JP2013157158A - Layer-built battery and layer-built battery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such problems of a conventional wound battery that temperature rise in the battery cannot be suppressed, that the wound battery does not function as a battery when the temperature of an electrode rises, and that the battery dimensions increase when a pipe, or the like, for feeding a cooling medium is provided in the battery.SOLUTION: In a nonaqueous battery, heat transmission of an electrode is enhanced by laminating positive electrodes and negative electrodes in the axial direction of a hollow battery exterior body, thereby making the outer diameter of one of the positive electrode or negative electrode larger than the inner diameter of the exterior body so that the positive electrode or negative electrode comes into tight contact with the exterior body.

Description

  The present invention relates to a cooling structure for a non-aqueous battery. Specifically, the present invention relates to a battery cooling structure with improved cooling performance in a non-aqueous battery.

  Various types of batteries such as cylindrical batteries and prismatic batteries have been developed and widely used as storage batteries. In addition, a cylindrical type is adopted for a relatively small capacity battery from the viewpoint of pressure resistance and ease of sealing, and a square type is adopted for a relatively large capacity battery for ease of handling.

  If attention is paid to the electrode structure of the storage battery, two types, a stacked type and a wound type, are widely used. That is, in a stacked battery, an electrode group in which positive and negative electrodes are alternately stacked via separators is housed in a battery case. Many of the stacked type batteries have a rectangular battery case. On the other hand, the wound type is housed in a battery case in a state in which the positive electrode and the negative electrode are wound in a spiral shape with a separator interposed therebetween. The wound type battery case may be a cylindrical type or a square type.

  Patent Document 1 and Patent Document 2 disclose techniques related to a cylindrical wound battery. That is, in FIG. 1, the storage battery 1 mainly includes a positive electrode 3, a negative electrode 4, a separator 5, and an electrolytic solution disposed in a battery case 2. The battery case 2 is a substantially cylindrical container having an opening 2a in the upper part, and the bottom part thereof is set as a negative electrode terminal. The strip-shaped positive electrode 3 and the negative electrode 4 are disposed in the battery case 2 in a state of being wound in a spiral while sandwiching the separator 5. Further, the opening 2 a of the battery case is sealed in a liquid-tight manner by the sealing plate 7 in a state where the electrolytic solution is injected into the battery case 2. The cap 6 provided on the upper surface of the sealing plate 7 serves as a positive electrode terminal. The positive electrode terminal is connected to the positive electrode 3 by a lead wire (not shown). As described above, the cylindrical wound battery is a battery having a relatively small capacity.

  Various methods for cooling the storage battery have been proposed. Most of them relate to an assembled battery obtained by combining a plurality of storage batteries into a module. This is because when the storage battery is modularized to increase the capacity, the temperature rise of the storage battery becomes a problem. As for the cooling structure of the assembled battery, a method of improving the heat dissipation by providing a protrusion on the surface of the container containing the assembled battery to cause a disturbance in the flow of the cooling air (for example, Patent Document 3) A method of providing a cooling air passage with a metal cooling plate with a hole in between (for example, Patent Documents 3 and 4) or a method of providing a cooling fin protruding outside the storage container (for example, Patent Document 5) Etc. have been proposed.

In Patent Document 6, in a prismatic laminated battery unit in which a separator is interposed between a positive electrode and a negative electrode, a cooling plate is provided between the battery units, and a battery flow path is provided on the cooling plate. A cooling structure for a laminate is disclosed.
Patent Document 7 discloses a technique of a cylindrical wound battery in which a sheet-shaped heat sink is disposed on a positive electrode and a negative electrode and wound together with a separator.

For non-aqueous secondary batteries, such as lithium secondary batteries, 4V positive electrode materials (LiCoO ₂ , LiMn ₂ O ₄ etc.) and graphite negative electrode materials, microporous membrane separators to prevent micro shorts, up to 4.5V Organic electrolytes that can withstand high voltages are used.

Since commercialization, the capacity of lithium secondary batteries has improved more than twice. For example, the capacity of the cylindrical battery for personal computers (18650), which was 1200 mAh in 1994, has increased to 2200 mAh in 2002 and 2900 mAh in 2006. It is approaching the limit, and the accident of battery ignition has been reported.
It is said that the lithium secondary battery ignition mechanism is as shown in (1) to (6) below (for example, Non-Patent Document 2).
(1) Li dendrite and impurity metals (Cu, Fe, Ni, etc.) are deposited on the graphite negative electrode at the end of charging, causing a micro short circuit, and the temperature rises.
(2) The reaction between the negative electrode surface coating and the electrolyte starts from around 80 ° C., the temperature rises, and the PCT element, which is a safety device, operates to cut off the current.
(3) Decomposition of the electrolyte starts from around 80 ° C. and gas is generated, and the pressure valve, which is a safety device, operates to cut off the current.

(4) At 120 ° C. or higher, the microporous membrane separator made of polyethylene or polypropylene closes and the reaction is cut off (the shutdown function is activated), and the current is cut off.
(5) However, at 160 ° C. or higher, the separator dissolves, causing a short circuit and generating heat.
(6) Furthermore, at 220 ° C. or higher, the positive electrode material (LiCoO ₂ , LiMn ₂ O _4, etc.) is thermally decomposed to release oxygen and react with the organic solvent to cause a rapid temperature increase.
Therefore, it is required to achieve both high battery capacity and safety.

JP 2002-198044 A JP 2004-103350 A JP 2009-016285 A JP 2003-007355 A JP 2001-143769 A International Publication No. 2008/099609 Japanese Patent Laid-Open No. 11-144771

Proceedings of the 52nd Battery Symposium (2B19) “High output of LiFePO4 positive electrode” 2011 KEC Information Special Issue on Next Generation Batteries (Latest Rechargeable Battery Trends and Future Developments), No. 215, pp. 2-8. October 2010 issue.

  The separator, which is one of the components of non-aqueous secondary batteries, prevents the short circuit between the positive and negative electrodes, holds the electrolyte, and also exhibits a shutdown function at high temperatures (about 120 ° C), thus ensuring battery safety Although it is an important part that enhances the properties, it uses polyethylene, polypropylene, and other films as its material, so its thermal conductivity is small compared to the positive and negative electrodes, and it is difficult to transfer heat.

  Referring to cooling of the wound battery shown in FIG. 1, it is necessary to conduct heat in a direction (radial direction) perpendicular to the stacking direction (circumferential direction) of the electrode and separator. It is difficult to transfer heat well through the separator. FIG. 2 is a schematic diagram for explaining the state of the temperature gradient inside the battery from the battery surface (case) toward the center. According to FIG. 2, in the cylindrical wound battery, the case and the electrode have a high thermal conductivity, so a large temperature gradient does not occur. However, the separator has a low thermal conductivity, and thus a large temperature gradient is generated. It turns out that it is.

That is, although the surface temperature of the battery case of the wound battery is close to the ambient temperature, the temperature of the central portion is high, and particularly in the charge / discharge state, the temperature is considerably high. Even if the outside of the battery case is cooled, the temperature inside the battery is not cooled to a necessary level. The electrolyte decomposes at 80 ° C. or higher to generate gas, and the pressure valve, which is a safety device, is activated to cut off the current. In general, in an electrolytic solution used in a lithium secondary battery (for example, propylene carbonate or ethylene carbonate in which a LiPF ₆ salt is dissolved), the electrolytic solution is vaporized or decomposed at 80 ° C. or higher to generate gas. On the other hand, when the temperature rises, the separator shuts down and loses the battery function. In general, in a separator used in a lithium secondary battery (for example, a polyethylene microporous membrane, a polypropylene microporous membrane, etc.), when the temperature reaches about 120 ° C., the material is thermally contracted to close the pores, Hinder the flow of current between them. Further, the deterioration of the electrode is promoted under a high temperature environment.

  As a method for cooling the battery, a method of providing protrusions on the surface of the battery case to improve heat dissipation (for example, Patent Document 3), or providing a metal plate with holes between the assembled batteries to flow cooling air and cooling it (For example, Patent Documents 3 and 4) or a method for providing cooling fins (for example, Patent Document 5) have been proposed, both of which are effective for cooling the surface of the battery case, Since there is a temperature gradient due to the separator, it cannot be an effective cooling method in a wound battery.

  A method of winding a heat sink together with an electrode (for example, Patent Document 7) and a method of storing a pipe through which cooling water flows in the battery have been proposed. These methods may be said to be more effective cooling methods than cooling the surface of the battery case, but require a space for cooling, increase the battery size, and decrease the electric capacity per volume.

Lithium secondary batteries are mainly used for portable devices, and high-capacity LiCoO ₂ cathodes are used. In 2010, 18,000 MWh batteries are expected to be produced. Co is about 20,000 tons (about 30% of world production) ) Required. Thus, for automobiles, manganese-based LiMn ₂ O ₄ is used from the viewpoint of resources and cost, but Mn elutes into the electrolyte at high temperatures, and the material itself lacks thermal durability.

Since the amount of Joule heat is determined by the product of the square of the resistance R and the current I, heat is generated inside the battery by Joule heat when a current is passed through the battery, not limited to non-aqueous secondary batteries. If the battery has a low capacity, the heat is discharged to the outside of the battery system over time, so that the rise in battery temperature can be suppressed to some extent. However, even in a low-capacity battery, if charging / discharging is performed with a large current density, the inside of the battery is likely to be stored by Joule heat, and this tendency increases as the capacity increases.
Therefore, when the inside of the battery is stored, the deterioration of the battery is promoted and the safety is also lowered.

  A discharge rate is known as an index for evaluating input / output characteristics of a secondary battery. The discharge rate is an index based on a constant current discharge of a cell having a capacity of a nominal capacity value and setting the current value at which discharge is completed in 1 hour as “1C rate”. The current value at which discharge ends is expressed as “0.2 C rate”, and the current value at which discharge ends after 10 hours is expressed as “0.1 C rate”.

Lithium iron phosphate (LiFePO ₄ ) is being adopted as a lithium-containing transition metal oxide to replace lithium cobaltate (LiCoO ₂ ), spinel type lithium manganate (LiMn ₂ O ₄ ), etc. due to its high input / output characteristics. . However, it is an electrode having such high input / output characteristics (in terms of mass% ratio, LiFePO ₄ : KB: PVdF = 83: 5: 12, electrode thickness: 65 μm, capacity density: 0.8 mAh / cm ² ) However, the discharge rate stays below the 5C rate. Since the discharge rate is higher as the current density is smaller, at present, the electrode thickness has to be reduced to obtain high input / output characteristics, and the electrode capacity per cell is reduced.

Therefore, for example, in Non-Patent Document 1, each additive, binder, current collector, and the like are optimized to increase the output of the LiFePO ₄ positive electrode. However, when charging or discharging is performed at high speed, the battery temperature is In order to accelerate the deterioration of the electrode at a high temperature, a battery structure with excellent heat dissipation is required.

  The present invention has been made to solve such a problem, and provides a battery that suppresses a temperature rise inside the battery and does not require an extra space in the battery for cooling. Furthermore, even if charging / discharging is performed with a large current density, it is possible to prevent deterioration of the battery.

  In order to achieve the above-described object, the laminated battery according to the present invention includes a positive electrode containing a positive electrode active material and a negative electrode containing a negative electrode active material in a cylindrical outer package, which transmit ions but transmit electrons. A battery that is laminated in the axial direction of the outer package through a non-permeable separator and includes an electrolyte solution containing a non-aqueous electrolyte, and is either the positive electrode or the negative electrode. A first electrode that is in contact with and electrically connected to the inner surface of the exterior body; and a second electrode that is the other electrode and that is not in contact with the inner surface of the exterior body. The electric body passes through the positive electrode, the negative electrode, and the separator in the axial direction of the outer package, and the second electrode is in contact with and electrically connected to the current collector, The electrode is not in contact with the current collector (Claim 1 / FIG. 3).

  According to this configuration, the separator holds the non-aqueous electrolytic solution, insulates between the positive and negative electrodes, and enables the permeation of ions. The exterior body is made of metal and functions as a terminal of the electrode (first electrode) in contact with the exterior body. The positive and negative electrodes and the separator are preferably formed in a sheet shape. The exterior body is hollow, and each electrode is stacked in the axial direction of the exterior body and accommodated inside the exterior body. The outer dimension (dimension in the direction perpendicular to the thickness direction) of the first electrode is made slightly larger than the inner diameter of the exterior body. The first electrode is in contact with the entire inner surface or part of the outer surface of the exterior body. When the first electrode is pressed into the exterior body, the first electrode contacts the exterior body and is not only electrically connected, but also thermally connected to the exterior body with a small resistance, It works effectively to cool the electrode.

  On the other hand, the outer diameter of the second electrode is made smaller than the inner diameter of the exterior body, and the second electrode is insulated without contacting the exterior body. The outer package may be a can, preferably iron (Fe), copper (Cu), nickel (Ni), aluminum (Al), titanium (Ti), chromium (Cr), gold (Au), stainless steel. It may be a metal such as conductive glass, carbon (C) or polymer, but from the viewpoint of thermal conductivity and electronic conductivity, iron, copper, nickel, aluminum, gold, Stainless steel or the like is preferable. In addition, when a 1st electrode is a positive electrode, although it changes with active materials to be used, an aluminum, stainless steel, etc. are preferable from a viewpoint of oxidation resistance. When the first electrode is a negative electrode, copper, nickel, stainless steel, and the like are preferable from the viewpoint of reduction resistance, although depending on the active material used.

  The heat generated in the first electrode is directly transferred to the exterior body. The thermal gradient (temperature difference) is small because there is no defective conductor on the way. Heat generated in the second electrode is transmitted to the first electrode through the separator. A separator having a low thermal conductivity is interposed in the middle, but only one sheet does not provide a large thermal resistance, so the thermal gradient can be kept small. Furthermore, the second electrode is strongly pressed against the first electrode by pushing the electrode group consisting of the positive and negative electrodes and the separator into the exterior body with a large pressure in the axial direction, so that the heat transfer of the second electrode becomes larger. . The temperature gradient of the wound battery is large because the separator between the outer body and the electrode, which is difficult to transfer heat, is interposed between the outer body and the electrode. This is because it is not possible to increase the movement of.

The overall heat transfer coefficient (U ₁ ) of the wound battery is expressed by Equation 1, and the overall heat transfer coefficient (U ₂ ) of the laminated battery according to the present invention is expressed by Equation 2. When both are compared, it can be seen that there is a large difference in the term indicated by the underline. Although specific numerical values will be described in detail in the embodiment, the overall heat transfer coefficient decreases as the winding number (n) of the wound battery increases.

  As described above, the temperature gradient of the laminated battery according to the present invention is small, and the temperature rise at the center of the laminated battery can be reduced. For this reason, since it is not necessary to provide a pipe or the like for flowing a refrigerant inside the battery, the temperature rise can be suppressed with a compact structure. Furthermore, since the exterior body can be cooled relatively easily, the temperature rise can be effectively suppressed.

In addition, since the second electrode is in contact with and electrically connected to the current collector, and the first electrode is not in contact with the current collector, the positive and negative electrodes and the separator are each collected at the central portion thereof. The electric body has a hole through which the current collector passes through the hole. The diameter of the hole of the first electrode is larger than the outer diameter of the current collector, so that the first electrode does not contact the current collector, and the diameter of the hole of the second electrode is smaller than the outer diameter of the current collector, For this reason, the second electrode is in electrical contact with the current collector.
The current collector functions as a terminal of the second electrode. The current collector is not particularly limited as long as it is a material having electron conductivity.
According to this configuration, the electrolytic solution is a non-aqueous electrolytic solution, and the organic electrolytic solution corresponds to this. An electrolytic solution composed of an alkaline aqueous solution is a typical example of an aqueous electrolytic solution.

  Non-aqueous secondary batteries include lithium secondary batteries, sodium secondary batteries, magnesium secondary batteries, calcium secondary batteries, etc., and lithium ion capacitors, sodium ion capacitors, magnesium ion capacitors, and calcium ion capacitors are also non-aqueous. Included in secondary batteries.

  In the laminated battery according to the present invention, a groove is formed on the side surface of the current collector (Claim 2), and the groove of the current collector is a screw groove, and the diameter of the valley of the screw is the second. The diameter of the current collector provided on the electrode is larger than the diameter of the hole (Claim 3 / FIG. 4).

  According to this configuration, the side surface of the current collector is grooved. The groove may be a screw groove, the diameter of the hole provided in the second electrode is smaller than the outer diameter of the screw valley of the current collector, and the diameter of the hole provided in the first electrode is the screw of the current collector. Larger than the outer diameter of the pile. By making the diameter of the hole provided in the second electrode smaller than the outer diameter of the screw valley of the current collector, it is possible to ensure sufficient contact between the second electrode and the current collector.

  If the current collector is not subjected to thread groove processing, the connection between the current collector and the electrode may be loosened when the electrode is assembled, and the current collector and the electrode may not be kept in close contact with each other. In order to solve such a problem, the current collector was subjected to thread groove processing. That is, a strong fitting state is maintained between the second electrode and the current collector along the lead of the screw. As a result, it is possible to prevent the electrode from coming off the current collector during assembly processing.

  In the laminated battery according to the present invention, the current collector and the second electrode are joined by an adhesive (Claim 4). And preferably, the adhesive is composed of a resin that does not dissolve in the electrolytic solution and carbon powder, and when the mixing ratio is 100% by mass, the resin that does not dissolve in the electrolytic solution is 30 to 90% by mass, Carbon powder is 10-70 mass% (Claim 5). Further, the resin that does not dissolve in the electrolytic solution is more preferably polyimide (Claim 6).

Even if the diameter of the hole provided in the second electrode is larger than the outer diameter of the screw valley of the current collector by joining the current collector and the second electrode with a conductive adhesive, In addition, it is possible to ensure contact between the second electrode and the current collector.
Furthermore, by joining the current collector and the second electrode with an adhesive, it is possible to reliably prevent the electrode from falling out of the current collector during assembly processing.

  The reason why the resin that does not dissolve in the electrolytic solution is limited to 30 to 90% by mass is that the carbon powder is bulky if it is less than 30% by mass, so that it is difficult to ensure sufficient adhesiveness, and 90% by mass. When exceeding, it is because it is difficult to ensure sufficient conductivity even if carbon powder is mixed. Therefore, the resin that does not dissolve in the electrolytic solution is preferably 30 to 90% by mass, and more preferably 50 to 70% by mass. Similarly, it is preferable that carbon powder is 10-70 mass%, and it is more preferable that it is 30-50 mass%.

  The resin that does not dissolve in the electrolytic solution only needs to be stable and maintain adhesiveness with respect to the electrolytic solution. From this viewpoint, CMC, PVA, polyacryl, polyimide, polyamide, and polyamideimide are preferable. Among these, polyimide is preferable from the viewpoint of heat resistance.

  In the laminated battery according to the present invention, the exterior body may be a bottomed cylinder with a lid (Claim 7 / FIG. 3), and the exterior body has a bottomed container having a substantially rectangular cross section; You may provide the cover member which covers the opening part of a container (Claim 8 / FIG. 8). According to this configuration, the exterior body may be a can.

  The stacked battery system according to the present invention is configured by stacking a plurality of stacked batteries in series, in which the bottom of the container of the stacked battery and the lid member of the adjacent stacked battery are opposed to each other (claim) Item 9 / FIG. 9).

The battery system according to the present invention may be one in which a bottom portion of the container of the multilayer battery and a lid member of the adjacent multilayer battery are in contact with each other, and a plurality of multilayer batteries are stacked to be connected in series. .

According to this configuration, one lid member of two stacked batteries and the bottom of the container of the other stacked battery are brought into contact with each other, and are stacked and electrically connected in series. If a plurality of laminated batteries are connected in this way, the output voltage of the battery system (assembled battery) increases according to the number of connections.

  In the laminated battery according to the present invention, the exterior body includes a cylindrical metallic body portion and two lid portions covering the axial opening of the body portion, and the current collector is the lid portion. (Claim 10 / FIG. 10).

  According to this configuration, the current collector may pass through the lid portion and be supported by the lid portions at both ends. The exterior body may be provided with lids at both end openings of a circular pipe (pipe). The exterior body is formed of a circular tube and a lid to form a sealed space therein. An electrode group including positive and negative electrodes and a separator is housed in the sealed space. The lid may be made of metal. The outer diameter of the first electrode is made slightly larger than the inner diameter of the outer package, and the outer diameter of the second electrode is made smaller than the inner diameter of the outer package.

  The connection fitting according to the present invention is a columnar metal connection fitting arranged between stacked batteries, and the connection fitting is provided with a connection hole in the axial direction on the bottom and top surfaces of the connection fitting. The end of the current collector of one stacked battery can be fitted into the provided connection hole, and the end of the current collector of the other stacked battery is the insulator in the connection hole provided in the bottom surface. Can be fitted to each other, and adjacent stacked batteries can be connected to each other (claim 11).

  The connection fitting may be a cylinder or a prism, and the bottom and top surfaces of the connection fitting can be in contact with the lid portions of the laminated batteries adjacent to each other. By fitting the current collector into the hole provided on the upper surface, the current collector of one stacked battery and the lid of the other stacked battery are mechanically connected and electrically connected. In addition, since the insulator is interposed between the hole provided on the bottom surface and the current collector, the current collectors of the adjacent stacked batteries are insulated from each other. By using the connection fitting, it is possible to connect the stacked batteries in series.

  The laminated battery system according to the present invention is formed by connecting a plurality of laminated batteries via the connection fittings (claim 12). That is, in the laminated battery, a plurality of laminated batteries can be connected in series by fitting the current collector penetrating the first lid portion into the connection hole of the adjacent laminated battery.

  According to this configuration, a plurality of stacked batteries are connected in series via the connection fitting by fitting the current collector penetrating the lid portion into the connection hole of the adjacent stacked battery. And the terminal voltage of a laminated battery system becomes large according to the number of the laminated batteries connected.

  In the laminated battery according to the present invention, the exterior body includes a cylindrical metallic trunk, and an insulating first lid and a second lid that cover the axial opening of the trunk. The current collector includes a rod portion and a stop portion formed at one end of the rod portion, and the rod portion penetrates the positive electrode, the negative electrode, and the separator in the axial direction of the exterior body, and the rod The other end of the part is supported by the first lid part, and the stopper part is in contact with the second lid part (Claim 13).

  According to this structure, the 1st cover part and the 2nd cover part cover the opening part of the both ends of a trunk | drum, and an exterior body forms sealed space in the inside by the trunk | drum and lid part. In addition, an electrode group composed of positive and negative electrodes and a separator is housed in a sealed space. As described above, the outer diameter of the first electrode is made slightly larger than the inner diameter of the outer package, and the outer diameter of the second electrode is made smaller than the inner diameter of the outer package.

  The stop portion having an outer diameter larger than that of the rod portion makes it possible to prevent the electrode group from falling off the current collector. Since the stop portion is in contact with the second lid portion, movement of the current collector in the axial direction is limited.

  The laminated battery system according to the present invention is a laminated battery system in which a plurality of laminated batteries are connected via a metal bracket, the bracket having two holes, and one of the adjacent laminated batteries. The trunk portion is attached to one hole of the bracket, the rod portion of the other laminated battery is attached to the other hole of the bracket, and adjacent laminated batteries are connected in series via the bracket. (Claim 14).

  According to this configuration, the bracket is a plate-like metal, and may be iron, copper, aluminum, nickel, titanium, or stainless steel, and the iron is subjected to nickel plating, copper plating, aluminum plating, or the like. There may be. The bracket serves as a structure for assembling the laminated batteries, serves to electrically connect adjacent laminated batteries, and further serves as a heat sink for the laminated batteries. The cooling capacity can be increased by sending cooling air to the bracket with a fan or the like. It is possible to increase the output voltage by connecting the stacked batteries one after another using a plurality of brackets to increase the number of stacked batteries in series.

  In the laminated battery according to the present invention, the exterior of the battery case is formed through a separator in which a positive electrode including a positive electrode active material and a negative electrode including a negative electrode active material transmit ions but do not transmit electrons. A first electrode that is laminated in the axial direction of the body, and is one of the positive electrode and the negative electrode that is in contact with and electrically connected to the inner surface of the exterior body, and the other electrode. And a second electrode not in contact with the inner surface of the outer package, wherein the first electrode is a negative electrode and the second electrode is a positive electrode, and the second electrode is a negative electrode. A laminated battery combining a second laminated battery in which the first electrode is a positive electrode, wherein the conductive first current collector and the second current collector connect the positive electrode, the negative electrode, and the separator to the outer package. The first current collector is inserted in the axial direction of the The second current collector is in contact with and electrically connected to the positive electrode and is not in contact with the negative electrode. It may be a structure (claim 15).

  According to this configuration, the positive electrode, the negative electrode, and the separator are each provided with two holes, the positive electrode of the first stacked battery is connected to the second current collector, and the negative electrode is the first collector. It is connected to an electric body. In addition, the positive electrode of the second stacked battery is connected to the second current collector, and the negative electrode is connected to the first current collector. Thereby, the 1st current collector functions as a negative electrode terminal, and the 2nd current collector functions as a positive electrode terminal.

The outer dimension of the first electrode is made slightly larger than the inner diameter of the outer package. Preferably, the first electrode is in contact with the inner surface of the outer package on the entire outer periphery thereof, but partially on the front periphery. It may be in contact. This is because the first electrode is electrically connected to the exterior body.
In the laminated battery according to the present invention, the outer package may be a bottomed cylinder. If a can is used for the outer package, assembly of the laminated battery is facilitated.

  In the multilayer battery according to the present invention, the first current collector is in contact with the first exterior body of the first multilayer battery, and the second current collector is the second exterior body of the second multilayer battery. The first exterior body and the second exterior body may be connected via an insulator (claim 17).

According to this configuration, the exterior body (first exterior body) of the first multilayer battery is in contact with and electrically connected to the negative electrode, and the exterior body (second exterior body) of the second multilayer battery is in contact with the positive electrode. It will be electrically connected. In this case, the exterior body of the first multilayer battery and the exterior body of the second multilayer battery are insulated from each other via an insulator, so that the exterior body of the first multilayer battery functions as a negative electrode terminal. The exterior body functions as a positive electrode terminal.
In the laminated battery according to the present invention, the inner surface of the outer package may be an insulating material having high thermal conductivity.

According to this configuration, the entire exterior body may be an insulating material having high thermal conductivity. Alternatively, the exterior body may have a double structure in which an insulating material having high thermal conductivity is provided on the inside and a structural material such as stainless steel, aluminum, copper, nickel, chromium, or iron is provided on the outside. Examples of the insulating material having high thermal conductivity include ceramics such as alumina, titania, zirconia, and alumina / titania. These ceramics have good insulation and dielectric strength (about 100 V / mm), high thermal conductivity (about 7 × 10 ⁻³ cal / cm / sec · ° C.), and large mechanical strength (Rockwell hardness of 50 or more). . Diamond may be used as the insulating material having high thermal conductivity. The structural material may be titanium, nickel, copper, chromium, carbon, aluminum, etc. in addition to stainless steel.

  In the laminated battery system according to the present invention, a plurality of the laminated batteries are arranged between current collector plates provided opposite to each other, and one positive electrode terminal connected to the positive electrode of the laminated battery is disposed on one of the current collector plates. The negative electrode terminal connected to the negative electrode of the laminated battery is in contact with and electrically connected to the other current collector plate. A means for sending cooling air in a direction parallel to the current collector plate may be provided.

  According to this configuration, the current collector plate serves as a structural material of the battery system, serves as a member for electrically connecting the stacked batteries, and acts as a heat sink. If cooling air is sent to the current collector plate from a blower or the like, it is effective for cooling the laminated battery.

  In the laminated battery according to the present invention, ions are transmitted between a positive electrode containing a positive electrode active material and a negative electrode containing a negative electrode active material inside a cylindrical outer package made of an insulating material having high thermal conductivity, but electrons are transmitted. A plurality of electrode bodies configured by interposing a non-permeable separator are laminated in the axial direction of the exterior body, and a metal partition is provided between the adjacent electrode bodies, and the positive electrode The negative electrode and the partition are in contact with the inner surface of the exterior body (claim 21). In the laminated battery according to the present invention, the outer package may be a bottomed cylinder with a lid (Claim 22).

  According to this configuration, the entire exterior body may be an insulating material having high thermal conductivity. Alternatively, the exterior body may have a double structure in which an insulating material having high thermal conductivity is provided on the inside and a structural material such as stainless steel, aluminum, copper, nickel, chromium, or iron is provided on the outside. Examples of the insulating material having high thermal conductivity include ceramics such as alumina, titania, zirconia, and alumina / titania. Diamond may be sufficient. The structural material may be titanium, nickel, copper, chromium, carbon, or aluminum in addition to stainless steel.

  In addition, the outer diameter of the positive electrode and the negative electrode is made larger than the inner diameter of the outer package, and both the positive electrode and the negative electrode are in close contact with the outer package, so that the heat generated at the positive electrode and the negative electrode has a high heat transfer rate. It is transmitted to the body and it becomes possible to suppress the temperature rise inside the laminated battery. Such a situation is as described in the means for solving the problem according to claim 1.

  The partition wall is disposed between electrodes composed of a positive electrode, a negative electrode, and a separator. Metal barriers allow electrons but not ions. Therefore, the output voltage of the laminated battery increases depending on the number of positive and negative electrode layers.

  The laminated battery according to the present invention includes a pressing plate disposed at both ends of an electrode group composed of the positive and negative electrodes and the separator stacked in the axial direction of the exterior body, and the electrode group is held by the pressing plate. Item 23).

  According to this structure, the electrode group which laminated | stacked the positive electrode, the negative electrode, and the separator between two push plates is arrange | positioned. This pressing plate prevents the electrode from dropping off from the current collector during assembly of the electrode, thereby improving workability. And after an assembly, it plays the role which maintains the compression state of an electrode group.

  The laminated battery according to the invention is preferably a lithium secondary battery (claim 24). The nonaqueous laminated battery is preferably a lithium secondary battery. By using lithium ions, the operating potential and the discharge capacity can be increased.

In the laminated battery according to the present invention, the positive electrode contains lithium iron phosphate (LiFePO ₄ ) with CMC as a band (Claim 25). CMC is an abbreviation for carboxymethylcellulose. Since the LiFePO ₄ positive electrode using CMC as a binder uses CMC as a binder, there is little binder swelling due to the electrolyte even under a high temperature environment, and an electrode can be produced without using an organic solvent. Therefore, even in a high temperature environment, high output characteristics can be maintained, and the binder is preferable from the viewpoint of cost and environment. For example, in the case of a LiFePO ₄ positive electrode using polyvinylidene fluoride (PVdF) as a binder, PVdF swells in a high-temperature environment, so that the impedance of the electrode increases. Therefore, it is preferable to use CMC because the output characteristics and cycle life characteristics of the battery are degraded. Further, by using LiFePO ₄ as an active material, there is no oxygen release due to decomposition of the active material even in a high temperature environment, and high temperature durability is improved. For the binder, SBR, PVA, fluororesin, acrylic resin, or the like may be added to CMC to increase the strength of the binder. The positive electrode is composed of an active material, a binder, and a conductive agent added as necessary. When the mixing ratio is 100% by mass as a whole, the active material is 75 to 98% by mass and the binder is 2 to 25% by mass. The conductive agent is preferably 0 to 10% by mass.

In the method for assembling the laminated battery according to the present invention, the separator is inserted into a round bar having the same outer diameter as that of the thread valley formed on the side surface of the current collector so that the separator is interposed between the positive electrode and the negative electrode. After the electrodes are stacked, the push plates are arranged at both ends of the stacked electrode groups to hold the electrode groups. Then, pressure is applied to both ends of the pressing plate to compress the electrode group, and the round bar is pulled out while maintaining the compressed state. Instead, the current collector is screwed into the electrode group, and the pressing plate is The current collector is screwed to assemble the electrode assembly while maintaining the compressed state of the electrode group. Then, the electrode assembly is press-fitted into the exterior body, air is evacuated, and an electrolytic solution is injected. (Claim 27).
According to this assembling method, the electrode assembly is press-fitted into an exterior body composed of a cylindrical can with a bottom, and after the electrolyte is injected, the cylindrical can is sealed with the lid member to seal the battery.

In the method for assembling the laminated battery according to the present invention, the separator is inserted into a round bar having the same outer diameter as that of the thread valley formed on the side surface of the current collector so that the separator is interposed between the positive electrode and the negative electrode. After stacking and compressing the electrodes, the round bar is pulled out while maintaining the compressed state, and the current collector is screwed in instead to assemble the electrode assembly. Then, the electrode assembly is press-fitted into the exterior body, air is evacuated, an electrolyte is injected, and then the electrode group is sealed inside the exterior body with a lid member that acts as a push plate. ).
According to this assembling method, the electrode assembly is press-fitted into the pipe-shaped exterior body, and then the exterior body opening is covered with the lid member to seal the laminated battery.

  In the manufacture of the electrode assembly according to the present invention, a method of reducing the irreversible capacity by doping the second electrode with an alkali metal by supplying a current to the electrolyte solution and causing the current to flow through the electrode assembly. It is effective (claim 29).

  The electrode assembly causes an irreversible capacity to be reduced by doping the second electrode with an alkali metal by causing a current to flow through the electrode assembly into which the current collector is screwed in a non-aqueous electrolyte. According to this method of reducing irreversible capacity, even if an electrode having irreversible capacity is used for the second electrode, the second electrode is doped with alkali metal, so that an electrode assembly with reduced irreversible capacity can be obtained. it can.

  The present invention makes it possible to provide a non-aqueous secondary battery that suppresses the temperature rise inside the battery and does not require extra space for cooling.

It is the schematic perspective view which fractured | ruptured some cylindrical winding batteries. It is a figure which shows typically the condition of the temperature gradient of a cylindrical winding battery. It is a schematic block diagram of the cylindrical laminated battery which concerns on Example 1 of this invention, and is a figure which shows an axial direction cross section. It is the figure which showed typically the screw structure of the electrical power collector, and is the elements on larger scale when an electrode group is inserted in the electrical power collector. It is drawing (a top view and a side view) of the collector of a longitudinal groove structure. It is a schematic axial sectional view showing a modification of the cylindrical laminated battery according to the first embodiment of the present invention shown in FIG. It is sectional drawing explaining the assembly method of a cylindrical laminated battery. (A) is an axial sectional view when an electrode group is incorporated in a round bar, and (b) is an axial sectional view when a current collector is screwed out by pulling out the round bar. It is a schematic block diagram of the square laminated battery which concerns on Example 2 of this invention. (A) is an axial sectional view, and (b) is a plan view. It is a block diagram when it is set as an assembled battery using the square laminated battery which concerns on Example 2 of this invention. It is a schematic block diagram of the cylindrical laminated battery which concerns on Example 3 of this invention, and is a figure which shows an axial direction cross section. It is a block diagram when it is set as an assembled battery using the cylindrical laminated battery which concerns on Example 3 of this invention. (A) is a schematic block diagram explaining the connection condition of a connection metal fitting and a laminated battery, (b) is a figure explaining the structure at the time of comprising an assembled battery. It is a schematic block diagram which shows the cylindrical laminated battery which concerns on Example 4 of this invention, and is a figure which shows an axial direction cross section. It is a block diagram when it is set as an assembled battery using the cylindrical laminated battery which concerns on Example 4 of this invention. (A) is a figure explaining the case where an assembled battery is comprised, (b) is a top view of the bracket for comprising an assembled battery. It is a schematic block diagram which shows the cylindrical laminated battery which concerns on Example 5 of this invention. (A) is an axial sectional view, and (b) is a plan view of a positive electrode, a negative electrode, and a separator. It is a block diagram when it is set as an assembled battery using the cylindrical laminated battery which concerns on Example 5 of this invention. (A) is a figure explaining the case where an assembled battery is comprised, (b) is a top view of the heat sink for comprising an assembled battery. It is a schematic block diagram which shows the modification of the cylindrical laminated battery which concerns on Example 5 of this invention. It is a schematic block diagram which shows the cylindrical laminated battery which concerns on Example 6 of this invention.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments. The electrode, electrolyte solution and separator used in the laminated battery of the present invention are not particularly limited as long as they are generally used in non-aqueous secondary batteries. Non-aqueous secondary batteries include lithium secondary batteries, sodium secondary batteries, magnesium secondary batteries, calcium secondary batteries, etc., and lithium ion capacitors, sodium ion capacitors, magnesium ion capacitors, and calcium ion capacitors are also non-aqueous. Included in secondary batteries.

  In the description of the embodiment of the present invention, a lithium secondary battery will be described for convenience of explanation, but any secondary battery using a non-aqueous electrolyte may be used, and the present invention is not limited to a lithium secondary battery.

Prior to describing each embodiment of the present invention, matters common to all the embodiments will be described. That is, among the above secondary batteries, a lithium secondary battery is preferable because of its high operating potential and high discharge capacity. Hereinafter, taking the lithium secondary battery as an example, the production of the electrode, such as the electrode, the electrolytic solution and the separator, will be described first, and then the production of other main components of the lithium secondary battery will be described.
<Manufacture of electrodes and main components>

The negative electrode was prepared by mixing lithium titanate, CMC, and ketjen black (KB) (mass ratio of 90: 5: 5) to prepare a slurry mixture. This mixture was applied onto a 20 μm-thick stainless steel foil, temporarily dried, and then heat-treated (in a reduced pressure, at 160 ° C. for 5 hours or more) to obtain a negative electrode.
Ketjen black is a group of carbon fine particles having a diameter of about 3 to 500 nm, and is mainly used as a conductive agent that improves the conductivity of the electrode.

  The negative electrode contains a negative electrode active material capable of occluding and releasing lithium and a binder. Here, the negative electrode active material capable of occluding and releasing lithium is capable of occluding lithium ions during initial charging, and occluding and releasing lithium ions during subsequent charging and discharging. If there is, it is not limited to the above. From the standpoint of material costs and the difficulty of generating lithium dendrites due to low temperature charging and high speed charging, hard carbon, soft carbon, tin phosphate, silicon, silicon monoxide, tin, tin monoxide, tin dioxide, It may be tin oxalate, tin-copper alloy, or the like.

  Soft carbon, also called graphitizable carbon, is a carbon material that tends to have a graphite structure when heat-treated in an inert atmosphere. Hard carbon, also called non-graphitizable carbon, has developed a graphite structure. A carbon material having a suppressed and irregular structure, and both carbons are mainly used as a negative electrode active material of a lithium secondary battery.

  The positive electrode was prepared by mixing lithium iron phosphate, CMC, activated carbon, and KB (89: 4: 2: 5 by mass ratio) to prepare a slurry mixture. This mixture was applied onto a stainless steel foil having a thickness of 20 μm, temporarily dried, and then heat-treated (during decompression, 160 ° C., 5 hours or more) to obtain a positive electrode.

  The positive electrode contains a positive electrode active material capable of inserting and extracting lithium and a binder. Here, the positive electrode active material capable of occluding and releasing lithium is capable of occluding lithium ions in the initial charge, and occluding and releasing lithium ions during subsequent charging and discharging. If there is, it is not limited to the above. From the viewpoint of the redox potential and the amount capable of occlusion and release of lithium ions, for example, lithium cobaltate, lithium nickelate, lithium cobalt manganese nickelate, lithium manganate, lithium iron phosphate, vanadium oxide-based materials, sulfur-based Examples include materials and existing materials such as graphite. From the viewpoint of material cost and high-temperature durability, the positive electrode active material is preferably lithium iron phosphate.

  A polypropylene microporous membrane was used as a separator. The separator is not limited to polypropylene as long as it is a material that transmits lithium ions but does not transmit electrons. For example, a porous sheet made of a resin such as polyethylene, polyester, cellulose, aramid, or polyamide, a glass filter, a nonwoven fabric, or a woven fabric can be used as a material for forming the separator.

As the electrolytic solution, 1 mol / L LiPF ₆ / EC: DEC (50:50 vol%) was employed. The electrolyte solution may be a non-aqueous electrolyte that is generally used in lithium secondary batteries. Since the electrolyte used in the electrolyte solution needs to contain lithium ions, the electrolyte salt is not limited to the above as long as it is used in a lithium secondary battery, but a lithium salt is preferable as the electrolyte salt. is there. As the lithium salt, for example, at least one selected from the group consisting of lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium trifluoromethanesulfonate, and lithium trifluoromethanesulfonate imide may be used. it can. Since the lithium salt has a high electronegative property and is easily ionized, it has excellent charge / discharge cycle characteristics and can improve the charge / discharge capacity of the secondary battery.

  Examples of the solvent for the electrolyte include propylene carbonate (PC), ethylene carbonate (EC), dimethyl carbonate (DMC), diethyl carbonate (DEC), γ-butyrolactone, 2-methyltetrahydrofuran, 1,3-dioxolane, 4- At least selected from the group consisting of methyl-1,3-dioxolane, 1,2-dimethoxyethane, 1,2-diethoxyethane, diethyl ether, sulfolane, methyl sulfolane, nitromethane, N, N-dimethylformamide, dimethyl sulfoxide One kind can be used, and propylene carbonate alone, a mixture of ethylene carbonate and diethyl carbonate, or γ-butyrolactone alone is particularly suitable.

  The mixing ratio of the mixture of ethylene carbonate and diethyl carbonate can be arbitrarily adjusted in the range of 10 to 90 vol% for both ethylene carbonate and diethyl carbonate. Alternatively, a solid electrolyte may be used without using a solvent.

  As a method for producing a negative electrode, for example, a powder obtained by adding a negative electrode active material, a binder, and, if necessary, a conductive agent to a paste by adding a solvent or water is applied and molded on a current collector. Can be manufactured. Similarly, as a method for producing the positive electrode, a powder obtained by adding a positive electrode active material, a binder, and, if necessary, a conductive agent to a paste by adding a solvent or water is applied and molded on a current collector. Can be used.

  Ketjen black (KB) was used as the conductive agent, but there is no particular limitation as long as it is a conductive powder, but a carbon material having low material cost and high conductivity is preferable. For example, carbon materials such as acetylene black (AB), graphite, carbon fiber, carbon tube, and amorphous carbon may be used singly or in combination of two or more.

As the binder, carboxymethyl cellulose (CMC) was used. For example, polyvinylidene fluoride, polytetrafluoroethylene, polyimide, polyamide, polyamideimide, polyacryl, styrene butadiene rubber, styrene-ethylene-butylene-styrene copolymer, carboxymethyl cellulose, etc. may be used alone, Two or more kinds may be used in combination. From the viewpoint of high temperature durability, the binder is preferably polyimide, polyamide, polyamideimide, polyacryl, carboxymethylcellulose, or the like. Among these, carboxymethyl cellulose is more preferable because water can be used as a solvent.
As the current collector, stainless steel is used. However, the current collector is not limited to this as long as the material has electron conductivity and can conduct electricity to the held negative electrode material.

  For example, conductive materials such as C, Ti, Cr, Ni, Au, and Al, alloys containing two or more of these conductive materials (for example, stainless steel), conductive glass and polymers, etc. are used. Can do. In the case where the second electrode is a negative electrode, the current collector is preferably made of a material having high electrical conductivity and good stability in the electrolytic solution and not easily alloyed with lithium. Specifically, C, Ti, Cr, Ni, Cu, Au, stainless steel, and the like are preferable, and C, Ni, Cu, stainless steel, and the like are more preferable from the viewpoint of material cost.

  When the second electrode is a positive electrode, the current collector is preferably made of a material that has high electrical conductivity and is not easily alloyed with lithium and stability in the electrolyte, and specifically, C, Al, stainless steel, etc. are preferred. . The shape of the current collector is a rod, but in addition, there are linear, plate-like, foil-like, net-like, woven fabric, non-woven fabric, expand, porous body or foam, among which the packing density can be increased. Expandable, porous or foamed materials are preferred because they can be produced and output characteristics are good.

  The outer package may be a can, preferably iron (Fe), copper (Cu), nickel (Ni), aluminum (Al), titanium (Ti), chromium (Cr), gold (Au), stainless steel. Any metal can be used. Furthermore, although conductive glass, carbon (C), a polymer, etc. may be sufficient, iron, copper, nickel, aluminum, gold | metal | money, stainless steel etc. are preferable from a viewpoint of heat conductivity and electronic conductivity. In addition, when a 1st electrode is a positive electrode, although it changes with active materials to be used, an aluminum, stainless steel, etc. are preferable from a viewpoint of oxidation resistance. When the first electrode is a negative electrode, copper, nickel, stainless steel, and the like are preferable from the viewpoint of reduction resistance, although depending on the active material used. In this embodiment, stainless steel is used for both.

  In the laminated battery according to the present invention, the current collector and the second electrode are joined by an adhesive. Even if the diameter of the hole provided in the second electrode is larger than the outer diameter of the screw valley of the current collector, for example, by joining the current collector and the second electrode with a conductive adhesive. This is because it is possible to ensure electrical contact between the second electrode and the current collector. Furthermore, by joining the current collector and the second electrode with an adhesive, it is possible to reliably prevent the electrode from falling out of the current collector during assembly processing.

  And preferably, the adhesive is composed of a resin that does not dissolve in the electrolytic solution and carbon powder, and when the mixing ratio is 100% by mass, the resin that does not dissolve in the electrolytic solution is 30 to 90% by mass, When the carbon powder is 10 to 70% by mass, the reason why the resin that does not dissolve in the electrolytic solution is limited to 30 to 90% by mass is that the carbon powder is bulky if it is less than 30% by mass, and sufficient adhesion is achieved. This is because it is difficult to ensure sufficient conductivity, and when it exceeds 90% by mass, it is difficult to ensure sufficient conductivity even if carbon powder is mixed. Therefore, the resin that does not dissolve in the electrolytic solution is preferably 30 to 90% by mass, and more preferably 50 to 70% by mass. Similarly, it is preferable that carbon powder is 10-70 mass%, and it is more preferable that it is 30-50 mass%.

  In addition, polyimide was adopted as a resin that does not dissolve in the electrolytic solution. Resins that do not dissolve in the electrolyte include polyvinylidene fluoride (PVdF), polyvinyl alcohol (PVA), ethylene vinyl alcohol (EVA), polytetrafluoroethylene, polyimide (PI), polyamide, polyamideimide, polyacryl, styrene butadiene rubber (SBR), styrene-ethylene-butylene-styrene copolymer (SEBS), carboxymethylcellulose (CMC), polyacryl, and the like. Among these, CMC, PVA, polyacryl, polyimide, polyamide, and polyamideimide are preferable from the viewpoint of being stable in the electrolytic solution and adhesiveness. Of these, polyimide is more preferable from the viewpoint of heat resistance.

  FIG. 3 is a schematic cross-sectional view in the axial direction of the cylindrical laminated battery according to the embodiment of the present invention. A cylindrical laminated battery 11 (hereinafter simply referred to as a laminated battery) shown in FIG. 3 includes an exterior body 15, a current collector 17, and an electrode body 13 housed inside the exterior body as main components. The exterior body 15 includes a bottomed cylindrical can 12 and a disk-shaped lid member 16 attached to the opening 12 c of the cylindrical can 12. The cylindrical can 12 and the lid member 16 are made of stainless steel, but may be other metals. The outer diameter of the lid member 16 is slightly larger than the inner diameter of the opening 12 c of the cylindrical can 12, and the lid member 16 is tightly fitted in the cylindrical can opening 12 c after the electrode body 13 is stored.

  The electrode body 13 includes a positive electrode 13a including a positive electrode active material, a negative electrode 13b including a negative electrode active material, and a separator 13c that is interposed between the positive electrode 13a and the negative electrode 13b and transmits ions but does not transmit electrons. The cylindrical can 12 is stacked in the axial direction (X direction in FIG. 3) and stored in the exterior body 15. In addition, the electrolyte solution (not shown) is hold | maintained at the separator 13c. Each of the positive electrode 13a, the negative electrode 13b, and the separator 13c has a disk shape with a hole in the center. The outer diameter 13ab of the positive electrode 13a is smaller than the inner diameter 12a of the cylindrical can 12, and the positive electrode 13a and the cylindrical can 12 is not in contact. On the other hand, the outer diameter 13bb of the negative electrode 13b is larger than the inner diameter 12a of the cylindrical can 12, the outer periphery 13bb of the negative electrode is in contact with the inner surface 12a of the cylindrical can 12, and the negative electrode 13b and the cylindrical can 12 are electrically connected. Preferably, the outer diameter 13bb of the negative electrode 13b is 100 μm larger than the inner diameter 12a of the cylindrical can 12.

  The current collector 17 is made of stainless steel, and has a rod-shaped shaft portion 17a and a stopper portion 17b disposed at one end of the shaft portion 17a. The shaft portion 17a of the current collector 17 passes through the center of the electrode body 13 including the positive electrode 13a, the negative electrode 13b, and the separator 13c in the axial direction of the exterior body 15 (X direction in FIG. 3). The diameter of the hole 13aa provided in the center of the positive electrode 13a is smaller than the outer diameter of the shaft portion 17a, and the positive electrode 13a is in contact with and electrically connected to the shaft portion 17a. On the other hand, the diameter of the hole 13ba provided at the center of the negative electrode 13b is larger than the outer diameter of the shaft portion 17a, and the negative electrode 13b is not in contact with the shaft portion 17a and is electrically insulated.

  The side surface of the current collector 17 is threaded to form a screw portion 17c. Specifically, the current collector 17 has a screw structure in which a trough diameter is d and a crest diameter is D (d <D) as schematically shown in FIG. . The specification of the screw is the M screw referred to in JIS, but may be the ISO specification.

  FIG. 4 is a cross-sectional view schematically showing the relationship between the current collector 17 and the electrode 13. As shown in this figure, the diameter of the hole 13aa provided in the positive electrode 13 is smaller than the diameter (d) of the valley of the screw portion 17c, and the positive electrode 13a is screwed into contact with the shaft portion 17a. On the other hand, the diameter of the hole 13ba provided in the negative electrode 13b is larger than the diameter (D) of the crest of the screw portion 17c, and the negative electrode 13b is not in contact with the shaft portion 17a.

  In this embodiment, the current collector 17 uses M4 bolts, and the peak diameter (D) is 4.0 mm and the valley diameter (d) is 3.7 mm. The diameters 13aa and 13ca of the positive and separator holes are 3.5 mm.

  FIG. 5 shows a plan view and a side view of a current collector 17 ′ according to another embodiment. A V-shaped groove is provided in the axial direction over the entire circumference of the side surface of the current collector 17 ′, and the cross section thereof has a sawtooth shape. The serrated tip may be somewhat rounded. If the cross section of the current collector is sawtooth-shaped, the contact surface with the electrode is large, and even if it is consolidated in the longitudinal direction, the electrode slides along the groove and hardly causes contact failure. In general, a secondary battery expands and contracts in the process of repeated charge and discharge, and even if the electrode is deformed in the charge and discharge process, the electrode slides along the groove so that the electrode is not damaged.

The electrode body 13 is disposed so as to be sequentially stacked on the current collector stop portion 17 b, and the stop portion 17 b prevents the electrode body 13 from falling off the end of the current collector 17. The shape of the stop portion 17b is a disk shape. The stopper portion 17b is disposed on the cylindrical can bottom portion 12b, but an insulating plate 14 is disposed between the cylindrical can bottom portion 12b and the stopper portion 17b so that the current collector 17 and the cylindrical can 12 are in contact with each other. This prevents an electrical short circuit. The end of the shaft portion 17a opposite to the stop portion 17b is supported by a bearing 18 provided at the center of the lid member 16. In order to prevent an electrical short circuit between the lid member 16 and the shaft portion 17a, the bearing 18 is made of an insulating material.
A shaft portion penetrating the lid member 16 constitutes a positive electrode terminal 17d. The cylindrical can 12 functions as a negative electrode terminal.
Next, operations and effects of the first embodiment will be described.
<About cooling structure>

  Since the outer diameter 13bb of the negative electrode 13b is larger than the inner diameter 12a of the cylindrical can 12, the negative electrode 13b is strongly pressed against the cylindrical can 12 and is in close contact therewith. The heat generated in the negative electrode 13 b is directly transmitted to the cylindrical can 12. The heat generated in the positive electrode 13a is transferred to the negative electrode 13b through the separator 13c. Although the separator 13c is difficult to transfer heat, it is thin (10 μm in this embodiment) and only one sheet does not hinder heat conduction. As described above, the heat generated in the electrodes 13a and 13b is transmitted to the cylindrical can 12 with a small thermal gradient, and it is possible to suppress the temperature rise inside the laminated battery.

In this way, since the temperature rise at the center of the laminated battery can be reduced, there is no need to provide a pipe or the like for flowing a refrigerant inside the battery, and thus the temperature rise can be suppressed with a compact structure. Furthermore, since the exterior body 12 is exposed to the outside, it can be cooled relatively easily, and the temperature rise can be effectively suppressed as compared with the conventional wound battery. Here, the difference in temperature rise between the laminated battery according to the embodiment of the present invention and the conventional wound battery is shown as a calculation example.
The overall heat transfer coefficient (U ₁ ) of the wound battery is expressed by Equation 3, and the overall heat transfer coefficient (U ₂ ) of the laminated battery according to the present invention is expressed by Equation 4.

ここで、１８６５０型電池を例に取り計算してみる。捲回電池の諸元は、

Here, calculation will be made taking an 18650 type battery as an example. The specifications of the wound battery

_{t = 0.5mm, t + = t} - = t s = 10μm, k = k + = k - = 40Wm -2 deg -1
h ₀ = 100 Wm ^-2 deg ^-1 , h ₁ = 1 Wm ^-2 deg ^-1 , k _s = 1 Wm ^-2 deg ^-1 , n = 9 / 0.03 = 300
By substituting these values into Equation 3, U ₁ = 0.0011 Wm ⁻² deg ⁻¹ is obtained.
On the other hand, the specifications of the laminated battery according to this embodiment are as follows:

h ₀ = 100 Wm ^-2 deg ^-1 , t = 0.5mm, k = 40Wm ^-2 deg ^-1
h ₁ = 10000 Wm ^-2 deg ^-1 , t ^* = 0.009m, k ^* = 40Wm ^-2 deg ^-1
Therefore, by substituting these values into Equation 4, U ₂ = 100 Wm ⁻² deg ⁻¹ is obtained.
Comparing the two, it can be said that the cooling structure according to the present invention is excellent in heat transfer nearly 100,000 times as compared with the conventional wound battery.
<Modification of First Embodiment>

  FIG. 6 shows a modification of the laminated battery according to Example 1 of the present invention. The cylindrical laminated battery 90 is configured by accommodating the electrode assembly B inside a cylindrical can 92. As shown in FIG. 7B, the electrode assembly B mainly includes a rod-shaped current collector 97 made of a conductive material obtained by applying nickel plating to iron, and an electrode body 93. Then, a threaded portion 97c having a threaded groove is provided on the outer periphery of the side of the current collector 97. The current collector 97 passes through the center of the electrode body 93 including the positive electrode 93a, the negative electrode 93b, and the separator 93c. The diameter of the hole 93ba provided at the center of the negative electrode 93b is smaller than the diameter (d) of the valley of the screw portion 97c, and the negative electrode 93b is in contact with the current collector 97. On the other hand, the diameter of the hole 93aa provided in the positive electrode 93a is larger than the diameter (D) of the crest of the screw portion 97c, and the positive electrode 93a is not in contact with the current collector 97. Specifically, the current collector 97 uses M4 bolts, and the diameter (D) of the peak is 4.0 mm and the diameter (d) of the valley is 3.7 mm. The diameters 93aa and 93ca of the positive and separator holes are 3.5 mm.

  The electrode bodies 93 are arranged so as to be sequentially stacked on a push plate 98b positioned below the current collector 97, and the push plate 98b prevents the electrode body 93 from dropping off from the end of the current collector 97. Yes. The pressing plate 98b is made of disc-shaped stainless steel. A push plate 98a is disposed on the uppermost portion of the stacked electrode bodies 93, and the electrode bodies 93 can be compressed by the push plates 98a and 98b.

  The electrode assembly B is inserted in the axial direction of the cylindrical can 92 (X direction in FIG. 6). The outer diameter 93bb of the negative electrode 93b is smaller than the inner diameter 92a of the cylindrical can 92, and the negative electrode 93b and the cylindrical can 92 are not in contact with each other. On the other hand, the outer diameter 93ab of the positive electrode 93a is larger than the inner diameter 92a of the cylindrical can 92, the outer periphery 93ab of the positive electrode is in contact with the inner surface 92a of the cylindrical can 92, and the positive electrode 93a and the cylindrical can 92 are electrically connected. The upper opening of the cylindrical can 92 is covered with a lid member 96 so that the electrode assembly B can be sealed inside the cylindrical can 92. An insulating material 99 is disposed between the lid member 96 and the cylindrical can 92 to prevent the lid member 96 and the cylindrical can 92 from contacting and electrically short-circuiting.

An insulating sheet 94 is disposed on the cylindrical can bottom portion 92b, and the current collector end portion 97b is in direct contact with the cylindrical can bottom portion 92b to prevent the current collector 17 and the cylindrical can 12 from being electrically short-circuited. ing. A connecting plate 91 made of a plate-like elastic body that protrudes downward is attached to the other end 97a of the current collector. The end portion 91 a of the connection plate is in contact with the bottom surface 96 b of the lid member and is urged downward by the lid member 96. As a result, the current collector 97 and the lid member 96 are electrically connected via the connection plate 91.
The protrusion 96a provided at the center of the lid member 96 functions as a negative electrode terminal. The cylindrical can 92 functions as a positive electrode terminal.

  Next, a method for assembling the laminated battery according to the present invention will be described with reference to FIG. Sequentially inserted into a round bar 95 having an outer diameter of 3.5 mm smaller than the diameter (d) of the thread valley formed on the side surface of the current collector 97 so that the separator 93c is interposed between the positive electrode 93a and the negative electrode 93b. Then, after the electrode bodies 93a, b, c are stacked, the push plates 98a, 98b are arranged on both ends of the stacked electrode groups to hold the electrode groups, and the electrode current collector A is assembled. Then, the electrode group is compressed via the push plates 98a and 98b, and the round bar 95 is pulled out while maintaining the compressed state. Instead, the current collector 97 is pressed against the electrode group held by the push plates 98a and 98b. Screw in by rotating while applying. At this time, since the push plates 98a and 98b are screwed to the current collector 97, it is possible to assemble the electrode assembly B while maintaining the compressed state of the electrode group. Then, the electrode assembly B is press-fitted into the cylindrical can 92, air is evacuated, and an electrolytic solution is injected. After injection of the electrolytic solution, a lid member 96 is attached to the opening of the cylindrical can 92, and the opening of the cylindrical can 92 is crimped to seal the laminated battery.

  FIG. 8 shows a cylindrical laminated battery according to Example 2 of the present invention. As shown in the plan view of FIG. 8B, the battery as a whole has a square shape. A rectangular laminated battery 71 shown in FIG. 8A includes an outer package 75 including a body member 72 and a lid member 73, a positive electrode 74a including a positive electrode active material, a negative electrode 74b including a negative electrode active material, and positive and negative electrodes 74a and 74b. It has an electrode body 74 made up of a separator 74c, which is interposed between them and transmits ions but does not transmit electrons, as a main component. The body member 72 is a bottomed rectangular container, and the opening 72c is covered with a lid member 73 so that a sealed space can be formed inside the body member 72. The body member 72 and the lid member 73 are made of stainless steel, but may be other metals.

  The positive electrode 74a and the negative electrode 74b are stacked in the axial direction of the body member 72 (Y direction in FIG. 8) via the separator 74c and housed in the exterior body 75. Note that an electrolytic solution (not shown) is held in the separator 74c. The positive electrode 74a, the negative electrode 74b, and the separator 74c are all sheet-like. The outer dimension 74bb of the negative electrode 74b is smaller than the inner dimension 72a of the trunk member 72, and the negative electrode 74b and the trunk member 72 are not in contact with each other. On the other hand, the outer dimension 74ab of the positive electrode 74a is larger than the inner dimension 72a of the barrel member 72, the outer periphery 74ab of the positive electrode 74a is in contact with the inner surface 72a of the barrel member 72 with pressure, and the positive electrode 74a is electrically connected to the barrel member 72. It is connected to the. Therefore, since the heat generated in the electrode body 74 is directly transmitted to the body member 72 with a small thermal gradient, the temperature rise of the electrode body 74 is suppressed. Preferably, the outer dimension 74 ab of the positive electrode 74 a is 100 μm larger than the inner dimension 72 a of the body member 72.

  The current collector 77 is made of stainless steel, and has a dish portion 77b having an inverted conical shape and a shaft portion 77a following the plate portion 77b. The side surface of the shaft portion 77a is threaded to form a screw portion 77c, and the current collector 77 constitutes a countersunk screw as a whole.

The electrode body 74 composed of the positive electrode 74a, the negative electrode 74b, and the separator 74c is provided with holes 74aa, 74ba, and 74ca, and the shaft portion 77a of the current collector 77 connects the electrode body 74 in the axial direction of the exterior body 75 ( It penetrates in the Y direction of FIG. The diameter of the hole 74ba provided in the negative electrode 74b is smaller than the outer diameter of the shaft portion 77a, and the negative electrode 74b is in contact with and electrically connected to the shaft portion 77a. On the other hand, the diameter of the hole 74aa provided in the positive electrode 74a is larger than the outer diameter of the shaft portion 77a, and the positive electrode 74a is electrically insulated without contacting the shaft portion 77a.

  The four current collectors 77 (see FIG. 8B) are connected to each other by a connecting plate 77d provided below the electrode body 74. That is, the current collector 77 and the connection plate 77d are connected by screwing the screw portion 77c into the screw hole 77da provided in the connection plate 77d at the lower end 77ca of the current collector. The electrode bodies 74 are arranged so as to be sequentially stacked on the connection plate 77 d, and the connection plate 77 d prevents the electrode body 74 from dropping from the end of the current collector 77. An insulating plate 76b is disposed between the trunk member bottom portion 72b and the connecting plate 77d. The connecting plate 77d comes into contact with the trunk member bottom portion 72b, and the current collector 77 and the trunk member 72 are electrically short-circuited. Is preventing. Specifically, the connecting plate 77d is surrounded by an insulating plate 76b made of polypropylene.

  The lid member 73 has a flat plate portion 73a and a bent portion 73b that bends at a right angle from the flat plate portion. An insulating plate 76a is disposed inside the bent portion 73b and in the opening 72c of the trunk member, and the uppermost electrode body 74 contacts the lid member 73 and is electrically short-circuited. Is preventing. A groove 76aa into which the outer edge of the opening of the body member 72 is fitted is provided on the surface of the insulating plate 76a opposite to the lid member 73. A sealing material 176 made of polyimide is disposed between the groove 76aa and the outer edge of the opening of the body member 72 to keep the inside of the exterior body 75 airtight. For the same purpose, a sealing material 176 made of polyimide is also disposed in a hole through which the current collector shaft portion 77a of the insulating plate 76a passes.

The lid member 73 is connected to the connecting plate 77 d by a current collector 77 that acts as a countersunk screw, and is fixed to the body member 72 via the electrode body 74. The body member 72 functions as a positive electrode terminal, and the lid member 73 functions as a negative electrode terminal.
<Battery assembly>

  FIG. 9 shows a schematic configuration diagram when the assembled battery 70 is configured using the prismatic stacked battery 71. A plurality of prismatic laminated batteries are connected in series by laminating the flat plate portion 73a of the lid member of the prismatic laminated battery 71 and the bottom portion 72b of the trunk member of the adjacent prismatic laminated battery in the facing direction. The series-connected prismatic laminated batteries are sandwiched between a positive terminal plate 78a and a negative terminal plate 78b. That is, the assembled battery 70 is configured by arranging a positive terminal plate 78 a that contacts the body member 72 and a negative terminal plate 78 b that contacts the lid member 73 and housed in the housing 70 a. The assembled battery 70 is cooled by supplying cooling air from the outside to the inside 70 a by the suction fan 79 a and the pushing fan 79 b. The output of the assembled battery is taken out from the positive terminal 78ab and the negative terminal 78bb.

  FIG. 10 is a schematic sectional view in the axial direction of a pipe laminated battery (hereinafter simply referred to as a laminated battery) according to Example 3 of the present invention. The laminated battery 21 shown in FIG. 10 includes an exterior body 25, a current collector 27, and an electrode body 23 housed in the exterior body as main components. The exterior body 25 includes a circular tube 22 and a disk-shaped lid member 26 attached to the opening portions 22b at both ends of the circular tube 22. The circular tube 22 and the lid member 26 are made of stainless steel, but may be other metals. The outer diameter of the lid member 26 is slightly larger than the inner diameter of the opening 22 b of the circular tube 22, and the lid member 26 is tightly fitted in the circular tube opening 22 b after the electrode body 23 is stored.

  The electrode body 23 includes a positive electrode 23a including a positive electrode active material, a negative electrode 23b including a negative electrode active material, and a separator 23c interposed between the positive electrode 23a and the negative electrode 23b to transmit ions but not transmit electrons. The tubes 22 are stacked in the axial direction of the circular tube 22 (X direction in FIG. 10) and housed in the exterior body 25. In addition, the electrolyte solution (not shown) is hold | maintained at the separator 23c. Each of the positive electrode 23a, the negative electrode 23b, and the separator 23c has a disk shape with a hole in the center. The outer diameter 23bb of the negative electrode 23b is smaller than the inner diameter 22a of the circular tube 22, and the negative electrode 23b is a circular tube. 22 is not touching. On the other hand, the outer diameter 23ab of the positive electrode 23a is larger than the inner diameter 22a of the circular tube 22, and the positive electrode 23a is in contact with the inner surface 22a of the circular tube 22 and is electrically connected to the circular tube 22. Preferably, the outer diameter 23ab of the positive electrode 23a is 100 μm larger than the inner diameter 22a of the circular tube 22.

  The current collector 27 is made of stainless steel, and has a shaft portion 27a at a central portion and end portions 27b at both end portions. The shaft portion 27a of the current collector 27 penetrates the center of the electrode body 23 composed of the positive electrode 23a, the negative electrode 23b, and the separator 23c in the axial direction of the exterior body 25 (X direction in FIG. 10). The diameter of the hole 23ba provided at the center of the negative electrode 23b is smaller than the outer diameter of the shaft portion 27a, and the negative electrode 23b is in contact with and electrically connected to the shaft portion 27a. On the other hand, the diameter of the hole 23aa provided in the center of the positive electrode 23a is larger than the outer diameter of the shaft portion 27a, and the positive electrode 23a is electrically insulated without contacting the shaft portion 27a. Further, the side surface of the current collector 27 is threaded to form a threaded portion 27c.

The electrode bodies 23 are sequentially stacked in a skewered state on the shaft portion 27a of the current collector. The current collector 27 is supported at both end portions 27b by a bearing 28 provided at the center of the lid member 26. In order to prevent an electrical short circuit between the lid member 26 and the current collector 27, the bearing 28 is made of an insulating material.
The current collector end portion 27b penetrating the lid member 26 becomes a negative electrode terminal 27c. The circular tube 22 functions as a positive electrode terminal.

  Next, a method for assembling the laminated battery according to the present invention will be described. The electrodes are inserted by sequentially inserting the separator 23c between the positive electrode 23a and the negative electrode 23b in a round bar (not shown) having the same outer diameter (d) as the screw valley formed on the side surface of the current collector 27. After stacking and compressing, the round bar is pulled out while maintaining the compressed state, and the current collector 23 is screwed in instead to assemble the electrode assembly. Then, the electrode assembly is press-fitted into the circular tube 22, air is evacuated, the electrolyte is injected, and then the electrode group 23 is sealed inside the circular tube 22 with a lid member that acts as a push plate. According to this assembling method, after the electrode assembly is press-fitted into the tubular outer package, the laminated battery can be sealed by covering the circular tube opening with the lid member 26.

  In FIG. 11A, the connection fitting 29 is shown together with the laminated battery 21. The connection fitting 29 is arranged in contact with the lid member 26 between the laminated battery 21 and the adjacent laminated battery 21 ′. The connection fitting 29 is made of columnar metal, and its axial direction coincides with the axial direction of the current collector 27 (X direction in FIG. 11). A hole 29aa perpendicular to the upper surface 29a is provided at the center of the upper surface 29a (the left surface in the figure) of the connection fitting 29 so that the current collector 27 ′ of the adjacent stacked battery 21 ′ can be fitted. ing. A hole 29ba perpendicular to the bottom surface 29b is provided at the center of the bottom surface 29b (right side surface in the figure) of the connection fitting 29 so that the insulating member 24 can be fitted therein. A hole 24a is provided in the center of the insulating member 24 in the vertical direction so that the current collector shaft portion 27a of the laminated battery 21 can be fitted. When the bottom surface 29 b of the connection fitting is in contact with the lid member 26 of the stacked battery, the stacked battery 21 and the adjacent stacked battery 21 ′ are electrically connected via the connection fitting 29. At this time, the insulating member 24 prevents the current collector 27 and the exterior body 25 from coming into contact with each other and causing an electrical short circuit.

As shown in FIG. 11 (b), by connecting the stacked batteries 21 adjacent to each other using the connection fitting 29, the stacked batteries can be connected in series to form the assembled battery 20.
Of the operational effects of the present embodiment, refer to the section of Embodiment 1 for matters relating to the cooling structure.

  FIG. 12 is a schematic cross-sectional view in the axial direction of a pipe laminated battery (hereinafter referred to as a laminated battery) according to Example 4 of the invention. A laminated battery 61 shown in FIG. 12 includes an exterior body 65, a current collector 67, and an electrode body 63 housed inside the exterior body as main components. The exterior body 65 includes a circular tube 62 and a disk-shaped lid member 66 attached to the openings 62c at both ends of the circular tube 62, and a sealed space for housing the electrode body 63 therein. Is forming. The circular tube 62 that becomes the body portion of the exterior body is made of stainless steel. The lid member 66 is composed of a first lid member 66a (right side in the figure) and a second lid member 66b, both of which are made of polypropylene, but may be other insulating resins. The outer diameters of the lid members 66 a and 66 b are both made slightly larger than the inner diameter of the opening 62 c of the circular tube 62, and a sealing material 68 is applied to the outer periphery of the lid member 66 so that the interior of the exterior body 65 is covered. Plays an airtight role. Polyimide is used as the sealing material 68, but other materials may be used as long as they have a sealing property. The current collector 67 has a rod-shaped shaft portion 67a at the center and a disk-shaped stopper portion 67b provided at one end of the shaft portion 67a. The current collector 67 is made of stainless steel.

  The electrode body 63 includes a positive electrode 63a including a positive electrode active material, a negative electrode 63b including a negative electrode active material, and a separator 63c that is interposed between the positive electrode 63a and the negative electrode 63b and transmits ions but does not transmit electrons. The tubes 62 are stacked in the axial direction of the circular tube 62 (X direction in FIG. 12) and housed in the exterior body 65. The electrolyte solution (not shown) is held by the separator 63c. Each of the positive electrode 63a, the negative electrode 63b, and the separator 63c has a disk shape with a hole in the center. The outer diameter 63ab of the positive electrode 63a is smaller than the inner diameter 62a of the circular tube 62. 62 is not in contact. On the other hand, the outer diameter 63bb of the negative electrode 63b is larger than the inner diameter 62a of the circular tube 62, and the negative electrode 63b is in contact with the inner surface 62a of the circular tube 62 and is electrically connected to the circular tube 62. Preferably, the outer diameter 63bb of the negative electrode 63b is 100 μm larger than the inner diameter 62a of the circular tube 62.

  The shaft portion 67a of the current collector 67 passes through the center of the electrode body 63 composed of the positive electrode 63a, the negative electrode 63b, and the separator 63c in the axial direction of the exterior body 25 (X direction in FIG. 12). The diameter of the hole 63aa provided at the center of the positive electrode 63a is smaller than the outer diameter of the shaft portion 67a, and the positive electrode 63a is in contact with and electrically connected to the shaft portion 67a. On the other hand, the diameter of the hole 63ba provided in the center of the negative electrode 63b is larger than the outer diameter of the shaft portion 67a, and the negative electrode 63b is electrically insulated without contacting the shaft portion 67a. Note that the collector stop portion 67b is covered with polypropylene and housed inside the second lid member 66b. Further, a thread groove is formed on the side surface of the current collector 67a to form a threaded portion 67c.

Next, a method for assembling the laminated battery 61 will be described. The electrode body 63 is sequentially inserted into the shaft portion 67a of the current collector so that the separator 63c is interposed between the positive electrode 63a and the negative electrode 63b with the second lid member 66b housing the current collector stop portion 67b facing down. And then go on to stack. The stopper portion 67 b makes it possible to prevent the electrode body 63 from falling off the current collector 67. The assembled electrode assembly is compressed in the axial direction (X direction in FIG. 12) using a vise, and is pressed into the circular tube 62 while maintaining the compressed state. Thereafter, the air inside the exterior body 65 is removed using a vacuum pump, an electrolytic solution (not shown) is injected into the exterior body 65, and the first lid member 66a is attached. And the 1st cover member 66a is fixed by screwing together the nut 64, and the movement to the outward (right direction of a figure) is restrict | limited. The lid members 66a and 66b are pressure-bonded to the circular tube 62 by fitting the circular tube opening 62c after press-fitting the electrode body 63 into the exterior body 65.
The end of the current collector passing through the first lid member 66a constitutes a positive electrode terminal 67d. The circular tube 62 functions as a negative electrode terminal.

The assembled battery 60 may be configured by connecting the stacked batteries 61 using a bracket 69 shown in FIG. 13B made of a metal plate having two large and small holes (see FIG. 13A). The bracket 69 is provided with a hole 69a for fitting the circular tube 62 of the laminated battery and a hole 69b for fitting the positive electrode terminal 67d. A circular tube 62 of the laminated battery is attached to the hole 69a of the bracket. The positive electrode terminal 67d is attached to the bracket 69 by inserting the positive electrode terminal 67d of the adjacent laminated battery into the other hole 69b of the bracket and screwing the nut 64a. In this way, a plurality of stacked batteries are connected in series via the bracket 69. The bracket 69 serves to electrically connect adjacent stacked batteries 61 and further functions as a heat sink for the stacked batteries. The cooling capacity can be increased by sending cooling air in a direction parallel to the bracket by the fan 69c. It is possible to increase the output voltage by connecting the stacked batteries one after another using a plurality of brackets to increase the number of stacked batteries in series.
Of the operational effects of the present embodiment, refer to the section of Embodiment 1 for matters relating to the cooling structure.

  FIG. 14 is a schematic cross-sectional view in the axial direction of a cylindrical laminated battery (hereinafter simply referred to as a laminated battery) according to Example 5 of the invention. A laminated battery 41 shown in FIG. 14 includes two batteries 41-1 and 41-2 each having an outer body 45, a current collector 47, and an electrode body 43 housed in the outer body as main components. It is the battery formed by connecting via the connection piece 44 which consists of.

  In the first battery 41-1 and the second battery 41-2, the exterior bodies 45-1 and 45-2 are made of a bottomed cylinder made of stainless steel. A metal other than stainless steel may be used as long as it has conductivity.

  The electrode bodies 43-1 and 43-2 include positive electrodes 43-1a and 43-2a including a positive electrode active material, negative electrodes 43-1b and 43-2b including a negative electrode active material, and positive electrodes 43-1a and 43-2a. The separators 43-1c and 43-2c are interposed between the negative electrodes 43-1b and 43-2b and transmit ions but do not transmit electrons. It is stacked in the direction (X direction in FIG. 14) and stored inside the exterior body. The positive electrodes 43-1a and 43-2a, the negative electrodes 43-1b and 43-2b, and the separators 43-1c and 43-2c all have a disc shape with two holes.

  The current collectors 47-1 and 47-2 are made of stainless steel, and rod-shaped shaft portions 47-1a and 47-2a and stopper portions 47- attached to one ends of the shaft portions 47-1a and 47-2a. 1b, 47-2b. The shaft portions 47-1a and 47-2a of the current collectors penetrate the electrode bodies 43-1 and 43-1 in the axial direction of the exterior bodies 45-1 and 45-2 (the X direction in FIG. 14), respectively. ing. Further, thread grooves are formed on the side surfaces of the current collectors 47-1 and 47-2 to form screw portions.

  In the first battery 41-1, the outer diameter 43-1ac of the positive electrode 43-1a is smaller than the inner diameter 45-1a of the outer package 45-1, and the positive electrode 43-1a and the outer package 45-1 are not in contact (FIG. 14 (b)). On the other hand, the outer diameter 43-1bc of the negative electrode 43-1b is larger than the inner diameter 45-1a of the outer package 45-1, and the outer periphery 43-1bc of the negative electrode is in contact with the inner surface 45-1a of the outer package 45-1. It is electrically connected to the body 45-1.

  The diameter of one hole 43-1ab provided in the positive electrode 43-1a is smaller than the outer diameter of the shaft portion 47-1a, and the positive electrode 43-1a is in contact with and electrically connected to the shaft portion 47-1a. On the other hand, the diameter of the other hole 43-1aa provided in the positive electrode 43-1a is larger than the outer diameter of the shaft portion 47-2a, and the positive electrode 43-1a is electrically insulated without contacting the shaft portion 47-2a. Yes.

  The diameter of one hole 43-1bb provided in the negative electrode 43-1b is smaller than the outer diameter of the shaft portion 47-2a, and the negative electrode 43-1b is in contact with and electrically connected to the shaft portion 47-2a. Yes. On the other hand, the diameter of the other hole 43-1ba provided in the negative electrode 43-1b is larger than the outer diameter of the shaft portion 47-1a, and the negative electrode 43-1b is electrically insulated without contacting the shaft portion 47-1a. Yes.

  In the second battery 41-2, the outer diameter 43-2ac of the positive electrode 43-2a is larger than the inner diameter 45-2a of the outer package 45-2, and the outer periphery 43-2ac of the positive electrode is the inner surface 45-2a of the outer package 45-2. And is electrically connected to the exterior body 45-2. On the other hand, the outer diameter 43-2bc of the negative electrode 43-2b is smaller than the inner diameter 45-2a of the outer package 45-2, and the negative electrode 43-2b and the outer package 45-2 are not in contact with each other.

  The diameter of one hole 43-2aa provided in the positive electrode 43-2a is smaller than the outer diameter of the shaft portion 47-1a, and the positive electrode 43-2a is in contact with and electrically connected to the shaft portion 47-1a. On the other hand, the diameter of the other hole 43-2ab provided in the positive electrode 43-2a is larger than the outer diameter of the shaft portion 47-2a, and the positive electrode 43-2a is electrically insulated without contacting the shaft portion 47-2a. Yes.

  The diameter of one hole 43-2ba provided in the negative electrode 43-2b is smaller than the outer diameter of the shaft portion 47-2a, and the negative electrode 43-2b is in contact with and electrically connected to the shaft portion 47-2a. Yes. On the other hand, the diameter of the other hole 43-2bb provided in the negative electrode 43-2b is larger than the outer diameter of the shaft portion 47-1a, and the negative electrode 43-2b is electrically insulated without contacting the shaft portion 47-1a. Yes.

  As described above, in the first battery 41-1, the first exterior body 45-1 serves as a negative electrode terminal, and the first current collector 47-1 serves as a positive electrode terminal. On the other hand, in the second battery 41-2, the second exterior body 45-2 serves as a positive electrode terminal, and the second current collector 47-2 serves as a negative electrode terminal. Since the first exterior body 45-1 and the stop portion 47-2b of the second current collector are in contact with each other at the bottom of the exterior body 45-1, the first exterior body 45-1 eventually functions as a negative electrode terminal. And since the 2nd exterior body 45-2 and the stop part 47-1b of the 1st collector are contacting in the bottom part of the exterior body 45-2, the 2nd exterior body 45-2 eventually functions as a positive electrode terminal. .

  As described above, according to the present invention, in the two batteries 41-1 and 41-2, the outer diameter dimensions of the electrodes 43-1a, 43-2a, 43-1b, and 43-2b with the connection piece 44 as a boundary. The stacked electrode bodies are used in common by changing the dimensions of the holes.

FIG. 15A shows a connection diagram in the case where an assembled battery is configured using the laminated battery 41. The heat sink 49 (see FIG. 15B) is provided with holes 49a for attaching the outer body 45 of the laminated battery 41, and the outer bodies 45-1 and 45-2 having different polarities are attached to the adjacent holes 49a. . The heat generated in the laminated battery 41 is transmitted to the heat radiating plate 49 and is cooled by cooling air from a separately provided blower 49b. The heat sink also acts as a series-parallel conductor of the laminated battery 41.
<Modification>

  FIG. 16 is a schematic cross-sectional view in the axial direction of a laminated battery according to a modification of Example 5 of the present invention. Parts that are the same as those in FIG. 14 will be described as having the same reference numerals unless otherwise specified. The exterior body 45 has an insulating material 46 having a high thermal conductivity on the inside and a double structure having a cylindrical can 42 made of a structural material such as stainless steel on the outside. That is, a ceramic layer (insulator 46) made of alumina is formed on the inner surface 42a of the cylindrical can 42 made of stainless steel by plasma spraying. Since the insulator 46 is made of a material having high thermal conductivity, the heat generated in the electrode bodies 43-1 and 43-2 is transferred to the cylindrical can 42 with a small thermal gradient, so that the temperature inside the laminated battery 41 ′ is increased. It is possible to suppress the rise. The insulator 46 only needs to have a high thermal conductivity and an insulating property, and may be ceramics such as titania, alumina / titania, or diamond.

Since the electrode body 43 is covered with the insulator 46, the connection piece 44 as shown in FIG. 14 is not required. Terminal portions 47-1c and 47-2c projecting on opposite sides of the shaft portions 47-1a and 47-2a are provided on the stopper portions 47-1b and 47-2b of the current collector, and these terminal portions 47-1c and 47-2 are provided. -2c was taken out of the laminated battery 41 ′ through bearings 48-1 and 48-2 made of an insulating material provided on the exterior body 45, and used as a positive electrode terminal and a negative electrode terminal.
Refer to the section of the first embodiment for matters relating to the cooling structure among the operational effects of the present embodiment.

  FIG. 17 is a schematic cross-sectional view in the axial direction of a cylindrical laminated battery (hereinafter simply referred to as a laminated battery) according to Example 6 of the invention. A laminated battery 51 shown in FIG. 17 includes an exterior body 55, a current collector 57 housed in the exterior body, and an electrode body 53 as main components. The exterior body 55 includes a bottomed cylindrical can 52, an insulator 59 disposed on the cylindrical can inner surface 52 a, and a disk-shaped lid member 56 attached to the opening 52 c of the cylindrical can 52. The cylindrical can 52 and the lid member 56 are made of stainless steel, but may be a conductive object such as titanium, carbon, or aluminum in addition to stainless steel. The outer diameter of the lid member 56 is slightly larger than the inner diameter of the opening 52c of the cylindrical can 52, and the lid member 56 is tightly fitted in the cylindrical can opening 52c after the electrode body 53 is stored.

  The electrode body 53 includes a positive electrode 53a including a positive electrode active material, a negative electrode 53b including a negative electrode active material, and a separator 53c that is interposed between the positive electrode 53a and the negative electrode 53b and transmits ions but does not transmit electrons. . Note that an electrolytic solution (not shown) is held in the separator 53c. The electrode body 53 is stacked in the axial direction of the cylindrical can 52 (X direction in FIG. 17) and housed in the exterior body 55. Here, a stainless steel partition wall 54 is inserted between the adjacent electrode bodies 53. Since the partition wall 54 is a metal, it allows electrons (electricity) to pass but does not allow ions to pass therethrough, so that the adjacent electrode bodies 53 are electrically connected in series with each other. The output voltage of the stacked battery 51 is determined by the number of stacked electrode bodies 53. In the present embodiment, the terminal voltage of the unit battery composed of one electrode body 53 is 3.6 V, and the stacked battery 51 according to the present embodiment is formed by stacking 50 unit batteries. 180V.

  The current collector 57 has a shaft portion 57a protruding like a rod and a plate portion 57b attached to one end of the shaft portion 57a and formed in a disk shape. The current collector plate portion 57b is provided in a facing direction so as to sandwich the stacked electrode bodies 53. The shaft portion 57b passes through holes 58a and 58b provided at the center of the lid member 56 and the center of the cylindrical can bottom portion 52b, respectively, and protrudes outward from the laminated battery 51. The positive electrode terminal 57ca and the negative electrode terminal 57cb are respectively provided. Function as. A bearing 58 is mounted in the through holes 58a and 58b through which the shaft portion 57a passes. The bearing 58 is made of an insulating material and prevents the shaft portion 57b from coming into contact with the exterior body 55 and being electrically short-circuited. The current collector 57 is made of stainless steel.

  The partition wall 54, the positive electrode 53a, the negative electrode 53b, and the separator 53c all have a disk shape, and the outer diameters 53aa and 53ba of the positive electrode 53a and the negative electrode 53b are larger than the inner diameter 55a of the outer package 55. The exterior body 55 is in contact with pressure. Preferably, the outer diameters 53aa and 53ba of the positive electrode 53a and the negative electrode 53b are 100 μm larger than the inner diameter 55a of the outer package 55.

An insulator 59 was formed on the inner surface 52a of the cylindrical can 52 by plasma spraying a ceramic layer made of alumina. Since the insulator 59 is made of a material having high thermal conductivity, the heat generated by the electrodes 56a and 56b is transmitted to the cylindrical can 52 with a small thermal gradient, and the temperature rise inside the laminated battery 51 can be suppressed. It becomes. Furthermore, the insulator 59 prevents the positive electrode 53a and the negative electrode 53b from being electrically short-circuited. Since the insulator 59 is made of a material having a high thermal conductivity, the heat generated in the electrodes 53a and 53b is transferred to the cylindrical can 52 with a small thermal gradient, so that it is possible to suppress the temperature rise inside the laminated battery. Become. The insulator 46 only needs to have a high thermal conductivity and an insulating property, and examples thereof include ceramics such as titania and alumina / titania. They have good insulation and dielectric strength (about 100 V / mm), high thermal conductivity (about 7 × 10 ⁻³ cal / cm / sec · ° C.), and large mechanical strength (Rockwell hardness of 50 or more). These ceramic layers forming the insulator 59 were processed using a plasma spraying method. The insulator 59 may be an insulating material having high thermal conductivity, and may be diamond.
Refer to the section of the first embodiment for matters relating to the cooling structure among the operational effects of the present embodiment.
<Test results>

  The laminated lithium secondary battery according to Example 1 of the present invention was charged at a rate of 0.1 C and a rate of 30 C, and the temperature of the outer surface of the laminated battery was examined after full charge. In the temperature measurement, the surface of the battery outer package was measured with a commercially available radiation thermometer. When measuring temperature, a test was conducted in a windless state. Further, as a comparative example, a wound-type lithium secondary battery (lithium secondary battery having the structure shown in FIG. 1) was also tested in the same manner as the stacked lithium secondary battery according to Example 1 of the present invention. did.

  First, as a result of charging at a rate of 0.1 C, the laminated lithium secondary battery according to Example 1 of the present invention or the wound lithium secondary battery has a temperature of 5 ° C. or higher. No temperature increase was observed. However, as a result of charging at a rate of 30 C, the temperature rise of the stacked lithium secondary battery according to Example 1 of the present invention was less than 5 ° C., whereas that of the wound lithium secondary battery was The temperature rise was 16 ° C.

From this test result, the laminated lithium secondary battery according to Example 1 of the present invention has a large thermal conductivity in the battery, and therefore, even if the temperature rises due to charging, the temperature immediately decreases. In the type lithium secondary battery, since the thermal conductivity in the battery is small, it is presumed that even if the temperature increases due to charging, the temperature does not easily decrease.
<Application of battery or battery system>

  Since the laminated non-aqueous secondary battery of the present invention is a non-aqueous secondary battery, the operating voltage per unit cell is high, and even when charging / discharging at a high energy density, the battery has little heat storage and is special. Since a laminated battery can be easily configured without the need for equipment, it can be used not only as a power source for electric tools, automobiles, etc., but also for use in applications such as electrical equipment, electrical products, or vehicles. Become. It can also be used as a backup power source.

  For electrical equipment, electrical products, or vehicles, for example, air conditioners, washing machines, TVs, refrigerators, freezers, air conditioners, laptop computers, computer keyboards, computer displays, desktop computers, laptop computers, CRT monitors, personal computers Rack, printer, integrated computer, mouse, hard disk, computer peripherals, iron, clothes dryer, window fan, walkie-talkie, blower, ventilator, TV, music recorder, music player, oven, range, toilet seat with washing function, hot air Heater, Car component, Car navigation system, Flashlight, Humidifier, Portable karaoke machine, Exhaust fan, Dryer, Dry cell, Air purifier, Mobile phone, Emergency light, Game machine, Sphygmomanometer, Coffee mill, Coffee maker, Kotatsu, Copy machine , Disc changer, la Oh, shaver, juicer, shredder, water purifier, lighting equipment, dehumidifier, dish dryer, rice cooker, stereo, stove, speaker, trouser press, vacuum cleaner, body fat scale, weight scale, health meter, movie player, electric Carpet, electric kettle, rice cooker, electric razor, table lamp, electric kettle, electronic game machine, portable game machine, electronic dictionary, electronic notebook, microwave oven, electromagnetic cooker, calculator, electric cart, electric wheelchair, electric tool, electric Toothbrush, Anka, Haircut, Phone, Clock, Intercom, Air Circulator, Electric Shock Insulator, Copying Machine, Hot Plate, Toaster, Dryer, Electric Drill, Water Heater, Panel Heater, Crusher, Soldering Iron, Sewing Machine, Video Camera, video deck, facsimile, fan heater, food processor , Futon dryer, headphones, electric kettle, hot carpet, hot plate, microphone, massage machine, bean bulb, mixer, sewing machine, mochi machine, floor heating panel, lantern, remote control, cold storage, water heater, refrigeration stocker, air cooler , Word processors, whisks, electronic musical instruments, motorcycles, toys, lawn mowers, uki, bicycles, automobiles, hybrid cars, electric cars, railways, ships, airplanes, emergency storage batteries, etc.

  The laminated battery according to the present invention can be suitably used as a secondary battery not only for industrial use but also for consumer use.

DESCRIPTION OF SYMBOLS 1 Storage battery 2 Battery case 3 Positive electrode 4 Negative electrode 5 Separator 6 Cap 7 Sealing plate 11 Cylindrical laminated battery 12 Cylindrical can (a: side part inner surface)
13 Electrode body (a: positive electrode, b: negative electrode, c: separator)
14 Insulating plate 15 Exterior body 16 Lid member 17 Current collector 18 Bearing 20 Assembly battery 21 Pipe laminated battery 22 Circular tube (a: inner surface)
23 electrode body (a: positive electrode, b: negative electrode, c: separator)
24 Insulating member 25 Exterior body 26 Cover member 27 Current collector 28 Bearing 29 Connection fitting 41 Cylindrical laminated battery 42 Cylindrical can 43 Electrode body (a: positive electrode, b: negative electrode, c: separator)
44 Connection piece 45 Exterior body 46 Insulator 47 Current collector 48 Bearing 49 Heat sink 51 Cylindrical laminated battery 52 Cylindrical can (a: side inner surface)
53 Electrode body (a: positive electrode, b: negative electrode, c: separator)
54 Partition 55 Exterior body 56 Lid member 57 Current collector 58 Bearing 59 Insulator 60 Battery assembly 61 Pipe laminated battery 62 Circular tube (a: inner surface)
63 electrode body (a: positive electrode, b: negative electrode, c: separator)
64 Nut 65 Exterior body 66 Cover member 67 Current collector 68 Sealing material 69 Bracket 70 Battery pack 71 Square laminated battery 72 Body member (a: inner surface)
73 Lid member 74 Electrode body (a: positive electrode, b: negative electrode, c: separator)
75 Exterior body 76 Insulation plate 77 Current collector 78 Terminal plate 79 Fan 80 Sealing material 90 Cylindrical laminated battery 91 Connection plate 92 Cylindrical can (a: inner side surface, b: bottom)
93 electrode body (a: positive electrode, b: negative electrode, c: separator)
94 Insulating sheet 95 Round bar 96 Lid member (a: positive terminal, b: bottom)
97 Current collector (a: top, b: bottom, c: screw)
98 Press plate 99 Insulation material

In order to achieve the above-described object, the laminated battery according to the present invention includes a positive electrode containing a positive electrode active material and a negative electrode containing a negative electrode active material in a cylindrical outer package, which transmit ions but transmit electrons. A battery provided with an electrolyte solution, which is laminated in the axial direction of the outer package through a non-permeable separator, and is an electrode of either the positive electrode or the negative electrode and contacts the inner surface of the outer package. A first electrode that is in contact and electrically connected, and a second electrode that is the other electrode and is not in contact with the inner surface of the exterior body, and the conductive current collector includes the positive electrode The negative electrode and the separator are penetrated in the axial direction of the exterior body, the second electrode is in contact with and electrically connected to the current collector, and the first electrode is connected to the current collector. contact with Orazu and the current collector, by an adhesive and the second electrode It has been engaged. In the laminated battery according to the present invention, it is preferable that the electrolytic solution contains a non-aqueous electrolyte.

In the laminated battery according to the present invention, a groove is formed on the side surface of the current collector, the groove of the current collector is a screw groove, and the diameter of the valley of the screw is provided in the second electrode. collector is larger than the diameter of the hole penetrating (Figure 4).

Stacked battery according to the present invention, the adhesive, the consist resin and carbon powder that does not dissolve in the electrolytic solution, the mixture ratio, when the entirety is taken as 100 mass%, the resin does not dissolve in the electrolyte solution 30 It is preferable that it is 90 mass% and carbon powder is 10-70 mass%. The resin that does not dissolve in the electrolytic solution is more preferably polyimide .

In the laminated battery according to the present invention, the outer casing may be a bottomed cylinder with a lid (FIG. 3), the outer casing is a bottomed container having a substantially rectangular cross section, and the opening of the container May be provided (FIG. 8). According to this configuration, the exterior body may be a can.

Laminated cell system according to the present invention includes a bottom portion of the container of the cell stack, it is laminated in a direction in which the lid member of the stacked battery adjacent faces, is constituted by connecting a plurality of stacked cells in series (FIG. 9).

In the laminated battery according to the present invention, the exterior body includes a cylindrical metallic body portion and two lid portions covering the axial opening of the body portion, and the current collector is the lid portion. (FIG. 10).

The connection fitting according to the present invention is a columnar metal connection fitting arranged between stacked batteries, and the connection fitting is provided with a connection hole in the axial direction on the bottom and top surfaces of the connection fitting. The end of the current collector of one stacked battery can be fitted into the provided connection hole, and the end of the current collector of the other stacked battery is the insulator in the connection hole provided in the bottom surface. It is possible to connect the stacked batteries adjacent to each other.

The laminated battery system according to the present invention is formed by connecting a plurality of laminated batteries via the connection fitting . That is, in the laminated battery, a plurality of laminated batteries can be connected in series by fitting the current collector penetrating the first lid portion into the connection hole of the adjacent laminated battery.

In the laminated battery according to the present invention, the exterior body includes a cylindrical metallic trunk, and an insulating first lid and a second lid that cover the axial opening of the trunk. The current collector includes a rod portion and a stop portion formed at one end of the rod portion, and the rod portion penetrates the positive electrode, the negative electrode, and the separator in the axial direction of the exterior body, and the rod at the other end parts are supported on the first cover portion, the stopper portion is in contact with the second cap portion.

The laminated battery system according to the present invention is a laminated battery system in which a plurality of laminated batteries are connected via a metal bracket, the bracket having two holes, and one of the adjacent laminated batteries. The trunk portion is attached to one hole of the bracket, the rod portion of the other laminated battery is attached to the other hole of the bracket, and adjacent laminated batteries are connected in series via the bracket. Is done.

Stacked battery according to the present invention, arranged push plate across said positive and negative electrode and the electrode group consisting of a separator are laminated in the axial direction of said outer body, ing to hold the electrode group by the push plate.

Stacked battery according to the invention, arbitrary preferred that a lithium secondary battery. The nonaqueous laminated battery is preferably a lithium secondary battery. By using lithium ions, the operating potential and the discharge capacity can be increased.

In the laminated battery according to the present invention, the positive electrode contains lithium iron phosphate (LiFePO ₄ ) using CMC as a band . CMC is an abbreviation for carboxymethylcellulose. Since the LiFePO ₄ positive electrode using CMC as a binder uses CMC as a binder, there is little binder swelling due to the electrolyte even under a high temperature environment, and an electrode can be produced without using an organic solvent. Therefore, even in a high temperature environment, high output characteristics can be maintained, and the binder is preferable from the viewpoint of cost and environment. For example, in the case of a LiFePO ₄ positive electrode using polyvinylidene fluoride (PVdF) as a binder, PVdF swells in a high-temperature environment, so that the impedance of the electrode increases. Therefore, it is preferable to use CMC because the output characteristics and cycle life characteristics of the battery are degraded. Further, by using LiFePO ₄ as an active material, there is no oxygen release due to decomposition of the active material even in a high temperature environment, and high temperature durability is improved. For the binder, SBR, PVA, fluororesin, acrylic resin, or the like may be added to CMC to increase the strength of the binder. The positive electrode is composed of an active material, a binder, and a conductive agent added as necessary. When the mixing ratio is 100% by mass as a whole, the active material is 75 to 98% by mass and the binder is 2 to 25% by mass. The conductive agent is preferably 0 to 10% by mass.

In the method for assembling a laminated battery according to the present invention, a round bar having an outer diameter smaller than the diameter of a thread valley formed on a side surface of a current collector is interposed between a positive electrode, a negative electrode, and the positive electrode and the negative electrode. a separator, assembling the electrode assembly stacked sequentially inserted. Then, by arranging the push plate across said electrode group stacked holding the electrode group. Then, pressure is applied to the pressing plate to compress the electrode group, the round bar is pulled out while maintaining the compressed state, and the current collector is screwed into the electrode group instead of the round bar, and the pressing unit is pressed. by screwing the plate to the current collector assembled electrode assembly while maintaining the compressed state of the electrode group. Then, the electrode assembly is press-fitted into the exterior body, air is vented, and an electrolytic solution is injected.
According to this assembling method, the electrode assembly is press-fitted into an exterior body composed of a cylindrical can with a bottom, and after the electrolyte is injected, the cylindrical can is sealed with the lid member to seal the battery.

Method of assembling a laminated battery according to the present invention, the round bar having a diameter smaller than the outer diameter of the screw formed on the side surface of the collector trough, said during a positive electrode, a negative electrode, the positive electrode and the negative electrode Interposing separators are sequentially inserted and stacked and compressed to assemble the electrode group . Then, the round bar is pulled out while maintaining the compressed state, and the current collector is screwed in place of the round bar to assemble the electrode assembly. Then, the electrode assembly is press-fitted into the exterior body, air is evacuated, an electrolyte is injected, and then the electrode assembly is sealed inside the exterior body with a lid member that acts as a push plate.
According to this assembling method, the electrode assembly is press-fitted into the pipe-shaped exterior body, and then the exterior body opening is covered with the lid member to seal the laminated battery.

In the production of the electrode assembly according to the present invention,
By supplying a current to the electrolytic solution, by passing a current through an electrode assembly formed by stacking a plurality of electrode groups composed of a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode , A method of reducing the irreversible capacity by doping an electrode in contact with the outer package with an alkali metal is effective .

The electrode assembly B is inserted in the axial direction of the cylindrical can 92 (X direction in FIG. 6). The outer diameter of the negative electrode 93b is smaller than the inner diameter of the cylindrical can 92, and the outer periphery 93bb of the negative electrode and the inner surface 92a of the cylindrical can are not in contact with each other. On the other hand, the outer diameter of the positive electrode 93a is larger than the inner diameter of the cylindrical can 92, the outer periphery 93ab of the positive electrode is in contact with the inner surface 92a of the cylindrical can 92, and the positive electrode 93a and the cylindrical can 92 are electrically connected. The upper opening of the cylindrical can 92 is covered with a lid member 96 so that the electrode assembly B can be sealed inside the cylindrical can 92. An insulating material 99 is disposed between the lid member 96 and the cylindrical can 92 to prevent the lid member 96 and the cylindrical can 92 from contacting and electrically short-circuiting.

An insulating sheet 94 is disposed on the cylindrical can bottom portion 92b, and an end 97b of the current collector is in direct contact with the cylindrical can bottom portion 92b to prevent the current collector 97 and the cylindrical can 92 from being electrically short-circuited. doing. A connecting plate 91 made of a plate-like elastic body that protrudes downward is attached to the other end 97a of the current collector. The end portion 91 a of the connection plate is in contact with the bottom surface 96 b of the lid member and is urged downward by the lid member 96. As a result, the current collector 97 and the lid member 96 are electrically connected via the connection plate 91.
The protrusion 96a provided at the center of the lid member 96 functions as a negative electrode terminal. The cylindrical can 92 functions as a positive electrode terminal.

Next, a method for assembling the laminated battery according to the present invention will be described with reference to FIG. Sequentially inserted into a round bar 95 having an outer diameter of 3.5 mm smaller than the diameter (d) of the thread valley formed on the side surface of the current collector 97 so that the separator 93c is interposed between the positive electrode 93a and the negative electrode 93b. Then, after the electrode bodies 93a, b, c are stacked, the push plates 98a, 98b are arranged on both ends of the stacked electrode groups to hold the electrode groups, and the electrode current collector A is assembled. Then, the electrode group is compressed via the push plates 98a and 98b, and the round bar 95 is pulled out while maintaining the compressed state. Instead, the current collector 97 is pressed against the electrode group held by the push plates 98a and 98b. Screw in by rotating while applying. At this time, the push plate 98a, b is made possible to assemble the electrode assembly B while maintaining the compressed state of the electrode group since it is screwed to the collector 97. Then, the electrode assembly B is press-fitted into the cylindrical can 92, air is evacuated, and an electrolytic solution is injected. After injection of the electrolytic solution, a lid member 96 is attached to the opening of the cylindrical can 92, and the opening of the cylindrical can 92 is crimped to seal the laminated battery.
<Example 2>

Shows the engagement Ru laminated battery in Example 2 of the present invention in FIG. As shown in the plan view of FIG. 8B, the battery as a whole has a square shape. A rectangular laminated battery 71 shown in FIG. 8A includes an outer package 75 including a body member 72 and a lid member 73, a positive electrode 74a including a positive electrode active material, a negative electrode 74b including a negative electrode active material, and positive and negative electrodes 74a and 74b. It has an electrode body 74 made up of a separator 74c, which is interposed between them and transmits ions but does not transmit electrons, as a main component. The body member 72 is a bottomed rectangular container, and the opening 72c is covered with a lid member 73 so that a sealed space can be formed inside the body member 72. The body member 72 and the lid member 73 are made of stainless steel, but may be other metals.

Claims (29)

A positive electrode including a positive electrode active material and a negative electrode including a negative electrode active material are laminated in the axial direction of the outer package through a separator that transmits ions but does not transmit electrons. And a battery equipped with an electrolyte containing a non-aqueous electrolyte,
A first electrode that is either the positive electrode or the negative electrode that is in contact with and electrically connected to the inner surface of the exterior body, and the other electrode that is in contact with the inner surface of the exterior body. With no second electrode,
A conductive current collector passes through the positive electrode, the negative electrode, and the separator in the axial direction of the exterior body, and the second electrode is in contact with and electrically connected to the current collector. The laminated battery is such that the first electrode is not in contact with the current collector.   The laminated battery according to claim 1, wherein a groove is formed on a side surface of the current collector.   The stacked battery according to claim 2, wherein the current collector groove is a screw groove, and a diameter of a screw trough of the current collector is larger than a diameter of a hole through which the current collector provided in the second electrode passes.   The laminated battery according to claim 1, wherein the current collector is bonded to the second electrode with an adhesive.   The adhesive is composed of a resin and carbon powder that does not dissolve in the electrolytic solution, and the mixing ratio is 100% by mass as a whole. The resin that does not dissolve in the electrolytic solution is 30 to 90% by mass, and the carbon powder is 10%. It is -70 mass%, The laminated battery as described in any one of Claims 1-4.   The laminated battery according to any one of claims 1 to 5, wherein the resin that does not dissolve in the electrolytic solution is polyimide.   The laminated battery according to claim 1, wherein the outer package is a bottomed cylinder with a lid.   The laminated battery according to any one of claims 1 to 6, wherein the exterior body includes a bottomed container having a substantially rectangular cross section and a lid member that covers an opening of the container.   The stacked battery system according to claim 8, wherein the bottom of the container of the stacked battery and the lid member of the adjacent stacked battery are stacked in a facing direction, and a plurality of stacked batteries are connected in series.   The said exterior body has a cylindrical metallic trunk | drum and two cover parts which cover the axial direction opening part of the said trunk | drum, The said electrical power collector has penetrated the said cover part. The laminated battery as described in any one of -6.   A columnar metal connection fitting disposed between the laminated batteries according to claim 10, wherein the connection fitting is provided with a connection hole in an axial direction on the bottom surface and the top surface of the connection fitting. The end of the current collector of one stacked battery can be fitted into the connected hole, and the end of the current collector of the other stacked battery is inserted through the insulator into the connection hole provided on the bottom surface. A fitting that can be fitted to each other and can connect adjacent stacked batteries.   The multilayer battery system according to claim 10, wherein a plurality of multilayer batteries are connected through the connection fitting according to claim 11.   The exterior body has a cylindrical metallic trunk, and an insulating first lid and a second lid that cover the axial opening of the trunk, and the current collector includes a rod and the lid A stop portion formed at one end of the rod portion, and the rod portion passes through the positive electrode, the negative electrode, and the separator in the axial direction of the exterior body, and the first portion at the other end of the rod portion. The laminated battery according to any one of claims 1 to 6, being supported by a lid, and the stopper being in contact with the second lid. A stacked battery system comprising a plurality of the stacked batteries according to claim 13 connected via a metal bracket,
The bracket has two holes,
The body part of one adjacent laminated battery is attached to one hole of the bracket, and the rod part of the other laminated battery is attached to the other hole of the bracket, and is adjacent via the bracket. A stacked battery system in which stacked batteries are connected in series. A positive electrode including a positive electrode active material and a negative electrode including a negative electrode active material are laminated in the axial direction of the outer package through a separator that transmits ions but does not transmit electrons. A first electrode that is either the positive electrode or the negative electrode that is in contact with and electrically connected to the inner surface of the exterior body, and the other electrode that is in contact with the inner surface of the exterior body. A laminated battery comprising a second electrode that is not
A first laminated battery in which the first electrode is a negative electrode and the second electrode is a positive electrode;
A laminated battery combining a second laminated battery in which the second electrode is a negative electrode and the first electrode is a positive electrode;
A conductive first current collector and a second current collector are inserted through the positive electrode, the negative electrode, and the separator in the axial direction of the exterior body, and the first current collector is connected to the negative electrode. The second current collector is in contact with and electrically connected to the positive electrode and not in contact with the negative electrode. The laminated battery as described in any one of 1-6.   The laminated battery according to claim 15, wherein the outer package is a bottomed cylinder.   The first current collector is in contact with the first exterior body of the first multilayer battery, the second current collector is in contact with the second exterior body of the second multilayer battery, and the first exterior body The laminated battery as described in any one of Claim 15 or 16 with which the body and the said 2nd exterior body were connected via the insulator.   The laminated battery according to any one of claims 15 to 17, wherein an inner surface of the exterior body is an insulating material having high thermal conductivity. A stacked battery system comprising a plurality of the stacked batteries according to claim 15 connected to each other,
A plurality of the laminated batteries are arranged between the current collector plates provided facing each other, and the positive electrode terminal connected to the positive electrode of the laminated battery is in contact with and electrically connected to one of the current collector plates, A laminated battery system in which a negative electrode terminal connected to the negative electrode of the laminated battery is in contact with and electrically connected to the other current collector plate.   The laminated battery system according to claim 19, further comprising means for sending cooling air in a direction parallel to the current collector plate.   A cylindrical exterior body made of an insulating material with high thermal conductivity is interposed with a separator that transmits ions but does not transmit electrons between a positive electrode containing a positive electrode active material and a negative electrode containing a negative electrode active material. A plurality of electrode bodies are laminated in the axial direction of the exterior body, and a metal partition is provided between the adjacent electrode bodies, and the positive electrode, the negative electrode, and the partition are the exterior A laminated battery in contact with the inner surface of the body.   The laminated battery according to claim 21, wherein the outer package is a cylinder with a bottom with a lid.  14. The structure according to claim 1, wherein a pressing plate is disposed at both ends of the electrode group composed of the positive and negative electrodes and the separator laminated in the axial direction of the outer package, and the electrode group is held by the pressing plate. The laminated battery according to one item.   The laminated battery or the laminated battery system according to any one of claims 1 to 23, wherein the laminated battery is a lithium secondary battery.   The laminated battery or the laminated battery system according to claim 1, wherein the positive electrode contains lithium iron phosphate using CMC as a band.   The electrical installation using the laminated battery or laminated battery system as described in any one of Claims 1-25.   The electrodes are stacked after sequentially inserting electrodes into a round bar having the same outer diameter as the thread valley formed on the side surface of the current collector so that the separator is interposed between the positive electrode and the negative electrode. The electrode plate is held by arranging the pressing plates at both ends of the electrode. Then, pressure is applied to the push plate to compress the electrode group, and the round bar is pulled out while maintaining the compressed state. Instead, the current collector is screwed into the electrode group, and the push plate is moved to the current collector. The electrode assembly is assembled while the electrode group is screwed to keep the electrode group in a compressed state. And the assembly method of the laminated battery which press-fits the said electrode assembly inside the said exterior body, vents air, and inject | pours electrolyte solution.   After the electrodes are stacked and compressed sequentially into a round bar having the same outer diameter as the thread valley formed on the side surface of the current collector so that the separator is interposed between the positive electrode and the negative electrode, the compressed state is changed. The round bar is pulled out while being held, and the current collector is screwed in instead to assemble the electrode assembly. Then, the electrode assembly is press-fitted into the exterior body, the air is evacuated, the electrolyte is injected, and then an assembly of a laminated battery in which the electrode group is sealed inside the exterior body with a lid member that acts as a push plate. Method.   A method of obtaining an electrode assembly in which an irreversible capacity is reduced by supplying an electric current to the electrolytic solution and causing the current to flow through the electrode assembly to dope the second electrode with an alkali metal.

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