A high power lithium battery

Abstract

The utility model discloses a high -power lithium cell, including battery case, the inside of battery case is provided with electric core, and the surface of electric core is arranged with positive material piece, and the inside fixed mounting of battery case has the heat conduction strip, and the top surface embedding of battery case installs the jump protection switch, and the surface of jump protection switch is equipped with negative plate, and the periphery is equipped with a plurality of current collector piece, and is connected in parallel through current collector piece and a plurality of electric core, and the bottom of positive material piece is equipped with a plurality of electrode ear and the inside electric connection of battery case forms battery positive pole. The electric core is arranged in the form of circle or array along the inside of battery case, and the positive material piece is distributed around and adopts double -sided coating symmetrical composite structure, and the bottom extension forms a plurality of electrode ear, and the uniformity of current collection is improved. The structure realizes the high -power output of multiple electric core parallel connection, and the internal resistance is reduced in combination with the winding pole piece and the multiple electrode ear design, and the thermal stability and safety of battery are improved with the heat conduction and protection structure, and the service life is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, specifically a high-power lithium battery. Background Technology

[0002] Lithium-ion batteries, as the primary form of power batteries and energy storage systems, are widely used in electric vehicles, portable electronic devices, and high-power power supplies. As applications evolve towards higher power and higher rate capabilities, batteries face increased current loads and thermal management pressures during charging and discharging. Existing single-cell lithium-ion batteries typically employ a series connection or a small number of parallel connections. Under high current input and output conditions, this can easily lead to excessively high current density in individual cells, resulting in increased internal resistance, concentrated heat generation, and insufficient power output, making it difficult to meet the demands of high-rate applications.

[0003] Regarding the positive electrode structure, most common battery positive electrode sheets employ a single-sided or asymmetrical coating structure, led out through a single tab. This design, after winding and forming, leads to uneven current collection paths, excessively high local current density, increased internal resistance losses, and makes the electrode prone to current bias and localized heating during operation. Especially during high-rate discharge, the single-tab structure cannot effectively disperse the current, easily causing excessively rapid overall battery temperature rise and accelerated capacity decay.

[0004] Therefore, existing lithium batteries generally suffer from the following shortcomings in structural design: First, a single cell bears an excessively large current load, limiting the overall input and output power; second, the positive electrode structure is too simple, with insufficient tabs, resulting in limited current collection paths, uneven current distribution, and difficulty in ensuring battery stability and lifespan under high-power conditions. These problems have become significant bottlenecks restricting the realization of high-power, long-life applications of lithium batteries, urgently requiring a new design scheme with optimized cell and electrode structures for improvement. Utility Model Content

[0005] This utility model aims to solve one of the technical problems existing in the prior art or related technologies.

[0006] Therefore, the technical solution adopted by this utility model is as follows: a high-power lithium battery, comprising a battery casing, a battery cell, a positive electrode sheet, a heat-conducting strip, a trip protection switch, a negative electrode sheet, a current collector, and electrode tabs. The battery cell is disposed inside the battery casing, the positive electrode sheet is arranged on the surface of the battery cell, the heat-conducting strip is fixedly installed on the inner side of the battery casing, the trip protection switch is embedded in the top surface of the battery casing and is connected to the battery cell through the negative electrode sheet and the current collector to form a circuit, and the bottom end of the positive electrode sheet has several electrode tabs that are electrically connected to the inner side of the battery casing to form a positive electrode. Through the above combination, the battery cells can work in parallel and have good heat dissipation and protection capabilities, thereby achieving safe and stable high-current charging and discharging.

[0007] In a preferred embodiment, the cells are further configured such that they are arranged circumferentially or in an array along the inner side of the battery casing, with positive electrode sheets distributed around the outer circumference of the cells, and heat-conducting strips extending along the thickness direction of the positive electrode sheets. This structural arrangement results in more uniform current collection, and the heat-conducting strips form a longitudinal heat conduction path, enabling rapid transfer of heat from the cells to the battery casing, specifically reducing the local temperature rise of the battery during high-rate discharge.

[0008] In a preferred embodiment, the positive electrode sheet is further configured such that: the positive electrode sheet includes a conductive film, both sides of which are uniformly coated with a positive electrode active material layer, and the film is integrally pressed to form a symmetrical composite structure; the bottom end of the conductive film extends to form multiple electrode tabs, which are spaced apart along the length of the conductive film. This structure facilitates the winding process, shortens and disperses the current path, and specifically improves the current collection efficiency and reduces the internal resistance.

[0009] In a preferred embodiment, the heat-conducting strip is further configured as follows: it is a sheet or strip structure made of graphite sheet or a high thermal conductivity composite material, and is thermally bonded to the inner wall of the battery casing. This structure improves thermal conductivity, specifically ensuring uniform heat dissipation and thermal management stability of the battery during high-power operation.

[0010] In a preferred embodiment, the trip protection switch is further configured such that it is mounted at the center of the top of the cell and electrically connected to the negative electrode and current collector. This configuration provides circuit protection under abnormal battery conditions, specifically enhancing the battery's safety and reliability during high-power cycling.

[0011] In a preferred embodiment, the current collector and the trip protection switch are integrated into one piece, and the outer surface of the current collector is fitted with an insulating sleeve that isolates it from the positive electrode plate. This design ensures stable circuit conduction while avoiding short circuits between components of different polarities, thereby improving the electrical safety of the battery during operation.

[0012] In a preferred embodiment, the space between the inner wall of the battery casing and the heat-conducting strip is further configured such that a thermally conductive adhesive layer is filled to enhance the adhesion between the heat-conducting strip and the casing and reduce contact thermal resistance. This specifically enables rapid heat transfer from the battery cell to the casing, improving the overall heat dissipation effect.

[0013] The beneficial effects achieved by this utility model are as follows: 1. In this utility model, the battery cells achieve a multi-cell parallel structure through current collectors and a snap-on protection switch, which can effectively distribute the current load of a single battery cell, significantly reduce internal resistance, and improve the overall battery input and output power, making it suitable for high-rate charging and discharging scenarios.

[0014] 2. In this utility model, the positive electrode sheet is formed by winding. The positive electrode active material layer is uniformly coated on both sides of the conductive film and pressed to form a symmetrical composite structure. Multiple electrode ears are set at the bottom and distributed at intervals along the length direction, which can reduce the current collection path impedance and improve the current distribution uniformity, thereby further improving the rate performance and cycle life. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the present utility model; Figure 2 This is a schematic diagram of the connection structure between the battery cell and the trip protection switch according to one embodiment of the present invention; Figure 3 This is a cross-sectional structural diagram of one embodiment of the present invention; Figure 4 This is a schematic diagram of the positive electrode material structure according to an embodiment of the present invention.

[0016] Figure label: 100. Battery casing; 110. Battery cell; 120. Positive electrode sheet; 130. Heat-conducting strip; 121. Electrode tab; 200. Trip protection switch; 210. Negative electrode plate; 220. Current collector plate. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features of the present utility model can be combined with each other.

[0018] It should be understood that these descriptions are merely exemplary and not intended to limit the scope of this invention.

[0019] The following describes, with reference to the accompanying drawings, some embodiments of a high-power lithium battery provided by this utility model.

[0020] Combination Figures 1-4As shown, this utility model provides a high-power lithium battery, including a battery casing 100, a battery cell 110 disposed inside the battery casing 100, and a positive electrode sheet 120 disposed on the surface of the battery cell 110. A heat-conducting strip 130 is fixedly installed on the inner side of the battery casing 100 to conduct heat out of the battery cell 110 and transfer it to the battery casing 100 during operation. A trip protection switch 200 is embedded in the top surface of the battery casing 100. A negative electrode sheet 210 is provided on the surface of the trip protection switch 200, and several current collectors 220 are provided on the outer periphery of the trip protection switch 200, which are connected in parallel with multiple battery cells 110. Several electrode tabs 121 are provided at the bottom end of the positive electrode sheet 120, and the electrode tabs 121 are electrically connected to the inner side of the battery casing 100, thereby forming the positive electrode structure of the battery.

[0021] In a preferred embodiment, the battery cells 110 are arranged circumferentially or in an array along the inner side of the battery casing 100. The positive electrode sheets 120 are distributed around the outer peripheral surface of the battery cells 110 to ensure uniform current collection. The heat-conducting strip 130 extends along the thickness direction of the positive electrode sheets 120, so that the heat generated by the battery cells 110 during charging and discharging can be transferred to the battery casing 100 in a timely manner through the heat-conducting strip 130, thereby reducing the temperature gradient inside the battery.

[0022] In another embodiment, the positive electrode sheet 120 includes a conductive film. The conductive film is uniformly coated with a positive electrode active material layer on both sides and is integrally pressed to form a symmetrical composite structure, thereby ensuring balanced current collection on both sides. Multiple electrode tabs 121 extend from the bottom end of the conductive film, and the electrode tabs 121 are spaced apart along the length of the conductive film, shortening the current path and dispersing the current density, further reducing internal resistance.

[0023] In another embodiment, the heat-conducting strip 130 is a sheet or strip structure, and its material is selected from graphite sheets or high thermal conductivity composite materials. The heat-conducting strip 130 is thermally bonded to the inner wall of the battery casing 100, thereby improving the heat conduction efficiency. This structure can quickly conduct the heat generated inside the cell 110 to the battery casing 100, ensuring the thermal stability of the battery during high-rate operation.

[0024] In another embodiment, the trip protection switch 200 is installed at the top center of the battery cell 110, and is electrically connected to the negative electrode 210 and the current collector 220. When the battery is under abnormal operating conditions, the trip protection switch 200 can provide disconnection protection, and in conjunction with the fast conductivity characteristics of the current collector 220, it improves the stability of the overall circuit.

[0025] In another embodiment, the current collector 220 and the trip protection switch 200 are integrally formed, resulting in a compact structure and stable connection. An insulating sleeve is fitted onto the outer surface of the current collector 220 to isolate it from the positive electrode plate 120, thus avoiding the risk of short circuits that may occur between components of different polarities.

[0026] In another embodiment, a thermally conductive adhesive layer is filled between the inner wall of the battery casing 100 and the thermally conductive strip 130. This thermally conductive adhesive layer not only improves the fit between the thermally conductive strip 130 and the battery casing 100, but also further reduces contact thermal resistance, thereby enhancing the overall heat dissipation effect of the battery cell 110.

[0027] During the operation of this invention, the heat generated by the battery cell 110 during high-rate charging and discharging is conducted to the battery casing 100 via the positive electrode sheet 120 and the heat-conducting strip 130, and the heat dissipation efficiency is improved by the thermally conductive adhesive layer, thereby achieving thermal balance of the battery. The connection between the trip protection switch 200, the negative electrode sheet 210, and the current collector 220 enables multiple battery cells 110 to form a parallel structure, improving the power output capability of the battery. The positive electrode sheet 120 adopts a double-sided coated symmetrical composite structure and has multiple electrode tabs 121 arranged at the bottom end, making the current collection more uniform, reducing resistance, and improving the reliability and service life of the battery under high-power operating conditions.

[0028] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0029] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A high-power lithium battery, characterized in that, The battery includes a battery housing (100), a battery cell (110) disposed inside the battery housing (100), and a positive electrode sheet (120) arranged on the surface of the battery cell (110). A heat-conducting strip (130) is fixedly installed on the inner side of the battery housing (100). A trip protection switch (200) is embedded in the top surface of the battery housing (100), and a negative electrode sheet (210) is provided on the surface of the trip protection switch (200). Several current collectors (220) are provided on the outer periphery of the trip protection switch (200), and the current collectors (220) are connected in parallel with multiple battery cells (110). Several electrode ears (121) are provided at the bottom end of the positive electrode sheet (120) for electrical connection with the inner side of the battery housing (100) to form the positive electrode of the battery.

2. The high-power lithium battery according to claim 1, characterized in that, The battery cell (110) is arranged in a circular or array pattern along the inner side of the battery casing (100), the positive electrode sheet (120) is distributed around the outer circumference of the battery cell (110), and the heat-conducting strip (130) extends along the thickness direction of the positive electrode sheet (120).

3. The high-power lithium battery according to claim 1, characterized in that, The positive electrode sheet (120) includes a conductive film, on both sides of which a positive active material layer is uniformly coated and integrally pressed to form a symmetrical composite structure; the bottom end of the conductive film extends to form a plurality of electrode ears (121), which are spaced apart along the length of the conductive film.

4. The high-power lithium battery according to claim 1, characterized in that, The heat-conducting strip (130) is a sheet or strip structure, made of graphite sheet or high thermal conductivity composite material, and is thermally bonded to the inner wall of the battery casing (100).

5. The high-power lithium battery according to claim 1, characterized in that, The trip protection switch (200) is installed at the top center of the cell (110) and is electrically connected to the negative electrode (210) and the current collector (220).

6. The high-power lithium battery according to claim 1, characterized in that, The current collector (220) and the trip protection switch (200) are integrally formed, and the outer surface of the current collector (220) is fitted with an insulating sleeve layer that is isolated from the positive electrode sheet (120).

7. The high-power lithium battery according to claim 1, characterized in that, A thermally conductive adhesive layer is filled between the inner wall of the battery housing (100) and the thermally conductive strip (130).

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