Battery cell and battery pack

Abstract

The utility model relates to the technical field of lithium ion batteries, in particular to a battery cell and a battery pack. The battery cell comprises a shell, a positive plate, an insulating layer and a roll core, a cavity is formed in the shell, an opening is formed in one side of the shell, and a sinking groove is formed in the edge of the opening of the shell in the height direction of the shell; the edge of the positive plate is bent towards one side of the shell to form a positioning part, and the positioning part is clamped with the sinking groove; the insulating layer wraps the positioning part so as to isolate the shell from the positive plate; the roll core is arranged in the cavity, a positive tab of the roll core is connected with the positive plate, and a negative tab of the roll core is connected with the shell. The problem that in the prior art, a steel shell of a steel shell buckle type battery cell is complex in structure and not easy to assemble is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium ion batteries, in particular to a battery core and a battery pack. Background Art

[0002] Button cell is a common type of rechargeable battery, also known as lithium-ion battery. It consists of a shell (usually steel shell) enclosing the positive and negative electrodes and electrolyte of the battery. The design of button cell makes it suitable for many applications, such as portable electronic devices, power tools, electric vehicles, etc. They have high energy density, long life and low self-discharge rate, so they are widely used in many applications.

[0003] The outer shell of the steel shell button-type battery is usually made of steel, which has high strength and durability and can protect the components inside the battery from external damage. However, the steel shell structure of the existing steel shell button-type battery is relatively complex, which makes the assembly process time-consuming and labor-intensive, and is not conducive to industrial production. Utility Model Content

[0004] The technical problem to be solved by the embodiments of the utility model is to provide a battery cell and a battery pack to solve the problem that the steel shell structure of the steel shell button-type battery cell in the prior art is relatively complex, resulting in difficulty in assembly.

[0005] In the first aspect, the utility model discloses a battery cell, comprising: a shell, a positive electrode plate, an insulating layer and a winding core, wherein a cavity is formed in the shell, an opening is provided on one side of the shell, and a sinking groove is provided on the edge of the opening along the height direction of the shell; the edge of the positive electrode plate is bent toward one side of the shell to form a positioning portion, and the positioning portion is clamped with the sinking groove; the insulating layer covers the positioning portion to isolate the shell and the positive electrode plate; the winding core is arranged in the cavity, the positive electrode ear of the winding core is connected to the positive electrode plate, and the negative electrode ear of the winding core is connected to the shell.

[0006] Optionally, the insulating layer includes a first connecting segment, a second connecting segment, a third connecting segment and a fourth connecting segment that are interconnected, the first connecting segment is attached to the positive electrode plate near the positioning portion, the second connecting segment is attached to a side of the positioning portion facing the cavity, the third connecting segment is attached to a side of the positioning portion that is parallel to the positive electrode plate, and the fourth connecting segment is attached to a side of the positioning portion that is away from the cavity.

[0007] Optionally, the length of the positioning portion is a, and the depth of the sinking groove is b, wherein b>a.

[0008] Optionally, the width of the positioning portion is c, the thickness of the insulating layer is d, and the width of the sinking groove is e, wherein e>c+2d.

[0009] Optionally, the battery core further includes an adhesive layer, and the adhesive layer is arranged between the insulating layer and the sinking groove.

[0010] Optionally, the positive electrode plate is made of aluminum or steel.

[0011] Optionally, the shell is made of steel.

[0012] Optionally, the thickness of the positive electrode plate is 0.1 mm to 0.2 mm.

[0013] Optionally, the cross-section of the battery core is circular or rectangular.

[0014] In a second aspect, the utility model further discloses a battery pack, comprising a plurality of battery cells according to any one of the above items, wherein the plurality of battery cells are connected in series and / or in parallel.

[0015] Compared with the prior art, the beneficial effects of the battery cell and battery pack provided by the embodiments of the utility model are as follows: the shell provides external protection for the battery cell and forms a cavity so that the winding core inside the shell and the positive plate can be safely placed. The cooperative connection between the sinking groove at the edge of the shell opening and the positioning part of the positive plate increases the stability of the structure, prevents the movement or loosening of the connection between the shell and the positive plate, and the connection method of the positioning part and the sinking groove is clamped, without the intervention of welding or other connectors, which can effectively simplify the structure of the battery cell, facilitate the assembly of the battery cell, and facilitate production. The insulating layer covers the positioning part, which plays the role of isolating the shell and the positive plate, can prevent the battery short circuit between the positive plate and the shell, and improve the safety and reliability of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The technical solution of the utility model will be further described in detail below with reference to the accompanying drawings and embodiments, in which:

[0017] Figure 1 It is a schematic diagram of a battery cell provided by an embodiment of the utility model;

[0018] Figure 2 yes Figure 1 A partial enlarged schematic diagram of position A in the middle.

[0019] The reference numerals in the figures are:

[0020] 1000, battery cell; 100, shell; 101, cavity; 102, opening; 1021, sinking groove; 200, positive electrode plate; 201, positioning portion; 300, insulating layer; 301, first connecting section; 302, second connecting section; 303, third connecting section; 304, fourth connecting section; 400, winding core; 401, positive electrode ear; 402, negative electrode ear. DETAILED DESCRIPTION

[0021] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Now, in conjunction with the accompanying drawings, a preferred embodiment of the present utility model is described in detail.

[0022] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Now, in conjunction with the accompanying drawings, a preferred embodiment of the present utility model is described in detail.

[0023] The present utility model embodiment provides a battery cell 1000, such as Figure 1-2 As shown, the battery cell 1000 includes: a shell 100, a positive electrode plate 200, an insulating layer 300 and a winding core 400, a cavity 101 is formed in the shell 100, an opening 102 is provided on one side of the shell 100, and a sinking groove 1021 is provided at the edge of the opening 102 of the shell 100 along the height direction of the shell 100; the edge of the positive electrode plate 200 is bent toward one side of the shell 100 to form a positioning portion 201, and the positioning portion 201 is engaged with the sinking groove 1021; the insulating layer 300 covers the positioning portion 201 to isolate the shell 100 and the positive electrode plate 200; the winding core 400 is arranged in the cavity 101, the positive electrode ear 401 of the winding core 400 is connected to the positive electrode plate 200, and the negative electrode ear 402 of the winding core 400 is connected to the shell 100.

[0024] The shell 100 provides external protection for the battery cell 1000 and forms a cavity 101, so that the winding core 400 inside the shell 100 and the positive plate 200 can be safely placed. The cooperation and connection between the sinking groove 1021 at the edge of the opening 102 of the shell 100 and the positioning part 201 of the positive plate 200 increases the stability of the structure, prevents the movement or loosening of the connection between the shell 100 and the positive plate 200, and the clamping connection between the positioning part 201 and the sinking groove 1021 does not require the intervention of welding or other connectors, which can effectively simplify the structure of the battery cell 1000, facilitate the assembly of the battery cell 1000, and facilitate production. The insulating layer 300 covers the positioning part 201, plays the role of isolating the shell 100 and the positive plate 200, can prevent the battery short circuit between the positive plate 200 and the shell 100, and improve the safety and reliability of the battery cell 1000.

[0025] Specifically, the edge of the positive plate 200 is bent toward one side of the housing 100 to form a positioning portion 201, which is engaged with the sinking groove 1021 of the housing 100, so that the positive plate 200 can be accurately positioned inside the housing 100. This positioning method ensures the correct alignment of the positive plate 200 with other components and improves the assembly accuracy of the battery cell 1000.

[0026] Specifically, the winding core 400 is disposed in the cavity 101, the positive electrode ear 401 of the winding core 400 is connected to the positive electrode plate 200, and the negative electrode ear 402 of the winding core 400 is connected to the shell 100. This connection method can ensure the reliability of the electrical connection between the positive electrode plate 200 and the shell 100, reduce resistance, and improve the performance and efficiency of the battery cell 1000.

[0027] refer to Figure 2 The insulating layer 300 includes a first connecting segment 301, a second connecting segment 302, a third connecting segment 303 and a fourth connecting segment 304 which are connected to each other. The first connecting segment 301 is attached to the positive electrode plate 200 near the positioning portion 201, the second connecting segment 302 is attached to a side of the positioning portion 201 facing the cavity 101, the third connecting segment 303 is attached to a side of the positioning portion 201 which is arranged parallel to the positive electrode plate 200, and the fourth connecting segment 304 is attached to a side of the positioning portion 201 which is away from the cavity 101.

[0028] The first connecting section 301, the second connecting section 302, the third connecting section 303 and the fourth connecting section 304 are sequentially connected and cover various areas of the positioning portion 201, so that the positioning portion 201 is completely protected by the insulating layer 300, and the positioning portion 201 and the sinking groove 1021 are completely insulated and isolated, thereby preventing the battery cell 1000 from short circuiting, enhancing the insulation performance of the battery cell 1000, and reducing the risk of failure or malfunction of the battery cell 1000.

[0029] Different connecting sections of the insulating layer 300 are attached to different sides of the positioning portion 201 , so that the insulating layer 300 can be tightly connected to the sinking groove 1021 , providing additional fixation and connection tightness, and preventing the movement or loosening of the connection between the sinking groove 1021 and the positioning portion 201 .

[0030] Further, refer to Figure 2 The width of the positioning portion 201 is c, the thickness of the second connecting section 302 is d1, the thickness of the fourth connecting section 304 is d2, and the width of the sinking groove 1021 is e, wherein e>c+d1+d2.

[0031] Since the width e of the sinking groove 1021 is greater than the width c of the positioning portion 201 plus the thickness d1 of the second connecting segment 302 and the thickness d2 of the fourth connecting segment 304, that is, e>c+d1+d2, it is ensured that the width of the sinking groove 1021 is sufficient to accommodate the positioning portion 201 and the space of the second connecting segment 302 and the fourth connecting segment 304. In this way, when the positioning portion 201 is engaged with the sinking groove 1021, it is relatively easy to insert the positioning portion 201 into the sinking groove 1021, and during the connection process, the second connecting segment 302 and the fourth connecting segment 304 of the insulating layer 300 will not be squeezed or scratched due to insufficient space, thereby ensuring the integrity and insulation performance of the second connecting segment 302 and the fourth connecting segment 304.

[0032] It should be noted that, in the implementation process, the thickness d1 of the second connecting segment 302 may be the same as the thickness d2 of the fourth connecting segment 304 , or the thickness d1 of the second connecting segment 302 may be different from the thickness d2 of the fourth connecting segment 304 .

[0033] refer to Figure 1 , the length of the positioning portion 201 is a, and the depth of the sinking groove 1021 is b, wherein b>a.

[0034] Since the depth b of the sinking groove 1021 is greater than the length a of the positioning portion 201, it is ensured that the depth of the sinking groove 1021 is sufficient to accommodate the positioning portion 201. When the positioning portion 201 is engaged with the sinking groove 1021, the entire positioning portion 201 can be completely accommodated by the sinking groove 1021, which can ensure that there is sufficient contact area and tight connection between the sinking groove 1021 and the positioning portion 201, thereby enhancing the structural stability of the battery cell 1000 and preventing the positioning portion 201 from loosening or falling off in the sinking groove 1021.

[0035] Since the depth b of the sinking groove 1021 is greater than the length a of the positioning portion 201, it can ensure that the positioning portion 201 has enough space in the sinking groove 1021 for accurate positioning. This design can ensure that the positive plate 200 can be correctly aligned and connected, improve the positioning accuracy of the battery cell 1000, and reduce assembly errors.

[0036] In an optional embodiment of the present invention, the battery cell 1000 further includes an adhesive layer, and the adhesive layer is disposed between the insulating layer 300 and the sinking groove 1021 .

[0037] The adhesive layer is located between the insulating layer 300 and the sinking groove 1021, and can provide an additional fixing function. The adhesive layer is sticky and can firmly adhere the positioning part 201 and the insulating layer 300 to the sinking groove 1021, so that the connection between the positioning part 201 and the sinking groove 1021 is tighter, preventing the positive plate 200 from shifting or loosening during use, and maintaining the structural stability of the battery cell 1000.

[0038] The adhesive layer is located between the insulating layer 300 and the sinking groove 1021, providing additional insulation protection. It can fill the gap between the insulating layer 300 and the sinking groove 1021 to prevent external impurities or moisture from penetrating. This design can enhance the insulation performance of the battery cell 1000, reduce the risk of battery short circuit, and improve the safety of the battery cell 1000.

[0039] In an optional embodiment of the present invention, the positive electrode plate 200 is made of aluminum or steel, and the shell 100 is made of steel.

[0040] Aluminum and steel materials both have high strength and stability and can withstand greater pressure and stress. The positive plate 200 made of aluminum or steel has higher structural strength to maintain the structural integrity of the battery cell 1000, so that the battery cell 1000 has higher strength and stability, and improves the durability and reliability of the battery cell 1000. The housing 100 is made of steel material, so that the housing 100 has a strong structural strength and can withstand greater pressure and stress. The steel housing 100 can effectively protect the internal components from external impact and damage, provide higher structural strength for the battery cell 1000, and increase the durability and reliability of the battery cell 1000.

[0041] Specifically, steel materials generally have good sealing properties, and can prevent external moisture, impurities, and chemicals from entering the battery cell 1000. The steel housing 100 can provide effective sealing, and protect the internal components of the battery cell 1000 from moisture and corrosion.

[0042] On the other hand, both aluminum and steel have good corrosion resistance. In the working environment of the battery cell 1000, there may be humidity, chemicals or other corrosive factors. The positive plate 200 made of aluminum or steel and the housing 100 made of steel can effectively resist corrosion and extend the service life of the battery cell 1000.

[0043] On the other hand, aluminum and steel materials have good electrical conductivity. The positive plate 200 plays an important role in current conduction in the battery cell 1000, and its electrical conductivity directly affects the performance and efficiency of the battery cell 1000. The positive plate 200 made of aluminum or steel can provide lower resistance, which helps to reduce energy loss and heat generation.

[0044] In an optional embodiment of the present invention, the thickness of the positive electrode plate 200 is 0.1 mm to 0.2 mm.

[0045] The positive electrode plate 200 with a thickness of 0.1 mm to 0.2 mm is relatively thin. The thinner positive electrode plate 200 can reduce the overall weight of the battery cell 1000, and can effectively reduce the weight of the battery cell 1000, thereby improving the energy efficiency and portability of the device. On the other hand, the thinner positive electrode plate 200 is more convenient for shaping and production, facilitates the formation of the positioning portion 201, and can reduce the production cost to a certain extent. At the same time, the thinner positive electrode plate 200 can reduce the resistance loss of the current on the electrode plate.

[0046] In an optional embodiment of the present invention, the cross section of the battery cell 1000 is circular or rectangular.

[0047] When the cross section of the battery cell 1000 is circular, due to the circular geometric shape, the battery cell 1000 can evenly distribute stress when subjected to force, thereby improving the structural strength and durability of the battery cell 1000. The circular cross section has better thermal conductivity and can provide a larger surface area to volume ratio, which is beneficial to heat conduction and heat dissipation, thereby improving the heat dissipation capacity of the battery cell 1000.

[0048] When the cross section of the battery cell 1000 is rectangular, the rectangular battery cell 1000 has a larger surface area. Under the same volume, the rectangular cross section can provide a larger surface area, which is conducive to the contact between the battery cell 1000 and the electrolyte, and improves the energy storage capacity of the battery cell 1000. The rectangular cross section can more effectively utilize the space of the battery cell 1000, which is particularly suitable for certain devices or applications of specific shapes. The battery cell 1000 with a rectangular cross section can be more easily stacked in parallel and / or assembled in series to form a battery pack with a larger capacity or higher voltage.

[0049] The utility model also discloses a battery pack, comprising a plurality of battery cells 1000 in any of the above embodiments, wherein the plurality of battery cells 1000 are connected in series and / or in parallel.

[0050] The battery pack includes the same structure and benefits as the battery cell 1000 in the aforementioned embodiment. The structure and benefits of the battery cell 1000 have been described in detail in the aforementioned embodiment and will not be repeated here.

[0051] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present utility model rather than to limit it. For those skilled in the art, the technical solutions described in the above embodiments can be modified, or some of the technical features therein can be replaced by equivalents; and all these modifications and replacements should fall within the scope of protection of the claims attached to the present utility model.

Claims

1. A battery cell, characterized in that: include: A shell body, wherein a cavity is formed in the shell body, an opening is provided on one side of the shell body, and a sinking groove is provided at the edge of the opening along the height direction of the shell body; A positive plate, the edge of which is bent toward one side of the shell to form a positioning portion, and the positioning portion is engaged with the sinking groove; an insulating layer, the insulating layer covering the positioning portion to isolate the housing from the positive electrode plate; A winding core is disposed in the cavity, a positive electrode ear of the winding core is connected to the positive electrode plate, and a negative electrode ear of the winding core is connected to the shell.

2. The battery cell according to claim 1, characterized in that: The insulating layer includes a first connecting segment, a second connecting segment, a third connecting segment and a fourth connecting segment that are interconnected, the first connecting segment is attached to the positive electrode plate near the positioning portion, the second connecting segment is attached to a side of the positioning portion facing the cavity, the third connecting segment is attached to a side of the positioning portion that is arranged parallel to the positive electrode plate, and the fourth connecting segment is attached to a side of the positioning portion that is away from the cavity.

3. The battery cell according to claim 1, characterized in that: The length of the positioning portion is a, and the depth of the sinking groove is b, wherein b>a.

4. The battery cell according to claim 2, characterized in that: The width of the positioning portion is c, the thickness of the insulating layer is d, and the width of the sinking groove is e, wherein e>c+2d.

5. The battery cell according to any one of claims 1 to 4, characterized in that: The battery core further includes an adhesive layer, and the adhesive layer is arranged between the insulating layer and the sinking groove.

6. The battery cell according to any one of claims 1 to 4, characterized in that: The positive electrode plate is made of aluminum or steel.

7. The battery cell according to any one of claims 1 to 4, characterized in that: The shell is made of steel.

8. The battery cell according to any one of claims 1 to 4, characterized in that: The thickness of the positive electrode plate is 0.1 mm to 0.2 mm.

9. The battery cell according to any one of claims 1 to 4, characterized in that: The cross section of the battery core is circular or rectangular.

10. A battery pack, characterized in that: The invention comprises a plurality of battery cells according to any one of claims 1 to 9, wherein the plurality of battery cells are connected in series and / or in parallel.

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