Cylindrical lithium battery with reinforcing ribs

Abstract

The utility model discloses a cylindrical lithium battery with reinforcing ribs, which comprises a positive terminal assembly, a negative terminal assembly and a battery pole group, the positive terminal assembly comprises a cap, a positive insulation pad and a positive current collector, and the negative terminal assembly comprises a negative insulation pad, a negative current collector and a battery shell. A reinforcing rib with a groove path is arranged on the battery shell, and the battery pole group is arranged in the battery shell. By arranging the reinforcing rib structure with the groove, the structural strength and the bearing capacity of the shell are enhanced, the shell is not easy to deform and crack, the risk of thermal runaway of the side surface of the shell is reduced, the contact area is also increased, the temperature of the battery pack can be better controlled, and the risk of high-temperature runaway is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, in particular to a cylindrical lithium battery with reinforcing ribs. Background Art

[0002] With the widespread use of lithium-ion batteries, the safety of lithium batteries has also received attention. A single cell of a lithium battery can trigger thermal runaway due to temperature rise or mechanical damage, leading to the risk of loss of control of the entire battery pack. In order to control thermal runaway, existing cylindrical lithium batteries are mainly improved by adding explosion-proof lines at the bottom of the steel shell and improving the CID structure of the cap. If the depth of the line at the bottom of the steel shell is too deep, the battery will be at risk of leakage, and if the depth is too shallow, it will affect the rapid pressure relief after loss of control; if the structural strength of the CID structure of the cap is too strong, it will affect the speed of its CID rupture, causing the risk of thermal runaway. The present application improves the battery shell, strengthens the structural strength and stability of the shell body, and avoids the risk of battery pack loss of control due to loss of control of the shell body. Utility Model Content

[0003] The utility model aims to overcome the shortcomings of the prior art and provide a cylindrical lithium battery with reinforcing ribs.

[0004] The purpose of the utility model is achieved through the following technical scheme: a cylindrical lithium battery with reinforcing ribs, comprising a positive terminal assembly, a negative terminal assembly and a battery electrode group, the positive terminal assembly comprising a cap, a positive electrode insulating pad and a positive electrode collector, the negative terminal assembly comprising a negative electrode insulating pad, a negative electrode collector and a battery shell, the battery shell is provided with reinforcing ribs with grooves, and the battery electrode group is arranged inside the battery shell.

[0005] A further technical solution is that the battery shell is made of a steel shell, and after the steel shell has been subjected to a forming process and a post-processing process, it is subjected to a grooving process to form a reinforcing rib structure with a groove path.

[0006] A further technical solution is that the battery electrode group is finished with a separator or a negative electrode metal foil.

[0007] A further technical solution is that the number of the reinforcing ribs is 2-5, the groove depth of the reinforcing ribs is 0.1-0.5 mm, and the width is 0.2-1.0 mm.

[0008] A further technical solution is that the positive electrode insulating pad is arranged between the cap and the positive electrode current collector, and the negative electrode insulating pad is arranged between the battery electrode group and the negative electrode current collector.

[0009] The utility model has the following advantages:

[0010] The utility model forms a reinforcing rib structure with a groove in the battery shell, thereby enhancing the structural strength and bearing capacity of the shell, making it less likely to deform, crack or break when subjected to external force, thereby enhancing the strength of the side wall and reducing the risk of thermal runaway on the side. In the heat dissipation system of the battery pack, the contact area is also increased, which facilitates better control of the temperature of the battery pack and reduces the risk of high-temperature runaway. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the exploded structure of the cylindrical lithium battery in the utility model;

[0012] Figure 2 It is a cross-sectional structure of the battery housing in the utility model and a partial schematic diagram at A;

[0013] Figure 3 It is a schematic cross-sectional view of the cylindrical lithium battery in the utility model.

[0014] In the figure, 1. cap; 2. positive electrode insulating pad; 3. positive electrode current collector; 4. battery electrode group; 5. negative electrode insulating pad; 6. negative electrode current collector; 7. battery case. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0016] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0017] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0018] like Figures 1 to 3As shown, a cylindrical lithium battery with reinforcing ribs comprises a positive terminal assembly, a negative terminal assembly and a battery electrode group 4, wherein the positive terminal assembly comprises a cap 1, a positive electrode insulating pad 2 and a positive electrode collector 3, the battery can adopt a conventional cap 1 structure or a rivet structure, and the battery electrode group 4 is connected through the positive electrode collector 3, the negative terminal assembly comprises a negative electrode insulating pad 5, a negative electrode collector 6 and a battery shell 7, the battery electrode group 4 is arranged inside the battery shell 7, and the battery shell 7 is provided with reinforcing ribs with grooves, and the structural strength and stability of the shell are enhanced by the arrangement of the reinforcing ribs. When the battery encounters an abnormal situation or loses control during use, there is sufficient strength to keep the shell intact, so that the battery is depressurized from the top and bottom, which effectively reduces the risk of losing control of the battery pack due to loss of control of the shell.

[0019] In this embodiment, the battery shell 7 is made of steel shell. After the forming process and post-processing process, the steel shell is subjected to a grooving process to form a reinforcing rib structure with grooves, thereby enhancing the structural strength and bearing capacity of the steel shell body, making it less likely to deform, crack or break when subjected to external force; after the battery cell produces gas uncontrollably, the gas generated inside the battery will impact the upper and lower and side walls of its structure, and the presence of the reinforcing ribs will enhance the strength of the side walls and reduce the risk of side loss of control; the battery shell 7 has grooves on the outside, which increases the external contact area, and facilitates better temperature control compared to traditional shells.

[0020] In this embodiment, the battery electrode group 4 is terminated by a diaphragm or a negative electrode metal foil. Specifically, the battery electrode group 4 is composed of a positive electrode material, a positive electrode metal foil, a negative electrode material, a negative electrode metal foil and a diaphragm, and becomes a cylindrical electrode group after the electrode sheet forming and winding process. When the diaphragm is terminated, the side wall of the battery electrode group 4 and the inner wall of the steel shell do not generate contact internal resistance, which is convenient for maintaining the uniformity of the performance of the battery cell.

[0021] In this embodiment, the number of the reinforcing ribs is 2-5, and too many ribs are avoided to increase the stress distribution inside the steel shell and reduce its structural strength and stability. The groove depth a of the reinforcing ribs is in the range of 0.1-0.5 mm, and the width b is in the range of 0.2-1.0 mm. Within this size range, the reinforcing ribs will not occupy much space inside the battery. While fully playing their role, the internal space utilization is guaranteed, and the ductility and brittleness of the steel shell material itself are avoided to be affected by excessive size.

[0022] In this embodiment, the positive electrode insulating pad 2 is arranged between the cap 1 and the positive electrode current collector 3, and the negative electrode insulating pad 5 is arranged between the battery electrode group 4 and the negative electrode current collector 6 to avoid one end contacting the other end of the opposite polarity when in use. After the battery is assembled and injected with electrolyte, the preparation of a cylindrical lithium-ion battery cell is completed. The positive electrode current collector 3 in this application can be selected from industrial pure aluminum or aluminum-manganese alloy, aluminum-magnesium alloy and other materials, and the negative electrode current collector 6 shell can be selected from nickel, copper-nickel composite and other materials. The insulating pad can be made of polypropylene PP, polybutylene terephthalate PBT, soluble polytetrafluoroethylene PFA, polyphenylene sulfide PPS or other insulating and electrolyte corrosion-resistant materials and modified materials for punching or injection molding.

[0023] The implementation principle of the utility model is as follows: the utility model proposes a cylindrical lithium battery with reinforcing ribs, and a reinforcing rib structure with grooves is formed on the surface of the battery shell 7 through a grooving process, which greatly enhances the structural strength and bearing capacity, effectively reduces the risk of side runaway of the battery, and at the same time increases the contact area, improves the heat dissipation capacity, facilitates better temperature control of the battery module, and reduces the risk of thermal runaway.

[0024] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A cylindrical lithium battery with reinforcing ribs, comprising a positive terminal assembly, a negative terminal assembly and a battery electrode group (4), characterized in that: The positive terminal assembly comprises a cap (1), a positive electrode insulating pad (2) and a positive electrode current collector (3); the negative terminal assembly comprises a negative electrode insulating pad (5), a negative electrode current collector (6) and a battery casing (7); the battery casing (7) is provided with reinforcing ribs with grooves; and the battery electrode group (4) is arranged inside the battery casing (7).

2. A cylindrical lithium battery with reinforcing ribs according to claim 1, characterized in that: The battery housing (7) is made of a steel shell, which is subjected to a forming process and a post-processing process, and then a groove rolling process to form a reinforcing rib structure with grooves.

3. A cylindrical lithium battery with reinforcing ribs according to claim 1, characterized in that: The battery electrode group (4) is finished by using a separator or a negative electrode metal foil.

4. A cylindrical lithium battery with reinforcing ribs according to claim 1, characterized in that: The number of the reinforcing ribs is 2-5, the groove depth of the reinforcing ribs is 0.1-0.5mm, and the width is 0.2-1.0mm.

5. A cylindrical lithium battery with reinforcing ribs according to claim 1, characterized in that: The positive electrode insulating pad (2) is arranged between the cap (1) and the positive electrode current collector (3), and the negative electrode insulating pad (5) is arranged between the battery electrode group (4) and the negative electrode current collector (6).

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