Battery and method for manufacturing the same

Abstract

To provide a technique of accommodating a power generation element and a collector in a storage body in a desirable state.SOLUTION: A battery includes: an insulating storage body with a recessed storage unit; a semi-solid power generation element including an electrolyte stored in the storage unit; and a collector between the inner surface of the storage unit and the power generation element.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a battery and a method for manufacturing the same. [Background technology]

[0002] A battery is disclosed in Patent Document 1. The battery in Patent Document 1 includes an insulating container having a recessed housing portion, and a power generating element housed in the housing portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2014 / 112395 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, it is unclear in what state the power generating element and current collector of the battery are housed in the housing. However, in order to improve the performance of the battery, it is important to know in what state the power generating element and current collector are housed in the housing. This specification provides a technology that can house the power generating element and current collector in the housing in good condition. [Means for solving the problem]

[0005] In a first aspect of the present technology, a battery includes an insulating container having a concave storage portion, a semi-solid power generating element containing an electrolyte solution stored in the storage portion, and a current collector disposed between the inner surface of the storage portion and the power generating element.

[0006] This configuration improves the adhesion between the power generating element and the current collector housed in the housing portion of the housing, allowing the power generating element and the current collector to be housed in the housing in good condition, thereby improving the performance of the battery.

[0007] In a second aspect, in the first aspect, the current collector may be adhered to the inner surface of the housing with an adhesive. This configuration makes it possible to prevent the current collector from shifting position or from wrinkling.

[0008] In a third aspect, in the first or second aspect, the inner bottom surface of the housing portion may have an inclined surface that slopes downward from the center toward the periphery. With this configuration, the power generating element can be accommodated evenly throughout the housing portion.

[0009] In a fourth aspect, in any one of the first to third aspects, an uneven portion may be provided on at least a part of the inner circumferential surface of the storage portion.

[0010] With this configuration, gas generated from the power generating element (for example, gas generated during the degassing process of the power generating element) can be smoothly discharged to the outside of the housing.

[0011] In a fifth aspect, in the fourth aspect, the concave-convex portion may be made of a heat-shrinkable material. With this configuration, the concave-convex portion becomes flat by heat shrinkage, thereby increasing the amount of power generating element per unit volume of the housing portion.

[0012] In a sixth aspect of the present technology, a battery includes an insulating container having a concave housing portion, a semi-solid power generating element containing an electrolyte solution housed in the housing portion, and a current collector disposed between the inner surface of the housing portion and the power generating element. A method for manufacturing this battery includes a step of pressing the power generating element housed in the housing portion toward the inner surface of the housing portion.

[0013] This configuration improves the adhesion between the power generating element and the current collector housed in the housing portion of the housing, allowing the power generating element and the current collector to be housed in the housing in good condition, thereby improving the performance of the battery. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 2 is a top view of the battery of Example 1. [Figure 2] Cross-sectional view of II-II in Figure 1. [Figure 3] Cross-sectional view of FIG. 1 taken along line III-III. [Figure 4] 3A to 3C are diagrams illustrating a method for manufacturing a battery according to the first embodiment. [Figure 5] FIG. 10 is a cross-sectional view showing a partial exploded configuration of a battery according to a second embodiment. [Figure 6] FIG. 10 is a cross-sectional view showing a partial exploded configuration of a battery according to a third embodiment. [Figure 7] FIG. 10 is a cross-sectional view showing a partial exploded configuration of the battery of Example 4. [Figure 8] Cross-sectional view of VIII-VIII in Figure 7. DETAILED DESCRIPTION OF THE INVENTION

[0015] Example 1 A battery 2 of Example 1 will be described with reference to the drawings. As shown in Figures 1 to 3, the battery 2 of Example 1 includes an insulating positive electrode housing 10, an insulating negative electrode housing 20, and a separator 70 disposed between the positive electrode housing 10 and the negative electrode housing 20. The battery 2 also includes a positive electrode current collector 30 and a positive electrode power generating element 50 housed in the positive electrode housing 10, and a negative electrode current collector 40 and a negative electrode power generating element 60 housed in the negative electrode housing 20.

[0016] The positive electrode container 10 includes a recessed container portion 12 and a peripheral portion 16 provided around the container portion 12. The peripheral portion 16 protrudes laterally from the upper end of the container portion 12.

[0017] The positive electrode container 10 is produced, for example, by processing an insulating substrate 100. The insulating substrate 100 is made of, for example, a film having a three-layer structure. The substrate 100 of this example includes, in order from the inside of the positive electrode container 10, a first layer 101, a second layer 102, and a third layer 103.

[0018] The first layer 101 and the third layer 103 of the substrate 100 are insulating. The first layer 101 constitutes the inner surface of the positive electrode container 10. The third layer 103 constitutes the outer surface of the positive electrode container 10. The first layer 101 and the third layer 103 are made of a material containing one or more components selected from, for example, polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyvinyl chloride, silicone rubber, and fluororesin (e.g., polytetrafluoroethylene, perfluoroalkoxyalkane, etc.). The first layer 101 and the third layer 103 may be made of the same material or different materials.

[0019] The second layer 102 of the substrate 100 is disposed between the first layer 101 and the third layer 103. The second layer 102 is made of a metal such as aluminum.

[0020] Next, the positive electrode current collector 30 and the positive electrode power generating element 50 housed in the positive electrode housing 10 will be described. The positive electrode current collector 30 is a sheet-like member having electrical conductivity. The positive electrode current collector 30 is formed of, for example, a metal foil made of aluminum. The current collecting portion 32 on the positive electrode side of the battery 2 includes the positive electrode current collector 30 arranged along the inner surface 14 of the housing portion 12 of the positive electrode housing 10, and a terminal portion 36 arranged along the peripheral portion 16 of the positive electrode housing 10. The positive electrode current collector 30 is arranged along part or all of the inner bottom surface 142 and the inner circumferential surface 144 of the housing portion 12. The positive electrode current collector 30 is arranged between the inner surface 14 of the housing portion 12 and the positive electrode power generating element 50.

[0021] The terminal portion 36 extends from the inside to the outside of the positive electrode housing 10. The terminal portion 36 is drawn out and exposed to the outside of the positive electrode housing 10. The terminal portion 36 is sandwiched between the peripheral edge portion 16 of the positive electrode housing 10 and the separator 70.

[0022] The positive electrode power generating element 50 is filled between the positive electrode container 10 and the separator 70. The positive electrode power generating element 50 is filled between the positive electrode current collector 30 of the current collecting portion 32 and the separator 70.

[0023] The positive electrode power generating element 50 includes a positive electrode mixture and an electrolyte. The positive electrode power generating element 50 is, for example, in a state in which the positive electrode mixture is mixed with the electrolyte. The positive electrode power generating element 50 is housed in the housing portion 12 of the positive electrode housing 10 in a semi-solid state (for example, a gel, slurry, or clay state).

[0024] The types of the positive electrode mixture and the electrolyte are not particularly limited. The positive electrode mixture and the electrolyte are, for example, a positive electrode mixture and an electrolyte for a lithium ion secondary battery. The positive electrode mixture includes, for example, a positive electrode active material for a lithium ion secondary battery. The positive electrode active material for a lithium ion secondary battery includes, for example, a lithium-containing metal oxide. The positive electrode mixture may include an additive in addition to the positive electrode active material.

[0025] Next, the configuration of the negative electrode side of the battery 2 will be described. The configuration of the negative electrode side of the battery 2 is the same as that of the positive electrode side described above, so a detailed description may be omitted. The negative electrode container 20 includes a recessed container portion 22 and a peripheral portion 26 provided around the container portion 22. The peripheral portion 26 protrudes laterally from the upper end (lower end in FIG. 2 ) of the container portion 22.

[0026] The negative electrode container 20 is produced, for example, by processing an insulating substrate 100. The insulating substrate 100 is made of, for example, a film with a three-layer structure. The substrate 100 includes, in order from the inside of the negative electrode container 20, a first layer 101, a second layer 102, and a third layer 103. The configuration of the substrate 100 is as described above.

[0027] The negative electrode current collector 40 is a sheet-like member having electrical conductivity. The negative electrode current collector 40 is formed of, for example, a metal foil made of copper. The current collector 42 on the negative electrode side of the battery 2 includes the negative electrode current collector 40 arranged along the inner surface 24 of the housing portion 22 of the negative electrode housing 20, and a terminal portion 46 arranged along the peripheral portion 26 of the negative electrode housing 20. The negative electrode current collector 40 is arranged along part or all of the inner bottom surface 242 and the inner circumferential surface 244 of the housing portion 22. The negative electrode current collector 40 is arranged between the inner surface 24 of the housing portion 22 and the negative electrode power generating element 60.

[0028] The terminal portion 46 extends from the inside to the outside of the negative electrode housing body 20. The terminal portion 46 is drawn out and exposed to the outside of the negative electrode housing body 20. The terminal portion 46 is sandwiched between the peripheral edge portion 26 of the negative electrode housing body 20 and the separator 70.

[0029] The negative electrode power generating element 60 is filled between the negative electrode container 20 and the separator 70. The negative electrode power generating element 60 is filled between the negative electrode current collector 40 of the current collecting portion 42 and the separator 70.

[0030] The negative electrode power generating element 60 includes a negative electrode mixture and an electrolyte solution. The negative electrode power generating element 60 is, for example, in a state in which the negative electrode mixture is mixed with the electrolyte solution. The negative electrode power generating element 60 is accommodated in the accommodation portion 22 of the negative electrode accommodation body 20 in a semi-solid state (for example, a gel, slurry, or clay state).

[0031] The types of the negative electrode mixture and the electrolyte are not particularly limited. The negative electrode mixture and the electrolyte are, for example, those for lithium ion secondary batteries. The negative electrode mixture includes, for example, a negative electrode active material for lithium ion secondary batteries. The negative electrode active material for lithium ion secondary batteries includes, for example, carbon. The negative electrode mixture may include additives in addition to the negative electrode active material.

[0032] The positive electrode container 10 and the negative electrode container 20 of the battery 2 are combined with each other in a state where the container sections 12, 22 face each other. A separator 70 is sandwiched between the positive electrode container 10 and the negative electrode container 20.

[0033] The separator 70 is sandwiched between the peripheral edge portion 16 of the positive electrode housing body 10 and the peripheral edge portion 26 of the negative electrode housing body 20. The peripheral edge portion 16 of the positive electrode housing body 10 and the peripheral edge portion 26 of the negative electrode housing body 20 are bonded to the separator 70 by, for example, thermocompression bonding.

[0034] The separator 70 is made of, for example, an ion exchanger having an ion exchange function. The ion exchanger is a substance containing one or more components selected from, for example, polyolefin, polyester, cellulose, ceramic, and graphene. The ion exchanger may also be Nafion (registered trademark).

[0035] (Manufacturing method of battery 2) Next, a method for manufacturing the battery 2 of Example 1 will be described. In the method for manufacturing the battery 2, as shown in Fig. 4, the positive electrode current collector 30 is arranged along the inner surface 14 of the positive electrode housing 10. Next, the positive electrode power generating element 50 is arranged in the housing portion 12 of the positive electrode housing 10. The amount of the positive electrode power generating element 50 is adjusted according to the capacity of the housing portion 12.

[0036] Next, the positive electrode power generating element 50 housed in the housing portion 12 is pressed against the inner surface 14 of the housing portion 12. This allows the positive electrode power generating element 50 to be molded to fit the shape of the housing portion 12. In a modified example, a separator 70 may be placed on the positive electrode power generating element 50, and then the positive electrode power generating element 50 may be pressed via the separator 70. The same steps as for the positive electrode housing portion 10 are also performed for the negative electrode housing 20.

[0037] Next, a separator 70 is placed between the positive electrode container 10 and the positive electrode power generating element 50 and the negative electrode container 20 and the negative electrode power generating element 60. Then, the positive electrode container 10 and the negative electrode container 20 are joined via the separator 70. In this manner, the battery 2 can be manufactured.

[0038] (effect) The above has described the battery 2 of Example 1. As is clear from the above description, the battery 2 includes an insulating positive electrode housing 10 having a concave housing portion 12, a semi-solid positive electrode power generating element 50 containing an electrolyte solution housed in the housing portion 12, and a positive electrode current collector 30 disposed between the inner surface 14 of the housing portion 12 and the positive electrode power generating element 50.

[0039] This configuration can improve the adhesion between the positive electrode power generating element 50 and the positive electrode current collector 30 housed in the housing portion 12 of the positive electrode housing 10, allowing the positive electrode power generating element 50 and the positive electrode current collector 30 to be housed in a good condition in the positive electrode housing 10. The same applies to the configuration on the negative electrode side. This can improve the performance of the battery 2.

[0040] The manufacturing method of the battery 2 also includes a step of applying pressure to the positive electrode power generating element 50 housed in the housing portion 12 of the positive electrode housing body 10 toward the inner surface 14 of the housing portion 12. This configuration can improve the adhesion between the positive electrode power generating element 50 housed in the housing portion 12 of the positive electrode housing body 10 and the positive electrode current collector 30.

[0041] Although the first embodiment has been described above, the configuration of the battery 2 is not limited to the above embodiment. In the following description, detailed description of the same configuration as that described above may be omitted.

[0042] Example 2 In Example 2, as shown in Fig. 5 , the positive electrode current collector 30 is adhered to the inner surface 14 of the housing portion 12 of the positive electrode housing body 10. For example, the positive electrode current collector 30 is adhered to the inner bottom surface 142 of the housing portion 12 with an insulating adhesive 80. In a modified example, the positive electrode current collector 30 may be adhered to the inner bottom surface 142 and the inner circumferential surface 144 of the housing portion 12. The negative electrode current collector 40 may also have a configuration similar to that of the positive electrode current collector 30.

[0043] The above configuration can prevent the positive electrode current collector 30 from shifting position and from wrinkling. The same applies to the configuration on the negative electrode side.

[0044] Example 3 In Example 3, as shown in FIG. 6 , the inner bottom surface 142 of the housing portion 12 of the positive electrode housing 10 has an inclined surface 146 that slopes downward from the center toward the periphery. The inclined surface 146 extends linearly in a cross-sectional view. In a modified example, the inclined surface 146 may extend in a curved shape in a cross-sectional view. For example, the inclined surface 146 may be a convexly curved curve or a concavely curved curve. The negative electrode housing 20 may also have a configuration similar to that of the positive electrode housing 10.

[0045] With the above-described configuration, the positive electrode power generating element 50 can be accommodated evenly throughout the entire accommodating portion 12. The same applies to the configuration on the negative electrode side.

[0046] Example 4 In Example 4, as shown in Figs. 7 and 8, an uneven portion 90 is provided on the inner circumferential surface 144 of the housing portion 12 of the positive electrode housing body 10. The uneven portion 90 on the inner circumferential surface 144 of the housing portion 12 is provided over the entire periphery of the inner circumferential surface 144 of the housing portion 12. In a modified example, the uneven portion 90 may be provided on only a portion of the inner circumferential surface 144 of the housing portion 12. It is sufficient that the uneven portion 90 on the inner circumferential surface 144 is provided on at least a portion of the inner circumferential surface 144 of the housing portion 12. The negative electrode housing body 20 may also have a configuration similar to that of the positive electrode housing body 10.

[0047] The uneven portion 90 provided on the inner circumferential surface 144 of the storage portion 12 is made of, for example, a heat-shrinkable material. For example, the uneven portion 90 is made of a material containing one or more components selected from polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyvinyl chloride, silicone rubber, and fluororesin (e.g., polytetrafluoroethylene, perfluoroalkoxyalkane, etc.). Note that portions other than the uneven portion 90 may also be made of a heat-shrinkable material. Alternatively, portions other than the uneven portion 90 may be made of a non-heat-shrinkable material.

[0048] With the above configuration, gas generated from the positive electrode power generating element 50 (for example, gas generated during a degassing process for the positive electrode power generating element 50) can be smoothly discharged to the outside of the positive electrode housing 10. Furthermore, the uneven portion 90 becomes flat due to thermal contraction, causing the housing portion 12 to contract, thereby increasing the density of the positive electrode power generating element 50 per unit volume. The same applies to the configuration on the negative electrode side.

[0049] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives is itself technically useful. [Explanation of symbols]

[0050] 2: battery, 10: positive electrode container, 20: negative electrode container, 30: positive electrode current collector, 40: negative electrode current collector, 50: positive electrode power generating element, 60: negative electrode power generating element, 70: separator, 80: adhesive, 90: uneven portion, 100: substrate, 101: first layer, 102: second layer, 103: third layer

Claims

1. an insulating container having a recessed container portion; a semi-solid power generating element containing an electrolytic solution contained in the container; a current collector disposed between the inner surface of the housing portion and the power generating element.

2. 10. The battery of claim 1, The battery, wherein the current collector is adhered to the inner surface of the housing portion with an adhesive.

3. 3. The battery according to claim 1 or 2, The battery, wherein the inner bottom surface of the storage section has an inclined surface that slopes downward from the center toward the periphery.

4. 3. The battery according to claim 1 or 2, The battery has an uneven portion provided on at least a part of the inner circumferential surface of the housing portion.

5. 5. The battery of claim 4, The battery, wherein the uneven portion is made of a heat-shrinkable material.

6. an insulating container having a recessed container portion; a semi-solid power generating element containing an electrolytic solution housed in the housing; a current collector disposed between the inner surface of the housing portion and the power generating element, The manufacturing method includes a step of applying pressure to the power generating element housed in the housing portion toward an inner surface of the housing portion.

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