used in the above description are preferable examples, and the safety evaluation test method and the safety evaluation test apparatus according to the present invention do not depart from the scope of the claims. It can be easily understood that various modifications can be made within the scope.

DESCRIPTION OF SYMBOLS 1 Pipe-shaped stage 2 Test nail 3 Fixed pipe 4L, 4R Movable pipe 5L, 5R Fixed pipe 6L, 6R Movable pipe 7L, 7R Fixed pipe 8L, 8R Movable pipe 9, 10 Output terminal 11, 12 Lead wire 13, 14 Hook clip 21 Housing 22A, 22B Plate 22a Notch 23 Presser Bracket 25 Power Supply Device 27 Heater 27a Lead Wire 28 Heater Switch 29 Temperature Control Unit 31 Supporting Bracket 32 Spindle 34 Load Cell 35 Holder 36 Support Member 37 Actuator 37a Drive Slider 41 Touch Panel 42 Main power switch 43 Emergency stop switch 44 AC power outlet 45 Fuse box 47 Planar stage 48 Base 49 Lid 50 Mounting bracket 51 Alignment pin 52 Dust box C1 First Click mechanism C2L, C2R second chuck mechanism C3L, C3R third chuck mechanism S0 pseudo storage device S1 negative electrode material S2 separator material S3 positive electrode material

The safety evaluation test method for an electricity storage device according to the present invention made to achieve the above-described problem uses a pseudo electricity storage device by a combination of an electrode material and a separator without using an electrolytic solution, and the electrode material and the separator A method for evaluating the safety of an electricity storage device for quantitatively confirming the safety of the electricity storage device when using a battery , comprising: a positive electrode current collector and a sheet-like positive electrode material including a positive electrode active material layer; Forming a pseudo electricity storage device by interposing a sheet-like separator material or a sheet-like solid electrolyte between the body and the sheet-like negative electrode material including the negative electrode active material layer and superposing them on the stage; Supplying a predetermined voltage or current between the positive electrode current collector and the negative electrode current collector of the pseudo electricity storage device, and a test nail is advanced toward the stage. And the step of short-circuiting the positive electrode current collector and the negative electrode current collector by passing through the pseudo power storage device by the test nail, the short circuit between the positive electrode current collector and the negative electrode current collector It is characterized in that it is verified whether or not the electrode material of the pseudo electricity storage device shifts to a combustion state.

On the other hand, the safety evaluation test apparatus for an electricity storage device according to the present invention made to achieve the above-described problem uses a pseudo electricity storage device by a combination of an electrode material and a separator without using an electrolyte solution, and the electrode material Is a storage device safety evaluation test apparatus for quantitatively confirming the safety of an electricity storage device when using a separator, a sheet-like positive electrode material including a positive electrode current collector and a positive electrode active material layer, and a negative electrode A pseudo electricity storage device configured by stacking a sheet-shaped separator material or a sheet-shaped solid electrolyte between a current collector and a sheet-shaped negative electrode material including a negative electrode active material layer is placed. A power supply device for supplying a predetermined voltage or current between a stage and a positive electrode current collector and a negative electrode current collector of the pseudo power storage device; Proceeds Te, by penetrating the pseudo electric storage device, the and the test nail can be short-circuited and a positive electrode current collector and the anode current collector is provided.

Claims (14)

Between the sheet-like positive electrode material including the positive electrode current collector and the positive electrode active material layer and the sheet-like negative electrode material including the negative electrode current collector and the negative electrode active material layer, A step of forming a pseudo electricity storage device by interposing a solid electrolyte and being superimposed on a stage;
Supplying a predetermined voltage or current between the positive electrode current collector and the negative electrode current collector of the pseudo electricity storage device;
A step of moving the test nail toward the stage and shorting the positive electrode current collector and the negative electrode current collector by penetrating the pseudo electricity storage device by the test nail;
Is performed, and it is verified whether or not the electrode material of the pseudo power storage device shifts to a combustion state due to a short circuit between the positive electrode current collector and the negative electrode current collector. .   2. The method for evaluating safety of an electricity storage device according to claim 1, wherein the positive electrode material and the negative electrode material are taken from a charged battery and the electrolyte is removed.   The method for evaluating and evaluating the safety of an electricity storage device according to claim 1 or 2, wherein a pipe-like stage or a planar stage is used as a stage on which the pseudo electricity storage device is placed.   4. The verification according to claim 1, wherein the verification is performed by changing a voltage value or a current value supplied between the positive electrode current collector and the negative electrode current collector. 5. Safety evaluation test method for electricity storage devices.   The safety evaluation test method for an electricity storage device according to any one of claims 1 to 3, wherein the verification is performed in a state where the stage is heated or cooled.   4. The verification according to claim 1, wherein the verification is performed by using a plurality of test nails having different diameters or a plurality of test nails having different tip shapes as the test nails. 5. Safety evaluation test method for electricity storage devices.   The method for evaluating safety of a power storage device according to any one of claims 1 to 3, wherein the verification is performed by varying a traveling speed of the test nail toward the stage. Between the sheet-like positive electrode material including the positive electrode current collector and the positive electrode active material layer and the sheet-like negative electrode material including the negative electrode current collector and the negative electrode active material layer, A stage on which a pseudo electricity storage device configured by stacking with a solid electrolyte interposed therebetween,
A power supply device that supplies a predetermined voltage or current between the positive electrode current collector and the negative electrode current collector of the pseudo electricity storage device;
A test nail that can be short-circuited between the positive electrode current collector and the negative electrode current collector by proceeding toward the stage side and penetrating the pseudo electricity storage device;
A safety evaluation test apparatus for an electricity storage device, comprising:   The safety evaluation test apparatus for an electricity storage device according to claim 8, wherein a pipe-like stage or a planar stage is configured to be replaceable as a stage on which the pseudo electricity storage device is placed.   The plate to which the pipe-shaped stage is attached is provided with a chuck mechanism that holds both ends of the positive electrode material, the separator material, and the negative electrode material. Safety evaluation test equipment for electricity storage devices.   The power supply device is configured so that a voltage value or a current value supplied between the positive electrode current collector and the negative electrode current collector can be changed. The safety evaluation test apparatus for the electricity storage device according to 1.   The safety of the electricity storage device according to claim 8 or 9, wherein a heater or cooling means capable of heating or cooling a stage on which the pseudo electricity storage device is placed is disposed in the stage. Sex evaluation test equipment.   The test nail is detachably attached to a holder that advances and retreats toward the stage side, and the holder is configured so that a test nail having a different diameter or a test nail having a different tip shape can be attached thereto. 10. The safety evaluation test apparatus for an electricity storage device according to claim 8 or 9, wherein   The safety evaluation test apparatus for an electricity storage device according to claim 8 or 9, wherein a traveling speed of the test nail toward the stage is controllable.

Images