Energy storage cells and energy storage devices

Abstract

To obtain a power storage cell in which the insulating film can be easily removed from the cell body. [Solution] The energy storage cell 20 comprises a cylindrical cell body 22 and an insulating film 24 that covers the outer surface of the cell body 22 and has an easily breakable portion 28.

Description

Technical Field

[0001] The present invention relates to a storage battery cell and a storage battery device.

Background Art

[0002] Patent Document 1 below discloses a battery (storage battery cell) in which the outer peripheral surface of a columnar battery body (cell body) is covered with an exterior film (insulating film).

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above prior art, it is difficult to remove the insulating film from the cell body during disassembly such as recycling of the storage battery cell.

[0005] An object of the present invention is to obtain a storage battery cell in which the insulating film can be easily removed from the cell body and a storage battery device including the storage battery cell.

Means for Solving the Problems

[0006] The storage battery cell according to the first aspect includes a columnar cell body and an insulating film that covers the outer peripheral surface of the cell body and has an easily breakable portion that is easily broken.

[0007] In the first aspect, the outer peripheral surface of the columnar cell body is covered with an insulating film. The insulating film has an easily breakable portion that is easily broken. By breaking the insulating film at this easily breakable portion, the insulating film can be easily removed from the cell body.

[0008] Furthermore, the "easily breakable portion" described in the first embodiment only needs to be configured such that the insulating film can be broken at that location when an external force is applied. This may involve locally forming holes in the insulating film or reducing its thickness to weaken it, or it may be any other configuration.

[0009] In the second embodiment of the energy storage cell, the easily breakable portion extends in the circumferential direction of the cell body, as in the first embodiment.

[0010] In the second embodiment, since the easily breakable portion extends in the circumferential direction of the cell body, the insulating film can be easily removed from the cell body while suppressing a decrease in the insulating properties of the insulating film.

[0011] In the third embodiment of the energy storage cell, in the second embodiment, the easily breakable portion has a thin-walled portion in which the thickness of the insulating film is locally reduced.

[0012] In the third embodiment, since the easily breakable portion has the thin-walled portion described above, the insulating film can be easily broken starting from the thin-walled portion. Note that the above-mentioned "locally thinned" includes configurations in which the thickness is locally zero.

[0013] In the fourth embodiment of the energy storage cell, the thin-walled portion extends in an annular shape continuously in the circumferential direction of the cell body, as in the third embodiment.

[0014] In the fourth embodiment, since the thinned portion of the insulating film extends continuously in an annular shape around the circumferential direction of the cell body, the insulating film can be removed from the cell body more easily (with less force).

[0015] The fifth embodiment of the energy storage cell is such that, in any one of the first to fourth embodiments, the cell body has a recess on its outer surface, and the easily breakable portion is provided in the insulating film on the portion opposite to the recess.

[0016] In the fifth embodiment, the insulating film is provided with an easily breakable portion in the portion facing the recess provided on the outer surface of the cell body, thereby suppressing a decrease in insulating properties due to the provision of an easily breakable portion in the insulating film.

[0017] In the sixth embodiment of the energy storage cell, in any one of the first to fifth embodiments, the outer circumferential surface of the cell body is covered with an insulating material in the portion that overlaps radially with respect to the easily breakable portion of the cell body.

[0018] In the sixth embodiment, on the outer surface of the cell body, the portion of the insulating film that overlaps radially with the easily breakable portion of the cell body is covered with an insulating material, thereby suppressing the reduction in insulating properties caused by the easily breakable portion of the insulating film.

[0019] In the seventh embodiment of the energy storage cell, in the sixth embodiment, the dimensions of the insulating material in the axial direction of the cell body are set to be larger than the dimensions of the easily breakable portion in the axial direction.

[0020] In the seventh embodiment, since the dimensions of the insulating material and the easily breakable portion are set as described above, even if the easily breakable portion breaks at an unintended time, it is possible to prevent the cell body from being exposed through the easily breakable portion and ensure insulation.

[0021] The energy storage cell of the eighth embodiment comprises a cylindrical cell body, an insulating film that covers the outer circumferential surface of the cell body and has an end-face covering portion that covers the axial end face of the cell body, and a conductive portion that is conductive, provided on the surface of the insulating film, and has a circumferentially extending portion that extends in the circumferential direction of the outer circumferential surface of the insulating film, and a pair of contact portions that extend from both ends of the circumferentially extending portion to the end-face covering portion.

[0022] In the eighth aspect, the insulating film covering the outer peripheral surface of the columnar cell body has an end face covering portion covering the end face in the axial direction of the cell body. A conductive portion having conductivity is provided on the surface of the insulating film. The conductive portion has a circumferential direction extending portion extending in the circumferential direction of the outer peripheral surface of the insulating film, and a pair of contact portions extending from both ends of the circumferential direction extending portion and reaching the end face covering portion. By bringing the positive electrode and the negative electrode of the power supply into contact with these contact portions and energizing the conductive portion, the insulating film can be broken by the heat generated by the conductive portion. Thereby, the insulating film can be easily removed from the cell body.

[0023] The power storage cell according to the ninth aspect includes a columnar cell body, an insulating film covering the outer peripheral surface of the cell body and having an end face covering portion covering the end face in the axial direction of the cell body, and an insulating ring provided between the end face of the cell body and the end face covering portion and having a protrusion on a surface facing the end face covering portion.

[0024] In the ninth aspect, the insulating film covering the outer peripheral surface of the columnar cell body has an end face covering portion covering the end face in the axial direction of the cell body. An insulating ring is provided between the end face covering portion and the end face in the axial direction of the cell body. The insulating ring has a protrusion on a surface facing the end face covering portion. Therefore, for example, by pushing the cell body axially against the insulating film from the other end side in the axial direction, the end face covering portion can be broken by the above-mentioned protrusion. Thereby, the insulating film can be easily removed from the cell body.

[0025] The power storage cell according to the tenth aspect is the same as the ninth aspect, wherein the protrusions are provided on both sides in the radial direction passing through the center of the insulating ring.

[0026] In the tenth aspect, by pushing the cell body axially against the insulating film from the other end side in the axial direction, the end face covering portion can be broken by the protrusions provided on both sides in the radial direction of the insulating ring as described above. Thereby, the insulating film can be removed from the cell body more easily.

[0027] In the power storage cell of the eleventh aspect, in the ninth aspect or the tenth aspect, the protrusion has an acute-angled corner portion, and the corner portion contacts the end face covering portion.

[0028] In the eleventh aspect, since the acute-angled corner portion of the protrusion of the insulating ring contacts the end face covering portion of the insulating film, the end face covering portion can be easily broken.

[0029] The power storage device of the twelfth aspect includes a holder in which a cell insertion hole is formed, and a power storage cell of any one of the first aspect to the seventh aspect, in which the outer peripheral surface of the insulating film is fixed to the inner peripheral surface of the cell insertion hole at a position displaced in the axial direction of the cell body with respect to the easily breakable portion, and is inserted into the cell insertion hole.

[0030] In the twelfth aspect, a power storage cell is inserted into the cell insertion hole formed in the holder. The insulating film of the power storage cell is fixed to the inner peripheral surface of the cell insertion hole at a position displaced in the axial direction of the cell body with respect to the easily breakable portion. When removing the cell body from the above-described holder, by pushing the cell body from the side opposite to the side where the easily breakable portion is displaced as described above in the axial direction of the cell body, the insulating film is broken at the easily breakable portion. Thereby, the insulating film is divided into a portion fixed to the inner peripheral surface of the cell insertion hole and a portion not fixed. Thereby, the cell body can be removed from the holder together with the unfixed portion. Thereafter, the unfixed portion can be easily removed from the cell body.

[0031] The power storage device of the thirteenth aspect includes a holder in which a cell insertion hole is formed, and a power storage cell of the eighth aspect, in which the outer peripheral surface of the insulating film is fixed to the inner peripheral surface of the cell insertion hole at a portion overlapping the pair of contact portions, and is inserted into the cell insertion hole. [[ID=二十一]]

[0032] [[ID=二十二]] In the 13th embodiment, a storage cell is inserted into a cell insertion hole formed in a holder. The insulating film of the storage cell has its outer surface fixed to the inner surface of the cell insertion hole at the portion that overlaps with a pair of contact points of the conductive part. When removing the cell body from the holder, the positive and negative electrodes of the power supply are brought into contact with the pair of contact points, and current is passed through the conductive part, causing the insulating film to break due to the heat generated by the conductive part. This separates the insulating film into a portion fixed to the inner surface of the cell insertion hole and an unfixed portion. As a result, the cell body can be removed from the holder together with the unfixed portion. After that, the unfixed portion can be easily removed from the cell body.

[0033] The 14th embodiment of the energy storage device comprises a holder having a cell insertion hole formed therein, and an energy storage cell of any one of the 9th to 11th embodiments, which is inserted into the cell insertion hole and whose outer peripheral surface of the insulating film is fixed to the inner peripheral surface of the cell insertion hole.

[0034] In the 14th embodiment, a storage cell is inserted into a cell insertion hole formed in a holder. The insulating film of the storage cell has its outer surface fixed to the inner surface of the cell insertion hole. When removing the cell body from the holder, the cell body is pushed axially from the other end in the axial direction relative to the holder and insulating film, causing the projection of the insulating ring to break the covering portion of one end of the insulating film. This allows the cell body to be removed from the holder and insulating film.

[0035] In the energy storage device of the 15th embodiment, in any one of the 12th to 14th embodiments, the outer surface of the insulating film is adhered to the inner surface of the cell insertion hole.

[0036] In the 15th embodiment, the portion of the insulating film whose outer surface is adhered to the inner surface of the cell insertion hole is difficult to remove from the holder, but the cell body can be easily removed from the holder by the configuration of any one of the 12th to 14th embodiments. [Effects of the Invention]

[0037] As described above, according to the present invention, the insulating film can be easily removed from the cell body. [Brief explanation of the drawing]

[0038] [Figure 1] This is a perspective view showing a power storage device according to the first embodiment. [Figure 2] This is a front view showing a part of the energy storage device according to the first embodiment. [Figure 3] This is a front view showing the holder of the energy storage device according to the first embodiment. [Figure 4] This is a perspective view showing the battery cell of the energy storage device according to the first embodiment. [Figure 5] This is a first cross-sectional view showing a part of the energy storage device according to the first embodiment. [Figure 6] This is a second cross-sectional view showing a part of the energy storage device according to the first embodiment. [Figure 7] This is a cross-sectional view corresponding to Figure 6, which shows the cell body in the process of being removed. [Figure 8] This is a cross-sectional view showing a part of the energy storage device related to the comparative example. [Figure 9] This is a cross-sectional view showing a part of a storage cell according to a first modification of the first embodiment. [Figure 10] This is a cross-sectional view showing a part of a storage cell according to a second modified example of the first embodiment. [Figure 11] This is a perspective view showing a portion of the energy storage cell and the extrusion rod used during cell disassembly according to the second embodiment. [Figure 12] This is an end view showing an extruded rod. [Figure 13] This is a cross-sectional view showing a part of the energy storage cell according to the third embodiment. [Figure 14] This is a front view showing the insulating link of a power storage cell according to the third embodiment. [Figure 15] The configuration shown in Figure 13 is a view taken from the direction of arrow F15 in Figure 13. [Modes for carrying out the invention]

[0039] <First Embodiment> Hereinafter, an energy storage device 10 according to the first embodiment of the present invention will be described with reference to Figures 1 to 10. As shown in Figures 1 and 2, the energy storage device 10 according to this embodiment comprises a holder 12 and a plurality of energy storage cells (cylindrical batteries) 20.

[0040] As shown in Figures 1 to 3, the holder 12 is manufactured, for example, by resin injection molding, and has a plurality of cylindrical cell insertion sections 14 integrally. The plurality of cell insertion sections 14 are arranged radially to each other. The inside of each cell insertion section 14 is a cell insertion hole 16, and an energy storage cell 20 is inserted into each cell insertion hole 16.

[0041] The axial ends of each cell insertion hole 16 are closed by a plate-shaped member 18 attached to the holder 12. Multiple energy storage cells 20 are electrically connected via multiple busbars (not shown) attached to this plate-shaped member 18. This constitutes a battery pack.

[0042] As shown in Figures 2, 4 to 6, the energy storage cell 20 is composed of a cylindrical cell body 22 and an insulating film (cell film) 24 covering the outer surface of the cell body 22. The cell body 22 is, for example, a lithium-ion battery. A positive electrode 22A is provided at one end of the cell body 22 in the axial direction, and a negative electrode 22B is provided at the other end of the cell body 22 in the axial direction.

[0043] The insulating film 24 is a heat-shrinkable resin film (for example, made of polyvinyl chloride) that adheres tightly to the outer surface of the cell body 22 by heat shrinkage. As shown in Figures 5 and 6, the insulating film 24 integrally comprises a cylindrical outer covering portion 24A that covers the outer surface of the cell body 22, an end covering portion 24B that extends radially inward from one axial end of the outer covering portion 24A and covers one axial end surface of the cell body 22, and an end covering portion 24C that extends radially inward from the other axial end of the outer covering portion 24A and covers the other axial end surface of the cell body 22.

[0044] Note that the insulating film 24 does not need to be heat-shrinkable. Also, in Figure 5, only the cell insertion portion 14 of the holder 12 and the energy storage cell 20 is shown in cross-section, and in Figures 6 and 7, only the cell insertion portion 14 and the insulating film 24 of the cell insertion portion 14, insulating film 24 and cell body 22 are shown in cross-section.

[0045] A portion of the outer surface of the insulating film 24 (i.e., the outer surface of the outer covering portion 24A) is bonded (fixed) to a portion of the inner surface of the cell insertion hole 16 by adhesive 26. The adhesive 26 is located in the gap between the outer surface of the outer covering portion 24A and the cell insertion hole 16, on the other end side (the other end covering portion 24C side) of the energy storage cell 20 rather than the axial center of the energy storage cell 20. This adhesive 26 extends in an annular shape continuously in the circumferential direction of the insulating film 24. Alternatively, for example, instead of adhesive 26, an annular fixing device made of rubber or the like may be used to fix the outer surface of the insulating film 24 to the inner surface of the cell insertion hole 16.

[0046] A cut line 28 is formed on the outer peripheral covering portion 24A of the insulating film 24 at a location offset to one side in the axial direction of the cell body 22 relative to the adhesive 26. The portion of the outer peripheral covering portion 24A where the cut line 28 is formed is designated as an easily breakable portion. The cut line 28 consists of numerous slits (reference numerals omitted) that penetrate the outer peripheral covering portion 24A in the radial direction of the cell body 22 and extend in the circumferential direction of the cell body 22, arranged at equal intervals in the circumferential direction of the cell body 22. In the locations where numerous slits (corresponding to the "thin-walled portion" in this invention) are formed, the thickness of the insulating film is locally thinned (in this case, to zero).

[0047] The easily breakable portion (hereinafter referred to as "easily breakable portion 28") on which the above-mentioned cut line 28 is formed is configured such that when an external force is applied, the portion between the numerous slits easily breaks. This easily breakable portion 28 is provided in an annular shape so as to encircle the outer peripheral covering portion 24A in the circumferential direction.

[0048] The outer surface of the cell body 22 is covered with a potting resin 30, which is an insulating material, in the portion that overlaps radially with the easily breakable portion (cut line) 28. The potting resin 30 is an insulating resin such as urethane resin, epoxy resin, or silicone resin, and is placed between the outer surface covering portion 24A and the cell body 22. This potting resin 30 extends continuously in an annular shape in the circumferential direction of the cell body 22. The width dimension of the potting resin 30 in the axial direction of the cell body is set to be larger than the width dimension of the easily breakable portion in the axial direction.

[0049] Next, the operation and effects of this embodiment will be described.

[0050] In the energy storage cell 20 with the above configuration, the outer surface of the cylindrical cell body 22 is covered with an insulating film 24. The insulating film 24 has an easily breakable portion 28. When disassembling the energy storage cell 20 for recycling or other purposes, the insulating film 24 can be easily removed from the cell body 22 by breaking the insulating film 24 at the easily breakable portion 28.

[0051] Furthermore, since the easily breakable portion 28 extends in the circumferential direction of the cell body 22, the insulating film 24 can be easily removed from the cell body 22 while suppressing a decrease in the insulating properties of the insulating film 24. Moreover, since the easily breakable portion 28 has numerous slits (thin-walled portions; no reference numerals are omitted) in which the thickness of the insulating film 24 is locally reduced (in this case, to zero), the easily breakable portion 28 can be easily broken starting from the numerous slits.

[0052] Furthermore, the outer surface of the cell body 22 is covered with potting resin 30 in the portion that overlaps with the easily breakable portion 28 in the radial direction of the cell body 22. This suppresses the reduction in insulation performance caused by the provision of an easily breakable portion (cut line) 28 in the insulating film 24. Moreover, the width dimension of the potting resin 30 in the axial direction of the cell body 22 is set to be larger than the width dimension of the easily breakable portion 28 in the axial direction of the cell body 22. Therefore, even if the easily breakable portion 28 breaks at an unintended time, it is possible to suppress the exposure of the cell body 22 through the easily breakable portion 28 and ensure insulation performance.

[0053] Furthermore, in the energy storage device 10 according to this embodiment, the energy storage cell 20 is inserted into the cell insertion hole 16 formed in the holder 12. The insulating film 24 of the energy storage cell 20 is fixed to the inner surface of the cell insertion hole 16 at a location offset from the easily breakable portion 28 towards the other end in the axial direction of the cell body 22.

[0054] When removing the cell body 22 from the holder 12, the insulating film 24 is ruptured at the easily breakable portion 28 by pushing the cell body 22 from the other end in the axial direction (see arrow P in Figure 7). This divides the insulating film 24 into a portion 241 fixed to the inner circumferential surface of the cell insertion hole and an unfixed portion 242. As a result, the cell body 22 can be removed from the holder 12 together with the unfixed portion 242. After that, the unfixed portion 242 can be easily removed from the cell body 22.

[0055] Furthermore, in this embodiment, the outer surface of the insulating film 24 is adhered to the inner surface of the cell insertion hole 16. Therefore, the portion 242 of the insulating film 24 whose outer surface is adhered to the inner surface of the cell insertion hole 16 is difficult to remove from the holder 12, but the above configuration makes it easy to remove the cell body 22 from the holder 12. As a result, disassembly of the energy storage device 10 becomes easier.

[0056] In other words, as shown in the comparative example in Figure 8, in a configuration where the insulating film 24 does not have an easily breakable portion 28, even if the cell body 22 is pushed from the other end in the axial direction, it is difficult to remove the cell body 22 from the holder 12 because the insulating film 24 is firmly bonded to the holder 12 by the adhesive 26. Therefore, disassembly of the energy storage device becomes difficult, but this can be resolved in this embodiment.

[0057] Furthermore, as shown in the first modified example in Figure 9, if a recess 32 extending in the circumferential direction is formed on the outer surface of the cell body 22, it is preferable to provide an easily breakable portion (in this case, a cut line) 28 in the insulating film 24 in a portion that is not in contact with the recess. This suppresses the reduction in insulating properties caused by the provision of the easily breakable portion 28 in the insulating film 24. The recess 32 is, for example, a crimped portion formed in the housing of the cell body 22.

[0058] Furthermore, as shown in the second modified example in Figure 10, a thin-walled portion 34, where the thickness of the insulating film 24 is locally reduced, may be extended in the circumferential direction of the cell body 22 to serve as an easily breakable portion. The insulating film 24 can be easily broken starting from this thin-walled portion 34. In addition, since this thin-walled portion 34 extends continuously in an annular shape in the circumferential direction of the cell body 22, the insulating film 24 can be removed from the cell body 22 more easily (with less force).

[0059] Next, other embodiments of the present invention will be described. Note that components and operations that are essentially the same as those in the first embodiment will be given the same reference numerals as in the first embodiment, and their descriptions will be omitted.

[0060] <Second Embodiment> Figure 11 shows a perspective view of a storage cell 20 according to a second embodiment of the present invention and a part of an extrusion rod 42 used when disassembling the cell. In this storage cell 20, the insulating film 24 does not have an easily breakable portion 28. Instead, in this storage cell 20, a conductive portion 40 is provided on the surface of the insulating film 24. In a power storage device (not shown) composed of multiple storage cells 20, similar to the power storage device 10 according to the first embodiment, multiple storage cells 20 are inserted into multiple cell insertion holes 16 of a holder 12 (see Figures 1 to 3), and the outer surface of the insulating film 24 is bonded to the inner surface of the cell insertion hole 16 by adhesive 26.

[0061] The conductive portion 40 is made of, for example, a conductive plating and is provided on the surface of the outer peripheral coating portion 24A on the other axial end side (negative electrode 22B side) of the cell body 22. This conductive portion 40 has a circumferentially extending portion 40A that extends in the circumferential direction on the outer peripheral surface of the outer peripheral coating portion 24A, and a pair of contact portions 40B that extend from both ends of the circumferentially extending portion 40A to the other end coating portion 24C. In this embodiment, the other end coating portion 24C corresponds to the "end face coating portion" in the present invention.

[0062] The circumferentially extending portion 40A is annular (approximately C-shaped) in the circumferential direction of the outer surface of the outer peripheral covering portion 24A. The pair of contact portions 40B extend from both ends of the circumferentially extending portion 40A toward the other end of the cell body 22 in the axial direction, then extend toward opposite sides of the cell body 22 in the circumferential direction, and then bend toward the other end of the cell body 22 in the axial direction at positions opposite each other across the axis of the cell body 22, extending to the other end covering portion 24C. The outer peripheral surface of the insulating film 24 is adhered (fixed) to the inner peripheral surface of the cell insertion hole 16 in the portion that overlaps with the pair of contact portions 40B.

[0063] In this embodiment, when removing the insulating film 24 from the cell body 22, the positive and negative electrodes of the power supply are brought into contact with the pair of contact portions 40B, and current is passed through the conductive portion 40. This causes the insulating film 24 to break due to the heat generated by the conductive portion 40. As a result, the insulating film 24 can be easily removed from the cell body 22.

[0064] Furthermore, in this embodiment, when removing the cell body 22 from the holder 12, the end face of the extrusion rod 42 is pressed against the other axial end face of the cell body 22, bringing the positive electrode 42A and negative electrode 42B provided on the end face of the extrusion rod 42 into contact with the pair of contact portions 40B. The positive electrode 42A and negative electrode 42B are electrically connected to a power supply, and when current is passed through the conductive portion 40, the insulating film 24 is broken by the heat generated by the conductive portion 40. The insulating film 24 is then divided into a portion 241 fixed to the inner circumferential surface of the cell insertion hole 16 and an unfixed portion 242. As a result, the cell body 22 can be removed from the holder 12 together with the unfixed portion 242. After that, the unfixed portion 242 can be easily removed from the cell body 22.

[0065] <Third Embodiment> Figure 13 shows a cross-sectional view of a part of a storage cell 20 according to the third embodiment of the present invention. In this storage cell 20, the insulating film 24 does not have an easily breakable portion 28. Instead, in this storage cell 20, an insulating ring 46 provided between one axial end face of the cell body 22 and one end covering portion 24B of the insulating film 24 has two protrusions 46B. In a power storage device (not shown) composed of multiple storage cells 20, similar to the power storage device 10 according to the first embodiment, multiple storage cells 20 are inserted into multiple cell insertion holes 16 of a holder 12 (see Figures 1 to 3), and the outer circumferential surface of the insulating film 24 is bonded to the inner circumferential surface of the cell insertion hole 16 by adhesive 26.

[0066] As shown in Figures 13 and 14, the insulating ring 46 is formed in a disc shape and consists of a ring body 46A arranged coaxially with the cell body 22, and two protrusions 46B provided on the surface of the ring body 46A facing the one-end covering portion 24B. This insulating ring 46 is manufactured, for example, by resin injection molding. In this embodiment, the one-end covering portion 24B corresponds to the "end face covering portion" in the present invention.

[0067] A circular through-hole 48 is formed in the center of the ring body 46A through which the positive electrode 22A of the cell body 22 is inserted. The two protrusions 46B are located at both ends of the ring body 46A in the radial direction (opposite each other via the through-hole 48) from the center. The two protrusions 46B are roughly triangular plate-shaped, and the height of the protrusion from the ring body 46A increases as it moves radially outward from the ring body 46A. At each protrusion 46B, an acute-angled corner SC is provided at the radially outer end of the ring body 46A, and each corner SC is in contact with the covering portion 24B at one end.

[0068] In this embodiment, the one-end covering portion 24B can be broken by the projection 46B when the cell body 22 is pushed axially against the insulating film 24 from the other end in the axial direction (see dashed line DL in Figure 15). This allows the insulating film 24 to be easily removed from the cell body 22. Furthermore, in this embodiment, since projections 46B are provided on both radial sides of the center of the ring body 46A, the one-end covering portion 24B can be broken on both radial sides of the cell body 22. This makes it even easier to remove the insulating film 24 from the cell body 22. Moreover, in this embodiment, the sharp corners SC of each projection 46B come into contact with the one-end covering portion 24B, allowing the one-end covering portion to be easily broken.

[0069] Furthermore, in this embodiment, when removing the cell body 22 from the holder 12, the cell body 22 is pushed axially from the other end in the axial direction relative to the holder 12 and the insulating film 24, causing the projection 46B of the insulating ring 46 to break the one-end covering portion 24B of the insulating film 24. This allows the cell body 22 to be removed from the holder 12 and the insulating film 24.

[0070] Although the present invention has been described above with reference to several embodiments, the present invention can be implemented with various modifications without departing from its spirit. Furthermore, it goes without saying that the scope of the present invention is not limited to the above-described embodiments. [Explanation of symbols]

[0071] 10 Energy storage device 12 holders 16 cell insertion holes 20 energy storage cells 22 Cell Body 24 Insulating film 24B One end covering part (end face covering part) 24C Other end covering part (end face covering part) 28. Cutting line (easily breakable section) 30. Potting resin (insulating material) 32 dents 34. Thin-walled section (easily fractured section) 40 Conductive part 40A Circumferential extension part 40B Contact part 46 Insulating rings 46A Ring body 46B Protrusion SC corner

Claims

1. A cylindrical cell body, An insulating film covering the outer surface of the cell body and having an easily breakable portion, A battery storage cell equipped with the following features.

2. The energy storage cell according to claim 1, wherein the easily breakable portion extends in the circumferential direction of the cell body.

3. The energy storage cell according to claim 2, wherein the easily breakable portion has a thin-walled portion in which the thickness of the insulating film is locally reduced.

4. The energy storage cell according to claim 3, wherein the thin-walled portion extends in an annular shape continuously in the circumferential direction of the cell body.

5. The cell body has a recess on its outer surface, The energy storage cell according to claim 1 or claim 2, wherein the easily breakable portion is provided in the insulating film on the portion facing the recess.

6. The energy storage cell according to claim 1 or claim 2, wherein the outer surface of the cell body is covered with an insulating material in the portion that overlaps with the easily breakable portion in the radial direction of the cell body.

7. The energy storage cell according to claim 6, wherein the dimensions of the insulating material in the axial direction of the cell body are set to be larger than the dimensions of the easily breakable portion in the axial direction.

8. A cylindrical cell body, An insulating film having an end-face covering portion that covers the outer circumferential surface of the cell body and the axial end face of the cell body, A conductive portion having conductivity, provided on the surface of the insulating film, and having a circumferentially extending portion that extends in the circumferential direction of the outer surface of the insulating film, and a pair of contact portions that extend from both ends of the circumferentially extending portion to the end face covering portion, A battery storage cell equipped with the following features.

9. A cylindrical cell body, An insulating film having an end-face covering portion that covers the outer circumferential surface of the cell body and the axial end face of the cell body, An insulating ring is provided between the end face of the cell body and the end face covering portion, and has a projection on the surface facing the end face covering portion, A battery storage cell equipped with the following features.

10. The energy storage cell according to claim 9, wherein the protrusions are provided on both sides in the radial direction through the center of the insulating ring.

11. The energy storage cell according to claim 9 or claim 10, wherein the projection has an acute corner, and the corner contacts the end face covering.

12. A holder with a cell insertion hole formed therein, A power storage cell according to claim 1, wherein the cell insertion hole is inserted and the outer surface of the insulating film is fixed to the inner surface of the cell insertion hole at a location offset in the axial direction of the cell body relative to the easily breakable portion, A power storage device equipped with the following features.

13. A holder with a cell insertion hole formed therein, A power storage cell according to claim 8, wherein the outer surface of the insulating film is inserted into the cell insertion hole and fixed to the inner surface of the cell insertion hole in the portion that overlaps with the pair of contact portions, A power storage device equipped with the following features.

14. A holder with a cell insertion hole formed therein, A storage cell according to claim 9, wherein the storage cell is inserted into the cell insertion hole and the outer peripheral surface of the insulating film is fixed to the inner peripheral surface of the cell insertion hole, A power storage device equipped with the following features.

15. The energy storage device according to any one of claims 12 to 14, wherein the outer surface of the insulating film is adhered to the inner surface of the cell insertion hole.

Images