CN221632701U

CN221632701U - Laminated battery and battery device

Info

Publication number: CN221632701U
Application number: CN202322835007.2U
Authority: CN
Inventors: 王珂; 许博伟; 赵幸一
Original assignee: China Innovation Aviation Technology Group Co ltd
Current assignee: China Innovation Aviation Technology Group Co ltd
Priority date: 2023-10-20
Filing date: 2023-10-20
Publication date: 2024-08-30
Anticipated expiration: 2033-10-20

Abstract

The present utility model relates to a laminated battery and a battery device. Wherein the lamination battery includes: a battery case having a reverse arc angle therein; a pole piece having a right angle portion; wherein, the radius r of the reverse arc angle which is arranged in the battery shell opposite to the right angle part ranges from 0.5mm to 2.5mm. According to the laminated battery, the radius value of the reverse arc angle of the battery shell is set to be within 0.5-2.5 mm, so that the right angle part of the pole piece and the reverse arc angle of the battery shell cannot interfere due to the overlarge radius value of the reverse arc angle, and the normal performance of the battery is guaranteed. Meanwhile, the battery shell is not easy to form due to the fact that the radius value of the reverse arc angle is too small, so that the forming efficiency of the battery shell is improved, and the manufacturing difficulty is reduced.

Description

Laminated battery and battery device

Technical Field

The utility model relates to the technical field of batteries, in particular to a laminated battery and a battery device.

Background

The performance of the lithium ion power battery which is most widely applied in the industry is closely related to the process and manufacturing equipment, and the battery core can be divided into a winding process and a lamination process according to the manufacturing process. The lamination process is to cut the positive and negative plates into the required size, then stack the positive plates, the diaphragms and the negative plates into small cell units, and then stack and connect the small cell units in parallel to form the battery module. The lamination process has the advantages of high capacity density, high energy density and flexible size, and the battery cells of the lamination structure are increasingly becoming mainstream structures.

The existing laminated battery generally comprises a battery shell and pole pieces, wherein reverse arc angles are generally arranged at corners around the battery shell, and the radius of the reverse arc angles is R, so that the stress concentration of the battery shell can be reduced, and the compressive strength of the battery shell is ensured; and the four corners of the pole piece are usually subjected to right-angle die cutting in the positive and negative pole piece die cutting process to form right-angle parts, so that burrs at the corners of the positive and negative pole pieces are reduced, and the yield is improved.

However, when the pole piece and the battery case are assembled, the right angle part of the pole piece is easy to interfere with the reverse arc angle of the battery case to influence the battery performance, and there is an improvement.

Disclosure of utility model

In order to overcome at least one of the drawbacks of the prior art described above, according to an aspect of the present utility model, a laminated battery is provided to improve the molding efficiency of the battery case while preventing interference of the right angle portion of the pole piece with the reverse arc angle of the battery case.

A laminated battery comprising: a battery case having a reverse arc angle therein; a pole piece having a right angle portion; the reverse arc angle and the right angle part are arranged oppositely, and the radius r of the reverse arc angle is more than or equal to 0.5mm and less than or equal to 2.5mm.

In view of the problem that when the existing laminated battery is assembled, the right angle part of the pole piece is easy to interfere with the reverse arc angle of the battery shell to influence the battery performance, the radius value of the reverse arc angle of the battery shell is set to be within 0.5-2.5 mm (including the end point value), and the right angle part of the pole piece and the reverse arc angle of the battery shell cannot interfere due to the overlarge radius value of the reverse arc angle, so that the battery performance is ensured to be normally exerted. Meanwhile, the battery shell is not easy to form due to the fact that the radius value of the reverse arc angle is too small, so that the forming efficiency of the battery shell is improved, and the manufacturing difficulty is reduced.

According to a further aspect of the present application there is provided a battery device comprising a laminated battery as described above.

Drawings

Fig. 1 is a sectional view showing an internal structure of a laminated battery according to an embodiment of the present utility model;

FIG. 2 is an enlarged view of a portion of FIG. 1 at A;

fig. 3 is another cross-sectional view of the internal structure of a laminated battery according to an embodiment of the present utility model;

FIG. 4 is a schematic illustration of the assembly of pole pieces and pallets of a laminated battery according to an embodiment of the present utility model;

FIG. 5 is a schematic illustration of the assembly of pole pieces, separator and pallet of a laminated battery according to an embodiment of the utility model;

FIG. 6 is a cross-sectional view of a laminated battery pole piece and first protective film assembly according to an embodiment of the present utility model;

The accompanying drawings: 1-battery shell, 11-reverse arc angle, 12-first side wall, 13-second side wall, 14-bottom wall, 2-electric core, 21-pole piece, 211-right angle part, 22-large surface, 3-supporting plate, 4-diaphragm and 5-first protection film.

Detailed Description

For a better understanding and implementation, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the drawings in the embodiments of the present utility model.

In the description of the present utility model, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, only for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements to be referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model.

At present, in the aspect of limiting the endurance mileage and the energy supplementing efficiency of a pure electric vehicle, the most core component is a power battery technology. At present, the main current manufacturing process of the battery cell in the industry is divided into winding and lamination. Typically, winding is used for square and cylindrical batteries and lamination is used for square and pouch batteries.

The winding process is to wind and extrude the positive pole piece, the diaphragm and the negative pole piece which are treated in the earlier stage in sequence through a fixed winding needle. The specific process is that a pole group is formed by the diaphragm, the positive pole, the diaphragm and the negative pole in sequence (from inside to outside), and the pole group is directly rolled into a cylindrical shape or an elliptic cylindrical shape by a winding method and then is placed in a cylindrical metal shell.

The lamination process is to laminate the battery isolating film, the positive plate and the negative plate. For example, a soft package battery is formed by stacking, such as a zigzag lamination, firstly cutting the raw materials of positive and negative electrodes into rectangular pole pieces with the same size, then respectively stacking the rectangular pole pieces on a diaphragm, enabling the diaphragm to pass through the zigzag lamination, separating the two poles, and finally packaging with aluminum plastic.

The existing laminated battery generally comprises a battery shell and pole pieces, wherein reverse arc angles are generally arranged at corners around the battery shell, and the radius of the reverse arc angles is R, so that the stress concentration of the battery shell can be reduced, and the compressive strength of the battery shell is ensured; and the four corners of the pole piece are usually subjected to right-angle die cutting in the positive and negative pole piece die cutting process to form right-angle parts, so that burrs at the corners of the positive and negative pole pieces are reduced, and the yield is improved. However, when the pole piece and the battery case are assembled, the right angle part of the pole piece is easy to interfere with the reverse arc angle of the battery case to influence the battery performance, and there is an improvement. Therefore, it is necessary to provide a laminated battery to prevent interference of the right angle portion of the pole piece and the reverse arc angle of the battery case.

Referring to fig. 1-6, a laminated battery is disclosed in accordance with an embodiment of the present utility model.

The laminated battery comprises a battery shell 1 and a pole piece 21, wherein a reverse arc angle 11 is arranged in the battery shell 1; a pole piece 21 having a right angle portion 211; the radius r of the reverse arc angle 11 provided in the battery case 1 opposite to the right angle portion 211 is in the range of 0.5mm to 2.5mm.

In view of the fact that the right-angle portion 211 of the pole piece 21 and the reverse arc angle 11 of the battery case 1 are easy to interfere and affect the battery performance during assembly of the conventional laminated battery, the radius value of the reverse arc angle 11 of the battery case 1 is set within 0.5mm-2.5mm, and the right-angle portion 211 of the pole piece 21 and the reverse arc angle 11 of the battery case 1 are not interfered due to the overlarge radius value of the reverse arc angle 11, so that the battery performance is ensured to be normally exerted. Meanwhile, the battery shell 1 is not easy to form due to the fact that the radius value of the reverse arc angle 11 is too small, so that the forming efficiency of the battery shell 1 is improved, the manufacturing difficulty is reduced, and two purposes are achieved.

Wherein the radius r of the chamfer 11 of the housing may alternatively be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.5mm, 2mm or 2.5mm, although in other embodiments the radius r of the chamfer 11 of the housing may be other values within 0.5mm-2.5 mm.

Specifically, the battery case 1 includes a bottom wall 14, and two first side walls 12 and two second side walls 13 located between the two first side walls 12 are disposed on the bottom wall 14 in opposite directions; the opposite direction between the two first side walls 12 is set as a first direction, the opposite direction between the two second side walls 13 is set as a second direction, and the direction perpendicular to the bottom wall 14 is set as a third direction. In the illustrated embodiment, the first direction is the X direction, the second direction is the Y direction, and the third direction is the Z direction.

Wherein optionally there is a reverse arc angle 11 between the first side wall 12 and the bottom wall 14, and the pole piece 21 has a large face 22, the large face 22 extending in the first direction.

Referring to fig. 1, alternatively, in the first direction, the thickness a of the first sidewall 12 may range from 0.15mm to 1mm.

In order to make the battery case 1 better molded and manufactured and have enough strength, the thickness a of the first side wall 12 of the battery case 1 is set within the range of 0.15mm-1mm, so that the thickness of the first side wall 12 of the battery case 1 does not cause difficulty in molding at the reverse arc angle 11 due to excessive thickness and insufficient strength due to excessive thickness, thereby facilitating easier molding of the battery case 1 at the reverse arc angle 11 and reducing manufacturing difficulty; at the same time, it has a sufficient thickness to ensure strength.

Wherein alternatively the thickness a of the first sidewall 12 may be 0.15mm, 0.3mm, 0.45mm, 0.6mm, 0.75mm, 0.9mm or 1mm. Of course, in other embodiments, the thickness a of the first sidewall 12 may have other values within the range of 0.15mm-1 mm.

Referring to fig. 1 and 3, alternatively, the thickness a of the first sidewall 12 in the first direction is greater than the thickness b of the second sidewall 13 in the second direction. In this way, the larger the radius r for forming the reverse arc angle 11, the better the right angle portion 211 of the pole piece 21 can be accommodated.

Referring to fig. 4, optionally, the laminated battery further includes a battery cell 2 and a supporting plate 3, the battery cell 2 includes a pole piece 21, the supporting plate 3 is disposed between the battery cell 2 and the battery case 1, and the hardness of the supporting plate 3 is smaller than that of the battery case 1.

In this way, by providing the support plate 3 between the battery cell 2 and the battery case 1, the battery case 1 can be effectively prevented from directly contacting the battery cell 2, and the battery cell 2 can be protected.

Referring to fig. 4, alternatively, in the first direction, the proportional relationship between the length c of the pallet 3 and the length d of the pole piece 21 ranges from: c/d is more than or equal to 0.9 and less than or equal to 1.1.

In order to facilitate assembly and improve the supporting effect on the pole piece 21, the proportional relationship between the length c of the supporting plate 3 and the length d of the pole piece 21 is set within the range of 0.9-1.1, so that the proportional relationship between the length c and the length d of the pole piece 21 does not influence the normal assembly of the pole piece 21 and the supporting plate 3 due to overlarge, meanwhile, the pole piece 21 cannot be well supported due to overlarge size, and the assembly efficiency is improved and meanwhile, the supporting effect is good.

Referring to fig. 5, optionally, a membrane 4 is provided between the pole piece 21 and the carrier 3, and in the third direction, the membrane 4 has a thickness e in the range of 8 μm to 20 μm.

In this way, by arranging the diaphragm 4 between the pole piece 21 and the supporting plate 3, and setting the thickness e of the diaphragm 4 in the range of 8 μm to 20 μm, the diaphragm 4 will not affect the transmission of particles in the electrolyte due to excessive thickness, and meanwhile, the diaphragm 4 can also prevent the pole piece 21 from directly contacting with the supporting plate 3, so as to improve the protection effect on the right-angle part of the pole piece 21, therefore, in the range of 8 μm to 20 μm, the diaphragm 4 will not weaken the protection effect due to excessive thinness, the right-angle part 211 of the battery cell 2 is prevented from puncturing the first protection film 5, and good protection effect on the pole piece 21 is also achieved under the condition of ensuring that the transmission of particles in the electrolyte is not affected.

Wherein optionally the membrane 4 has a thickness e of 8 μm, 10 μm, 12 μm, 14 μm, 16 μm, 18 μm or 20 μm. Of course, in other embodiments, the thickness e of the diaphragm 4 may also be other values in the range of 8 μm-20 μm.

Referring to fig. 6, the first protection film 5 is optionally wrapped around the cell 2, and the thickness f of the first protection film 5 itself ranges from 60 μm to 200 μm.

In this way, by wrapping the first protection film 5 outside the battery cell 2, the battery cell 2 can be prevented from being in direct contact with the battery case 1, the battery cell 2 and the insulation function can be protected, and meanwhile, the thickness f of the first protection film 5 is set within the range of 60 μm-200 μm, the first protection film 5 does not affect the battery energy density in the laminated battery due to excessive thickness, and meanwhile, the protection and insulation function to the right angle part 211 of the battery cell 2 is not weakened due to excessive thickness.

Optionally, the first protection film 5 may be a My ar film or other protection films that can protect and insulate the battery cell 2.

Optionally, in the first direction or in the second direction, the first protective film 5 protrudes from the supporting plate 3, so as to further improve the protection effect on the battery cells 2.

The embodiment of the utility model also discloses a battery device which comprises the laminated battery, so that the radius value of the reverse arc angle 11 is set to be within 0.5-2.5 mm, and the right angle part 211 of the pole piece 21 and the reverse arc angle 11 of the battery shell 1 cannot interfere due to the overlarge radius value of the reverse arc angle 11, so that the normal performance of the battery is ensured. Meanwhile, the battery shell 1 is not easy to form due to the fact that the radius value of the reverse arc angle 11 is too small, so that the forming efficiency of the battery shell 1 is improved, and the manufacturing difficulty is reduced. Wherein optionally, the battery device is a battery module, a battery pack or a battery pack.

The technical means disclosed by the scheme of the utility model is not limited to the technical means disclosed by the embodiment, and also comprises the technical scheme formed by any combination of the technical features. It should be noted that modifications and adaptations to the utility model may occur to one skilled in the art without departing from the principles of the present utility model and are intended to be within the scope of the present utility model.

Claims

1. A laminated battery, comprising:

a battery case (1) having a reverse arc angle (11) in the case;

a pole piece (21) having a right angle portion (211);

The reverse arc angle (11) of the battery shell (1) is opposite to the right angle part (211), and the radius r range of the reverse arc angle (11) is more than or equal to 0.5mm and less than or equal to 2.5mm.

2. A laminated battery according to claim 1, wherein the battery housing (1) comprises a bottom wall (14), said bottom wall (14) being provided with two first side walls (12) and two second side walls (13) located between the two first side walls (12) in opposite directions; defining a direction of opposition between two of said first side walls (12) as a first direction;

In the first direction, the thickness a of the first side wall (12) is in the range of 0.15mm < a < 1mm.

3. A laminated battery according to claim 2, wherein the thickness a of the first side wall (12) in a first direction is greater than the thickness b of the second side wall (13) in a second direction.

4. The laminated battery of claim 1, further comprising:

-a cell (2) comprising the pole piece (21);

A support plate (3) arranged between the battery cell (2) and the battery case (1), wherein the hardness of the support plate (3) is smaller than that of the battery case (1);

The battery shell (1) comprises a bottom wall (14), wherein two first side walls (12) and two second side walls (13) positioned between the two first side walls (12) are oppositely arranged on the bottom wall (14); the opposite direction between the two first side walls (12) is defined as a first direction, the opposite direction between the two second side walls (13) is defined as a second direction, and the direction perpendicular to the bottom wall (14) is defined as a third direction.

5. A laminated battery as in claim 4, wherein,

In the first direction, the proportional relationship between the length c of the supporting plate (3) and the length d of the pole piece (21) ranges from: c/d is more than or equal to 0.9 and less than or equal to 1.1.

6. A laminated battery according to claim 4, characterized in that a membrane (4) is arranged between the pole piece (21) and the carrier (3), the membrane (4) having a thickness e in the third direction in the range of 8 μm.ltoreq.e.ltoreq.20 μm.

7. The laminated battery according to claim 4, wherein the first protective film (5) is wrapped outside the battery cell (2), and the thickness f of the first protective film (5) is in the range of 60 μm or less and 200 μm or less.

8. A laminated battery according to claim 7, characterized in that the first protective film (5) is arranged protruding from the carrier (3) in a first direction or in a second direction.

9. A battery device comprising a laminated battery according to any one of claims 1-8.

10. The battery device of claim 9, wherein the battery device is a battery module or a battery pack.