Cushioning material for battery

Abstract

This cushioning material for a battery has a sheet shape. The cushioning material for a battery includes a plurality of protrusions 110 protruding to one side in the sheet thickness direction, and a base 120 connecting the plurality of protrusions 110. The base 120 has an easily deformable part 122 between adjacent protrusions 110.

Description

Buffer material for battery

[0001] The present invention relates to a buffer material for a battery.

[0002] There is known a buffer material for a battery that elastically relaxes a load in a battery. For example, a buffer material for a battery disposed between a case that houses a stack of battery cells serving as a power generation source and a housing (restraint) that holds the case by sandwiching it is a typical example (for example, Patent Document 1). By disposing the buffer material for the battery, it is possible to secure the load necessary to hold the stack of battery cells while relaxing an excessive load.

[0003] Japanese Patent Application Laid-Open No. 2017-152338

[0004] The buffer material for a battery described in Patent Document 1 includes a plurality of protrusions protruding from one side in the sheet thickness direction. Such a buffer material for a battery relaxes the load by the plurality of protrusions being crushed and compressed. However, when the protrusions are compressed, they spread, and their deformation may have an adverse effect on adjacent protrusions. For example, when a certain protrusion spreads, an adjacent protrusion may fall down, or an adjacent protrusion may be pushed and its position may shift. In this case, the buffer material cannot generate a reaction force as designed.

[0005] The present invention has been made in view of such a situation, and an exemplary object of one aspect thereof is to provide a technique capable of reducing the influence of the deformation of a certain protrusion on adjacent protrusions in a battery buffer material including a plurality of protrusions.

[0006] In order to solve the above problems, a buffer material for a battery according to an aspect of the present invention is a sheet-like buffer material for a battery, and includes a plurality of protrusions protruding from one side in the sheet thickness direction and a base portion connecting the plurality of protrusions. The base portion has an easily deformable portion between adjacent protrusions.

[0007] Another aspect of the present invention is a battery cushioning material. This battery cushioning material is a sheet-like battery cushioning material comprising a plurality of protrusions projecting from one side in the thickness direction of the sheet, and a base portion connecting the plurality of protrusions. The base portion has thin sections between adjacent protrusions.

[0008] Yet another aspect of the present invention is also a battery cushioning material. This battery cushioning material is a sheet-like battery cushioning material comprising a plurality of protrusions projecting from one side in the thickness direction of the sheet, and a base portion connecting the plurality of protrusions. The base portion has a wave-shaped portion between adjacent protrusions.

[0009] According to the present invention, in a battery cushioning material having multiple protrusions, it is possible to provide a technology that can reduce the effect of deformation of one protrusion on an adjacent protrusion.

[0010] This figure shows a battery equipped with a cushioning material according to an embodiment. This is a perspective view of the cushioning material in Figure 1. This is a plan view of the cushioning material in Figure 1. Figures 4(a) and 4(b) are cross-sectional views taken along line A-A in Figure 3. Figures 5(a) and 5(b) are cross-sectional views showing a modified cushioning material. Figures 6(a) and 6(b) are cross-sectional views showing a modified cushioning material. Figures 7(a) and 7(b) are cross-sectional views showing a modified cushioning material.

[0011] The present invention will be described below with reference to the drawings, based on preferred embodiments. The embodiments are illustrative and not limiting, and not all features or combinations thereof described in the embodiments are necessarily essential to the invention. The same or equivalent components, members, and processes shown in each drawing will be denoted by the same reference numerals, and redundant explanations will be omitted as appropriate.

[0012] Figure 1 is a cross-sectional view showing the configuration of a battery 1 equipped with a cushioning material 100 according to an embodiment. The battery 1 is a secondary battery such as a lithium-ion battery. The battery 1 comprises a laminate 10, a case 20, a restraint 30, and a cushioning material 100.

[0013] The laminate 10 is a laminate formed by stacking multiple battery cells.

[0014] Case 20 is a hollow member that houses the laminate 10. In this example, case 20 is formed in the shape of a hollow rectangular parallelepiped. For example, case 20 is made of metal, i.e., a can case. Both end faces of the laminate 10 in the stacking direction D are in contact with the inner side surfaces of case 20.

[0015] The restraint device 30 is a member that restrains the laminate 10 together with the case 20. The restraint device 30 restrains the case 20 from both sides in the stacking direction D of the laminate 10. The restraint device 30 clamps the case 20 from both sides in the stacking direction D via the cushioning material 100 and presses both end faces of the case 20 in the stacking direction D.

[0016] The cushioning material 100 is placed between the case 20 and the restraint 30. Alternatively, the cushioning material 100 may be placed between the laminate 10 and the case 20. Or, if the battery cells are, for example, rectangular battery cells, the cushioning material 100 may be placed between the battery cells. In any case, the cushioning material 100 is placed between the components of the battery 1. In other words, the cushioning material 100 is a cushioning material for a battery.

[0017] The cushioning material 100 may be used individually as shown in the figure, but it may also be used by stacking multiple pieces together, or by arranging multiple pieces on a flat surface.

[0018] Figure 2 is a perspective view of the cushioning material 100. Figure 3 is a plan view of the cushioning material 100, in other words, a view of the cushioning material 100 in the direction of the sheet thickness. Figures 4(a) and 4(b) are cross-sectional views taken along line A-A in Figure 3. That is, Figures 4(a) and 4(b) are cross-sectional views of the cushioning material 100 cut along a plane perpendicular to the longitudinal direction of the projection 110. Figure 4(a) shows the state in which no load is applied to the cushioning material 100, and Figure 4(b) shows the state in which a load is applied to the cushioning material 100.

[0019] In Figures 3 and 4, the z-direction is the thickness direction of the cushioning material 100 sheet. The z-direction can also be considered as the thickness direction of the base portion 120 (described later) of the cushioning material 100. The x-direction and y-direction are perpendicular to the z-direction. The x-direction and y-direction are perpendicular to each other. The x-direction and y-direction can also be considered as the plane direction of the base portion 120.

[0020] The cushioning material 100 is in the form of a sheet. The cushioning material 100 exhibits a cushioning effect against loads acting in the sheet thickness direction (z direction). The planar shape and planar size of the cushioning material 100 are not particularly limited. The cushioning material 100 is made of an elastic material such as rubber or elastomer. In other words, the cushioning material 100 is an elastically deformable component.

[0021] The cushioning material 100 has a plurality of protrusions 110 that project outwards from one side in the sheet thickness direction, and a planar base 120 that connects the plurality of protrusions 110.

[0022] The arrangement of the multiple protrusions 110 is not particularly limited, but in the illustrated example, some of the protrusions 110 extend in the x direction and are aligned in the y direction. The remaining protrusions 110 extend in the y direction and are aligned in the x direction. Alternatively, all of the protrusions 110 may be arranged to extend in the same direction (for example, the x direction).

[0023] In this embodiment, the projection 110 is formed to be hollow, and its hollow portion 110a opens to the other side in the sheet thickness direction.

[0024] In this example, the projection 110 has a tapered mountain shape in a cross-section perpendicular to its longitudinal direction. However, the shape of the projection 110 is not limited to this. For example, the projection 110 may have a flat top in the cross-section. Alternatively, the projection 110 may have a tapered shape only at its top in the cross-section.

[0025] The base portion 120 has easily deformable portions 122 between adjacent projections 110. The space between adjacent projections 110 may be between adjacent projections 110 extending in the same direction, or between adjacent projections 110 extending in different directions, i.e., between a projection 110 extending in the x direction and a projection 110 extending in the y direction. In the illustrated example, the easily deformable portions 122 are provided in both of these cases.

[0026] Preferably, the easily deformable portion 112, which is provided adjacent to the projection 110 along the direction of extension of the projection 110, extends for a length equal to or greater than that of the projection 110.

[0027] In this embodiment, the easily deformable portion 122 is a portion that is more easily deformed than the projection portion 110. More specifically, the easily deformable portion 122 is a thin-walled portion that is thinner than the projection portion 110.

[0028] As shown in the illustrated example, only a portion of the base portion 120 between adjacent protrusions 110, such as the central portion in the direction adjacent to the protrusions 110 (left-right direction on the paper), may be the easily deformable portion (thin-walled portion) 122. Alternatively, unlike the illustrated example, the entire portion of the base portion 120 between adjacent protrusions 110 may be the easily deformable portion (thin-walled portion) 122.

[0029] According to this embodiment, since the base portion 120 has a deformable portion 122 between adjacent protrusions 110, when a load is applied to the cushioning material 100, as shown in Figure 4(b), when the protrusions 110 deform so that their roots spread out, the deformable portion 122 deforms so that it folds (i.e., shrinks) in a wave-like shape, for example, thus reducing or eliminating the effect of the deformation of one protrusion 110 on the adjacent protrusions 110. As a result, the protrusions 110 can be prevented from falling over.

[0030] The present invention has been described above based on embodiments. These embodiments are illustrative, and it will be understood by those skilled in the art that various modifications are possible in combinations of these components and processing processes, and that such modifications also fall within the scope of the present invention. These modifications will now be described.

[0031] (Modification 1) In the embodiment, the case in which the easily deformable portion 122 of the cushioning material 100 is a thin-walled portion was described, but the easily deformable portion 122 is not limited to a thin-walled portion as long as it is more easily deformable than the protrusion portion 110. For example, the easily deformable portion 122 may be a wave-shaped portion having a corrugated cross-section. Alternatively, the easily deformable portion 122 may be a flexible material portion formed from a material more flexible than the protrusion portion 110. Or, the easily deformable portion 122 may be a combination of at least two of the thin-walled portion, the wave-shaped portion, and the flexible material portion. According to these modifications, the same effects as in the embodiment can be achieved. Specific examples will be described below.

[0032] Figures 5(a) and 5(b) are cross-sectional views showing modified cushioning materials. Figures 5(a) and 5(b) correspond to Figures 4(a) and 4(b), respectively. In this modified example, the easily deformable portion 122 is a thin-walled and corrugated portion. When the easily deformable portion 122 is a corrugated portion, it can not only shrink but also stretch, thus providing high flexibility. As shown in the illustrated example, only a portion of the base portion 120 between adjacent protrusions 110, such as the central portion in the direction adjacent to the protrusions 110 (left-right direction of the paper), may be the easily deformable portion 122, or, unlike the illustrated example, the entire portion of the base portion 120 between adjacent protrusions 110 may be the easily deformable portion 122.

[0033] (Modification 2) In the embodiment and the above-described modification, the case in which the projection 110 of the cushioning material 100 is hollow was described, but the projection 110 may be solid. In this case as well, the easily deformable portion 122 may be a thin-walled portion, a corrugated portion, or a flexible material portion. Alternatively, the easily deformable portion 122 may be a combination of at least two of the thin-walled portion, the corrugated portion, and the flexible material portion.

[0034] Figures 6(a) and 6(b) are cross-sectional views showing modified cushioning materials. Figures 6(a) and 6(b) correspond to Figures 4(a) and 4(b), respectively. In this modified example, the easily deformable portion 122 is a thin-walled portion. In this case, as shown in the illustrated example, only a portion of the base portion 120 between adjacent protrusions 110, such as the central portion in the direction adjacent to the protrusions 110 (left-right direction on the paper), is the easily deformable portion 122, i.e., the thin-walled portion, and is formed to be thinner than the other portions which are the non-easily deformable portion 124.

[0035] Figures 7(a) and 7(b) are cross-sectional views showing a cushioning material according to another modified example. Figure 7(b) shows the cushioning material 100 under load. In this modified example, the easily deformable portion 122 is a thin-walled portion and a corrugated portion.

[0036] According to this modified example, since the base portion 120 has a deformable portion 122 between adjacent protrusions 110, when a load is applied to a protrusion 110, as shown in Figures 6(b) and 7(b), when the protrusion 110 deforms by collapsing and spreading, the deformable portion 122 deforms by folding (i.e., shrinking) in a wave-like shape, for example. This reduces or eliminates the effect of the deformation of one protrusion 110 on the adjacent protrusion 110. As a result, it is possible to avoid the protrusion 110 being pushed by the adjacent protrusion 110 and shifting its position.

[0037] (Modification 3) In the embodiment and the above-described modification, the case in which the cushioning material 100 is a battery cushioning material has been described, but the use of the cushioning material 100 is not limited to this. For example, the cushioning material may be used as a cushioning material to alleviate the load acting on the substrate of an electronic component.

[0038] The embodiments and modifications described above are illustrative. The technical ideas abstracted from them should not be interpreted as being limited to the content of the embodiments and modifications. Many design changes, such as modifications, additions, and deletions of components, are possible in the embodiments and modifications.

[0039] This invention relates to a buffer material for batteries.

[0040] DESCRIPTION OF SYMBOLS 100 Cushioning material, 110 Projection part, 110a Hollow part, 120 Base.

Claims

1. A sheet-shaped battery cushioning material comprising: a plurality of protrusions projecting from one side in the thickness direction of the sheet; and a base connecting the plurality of protrusions, wherein the base has easily deformable portions between adjacent protrusions.

2. The battery cushioning material according to claim 1, wherein the projection is formed to be hollow, and the easily deformable portion is a thin-walled portion that is thinner than the projection.

3. The battery cushioning material according to claim 1, wherein the projection is formed solid, and the easily deformable portion is a thin-walled portion that is thinner than the non-deformable portion of the base between adjacent projections.

4. The battery cushioning material according to claim 1 or 2, wherein the easily deformable portion is a corrugated portion.

5. A sheet-shaped battery cushioning material comprising: a plurality of protrusions projecting from one side in the thickness direction of the sheet; and a base connecting the plurality of protrusions, wherein the base has thin sections between adjacent protrusions.

6. A sheet-shaped battery cushioning material comprising: a plurality of protrusions projecting from one side in the thickness direction of the sheet; and a base connecting the plurality of protrusions, wherein the base has a wave-shaped portion between adjacent protrusions.

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