JP5652386B2 - Nonaqueous electrolyte secondary battery, vehicle, and power storage device - Google Patents

Description

  The present invention relates to a non-aqueous electrolyte secondary battery, a vehicle equipped with a non-aqueous electrolyte secondary battery, and a power storage device.

  Conventionally, lithium ion secondary batteries are well known as secondary batteries. A lithium ion secondary battery is configured such that an electrode body formed by laminating an electrode in which an active material layer is formed on a metal foil and a nonaqueous electrolyte in which an electrolyte salt (lithium salt) is dissolved are housed in a case. Yes.

Among such lithium ion secondary batteries, a nonaqueous electrolyte in which LiAsF ₆ (lithium hexafluoroarsenate) is dissolved in 1,3-dioxolane is used, so that the temperature in the case is about 100 ° C. When it becomes above, there exists what gelatinizes a nonaqueous electrolyte by a polymerization reaction (for example, patent documents 1). In the lithium ion secondary battery of Patent Document 1, the internal resistance of the lithium ion secondary battery is increased by the gelation of the nonaqueous electrolyte, thereby suppressing the temperature rise in the lithium ion secondary battery. With such a configuration, in the lithium ion secondary battery of Patent Document 1, the occurrence of thermal runaway is suppressed.

JP-A-7-78635

  However, in the lithium ion secondary battery of Patent Document 1, when the battery voltage becomes 4 V or higher, the nonaqueous electrolyte is decomposed and gelled mainly around the positive electrode, so the volume energy density of the lithium ion secondary battery is reduced. It is a limitation when improving. Such a problem also occurs in a power storage device such as a non-aqueous electrolyte capacitor (non-aqueous electrolyte capacitor).

  This invention was made paying attention to the problem which exists in the said prior art, The objective is the nonaqueous electrolyte secondary battery which can improve a volume energy density, suppressing generation | occurrence | production of thermal runaway. Another object is to provide a vehicle and a power storage device.

In order to solve the above-mentioned problem, the invention according to claim 1 accommodates in a case an electrode body in which an electrode formed with an active material layer forms a layer, and a non-aqueous electrolyte in which an electrolyte salt is dissolved in a non-aqueous solvent. A non-aqueous electrolyte secondary battery comprising: a polymerizing agent that gels the non-aqueous electrolyte by a polymerization reaction; and a material having a melting point lower than a thermal runaway temperature. A separating member that separates from the electrode, and the polymerization agent is Ti alkoxide .

  Note that thermal runaway is spontaneous, such as when a specific member constituting a secondary battery generates heat, triggered by internal short circuit or overcharge, and other members generate heat due to heat generated by the specific member. The state where the temperature of the secondary battery continues to rise. The thermal runaway temperature refers to a temperature at which a heat runaway heat generation cycle is started.

  According to this, the polymerizing agent that gels the nonaqueous electrolyte by the polymerization reaction is isolated from the nonaqueous electrolyte and the electrode by the isolation member. For this reason, the nonaqueous electrolyte is decomposed and gelled around the positive electrode even when the battery voltage is increased as compared with the conventional configuration using a nonaqueous electrolyte containing a polymerization agent in advance. Can be suppressed. When the temperature in the case rises and reaches the melting point of the separating member, the separating member is melted and the separated polymerization agent is released. For this reason, the non-aqueous electrolyte is gelled by the polymerization reaction by the polymerization agent, thereby increasing the internal resistance and suppressing the temperature rise. Therefore, the volume energy density can be improved while suppressing the occurrence of thermal runaway.

According to a second aspect of the invention, the non-aqueous electrolyte secondary battery of claim 1, wherein the isolation member, together with the enclosing said polymerization agent, is disposed between the electrode body case It is a summary.

  According to this, since the separating member containing the polymerization agent is disposed between the electrode body and the case where the temperature is likely to rise, the temperature of the separating member is likely to rise as the temperature of the electrode body rises. Thus, the isolation member can be easily melted in conjunction with the temperature rise of the electrode body.

According to a third aspect of the present invention, in the nonaqueous electrolyte secondary battery according to the second aspect, the isolation member is disposed along an end of the electrode body on the side where the current collecting terminal is fixed. It is a summary.
The invention according to claim 4 is the nonaqueous electrolyte secondary battery according to any one of claims 1 to 3, wherein the electrode body is formed by winding an electrode sheet having a long sheet shape. The gist of the invention is that the isolation member is disposed at the center of the electrode body.

  According to this, the separating member is disposed at the center of the electrode body formed by winding the electrode sheet. For this reason, as the temperature of the electrode body rises, the temperature of the separating member also rises easily, and the separating member can be easily melted in conjunction with the temperature rise of the electrode body.

  The gist of the invention according to claim 5 is the non-aqueous electrolyte secondary battery according to any one of claims 1 to 4, wherein the isolation member is a film made of polyethylene. According to this, it is possible to release the polymerization agent by melting the separating member at a low temperature while ensuring the stability (chemical resistance) against the non-aqueous electrolyte.

The gist of the invention described in claim 6 is that the nonaqueous electrolyte secondary battery according to any one of claims 1 to 5 is mounted in a vehicle.
According to this, the volume energy density can be improved by setting the battery voltage high while suppressing the occurrence of thermal runaway, and the nonaqueous electrolyte secondary battery can be reduced in size and capacity. Therefore, for example, when the capacity is increased as a non-aqueous electrolyte secondary battery, the amount of electric power (usage time) that can be used by one full charge in the vehicle can be improved. In addition, when the size of the nonaqueous electrolyte secondary battery is reduced, the degree of freedom of the location where the secondary battery is installed in the vehicle can be improved.

The invention according to claim 7 is an electricity storage device having an electrode body in which an electrode is layered and a non-aqueous electrolyte in which an electrolyte salt is dissolved in a non-aqueous solvent, wherein the non-aqueous electrolyte is gelled by a polymerization reaction. And a separating member made of a material whose melting point is lower than the thermal runaway temperature, and separating the polymer from the nonaqueous electrolyte and the electrode body, and the polymer is a Ti alkoxide. The gist.

  According to this, the polymerizing agent that gels the nonaqueous electrolyte by the polymerization reaction is isolated from the nonaqueous electrolyte and the electrode by the isolation member. For this reason, the nonaqueous electrolyte is decomposed and gelled around the positive electrode even when the voltage between the electrodes is increased as compared with the conventional configuration using a nonaqueous electrolyte containing a polymerization agent in advance. This can be suppressed. When the temperature of the power storage device rises and reaches the melting point of the isolation member, the isolation member melts and the isolated polymerization agent is released. For this reason, the non-aqueous electrolyte is gelled by the polymerization reaction by the polymerization agent, thereby increasing the internal resistance and suppressing the temperature rise. Therefore, the volume energy density can be improved while suppressing the occurrence of thermal runaway.

  According to the present invention, it is possible to improve the volume energy density while suppressing the occurrence of thermal runaway.

The perspective view which shows a lithium ion secondary battery typically. The disassembled perspective view which shows an electrode body and a polymeric agent pack typically. The perspective view which shows typically the lithium ion secondary battery in another embodiment. The disassembled perspective view which shows typically the electrode body and polymer agent pack in another embodiment. The front view which shows typically the lithium ion secondary battery in another embodiment.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1, a lithium ion secondary battery (hereinafter simply referred to as “secondary battery”) as a nonaqueous electrolyte secondary battery (nonaqueous secondary battery) mounted on a vehicle (for example, an industrial vehicle or a passenger vehicle). 10) includes a case 11 having a generally flat and generally cubic shape. The case 11 is a flat plate assembled to the main body member 12 so as to cover (seal) the main body member 12 formed in a bottomed cylindrical shape (in this embodiment, a square cylindrical shape) and the opening 12a of the main body member 12. The lid member 13 is formed in a rectangular flat plate shape in the present embodiment. In the main body member 12, the corners 11a of the bottom and the four side walls surrounding the bottom are all formed in an R shape.

  The main body member 12 and the lid member 13 are both made of metal (for example, stainless steel or aluminum). Hereinafter, for convenience of explanation, the longitudinal direction of the case 11 indicated by the arrow Y1 in FIG. 1 is indicated as the left-right direction, the short direction (thickness direction) of the case 11 indicated by the arrow Y2 is indicated as the front-rear direction, and the arrow Y3 The height direction of the case 11 to be shown is indicated as the vertical direction.

  The lid member 13 is provided with a positive electrode terminal 15 and a negative electrode terminal 16 having a cylindrical shape (substantially cylindrical shape) projecting upward from the upper surface of the lid member 13. A base end (one end) of a current collecting terminal 17 made of metal (for example, aluminum) and electrically connected to the positive electrode terminal 15 is fixed to the lower surface (inner surface) of the lid member 13. Further, a base end (one end) of a current collecting terminal 18 made of metal (for example, copper) and electrically connected to the negative electrode terminal 16 is fixed to the lower surface (inner surface) of the lid member 13. In the present embodiment, the positive electrode terminal 15, the negative electrode terminal 16, and the current collecting terminals 17 and 18 are in an insulated state from the case 11 (the main body member 12 and the lid member 13).

  In addition, the case 11 is layered with a positive electrode sheet 24 and a negative electrode sheet 25 as electrodes formed by applying an active material to a conductive sheet-like base material with a separator (diaphragm) 23 interposed therebetween. The electrode body 21 is accommodated.

  As shown in FIG. 2, the separator 23 is made of an insulating resin material and is a rectangular porous sheet having a very fine pore structure. More specifically, the separator 23 of the present embodiment has a multilayer structure (three-layer structure in the present embodiment) in which a porous sheet made of polypropylene is sandwiched between porous sheets made of polyethylene. When the separator 23 reaches the melting point of polyethylene constituting the porous sheet (135 ° C. to 140 ° C. in this embodiment), the porous sheet is melted, the pore structure is collapsed, and the pores are blocked. In this case, the separator 23 blocks the passage of ions between the positive electrode sheet 24 and the negative electrode sheet 25 to increase the internal resistance of the secondary battery 10 and suppress the temperature increase of the secondary battery 10. ing. In the following description, the melting point of polyethylene constituting the separator 23 is particularly referred to as a cutoff temperature.

  The positive electrode sheet 24 includes a metal foil 24a (for example, an aluminum foil) as a base material having a rectangular sheet shape, while the negative electrode sheet 25 is a metal as a base material having a rectangular sheet shape. The foil 25a (for example, copper foil) is provided. An active material is applied to the entire surface of both surfaces (front surface and rear surface) of each metal foil 24a, 25a, and an active material layer 26 is formed.

The metal foil 24a is coated with an active material for a positive electrode (for example, LiNi _1/3 Mn _1/3 Co _1/3 O ₂ ), while the metal foil 25a is coated with an active material for a negative electrode (for example, LiC ₆ ) Is applied. Further, in each positive electrode sheet 24, a substantially rectangular positive electrode tab 24b extends upward at the upper left end of the metal foil 24a. On the other hand, in each negative electrode sheet 25, the metal foil 25a A negative electrode tab 25b having a substantially rectangular shape is extended upward at the upper right end portion. The active material layer 26 is not formed on the surfaces of the positive electrode tab 24b and the negative electrode tab 25b.

  The electrode body 21 is formed by laminating a positive electrode sheet 24 and a negative electrode sheet 25 in the front-rear direction (thickness direction) with a separator (diaphragm) 23 interposed therebetween. More specifically, the positive electrode sheet 24 and the negative electrode sheet 25 are alternately arranged as follows: →→ positive electrode sheet 24 → negative electrode sheet 25 → positive electrode sheet 24. In the present embodiment, the front-rear direction indicated by the arrow Y <b> 2 is the stacking direction of the positive electrode sheet 24 and the negative electrode sheet 25.

  As shown in FIG. 1, each positive electrode tab 24 b is offset from the front-rear direction with respect to the tip (the other end) of the current collecting terminal 17 arranged so as to be inserted between the positive electrode tabs 24 b from above. In the (collected) state, they are joined and electrically connected by, for example, ultrasonic joining or spot joining (resistance welding). Similarly, the negative electrode tab 25b was brought close to the front end (the other end) of the current collecting terminal 18 arranged so as to be inserted between the negative electrode tabs 25b from above (from the front and back). ) State, for example, by ultrasonic bonding or spot bonding (specific resistance welding), and are electrically connected.

  The case 11 is filled with a non-aqueous electrolyte (non-aqueous electrolyte) in which a lithium salt as an electrolyte salt is dissolved in an organic solvent (non-aqueous solvent) such as ethylene carbonate or dimethyl carbonate as an electrolyte. Yes. Note that the nonaqueous electrolyte of the present embodiment has a composition that is not decomposed (oxidized and reduced) even when the battery voltage of the secondary battery 10 is 4 V or higher.

  As shown in FIG. 2, the secondary battery 10 of the present embodiment includes a rectangular plate-shaped polymer agent capsule 30 that encloses (encloses) a polymer agent 31 that gels a nonaqueous electrolyte by a polymerization reaction. . The polymerizer capsule 30 is disposed so as to sandwich the electrode body 21 from both sides of the electrode body 21 in the stacking direction (front-rear direction). That is, the polymer capsule 30 is placed between the electrode body 21 and the case 11 (main body member 12) such that the electrode body 21 is in surface contact with the outer surface of the electrode sheet disposed on the outermost side in the stacking direction. It is arranged (inserted) between them.

  The polymerizer capsule 30 of the present embodiment isolates the polymerizer 31 from the nonaqueous electrolyte and the electrode body 21 (the positive electrode sheet 24 and the negative electrode sheet 25) in the case 11. Hereinafter, the polymer capsule 30 will be described in detail.

  The polymer capsule 30 is a resin material (polymer polymer) that is chemically stable with respect to the nonaqueous electrolyte and has a melting point lower than the melting point of polyethylene constituting the separator 23 and the thermal runaway temperature of the secondary battery 10. A resin film 30a as a separating member is formed in a bag shape.

  Here, being chemically stable with respect to the nonaqueous electrolyte means that the resin film 30a is dissolved or decomposed (chemical reaction) in the nonaqueous electrolyte at a temperature equal to or lower than the melting point of the resin film 30a. Is not eluted to the extent that the function of the secondary battery 10 is degraded.

  Further, the thermal runaway of the secondary battery 10 is triggered by, for example, an internal short circuit or overcharge, and the specific member constituting the secondary battery 10 generates heat, and the other member generates heat due to the heat generated by the specific member. Thus, the state where the temperature of the secondary battery 10 continues to rise spontaneously is said. The temperature at which such a heat generation cycle is started becomes the thermal runaway temperature of the secondary battery 10. Note that the thermal runaway temperature of the secondary battery 10 varies depending on the types of members constituting the secondary battery 10 such as the type of active material, the type of nonaqueous electrolyte, and the volume of the case 11. In addition, the thermal runaway temperature is determined by, for example, measuring the temperature at which the secondary battery 10 is heated to start the above-described heat generation cycle, heating each member constituting the secondary battery 10 individually, and spontaneously. It is also possible to measure and estimate the temperature at which the temperature rise starts. The thermal runaway temperature in the secondary battery 10 of the present embodiment is 150 ° C.

  Returning to the description of the polymerizer capsule 30, the resin film 30a (polymerizer capsule 30) of the present embodiment is formed of polyethylene having a melting point of, for example, 95 ° C to 105 ° C. The resin film 30a of the present embodiment is made of a resin material that has an insulating property and does not allow the nonaqueous electrolyte in the case 11 and the encapsulated polymer agent 31 to permeate (pass) each other. The resin film 30a has a thickness of, for example, 100 μm to 200 μm, and preferably 120 μm to 180 μm. In addition, the resin film 30 a is formed in the same shape and size as the separator 23 in front view, corresponding to the size and shape of the separator 23.

The polymer capsule 30 is formed in a bag shape by welding the periphery of two resin films 30a having a rectangular sheet shape by, for example, heat welding or the like, and is formed between the two resin films 30a. The above-described polymerization agent 31 is accommodated in the accommodation space 30b. As the polymerization agent 31, for example, 1,3-dioxolane in which LiAsF ₆ (lithium hexafluoroarsenate) is dissolved so as to be 0.8 mol / L to 1.5 mol / L is used. Moreover, tertiary amines, such as a triethylamine, may be added to the polymerization agent 31, for example as a stabilizer which functions as a polymerization inhibitor.

  In the polymerizing agent 31 having such a composition, when the temperature of the polymerizing agent 31 becomes 105 ° C. to 115 ° C., the polymerization reaction proceeds and gels. In the following description, the temperature at which the polymerization reaction of the polymerization agent 31 is started is referred to as the polymerization temperature. Further, when the polymer agent 31 is in direct contact with the positive electrode sheet 24 (the metal foil 24a and the active material layer 26), when the battery voltage of the secondary battery 10 becomes 4 V or more, Even at a temperature lower than the polymerization temperature, it decomposes around the positive electrode sheet 24 and gels.

  Further, in the polymer capsule 30, when the polymer 31 is released into the case 11, an amount of polymerization necessary for gelling at least a part of the non-aqueous electrolyte, more preferably the whole non-aqueous electrolyte. Agent 31 is enclosed. It should be noted that the amount of the polymerizing agent 31 enclosed in the polymerizing agent capsule 30 is the internal volume of the case 11 (the volume of the nonaqueous electrolyte) and the internal resistance of the secondary battery 10 that is targeted when the nonaqueous electrolyte is gelled. It can be calculated based on the value.

Next, the effect | action of the secondary battery 10 of this embodiment is demonstrated.
First, the case where the internal temperature of the secondary battery 10 (the temperature of the electrode body 21) is lower than the melting point of the resin film 30a will be described. In this case, the polymerizing agent 31 is separated from the non-aqueous electrolyte and the electrode body 21 (positive electrode sheet 24) by the resin film 30a of the polymerizing agent capsule 30.

  For this reason, the polymerization agent 31 is not in direct contact with the positive electrode sheet 24, and even when the battery voltage of the secondary battery 10 is increased (for example, 4 V or more), the polymerization is performed around the positive electrode sheet 24. It can suppress suitably that agent 31 decomposes | disassembles and part or all of nonaqueous electrolyte will gelatinize. Therefore, in the secondary battery 10 of the present embodiment, the volume energy density can be improved.

  Next, a case where the internal temperature of the secondary battery 10 (the temperature of the electrode body 21) is equal to or higher than the melting point of the resin film 30a will be described. In this case, the polymer agent capsule 30 (resin film 30a) in contact with the electrode body 21 dissolves when the melting point is reached by the heat transmitted from the electrode body 21, and the polymer agent 31 separated by the polymer agent capsule 30 is It is discharged into the case 11 and mixed with the nonaqueous electrolyte. Then, the nonaqueous electrolyte mixed with the polymerizing agent 31 starts the polymerization reaction when the temperature of the nonaqueous electrolyte reaches the polymerization temperature of the polymerizing agent 31, and a part or the whole of the nonaqueous electrolyte is gelled. Thereby, in the secondary battery 10 of this embodiment, while the internal resistance of the secondary battery 10 increases, the temperature rise of the secondary battery 10 is suppressed.

  Further, in the present embodiment, even if the temperature rise of the secondary battery 10 is not sufficiently suppressed by the polymerization reaction of the polymerizing agent 31, the internal temperature of the secondary battery 10 reaches the cutoff temperature of the separator 23. The pores in the separator 23 are blocked, and the internal resistance of the secondary battery 10 can be further increased. For this reason, in this embodiment, it can suppress suitably that the internal temperature of the secondary battery 10 reaches thermal runaway temperature.

Therefore, according to the above embodiment, the following effects can be obtained.
(1) The polymerizing agent 31 that gels the nonaqueous electrolyte by a polymerization reaction is isolated from the nonaqueous electrolyte and the electrode body 21 (positive electrode sheet 24) by the polymerizing agent capsule 30 (resin film 30a). Therefore, the nonaqueous electrolyte is decomposed around the positive electrode sheet 24 even when the battery voltage of the secondary battery 10 is increased as compared with the conventional configuration using the nonaqueous electrolyte containing the polymerizing agent 31 in advance. Can be prevented from being gelled. When the temperature in the case 11 (temperature of the electrode body 21) rises and reaches the melting point of the polymer capsule 30 (resin film 30a), the polymer capsule 30 is melted and isolated. Is released. For this reason, the non-aqueous electrolyte is gelled by the polymerization reaction by the polymerization agent 31, the internal resistance is increased, and the temperature rise of the secondary battery 10 can be suppressed. Therefore, the volume energy density can be improved while suppressing the occurrence of thermal runaway.

(2) As the polymerizing agent 31, 1,3-dioxolane in which LiAsF ₆ is dissolved is encapsulated in the polymerizing agent capsule 30. For this reason, the non-aqueous electrolyte can be reliably gelled by the polymerization reaction by the polymerization agent 31.

  (3) The polymer capsule 30 containing the polymer agent 31 is disposed between the electrode body 21 and the case 11 where the temperature is likely to rise. For this reason, the temperature of the polymer capsule 30 is likely to increase as the temperature of the electrode body 21 rises, and can be easily melted in conjunction with the temperature rise of the electrode body 21.

  (4) The resin film 30a forming the polymer capsule 30 is made of polyethylene. For this reason, the polymer agent 31 can be released by melting the resin film 30a at a low temperature while ensuring the stability (chemical resistance) against the nonaqueous electrolyte.

  (5) The polymer capsule 30 is in surface contact with both end surfaces of the electrode body 21 in the stacking direction (front surface and rear surface in the present embodiment). Therefore, when the temperature of the electrode body 21 reaches the melting point of the resin film 30a, the polymerizer capsule 30 can be quickly melted and the nonaqueous electrolyte can be gelled.

  (6) Since the polymerizer capsule 30 is disposed along the flat surfaces (front surface and rear surface) of the case 11, the flat surface of the case 11 is recessed inward due to external impact or the like. Even in the case of deformation, the electrode body 21 can be protected by buffering the impact.

  (7) The melting point of the resin film 30 a is lower than the cutoff temperature of the separator 23. For this reason, even when the temperature rise of the secondary battery 10 is not sufficiently suppressed by the polymerization reaction of the polymerizing agent 31, the internal temperature of the secondary battery 10 reaches the cutoff temperature of the separator 23, thereby causing pores in the separator 23. The internal resistance of the secondary battery 10 can be further increased. Thereby, in this embodiment, it can suppress suitably that the internal temperature of the secondary battery 10 reaches thermal runaway temperature. Therefore, the safety of the secondary battery 10 can be improved.

The embodiment is not limited as described above, and may be embodied as follows, for example.
○ As shown in FIGS. 3 and 4, the electrode body 21 includes a separator 23, a positive electrode sheet 24, and a negative electrode sheet 25 that are formed into a long sheet shape, and in a state where the separator 23 is interposed, The electrode sheet 24 and the negative electrode sheet 25 may be wound in a spiral shape so that the positive electrode sheet 24 and the negative electrode sheet 25 are layered. In this case, as shown in FIG. 4, the length direction (arrow Y4) of the positive electrode sheet 24 is arranged at one end portion (left end portion in this example) in the width direction (shown by the arrow Y1) in the positive electrode sheet 24. A positive electrode tab 24b that protrudes outward (left side) in the width direction is provided so as to extend along On the other hand, in the negative electrode sheet 25, the other end in the width direction (the right end in this example) is extended to the outside in the width direction (right side) so as to extend along the length direction of the negative electrode sheet 25. A protruding negative electrode tab 25b is provided.

  Further, as shown in FIG. 3, the current collecting terminal 17 is inserted between the positive electrode tab 24b from the outer side (left side) of the electrode body 21 in the left-right direction so that the layered positive electrode tab 24b faces each other. Be joined. On the other hand, the current collecting terminal 18 is inserted between the negative electrode tabs 25b from the outer side (right side) in the left-right direction of the electrode body 21, and is joined so that the layered negative electrode tabs 25b face each other.

  In this case, as shown in FIGS. 3 and 4, polymerization is performed so as to extend along the width direction of the positive electrode sheet 24 and the negative electrode sheet 25 at the center (winding center) of the electrode body 21 having a flat shape. An agent capsule 30 may be provided. By comprising in this way, the polymerizer capsule 30 can be easily melted in conjunction with the temperature of the central portion of the electrode body 21 that is likely to store heat. In addition, in the wound electrode body 21 as in this example, a dead space is generated at the center. By disposing the polymerizer capsule 30 in this dead space, the volume energy density of the secondary battery 10 is reduced. The polymerizer capsule 30 can be provided without any problem.

  In addition, when the electrode body 21 is formed by winding the positive electrode sheet 24 and the negative electrode sheet 25, the width direction (direction in which the winding axis extends) of the positive electrode sheet 24 and the negative electrode sheet 25 is arranged in the vertical direction. May be stored in the case 11. In this case, the positive electrode tab 24b and the negative electrode tab 25b are preferably formed on the upper end portion of the electrode body 21 so as to extend upward. Further, the electrode body 21 may be laminated by folding the positive electrode sheet 24 and the negative electrode sheet 25 in a bellows shape with the separator 23 interposed therebetween.

  As shown in FIG. 5, the polymerizer capsule 30 may be provided along the left and right ends of the electrode body 21. In particular, when the wound electrode body 21 is employed, the electrode body 21 and the case 11 are equal to the thickness (plate thickness) in the left-right direction of each of the current collecting terminals 17 and 18 and the R portion of the corner portion 11a. A gap 11b is formed between the inner wall surface and the inner wall surface. In this example, the dead space generated in the case 11 can be effectively utilized by disposing the polymerizer capsule 30 in the gap 11b. That is, the polymerizer capsule 30 can be disposed without reducing the volume energy density of the secondary battery 10. Further, the polymer capsule 30 may be disposed along the bottom of the case 11 (main body member 12).

The shape of the polymer capsule 30 may be changed as appropriate, such as a columnar shape or a cubic shape.
The resin film 30a may be formed using polyethylene having a different melting point (for example, 90 ° C. to 130 ° C.) as long as the melting point is lower than the thermal runaway temperature of the secondary battery 10. However, since it is advantageous to release the non-polymerized polymer agent 31 to gel the non-aqueous electrolyte, it is preferable to configure as in the above embodiment.

If the resin film 30a is chemically stable with respect to the nonaqueous electrolyte and has a melting point lower than the thermal runaway temperature of the secondary battery 10, the type of the resin material can be changed as appropriate.
A Ti alkoxide (titanium alkoxide) may be used as the polymerization agent 31. In this case, the Ti alkoxide may be encapsulated in the polymerizer capsule 30 as a solid, or may be encapsulated in the polymerizer capsule 30 in a state dissolved in an organic solvent. According to this, the non-aqueous electrolyte filled in the case 11 can be polymerized and gelled.

The active material layer 26 may be formed by applying the active material only to one side of the positive electrode sheet 24 and the negative electrode sheet 25.
(Circle) you may change suitably the number of the positive electrode sheet 24 which comprises the electrode body 21, and the negative electrode sheet 25. FIG. For example, the electrode body 21 including one positive electrode sheet 24 and one negative electrode sheet 25 may be used.

The shape of the case 11 may be formed in a columnar shape or an elliptical column shape that is flat in the left-right direction.
○ The secondary battery 10 of the above embodiment is mounted on a vehicle (for example, an industrial vehicle or a passenger vehicle), and is charged by a generator mounted on the vehicle, while the compressor for an air conditioner is supplied with electric power supplied from the secondary battery 10 Alternatively, an electric motor for driving the wheels or an electrical component such as a car navigation system may be driven. According to this, by suppressing generation | occurrence | production of thermal runaway, while being able to improve the safety as a vehicle, the volume energy density of the secondary battery 10 is improved by setting battery voltage high, and secondary The battery 10 can be reduced in size and capacity. For example, when the capacity of the secondary battery 10 is increased, the amount of power (usage time) that can be used by one full charge in the vehicle can be improved. In particular, when the electric motor is driven by the power supplied from the secondary battery 10, the total travel distance that can be traveled with one full charge can be increased. Further, when the secondary battery 10 is downsized, the degree of freedom of the location where the secondary battery 10 is installed in the vehicle can be improved.

  (Circle) you may arrange | position the polymerizer capsule 30 in the case of the nonaqueous electrolyte capacitor (nonaqueous electrolyte capacitor) as an electrical storage apparatus, for example. In this case, a power storage device having an electrode body in which the electrodes are layered and a non-aqueous electrolyte in which an electrolyte salt is dissolved in a non-aqueous solvent, and a polymerization agent that gels the non-aqueous electrolyte by a polymerization reaction; The separator may be made of a material having a melting point lower than the thermal runaway temperature, and a separating member that isolates the polymerization agent from the nonaqueous electrolyte and the electrode body.

  DESCRIPTION OF SYMBOLS 10 ... Lithium ion secondary battery (nonaqueous electrolyte secondary battery), 11 ... Case, 21 ... Electrode body, 24 ... Positive electrode sheet (electrode), 25 ... Negative electrode sheet (electrode), 26 ... Active material layer, 30 ... polymerization agent capsule, 30a ... resin film (isolation member, film), 31 ... polymerization agent.

Claims (7)

An electrode body in which an electrode in which an active material layer is formed has a layer shape, and a nonaqueous electrolyte secondary battery in which a nonaqueous electrolyte in which an electrolyte salt is dissolved in a nonaqueous solvent is contained in a case,
A polymerizing agent that gels the non-aqueous electrolyte by a polymerization reaction;
An isolation member made of a material having a melting point lower than a thermal runaway temperature, and isolating the polymerization agent from the nonaqueous electrolyte and the electrode in the case;
The non-aqueous electrolyte secondary battery, wherein the polymerizing agent is a Ti alkoxide . The non-aqueous electrolyte secondary battery according to claim 1 , wherein the separating member includes the polymerizing agent and is disposed between the electrode body and the case. A current collecting terminal is fixed to an end of the electrode body,
The non-aqueous electrolyte secondary battery according to claim 2 , wherein the separating member is disposed along an end of the electrode body on a side where the current collecting terminal is fixed . The electrode body is formed by winding an electrode sheet having a long sheet shape,
The non-aqueous electrolyte secondary battery according to claim 1, wherein the isolation member is disposed at the center of the electrode body.   The non-aqueous electrolyte secondary battery according to claim 1, wherein the isolation member is a film made of polyethylene.   A vehicle comprising the nonaqueous electrolyte secondary battery according to any one of claims 1 to 5. A power storage device having an electrode body in which an electrode is layered and a non-aqueous electrolyte in which an electrolyte salt is dissolved in a non-aqueous solvent,
A polymerizing agent that gels the non-aqueous electrolyte by a polymerization reaction;
An isolation member made of a material having a melting point lower than the thermal runaway temperature, and isolating the polymerizer from the non-aqueous electrolyte and the electrode body,
The power storage device, wherein the polymerization agent is Ti alkoxide .