Battery cell structure of cylindrical lithium battery

Abstract

The utility model relates to the technical field of inner core structures of lithium batteries, in particular to a battery core structure of a cylindrical lithium battery, which comprises an outer battery core protection body, a through hole is arranged at the center of the outer battery core protection body, a central radiating tube is arranged in an inner cavity of the through hole, a negative plate is sleeved on the surface of the central radiating tube, and a positive plate is arranged on the surface of the negative plate. The surface of one end of the negative plate is fixedly connected with a negative tab, and one side of the negative tab is in spot welding connection with a negative collector plate. The battery has the advantages of heat dissipation, fire prevention and the like for resisting the external severe environment, through the arrangement of the central heat dissipation pipe, rapid conduction and dispersion of heat can be effectively promoted, heat accumulation in the working process of the battery is reduced, the risk of overheating is reduced, and therefore the safety and stability of the battery are improved, and through the arrangement of the compression-resistant damping pieces, the service life of the battery is prolonged. The damage of external impact and pressure to the battery inner core can be effectively reduced, the service life of the battery is prolonged, and the safety and stability of the battery are improved.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery core structure technology, specifically to a cylindrical lithium battery cell structure. Background Technology

[0002] Cylindrical lithium batteries (especially 18650 and 21700 models) are currently the mainstream battery type widely used in portable electronic devices, power tools, electric vehicles, energy storage systems, and other fields. The design and manufacturing technology of their cell structure has a significant impact on the safety, performance, lifespan, and cost of the battery. The optimization and development of cylindrical lithium battery cell structure involves technological advancements in multiple fields, including material innovation, improvements in battery processes, enhanced safety design, and intelligent battery management systems.

[0003] As disclosed in CN222052005U, this is a high-safety cylindrical lithium battery core and lithium battery. The core is made by winding a positive electrode sheet, a separator, and a negative electrode sheet onto a winding needle. A central hole is formed after the winding needle is pulled out from the center of the core. The outermost ring of the core is a copper foil sheet without negative electrode active material coated on either side. If the lithium battery experiences an internal short circuit due to harsh external environments such as high temperature, impact, or combustion, the battery can quickly expel the high-temperature gas carrying heat to the outside of the battery through the central hole, preventing the battery from exploding.

[0004] The aforementioned patent states that although a central hole is designed in the center of the battery to reduce internal pressure, the battery does not have a fireproof layer. The fireproof layer design can effectively isolate heat sources, slow down temperature rise, and prevent the spread of fire. During the use of the battery, a reasonable pressure-resistant buffer layer can effectively disperse external impacts or internal pressure, reduce structural damage caused by collisions or external forces, and avoid dangers such as battery short circuits, overheating, or electrolyte leakage. Utility Model Content

[0005] The purpose of this invention is to provide a cylindrical lithium battery cell structure that has the advantages of heat dissipation, fire prevention, pressure resistance, and shock absorption, thus solving the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a cylindrical lithium battery cell structure, including an outer protective body for the cell, a through hole at the center of the outer protective body, a central heat dissipation pipe disposed within the cavity of the through hole, a negative electrode sheet fitted on the surface of the central heat dissipation pipe, a negative electrode tab fixedly connected to one end of the negative electrode sheet, a negative current collector plate spot-welded to one side of the negative electrode tab, and the central heat dissipation pipe penetrating the surface of the negative current collector plate, a separator sheet fitted on the surface of the negative electrode sheet, one end of the separator sheet fitted on the surface of the negative current collector plate, a positive electrode sheet fitted on the surface of the separator sheet, a positive electrode tab fixedly connected to one end of the positive electrode sheet, a positive current collector plate spot-welded to one side of the positive electrode tab, a pressure-resistant damping sheet fitted on the surface of the positive electrode sheet, a fireproof sheet fitted on the surface of the pressure-resistant damping sheet, and the fireproof sheet disposed on the inner wall of the outer protective body for the cell.

[0007] Furthermore, as a preferred embodiment of this invention, the diaphragm is made of PE / PP composite material, and the inner cavity of the diaphragm has multiple micropores.

[0008] Furthermore, as a preferred embodiment of this utility model, a main body top cover is fixedly connected to the top of the pressure-resistant damping sheet and the fireproof sheet, and a main body bottom cover is fixedly connected to the bottom of the pressure-resistant damping sheet and the fireproof sheet.

[0009] Furthermore, as a preferred embodiment of this utility model, the bottom of the negative electrode sheet and the bottom of the negative electrode current collector are fixedly connected to a negative electrode bottom cover, and the bottom of the diaphragm sheet and the bottom of the negative electrode bottom cover are both provided with a liquid injection port.

[0010] Furthermore, as a preferred embodiment of this invention, the surface of the outer protective body of the battery cell is provided with anti-slip texture.

[0011] Beneficial effects: The technical solution of this application has the following technical effects: This utility model has the advantages of heat dissipation and fire prevention against harsh external environments. Through the setting of the central heat dissipation pipe, it can effectively promote the rapid conduction and dispersion of heat, reduce the heat accumulation of the battery during operation, reduce the risk of overheating, and thus improve the safety and stability of the battery. Through the setting of the anti-pressure and shock-absorbing sheet, it can effectively reduce the damage to the battery core caused by external impact and pressure, extend the battery life, and improve the safety and stability of the battery. Especially in the environment of high vibration and frequent impact, the anti-pressure and shock-absorbing sheet can ensure the normal operation of the battery, reduce the occurrence of damage and failure, and thus improve the reliability of the entire device. Through the setting of the fireproof sheet, it can play a physical isolation role, isolating the high-temperature part inside the battery from the external environment. When an abnormal reaction occurs inside the battery, the fireproof sheet can slow down the spread of heat and fire source, reducing the threat to the external components of the battery and the surrounding environment.

[0012] It should be understood that all combinations of the foregoing concepts and the additional concepts described in more detail below can be considered as part of the utility model subject matter of this disclosure, provided that such concepts do not contradict each other. Attached Figure Description

[0013] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0015] Figure 2 This is a schematic diagram of the protective structure at the top of the battery core of this utility model;

[0016] Figure 3 This is a schematic diagram of the internal structure at the top of the battery core of this utility model;

[0017] Figure 4 This is a schematic diagram of the bottom protective structure of the battery core of this utility model. Figure 1 ;

[0018] Figure 5 This is a schematic diagram of the bottom protective structure of the battery core of this utility model. Figure 2 ;

[0019] Figure 6 This is a schematic diagram of the internal structure at the bottom of the battery core of this utility model.

[0020] The meanings of the labels in the diagram are as follows: 1. Outer protective body of the battery cell; 2. Central heat dissipation tube; 3. Negative electrode plate; 4. Negative electrode tab; 5. Negative electrode current collector; 6. Diaphragm plate; 7. Positive electrode plate; 8. Positive electrode tab; 9. Positive electrode current collector; 10. Pressure-resistant and shock-absorbing sheet; 11. Fireproof sheet; 12. Main body top cover; 13. Main body bottom cover; 14. Negative electrode bottom cover; 15. Liquid injection port. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings. To better understand the technical content of the present utility model, specific embodiments are provided and described in conjunction with the accompanying drawings. Various aspects of the present utility model are described in this disclosure with reference to the accompanying drawings, which show many illustrative embodiments. It should be understood that the various concepts and embodiments described above, as well as those described in more detail below, can be implemented in any of many ways. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0022] As attached Figure 1 To be continued Figure 6 As shown: This embodiment provides a cylindrical lithium battery cell structure, including an outer protective body 1. A through hole is provided at the center of the outer protective body 1. A central heat dissipation pipe 2 is provided in the inner cavity of the through hole. A negative electrode plate 3 is sleeved on the surface of the central heat dissipation pipe 2. A negative electrode tab 4 is fixedly connected to one end of the surface of the negative electrode plate 3. A negative current collector plate 5 is spot-welded to one side of the negative electrode tab 4. The central heat dissipation pipe 2 penetrates the surface of the negative current collector plate 5. A separator 6 is sleeved on the surface of the negative electrode plate 3. One end of the separator 6 is sleeved on the surface of the negative current collector plate 5. A positive electrode plate 7 is sleeved on the surface of the separator 6. A positive electrode tab 8 is fixedly connected to one end of the positive electrode plate 7. A positive current collector plate 9 is spot-welded to one side of the positive electrode tab 8. A pressure-resistant damping sheet 10 is sleeved on the surface of the positive electrode plate 7. A fireproof sheet 11 is sleeved on the surface of the pressure-resistant damping sheet 10. The fireproof sheet 11 is disposed on the inner wall of the outer protective body 1.

[0023] Specifically, the diaphragm 6 is made of PE / PP composite material, and the inner cavity of the diaphragm 6 has multiple micropores.

[0024] In this embodiment: the multiple micropores in the inner cavity of the diaphragm 6 facilitate electrolyte penetration, making ion transport inside the battery smoother, thereby improving the charging and discharging efficiency of the battery. The porous structure can enhance the thermal management capability of the battery and reduce the risk of overheating. The diaphragm 6 is made of, but is not limited to, PE / PP composite material, which can provide good thermal stability and mechanical strength.

[0025] Specifically, the top of the compression damping sheet 10 and the fireproof sheet 11 are fixedly connected to the main body top cover 12, and the bottom of the compression damping sheet 10 and the fireproof sheet 11 are fixedly connected to the main body bottom cover 13.

[0026] In this embodiment: the combined use of the main body top cover 12 and the main body bottom cover 13 protects the anti-pressure damping sheet 10 and the fireproof sheet 11, provides physical support for the battery, enhances the overall structural stability of the battery, ensures that the anti-pressure damping sheet 10 and the fireproof sheet 11 are not easily deformed or damaged during use, and prevents structural displacement or damage caused by mechanical impact.

[0027] Specifically, the bottom of the negative electrode sheet 3 and the bottom of the negative electrode current collector 5 are fixedly connected to the negative electrode bottom cover 14, and the bottom of the diaphragm sheet 6 and the bottom of the negative electrode bottom cover 14 are both provided with a liquid injection port 15.

[0028] In this embodiment: the negative electrode bottom cover 14 can protect the negative electrode plate 3 and the negative electrode current collector 5, preventing dust, moisture and other environmental factors from entering the battery, thereby improving the battery's durability and safety. The electrolyte injection port 15 allows users to easily inject electrolyte into the battery.

[0029] Specifically, the surface of the outer protective body 1 of the battery cell is provided with anti-slip texture.

[0030] In this embodiment: by setting anti-slip texture, the friction with fingers can be increased, providing a better grip and preventing slippage.

[0031] The working principle and usage process of this utility model are as follows: During battery use, a through hole is opened inside the outer protective body 1 of the battery cell. A central heat dissipation pipe 2 is fixedly connected to the inner cavity of the through hole. When air pressure is generated inside the battery cell, the air pressure enters the central heat dissipation pipe 2 and is then discharged to the outside of the battery cell body, reducing the possibility of battery cell explosion. Multiple micropores are opened in the inner cavity of the separator 6. The porous structure facilitates the penetration of electrolyte, making the ion transport inside the battery smoother, thereby improving the charging and discharging efficiency of the battery. The porous structure can enhance the thermal management capability of the battery and reduce the risk of overheating. The separator 6 is made of, but is not limited to, PE / PP composite material, which can provide good thermal stability and mechanical strength. A pressure-resistant damping plate 10 is fixedly connected to the outer layer of the positive electrode tab 8 of the battery cell. The pressure-resistant damping plate 10 can effectively protect the battery from external impact and pressure damage, extend the battery life, and improve the safety and stability of the battery, especially under high vibration and frequent charging. In an environment with shocks, the role of the pressure-resistant damping sheet 10 becomes more pronounced, preventing the battery from exploding due to external influences. A fireproof sheet 11 is installed on the outer layer of the pressure-resistant damping sheet 10. The fireproof sheet 11 isolates the high-temperature part inside the battery from the external environment, reducing the impact of overheating on the battery core. A main body top cover 12 and a main body bottom cover 13 are installed at both ends of the battery core. One is to protect the stability of the pressure-resistant damping sheet 10 and the fireproof sheet 11, and the other is to provide physical support and stability for the battery when it is placed. A negative electrode bottom cover 14 is fixedly connected to the bottom of the negative electrode sheet 3 and the negative electrode current collector 5. The negative electrode bottom cover 14 is mainly used to protect the negative electrode sheet 3, the negative electrode current collector 5 and the separator sheet 6, preventing dust and other objects from entering the negative electrode sheet 3 and the negative electrode current collector 5. The bottom of the separator sheet 6 and the negative electrode bottom cover 14 are both provided with an injection port 15. The injection port 15 is mainly used to facilitate the injection of electrolyte into the inner cavity of the separator sheet 6.

[0032] It should be noted that in this paper, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0033] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Those skilled in the art to which this invention pertains can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of this invention shall be determined by the claims.

Claims

1. A cylindrical lithium battery cell structure comprising a cell outer protection body (1), characterized in that: The center of the outer protection body (1) of the battery cell is provided with a through hole, and the inner cavity of the through hole is provided with a center heat dissipation pipe (2), the surface of the center heat dissipation pipe (2) is sleeved with a negative plate (3), one end of the surface of the negative plate (3) is fixedly connected with a negative tab (4), one side of the negative tab (4) is spot-welded with a negative current collector plate (5), and the center heat dissipation pipe (2) penetrates the surface of the negative current collector plate (5), the surface of the negative plate (3) is sleeved with a diaphragm (6), one end of the diaphragm (6) is sleeved on the surface of the negative current collector plate (5), the surface of the diaphragm (6) is sleeved with a positive plate (7), one end of the positive plate (7) is fixedly connected with a positive tab (8), one side of the positive tab (8) is spot-welded with a positive current collector plate (9), the surface of the positive plate (7) is sleeved with a pressure-resistant shock-absorbing sheet (10), the surface of the pressure-resistant shock-absorbing sheet (10) is sleeved with a fireproof sheet (11), and the fireproof sheet (11) is arranged on the inner wall of the outer protection body (1) of the battery cell.

2. The battery cell structure of claim 1, wherein: The diaphragm (6) is made of PE / PP composite material, and a plurality of micropores are arranged in the inner cavity of the diaphragm (6).

3. The battery cell structure of cylindrical lithium battery according to claim 1, wherein: The top of the pressure-resistant shock-absorbing sheet (10) and the fireproof sheet (11) is fixedly connected with a main body top cover (12), and the bottom of the pressure-resistant shock-absorbing sheet (10) and the fireproof sheet (11) is fixedly connected with a main body bottom cover (13).

4. The battery cell structure of cylindrical lithium battery according to claim 1, wherein: The bottom of the negative plate (3) and the negative current collector plate (5) is fixedly connected with a negative bottom cover (14), and the bottom of the diaphragm (6) and the negative bottom cover (14) is provided with a liquid injection port (15) together.

5. The battery cell structure of cylindrical lithium battery according to claim 1, wherein: The surface of the outer protection body (1) of the battery cell is provided with anti-skid lines.

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