JP2023140765A - Laminated cell and battery pack - Google Patents

Abstract

To provide a laminated cell and battery pack that can appropriately lay out detection lines and can be miniaturized.SOLUTION: A laminated cell 10 includes an electrode body 11, tab leads 12 and 13 connected to the electrode body 11, and an exterior body 20 that houses the electrode body 11 such that the tab leads 12 and 13 are exposed, and is made of a laminate film. The exterior body 20 includes an electrode body housing portion 23 that houses the electrode body 11, and an ear portion 24 extending outside the electrode body housing portion 23. A temperature detection line 16 and at least one of voltage detection lines 14 and 15 are arranged in a folded portion 25 obtained by folding back the ear portion 24, and is arranged so as to overlap with the electrode body housing portion 23.SELECTED DRAWING: Figure 1

Description

The present invention relates to a laminated cell and a battery pack mounted on a vehicle.

In recent years, research and development has been conducted on secondary batteries that contribute to energy efficiency, in order to ensure that more people have access to affordable, reliable, sustainable, and advanced energy.

Laminated cells are known as secondary batteries. The laminated cell is provided with a voltage detection line for battery control and a temperature detection line for temperature management. However, there was a problem in how to lay out these detection lines. For example, in the laminated cell of Patent Document 1, it is described that the voltage detection line is arranged in the ear part (heat seal part) of the exterior material.

Japanese Patent Application Publication No. 2004-31270

Furthermore, in order to mount as many batteries as possible inside the battery case, it is preferable to downsize the laminated cell. In the laminated cell described in Patent Document 1, although the space for the voltage detection line can be saved, the laminated cell itself cannot be miniaturized, and there is room for improvement.

The present invention provides a laminated cell and a battery pack in which detection lines can be appropriately laid out and miniaturization is possible. This in turn contributes to energy efficiency.

[1] The present invention includes:
an electrode body;
a tab lead connected to the electrode body;
A laminate type cell, comprising: an exterior body that houses the electrode body so that the tab lead is exposed and is made of a laminate film,
The exterior body is
an electrode body housing part that houses the electrode body;
an ear portion located outside the electrode body accommodating portion,
At least one detection line of a temperature detection line connected to the exterior body and a voltage detection line connected to the tab lead is arranged in a folded part obtained by folding back the ear part and arranged so as to overlap with the electrode body housing part. be done.

[2] Furthermore, the battery pack of the present invention includes:
A cell group in which a plurality of laminated cells according to [1] are stacked horizontally,
A battery case that accommodates the cell group,
The folded portion is formed by folding back the ear portion located above or the ear portion located below in the height direction.

According to the present invention, detection lines can be appropriately laid out, and laminated cells and battery packs can be miniaturized. This in turn can contribute to energy efficiency.

FIG. 1 is an external perspective view of a laminate cell 10 according to a first embodiment. FIG. 2 is a schematic diagram of the AA cross section in FIG. 1. FIG. FIG. 2 is an explanatory assembly diagram showing a state before the ear portion 24 is folded back in the laminated cell 10 of FIG. 1. FIG. FIG. 3 is an external perspective view of a laminated cell 10 according to a second embodiment. 5 is a schematic diagram of a cross section taken along line BB in FIG. 4. FIG. FIG. 7 is a schematic cross-sectional view of a laminated cell 10 according to a modification of the second embodiment. FIG. 7 is an explanatory assembly diagram showing a state before the ear portions 24 are folded back in the laminated cell 10 of the third embodiment. 8 is a schematic cross-sectional view of the laminated cell 10 of FIG. 7. FIG. FIG. 7 is an explanatory assembly diagram showing a state before the ear portion 24 is folded back in the laminated cell 10 according to the fourth embodiment of the present invention. It is an external perspective view which shows the assembly procedure of the laminated cell 10 of 5th Embodiment of this invention. FIG. 10 is a schematic diagram of the DD cross section in FIG. 10(c). FIG. 2 is a schematic cross-sectional view of a battery pack 40 in which a cell group 41 consisting of a plurality of laminated cells 10 of the present invention is incorporated.

EMBODIMENT OF THE INVENTION Hereinafter, each embodiment of the laminated type cell of this invention is described based on an accompanying drawing.

[First embodiment]
A laminated cell according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3.

First, all-solid-state batteries will be explained.
An all-solid-state battery has a positive electrode for an all-solid-state battery, a negative electrode for an all-solid-state battery, and a solid electrolyte placed between the positive electrode for an all-solid-state battery and the negative electrode for an all-solid-state battery. The all-solid-state battery is charged and discharged by transferring lithium ions between the all-solid-state battery positive electrode and the all-solid-state battery negative electrode.

The solid electrolyte is not particularly limited as long as it has lithium ion conductivity and insulation, and materials commonly used in all-solid-state lithium ion batteries can be used. For example, sulfide solid electrolyte materials, oxide solid electrolyte materials, inorganic solid electrolytes such as lithium-containing salts, polymer-based solid electrolytes such as polyethylene oxide, and gel-based solid electrolytes including lithium-containing salts and lithium-ion conductive ionic liquids. Examples include solid electrolytes. The form of the solid electrolyte material is not particularly limited, but may be in the form of particles, for example.

In the laminated cell 10 of this embodiment, as shown in FIGS. 1 and 2, the above-described positive electrode for an all-solid-state battery, negative electrode for an all-solid-state battery, and solid electrolyte constitute an electrode body 11, and the overall shape is a substantially rectangular parallelepiped. is formed. A positive electrode tab lead 12 and a negative electrode tab lead 13 for outputting voltage from the electrode body 11 are connected to both longitudinal ends of the positive electrode for an all-solid-state battery and the negative electrode for an all-solid-state battery, respectively.

The electrode body 11 is entirely covered with an exterior body 20 formed of a laminate film, except for the positive electrode tab lead 12 and the negative electrode tab lead 13. The exterior body 20 includes an upper exterior sheet 21 that covers the upper surface of the electrode assembly 11 and a lower exterior sheet 22 that covers the lower surface of the electrode assembly 11 . Note that the upper exterior sheet 21 and the lower exterior sheet 22 may be a single sheet with at least one end connected, or may be separate sheets. In FIG. 2, the upper exterior sheet 21 and the lower exterior sheet 22 are shown separated for ease of understanding, but in reality, the later-described ears 24 of the upper exterior sheet 21 and the lower exterior sheet 22 are formed by adhesive etc. are in close contact with each other. The same applies to FIGS. 5, 6, 8, 11, and 12.

The size of the upper exterior sheet 21 and the lower exterior sheet 22 is such that the length in the longitudinal direction is shorter than the length from the tip of the positive electrode tab lead 12 to the tip of the negative electrode tab lead 13. On the other hand, the length in the lateral direction (in the present embodiment, the front-back direction) is longer than the length in the lateral direction of the electrode body 11 . That is, when the upper and lower surfaces of the electrode body 11 are covered with the exterior body 20 (upper exterior sheet 21 and lower exterior sheet 22), the electrode body 11 is covered with the electrode body with the tips of the positive electrode tab lead 12 and the negative electrode tab lead 13 exposed. It is covered with a housing part 23, and ear parts 24 are extended on both sides of the electrode body housing part 23 in the transverse direction.

The exterior body 20 has a multilayer structure in which a heat-fusible resin layer such as polyolefin is laminated on a metal layer made of aluminum, stainless steel (SUS), etc., for example. In addition to the above, the exterior body 20 may have a layer made of polyamide such as nylon, polyester such as polyethylene terephthalate, an adhesive layer made of any laminating adhesive, etc.

One end 14a of a voltage detection line 14 is connected to the positive tab lead 12 of the laminated cell 10, and one end 15a of a voltage detection line 15 is connected to the negative tab lead 13. The voltage detection line 15 is arranged along the longitudinal direction from the negative electrode tab lead 13 so as to overlap with the electrode body housing part 23 . The other ends of the voltage detection lines 14 and 15 are connected to a battery control device (not shown). Thereby, the cell voltage of the laminated cell 10 (electrode body 11) can be detected by the voltage detection lines 14 and 15 connected to the positive tab lead 12 and the negative tab lead 13.

Furthermore, a temperature sensor such as a thermistor is disposed at one end 16a of the temperature detection line 16, and is fixed to the exterior body 20. The temperature detection line 16 is arranged parallel to and adjacent to the voltage detection line 15 so as to overlap with the electrode body accommodating part 23 from approximately the center of the electrode body accommodating part 23 . The other end of the temperature detection line 16 is connected to a battery control device (not shown). Thereby, the temperature of the laminated cell 10 can be detected.

Next, with reference to FIG. 3, a procedure for assembling the laminated cell 10 will be described. As shown in FIG. 3, when the electrode body 11 is covered with the exterior body 20, ears 24 are developed on both sides of the electrode body 11 in the lateral direction. Then, the voltage detection line 15 and the temperature detection line 16 are arranged on the ear part 24 of the upper exterior sheet 21 along the longitudinal direction of the electrode body 11.

Next, as shown in FIG. 2, the ear portion 24 of the exterior body 20 on the side where the voltage detection line 15 and the temperature detection line 16 are arranged (the left side in FIG. 2) is set near the root of the electrode body 11. It is folded back by 180 degrees along the line L1 to form a folded part 25, and is overlapped with the electrode body accommodating part 23 with the voltage detection line 15 and the temperature detection line 16 wrapped in the folded part 25. Then, one end 15a of the voltage detection line 15 is connected to the negative tab lead 13, and a temperature sensor provided at one end 16a of the temperature detection line 16 is fixed to the exterior body 20.

Thereby, the voltage detection line 15 and the temperature detection line 16 are arranged so as to overlap with the electrode body housing part 23 while being covered by the folded part 25 . Therefore, the layout of the voltage detection line 15 and the temperature detection line 16 is improved, the laminated cell 10 can be downsized, and the voltage detection line 15 and the temperature detection line 16 can be protected by the exterior body 20.

[Second embodiment]
Next, a laminated cell 10 according to a second embodiment of the present invention will be described with reference to FIGS. 4 and 5. In each of the following descriptions, the same components as those of the laminated cell 10 of the first embodiment are given the same reference numerals, and the description will be omitted or simplified.

As explained in the first embodiment, in the laminated cell 10 of this embodiment, the voltage detection line 15 and the temperature detection line 16, which are covered with the folded part 25 and arranged to overlap with the electrode body housing part 23, are It is accommodated together with the folded portion 25 in a cover member 30 having a substantially U-shaped cross section and disposed outside of the folded portion 25 .

According to the laminated cell 10 of this embodiment, since the voltage detection line 15 and the temperature detection line 16 are covered twice with the exterior body 20 (folded part 25) and the cover member 30, the voltage detection line 15 and the temperature detection line 16 are The detection line 16 can be protected more reliably.

Note that the cover member 30 may be a seal member (not shown) that covers the folded portion 25. Thereby, the folded portion 25 can be fixed to the exterior body 20 by the sealing member.

Next, a laminated cell 10 according to a modification of the second embodiment will be described with reference to FIG. 6. In the laminated cell 10 of this modification, the gap (open end) between the cover member 30, which has a substantially U-shaped cross section, and the exterior body 20 is closed by a closing member 31. The cover member 30 and the closing member 31 have an engaging portion 32 and an engaged portion 33 that face each other, and when the engaging portion 32 and the engaged portion 33 engage, the cover member 30 and the exterior body 20 is fixed.

The closing member 31 is, for example, a rail-shaped member formed longitudinally on the surface of the exterior body 20, and may be formed directly on the outer surface of the exterior body 20, or a separately formed rail may be bonded with an adhesive. It may also be bonded to the exterior body 20 with. Furthermore, an engaged portion 33 that engages with the closing member 31 is provided on the inner surface of the cover member 30 facing the rail. Note that the engaging portion 32 may be formed on the inner surface of the cover member 30, and the engaged portion 33 may be provided on the closing member 31. According to the laminated cell 10 of this modification, the cover member 30 can be easily assembled.

[Third embodiment]
Next, a laminated cell 10 according to a third embodiment of the present invention will be described with reference to FIGS. 7 and 8.

In the laminated cell 10 of the present embodiment, the voltage detection line 15 and the temperature detection line 16 are inserted into a plurality of holes 26 provided in one (front side in FIG. 7) ear part 24, and are inserted from the front side to the back side. Further, they are alternately arranged on both sides of the ear portion 24 so as to stitch the ear portion 24 from the back side to the front side.

Then, the electrode body 11 is folded back by 180° at a first folding line L1 set near the root portion to form a folded part 25, and the electrode is wrapped around the voltage detection line 15 and the temperature detection line 16 by the folded part 25. It overlaps with the body accommodating part 23. The folded portion 25 may be fixed with a seal member or a cover member 30 (not shown).

According to the laminated cell 10 of this embodiment, the voltage detection line 15 and the temperature detection line 16 can be folded back in a solid state on the ear part 24, so that the work of assembling the voltage detection line 15 and the temperature detection line 16 is simplified. It becomes even easier.

[Fourth embodiment]
Next, a laminate type cell 10 according to a fourth embodiment of the present invention will be described with reference to FIG. 9. In the laminated cell 10 of this embodiment, the voltage detection line 15 and the temperature detection line 16 are inserted into the plurality of holes 26 provided in the ear part 24, and are inserted from the front side to the back side and from the back side to the front side. , are arranged alternately on both sides of the ear part 24 so as to stitch around the ear part 24. The temperature detection line 16 extends from approximately the center in the longitudinal direction of the electrode body 11 in the widthwise direction away from the electrode body 11, and is fixed to a temperature detection ear 24a formed continuously with the ear 24. There is.

Then, the temperature detection ear portion 24a is folded back by 180° together with the ear portion 24 to form a folded portion 25, and the voltage detection line 15 and the temperature detection line 16 are wrapped in the folded portion 25, and then connected to the electrode body housing portion 23. Overlap.

According to the laminated cell 10 of this embodiment, even if the temperature sensor provided at one end 16a of the temperature detection line 16 is separated from the ear portion 24 and fixed to the exterior body 20, the temperature sensor is attached to the temperature detection ear portion 24a. The temperature of the electrode body 11 can be detected with high accuracy. Moreover, all the detection lines (voltage detection line 15 and temperature detection line 16) can be covered and protected with the ears 24 and the temperature detection ears 24a.

[Fifth embodiment]
Next, a laminated cell 10 according to a fifth embodiment of the present invention will be described with reference to FIGS. 10 and 11. In the laminated cell 10 of the present embodiment, the voltage detection line 15 and the temperature detection line 16 are inserted through a plurality of holes 26 provided in the ear part 24, and are inserted from the front side to the back side and from the back side to the front side. They are alternately arranged on both sides of the ear part 24 so as to stitch the ear part 24.

Then, the ear part 24 is folded back 180 degrees at a second folding line L2 set at a position a predetermined distance away from the electrode body 11 (see FIG. 10(a)), and further, the second folding line L2 It is folded back by 180° at a first folding line L1 set closer to the electrode body 11 (see FIG. 10(b)). That is, the ear part 24 is folded back twice, and the voltage detection line 15 and the temperature detection line 16 are wrapped in the double folded part 25.

According to the laminated cell 10 of the present embodiment, the voltage detection line 15 and the temperature detection line 16 are covered twice by the ears 24, so that the voltage detection line 15 and the temperature detection line 16 are more appropriately protected. can do.

[Sixth embodiment]
Next, a battery pack 40 including a plurality of each of the laminated cells 10 described above will be described with reference to FIG. 12.

As shown in FIG. 12, the battery pack 40 includes a cell group 41 in which a plurality of laminated cells 10 described in the first to fifth embodiments are stacked horizontally, and the cell group 41 is connected to a battery case 42. They are housed in alignment. In each of the laminated cells 10, an ear portion 24 projecting upward in the figure is folded back by 180° downward to form a folded portion 25, which covers the voltage detection line 15 and the temperature detection line 16. Note that the folded portion 25 may be formed by folding the downwardly protruding ear portion 24 upward by 180°. In this case, the voltage detection line 15 and the temperature detection line 16 are also arranged below the electrode body 11.

According to the battery pack 40 of this embodiment, the height of the laminated cell 10 can be suppressed, and the battery pack 40 can be downsized. Moreover, since the voltage detection line 15 and the temperature detection line 16 are covered and fixed with the exterior body 20, the space inside the battery case 42 can be used effectively. Further, damage to the voltage detection line 15 and the temperature detection line 16 in the event of a collision can be suppressed. Note that the temperature detection line 16 does not need to be provided in all the laminated cells 10, and may be provided in at least one of the cell groups 41.

Although various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to such examples. It is clear that those skilled in the art can come up with various changes or modifications within the scope of the claims, and these naturally fall within the technical scope of the present invention. Understood. Further, each of the constituent elements in the above embodiments may be arbitrarily combined without departing from the spirit of the invention.

Furthermore, this specification describes at least the following matters. Note that, although components corresponding to those in the above-described embodiment are shown in parentheses, the present invention is not limited thereto.

(1) An electrode body (electrode body 11),
Tab leads (positive electrode tab lead 12, negative electrode tab lead 13) connected to the electrode body,
A laminate type cell (laminate type cell 10) comprising an exterior body (exterior body 20) made of a laminate film and housing the electrode body so that the tab leads are exposed,
The exterior body is
an electrode body housing part (electrode body housing part 23) that houses the electrode body;
an ear part (ear part 24) located outside the electrode body housing part,
At least one detection line of the temperature detection line (temperature detection line 16) connected to the exterior body and the voltage detection line (voltage detection lines 14, 15) connected to the tab lead is a folded part obtained by folding back the ear part. A laminate type cell which is arranged in the folded part 25 and is arranged so as to overlap with the electrode body accommodating part.

According to (1), the detection line is arranged in the folded part obtained by folding back the ear part of the exterior body and is arranged so as to overlap with the electrode body housing part, so that the layout of the detection line is improved. This allows the laminated cell to be downsized and save space when housed in a battery pack. Further, the detection line can be protected by the folded portion.

(2) The laminated cell according to (1),
The folded portion is a laminated cell that is folded back with the detection line disposed at the ear portion.

According to (2), the work of assembling the detection wires can be facilitated.

(3) The laminated cell according to (2),
The folded portion is a laminated cell that is folded back so that the detection line is sewn to the ear portion.

According to (3), since the detection wire can be folded back in a solid state on the ear portion, the work of assembling the detection wire can be further facilitated.

(4) The laminate cell according to (2) or (3),
The folded portion is a laminated cell, wherein the folded portion is folded back at least twice with the detection line disposed on the ear portion or sewn onto the ear portion.

According to (4), the detection line can be more appropriately protected.

(5) The laminated cell according to any one of (1) to (4),
Both the temperature detection line and the voltage detection line are arranged in the folded part along the longitudinal direction of the rectangular laminated cell and are arranged so as to overlap with the electrode body housing part,
The temperature detection line has a tip portion (one end 16a) extending in the widthwise direction from the middle in the lengthwise direction,
The exterior body is a laminate type cell in which the ear portion is provided with a temperature detection ear portion (temperature detection ear portion 24a) that covers the tip portion.

According to (5), the temperature detection line can be protected.

(6) The laminate cell according to any one of (1) to (5),
A laminate type cell provided with a cover member (cover member 30) that accommodates the folded portion.

According to (6), the detection line can be more appropriately protected.

(7) The laminated cell according to (6),
The cover member and the exterior body are laminated cells having an engaging portion (an engaging portion 32 and an engaged portion 33).

According to (7), the cover member can be easily assembled.

(8) The laminate cell according to any one of (1) to (5),
A laminate type cell including a sealing member that covers the folded portion.

According to (8), the folded portion can be fixed to the exterior body.

(9) A cell group (cell group 41) in which a plurality of laminated cells (laminated cells 10) according to any one of (1) to (8) are stacked in the horizontal direction;
A battery case (battery case 42) that accommodates the cell group,
In the battery pack (battery pack 40), the folded portion is formed by folding back the ear portion located above or the ear portion located below in the height direction.

According to (9), the height of the laminated cell can be suppressed, and the battery pack can be made smaller. Moreover, since the detection wire is fixed to the exterior body of each laminated cell, the space inside the case can be effectively utilized.

10 Laminated cell 11 Electrode body 12 Positive electrode tab lead (tab lead)
13 Negative tab lead (tab lead)
14, 15 Voltage detection line 16 Temperature detection line 16a One end (tip)
20 Exterior body 23 Electrode housing portion 24 Ear portion 24a Temperature detection ear portion 25 Folded portion 30 Cover member 32 Engagement portion (engagement portion)
33 Engaged part (engaging part)
40 Battery pack 41 Cell group 42 Battery case

Claims (9)

an electrode body;
a tab lead connected to the electrode body;
A laminate type cell, comprising: an exterior body that houses the electrode body so that the tab lead is exposed and is made of a laminate film,
The exterior body is
an electrode body housing part that houses the electrode body;
an ear portion located outside the electrode body accommodating portion,
At least one detection line of a temperature detection line connected to the exterior body and a voltage detection line connected to the tab lead is arranged in a folded part obtained by folding back the ear part and arranged so as to overlap with the electrode body housing part. Laminated cell. The laminated cell according to claim 1,
The folded portion is a laminated cell that is folded back with the detection line disposed at the ear portion. The laminated cell according to claim 2,
The folded portion is a laminated cell that is folded back so that the detection line is sewn to the ear portion. The laminate type cell according to claim 2 or 3,
The folded portion is a laminated cell, wherein the folded portion is folded back at least twice with the detection line disposed on the ear portion or sewn onto the ear portion. The laminated cell according to any one of claims 1 to 4,
Both the temperature detection line and the voltage detection line are arranged in the folded part along the longitudinal direction of the rectangular laminated cell and are arranged so as to overlap with the electrode body housing part,
The temperature detection line has a tip extending from the middle in the longitudinal direction in the transverse direction,
A laminate type cell, wherein the outer body is provided with a temperature detection ear portion that covers the tip portion in the ear portion. The laminate type cell according to any one of claims 1 to 5,
A laminate type cell provided with a cover member that accommodates the folded portion. The laminated cell according to claim 6,
The cover member and the exterior body are laminated cells having an engaging portion. The laminate type cell according to any one of claims 1 to 5,
A laminate type cell including a sealing member that covers the folded portion. A cell group in which a plurality of laminated cells according to any one of claims 1 to 8 are stacked in a horizontal direction;
A battery case that accommodates the cell group,
In the battery pack, the folded portion is formed by folding back an ear portion located above or a ear portion located below in the height direction.

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