A lithium ion battery pack heat dissipation structure

Abstract

The utility model discloses a lithium ion battery pack heat dissipation structure, from inside to outside includes successively: battery pack, it is composed of multiple even distribution's electric core, series parallel board, it is located battery pack's both sides for connecting the electrode of same side electric core, heat conduction board subassembly, it covers the surface of two series parallel board away from battery pack, bucket body, with heat conduction board close adhesion, and will battery pack, series parallel board, heat conduction board cover in, wherein, series parallel board, heat conduction composite board, heat conduction board and bucket body constitute the heat transfer path of heat transfer from electric core to external environment. Compared with prior art, the utility model's advantage lies in, through the construction one multilayer, big contact area, from inside to outside's solid heat conduction path, heat can be active, efficient, even export, avoided the accumulation of heat in the interior, realized the synergic promotion of heat dissipation efficiency, battery safety and service life.

Description

Technical Field

[0001] This utility model relates to the field of battery heat dissipation technology, and in particular to a heat dissipation structure for a lithium-ion battery pack. Background Technology

[0002] Lithium-ion batteries are widely used in electric vehicles, energy storage systems, and portable electronic devices due to their high energy density, long cycle life, and low self-discharge rate. As application scenarios increasingly demand higher power density and longer driving range, lithium-ion battery packs are gradually developing towards higher capacity and higher rate operation. However, during high-rate charging and discharging, the internal electrochemical reactions and internal resistance heating of the battery lead to a significant accumulation of heat. If this heat cannot be dissipated effectively and in a timely manner, it will severely impact battery performance, lifespan, and safety.

[0003] Traditional lithium-ion battery packs primarily rely on two methods for heat dissipation: natural airflow and simple heat sinks on the battery pack casing. The first method depends on natural airflow through the limited gaps within the battery pack to carry heat away. However, the tightly packed cylindrical cells in this structure result in small gaps, significantly limiting airflow and hindering heat dissipation from the core areas. The second method, using only simple heat sinks on the casing, suffers from insufficient contact area between the sinks and the heat source, causing heat to accumulate inside the battery pack. This prevents the heat from being evenly and effectively collected and transferred to the outside, significantly reducing the effectiveness of the external cooling system and ultimately impacting the overall performance and safety of the battery pack. Utility Model Content

[0004] This invention addresses the problems of insufficient contact area between the heat source and the heat dissipation structure of traditional batteries, low heat dissipation efficiency, and uneven heat dissipation. The technical problem to be solved by this invention is to provide a novel heat dissipation structure that can efficiently collect and dissipate heat from the inside of a cylindrical lithium-ion battery pack.

[0005] The technical solution adopted by this utility model to solve the above-mentioned technical problem is: a heat dissipation structure for a lithium-ion battery pack, characterized in that it comprises, from the inside to the outside, the following: A battery pack consists of multiple evenly distributed battery cells; The series-parallel connection plate is located on both sides of the battery pack and is used to connect the electrodes of the cells on the same side and transfer heat. The heat-conducting plate assembly covers the surface of the two parallel plates away from the battery pack and absorbs heat from the parallel plates and the battery cells. The barrel body fits tightly against the heat-conducting plate assemblies on both sides of the battery pack, and houses the battery pack, series and parallel plates, and heat-conducting plate assemblies inside. The series-parallel plates, heat-conducting plate assembly, and barrel body constitute the heat transfer path from the battery cell to the external environment.

[0006] A further preferred embodiment of this utility model is: the heat-conducting plate assembly includes a heat-conducting composite plate and a heat-conducting plate, the heat-conducting composite plate is sandwiched between the series-parallel plate and the heat-conducting plate, and both sides of the heat-conducting composite plate are tightly attached to the series-parallel plate and the heat-conducting plate respectively.

[0007] A further preferred embodiment of this utility model is: the heat-conducting plate assembly is a single heat-conducting composite plate or a single heat-conducting plate, the heat-conducting composite plate or heat-conducting plate covers and adheres to the outer surface of two parallel plates, and is attached to the inner wall of the barrel.

[0008] A further preferred embodiment of this utility model is as follows: the heat-conducting plate is a metal plate, graphene heat dissipation plate, ceramic plate or composite material plate with high thermal conductivity, and the barrel body is a metal barrel with high thermal conductivity or a high-strength composite material barrel with high thermal conductivity.

[0009] A further preferred embodiment of this utility model is: the series-parallel connection board is provided with an interface that mates with each battery cell, and the series-parallel connection board is connected to the battery cells through the interface.

[0010] A further preferred embodiment of this utility model is that the series-parallel plates are metal substrates or ceramic substrates with high thermal conductivity.

[0011] A further preferred embodiment of this utility model is: the heat-conducting plate is provided with at least one outwardly protruding heat dissipation bump on the side away from the battery pack, and the outer end face of the heat dissipation bump is in contact with the inner wall of the barrel.

[0012] A further preferred embodiment of this utility model is that the heat dissipation bumps are arranged along the length direction of the heat-conducting plate.

[0013] A further preferred embodiment of this utility model is as follows: each of the four inner walls of the barrel is provided with heat dissipation ribs arranged in the vertical direction, and two adjacent heat dissipation ribs on the same inner wall form an insertion space for the heat dissipation protrusion to be inserted, and the number of insertion spaces on the same side wall corresponds one-to-one with the heat dissipation protrusion.

[0014] A further preferred embodiment of this utility model is: the heat dissipation rib has a portion protruding from the outside of the barrel body, the heat dissipation rib is provided with a through hole arranged along its length direction, and the portion of the heat dissipation rib located on the outside of the barrel body has an opening arranged along its length direction, the opening communicating with the through hole.

[0015] Compared with the prior art, the present invention has the following advantages; 1. By sequentially assembling series-parallel heat-conducting plate assemblies and a casing from the inside out at the battery pack, a multi-layered, large-contact-area, solid-state heat conduction path is formed from the inside out. When heat is generated from the core heat source (battery cell), it is directly transferred to the casing, which is in contact with the outside environment, through the closely connected series-parallel plates and heat-conducting plate assemblies. This is an active and efficient heat conduction process, avoiding heat accumulation inside and solving the core problem of "difficulty in dissipating internal heat" in the background technology.

[0016] 2. In this solution, the series-parallel connection plate is connected to each battery cell to collect heat at the source; the heat-conducting plate assembly fully covers the series-parallel connection plate, ensuring the uniformity and high efficiency of heat collection; the heat-conducting plate assembly and the casing serve as a large-area heat diffusion and final dissipation carrier, achieving uniform heat distribution and efficient heat dissipation. This "point-surface-volume" heat transfer structure ensures a sufficiently large contact area throughout the entire path of heat generation and dissipation, enabling heat to be quickly, effectively, and uniformly extracted from the concentrated area of ​​the battery cells and transferred to the outside of the entire battery pack, completely solving the problems of uneven heat dissipation and low heat dissipation efficiency in the background technology.

[0017] 3. This heat dissipation structure perfectly integrates electrical connections (series and parallel boards) with heat dissipation function, eliminating the need for complex and space-consuming independent air ducts or external heat dissipation fins, resulting in a more compact structure. Attached Figure Description

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. However, those skilled in the art will understand that these drawings are drawn only for the purpose of explaining the preferred embodiments and therefore should not be regarded as a limitation on the scope of the present invention. In addition, unless otherwise specified, the drawings are only schematic representations of the composition or structure of the described objects and may contain exaggerated displays, and the drawings are not necessarily drawn to scale.

[0019] Figure 1 This is a three-dimensional structural diagram of a preferred embodiment of the present invention; Figure 2 This is a three-dimensional structural diagram of the preferred embodiment of the present invention after disassembling the barrel body; Figure 3 This is a three-dimensional structural diagram of the preferred embodiment of the present invention after disassembling the barrel and the heat-conducting plate; Figure 4 This is a three-dimensional structural diagram of the preferred embodiment of the present invention after disassembling the barrel body, heat-conducting plate, and heat-conducting composite plate. Figure 5 This is an exploded view of a preferred embodiment of the present invention.

[0020] In the diagram: 1. Battery pack; 2. Series-parallel connection board; 21. Interface; 3. Heat-conducting plate assembly; 31. Heat-conducting composite plate; 32. Heat-conducting plate; 321. Heat dissipation protrusion; 4. Barrel body; 41. Heat dissipation fins; 42. Insertion space; 43. Through hole; 44. Opening. Detailed Implementation

[0021] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Those skilled in the art will appreciate that these descriptions are merely descriptive and exemplary and should not be construed as limiting the scope of protection of the present invention.

[0022] It should be noted that similar labels in the following figures indicate similar items; therefore, once an item is defined in one figure, it may not be further defined and explained in subsequent figures.

[0023] This embodiment mainly describes a heat dissipation structure for a lithium-ion battery pack, as detailed below: like Figures 1 to 5 As shown, a heat dissipation structure for a lithium-ion battery pack includes, from the inside out: a battery pack 1, a series-parallel connection plate 2, a heat-conducting plate assembly 3, and a casing 4. The battery pack 1 consists of multiple uniformly distributed cells (not shown in the figure), with each cell serving as the core heat-generating unit. The series-parallel connection plate 2 is located on both sides of the battery pack 1, connecting the electrodes of the cells on the same side and facilitating energy transfer and circuit continuity. While providing electrical connection, the series-parallel connection plate 2 also maintains close contact with the cells, acting as the initial medium for heat transfer. The casing 4 serves as the outermost layer of the battery pack 1 and is tightly fitted to the heat-conducting plate assemblies 3 on both sides of the battery pack. The casing 4 encloses the battery pack 1, the series-parallel connection plate 2, and the heat-conducting plate assembly 3. These components, along with the casing 4, form a heat transfer path from the cells to the external environment, effectively reducing heat accumulation inside the battery pack and improving heat dissipation efficiency and battery safety. In this invention, the barrel 4 not only provides structural support and protection for the battery pack 1, but also undertakes the task of ultimately transferring heat to the external environment. The barrel 4 is in direct contact with the outside world, and its large outer surface area provides ample channels for heat to dissipate into the surrounding environment through natural convection. This battery heat dissipation structure is applicable to both square and cylindrical battery cells.

[0024] Specifically, in this invention, the heat-conducting plate assembly 3 can have multiple implementations. For example, the heat-conducting plate assembly 3 can be a single heat-conducting composite plate 31 or a single heat-conducting plate 32, or the heat-conducting plate assembly 3 can be composed of a heat-conducting composite plate 31 and a heat-conducting plate 32. When the heat-conducting plate assembly 3 is only a single heat-conducting composite plate 31 or a single heat-conducting plate 32, the heat-conducting composite plate 31 or the heat-conducting plate 32 covers and adheres to the outer surface of the two parallel plates 2 and is attached to the inner wall of the barrel 4. In this invention, the heat-conducting plate assembly 3 is preferably composed of a heat-conducting composite plate 31 and a heat-conducting plate 32. The heat-conducting composite plate 31 is sandwiched between the parallel plates 2 and the heat-conducting plate 32, and both sides of the heat-conducting composite plate 31 are tightly attached to the parallel plates 2 and the heat-conducting plate 32, respectively. This design has excellent thermal conductivity, can effectively absorb the heat generated by the battery cell, and conduct the heat away from the parallel plates 2. The positioning design of the heat-conducting composite plate 31 fills the microscopic gap between the series-parallel plates 2 and the heat-conducting plate 32, reducing contact thermal resistance and ensuring a larger contact area, thereby maximizing the efficiency of heat collection. The heat-conducting plate 32, acting as an intermediate layer, further diffuses heat laterally, ensuring uniform heat transfer to the barrel 4 and improving the overall heat dissipation effect.

[0025] This solution forms a multi-level heat transfer path through the thermally conductive composite plate 31, the thermally conductive plate assembly 3, and the casing 4. When the battery pack 1 operates, causing the cells to heat up, heat is generated from the cells, transferred through the series-parallel connection plate 2 to the thermally conductive composite plate 31, then conducted by the thermally conductive composite plate 31 to the thermally conductive plate 32, and finally transferred through the thermally conductive plate 32 to the casing 4, where efficient natural convection cooling occurs between the casing 4 and the outside environment. All components along the entire heat transfer path have a large contact area, ensuring that heat can be effectively collected and dissipated from the inside of the battery pack 1 from the inside out. Heat from the cells no longer accumulates inside, achieving overall temperature balance in the battery pack 1, reducing the internal temperature gradient, significantly delaying capacity decay, reducing the risk of thermal runaway, and greatly improving the overall safety of the battery pack 1.

[0026] The heat inside battery pack 1 can be effectively and quickly dissipated, which can keep the operating temperature of battery pack 1 within a more suitable range, thereby slowing down the aging rate of battery materials, extending the cycle life of the battery, and maintaining the stable performance of the battery during charging and discharging.

[0027] like Figure 3 and Figure 5 As shown, the series-parallel connection board 2 is provided with an interface 21 that matches the battery cell one by one. The series-parallel connection board 2 is connected to the electrode post of the battery cell through the interface 21. The interface 21 serves as both a current path and a heat flow "collection port", so that the heat of a single battery cell is absorbed laterally by the series-parallel connection board 2 at the source and simultaneously discharged, so that the heat on the battery cell can be discharged quickly and evenly, solving the problem of local thermal runaway caused by uneven local heat dissipation.

[0028] Specifically, the series-parallel plate 2 is a metal substrate or ceramic substrate with high thermal conductivity. The metal substrate is generally made of copper, aluminum, or iron, with copper and aluminum substrates being preferred. These two metals have much higher thermal conductivity than stainless steel, which can conduct the instantaneous temperature rise of the electrode post to the thermally conductive composite plate 31 within seconds. At the same time, the material cost is low and it is easy to stamp and form, balancing performance and the economy of mass production. The ceramic substrate is generally made of alumina or aluminum nitride ceramic, which ensures both high thermal conductivity and good electrical insulation properties. This ensures electrical safety while enabling rapid lateral heat dissipation from the cell, reducing thermal resistance and extending battery life.

[0029] Specifically, the heat-conducting plate 32 is a metal plate, graphene heat dissipation plate, ceramic plate, or composite material plate with high thermal conductivity. Metal plates include, but are not limited to, aluminum plates, copper plates, iron plates, aluminum nitride plates, and silicon carbide plates. Ceramic plates include, but are not limited to, aluminum nitride, silicon carbide, and silicon nitride ceramics. The ceramic substrate possesses high thermal conductivity and insulation properties. Composite material plates include, but are not limited to, carbon fiber-aluminum laminates, carbon fiber-copper laminates, and diamond-copper composite material plates, achieving lightweight and high strength. The barrel 4 is a metal barrel with high thermal conductivity or a high-strength, high-thermal-conductivity composite material barrel. Metal barrels include, but are not limited to, aluminum, copper, and iron, with aluminum being preferred. Composite material barrels include, but are not limited to, high-thermal-conductivity epoxy resin-carbon fiber composite materials, carbon fiber / copper laminates, diamond-aluminum composite materials, and graphene-aluminum honeycomb sandwich panels, balancing heat dissipation performance and structural strength to meet the needs of different application scenarios. The heat-conducting composite plate 31 includes thermally conductive silicone sheets, thermally conductive graphite sheets, thermally conductive graphene sheets, and thermally conductive aluminum sheets.

[0030] like Figure 2 and Figure 5 As shown, the heat-conducting plate 32 is provided with at least one outwardly protruding heat dissipation bump 321. The outer end face of the heat dissipation bump 321 is in contact with the inner wall of the barrel 4. The heat dissipation bump 321 increases the contact area between the heat-conducting plate 32 and the barrel 4, and improves the efficiency of heat transfer from the heat-conducting plate 32 to the barrel 4. At the same time, the bump structure also enhances the structural strength of the heat-conducting plate 32 and improves the overall stability.

[0031] Specifically, the heat dissipation bump 321 is set along the length of the heat conduction plate 32, running through the entire length of the heat conduction plate 32 to form a continuous heat transfer channel. It can quickly guide the heat in the axial direction of the cell to both ends of the barrel 4, avoid heat concentration in the middle area of ​​the battery pack 1, and reduce the axial temperature difference. At the same time, the heat dissipation bump 321 can slide along the inner wall of the barrel 4 when the battery pack 1 thermally expands, providing displacement compensation and preventing thermal stress concentration from causing structural damage.

[0032] like Figure 5As shown, the four inner walls of the barrel 4 are provided with heat dissipation ribs 41 arranged in the vertical direction. Two adjacent heat dissipation ribs 41 on the same inner wall form an insertion space 42 for the heat dissipation protrusion 321 to be inserted. The number of insertion spaces 42 on the same side wall corresponds one-to-one with the heat dissipation protrusion 321. The heat dissipation ribs 41 not only serve to position the heat conduction plate 32, but also further increase the heat dissipation area of ​​the barrel 4 and improve the efficiency of heat diffusion to the external environment.

[0033] Specifically, the heat dissipation fin 41 has a portion protruding from the outside of the barrel body 4. The heat dissipation fin 41 has a through hole 43 arranged along its length. The portion of the heat dissipation fin 41 located on the outside of the barrel body 4 has an opening 44 arranged along its length. The opening 44 communicates with the through hole 43. The through hole 43 and the opening 44 form an air convection channel, which enhances the heat exchange capacity between the heat dissipation fin 41 and the external air, further improves the heat dissipation efficiency, and solves the problem of insufficient contact area between the heat sink and the heat source and heat accumulation in traditional heat dissipation structures.

[0034] This solution employs a combination of battery cells, series-parallel interconnected plates 2, thermally conductive composite plates 31, aluminum thermally conductive plates 32, and an aluminum casing 4. The structure is clear and easy to manufacture and assemble. The combination of aluminum and high thermal conductivity silicone offers high cost-effectiveness and mature manufacturing processes, making this technical solution highly feasible in practical applications.

[0035] In the description of this utility model, it should be noted that the terms "upper", "lower", "front", "rear", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the utility model product is usually placed in during use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0036] The above provides a detailed description of a heat dissipation structure for a lithium-ion battery pack. Specific examples have been used to illustrate the principle and implementation of this utility model. The description of the above embodiments is only for the purpose of helping to understand this utility model and its core ideas. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the principle of this utility model, and these improvements and modifications also fall within the protection scope of the claims of this utility model.

Claims

1. A heat dissipation structure for a lithium-ion battery pack, characterized in that, From the inside out, the following are included: A battery pack consists of multiple evenly distributed battery cells; The series-parallel connection plate is located on both sides of the battery pack and is used to connect the electrodes of the cells on the same side and transfer heat. The heat-conducting plate assembly covers the surface of the two parallel plates away from the battery pack and absorbs heat from the parallel plates and the battery cells. The barrel body fits tightly against the heat-conducting plate assemblies on both sides of the battery pack, and houses the battery pack, series and parallel plates, and heat-conducting plate assemblies inside. The series-parallel plates, heat-conducting plate assembly, and barrel body constitute the heat transfer path from the battery cell to the external environment.

2. The heat dissipation structure for a lithium-ion battery pack according to claim 1, characterized in that: The heat-conducting plate assembly includes a heat-conducting composite plate and a heat-conducting plate. The heat-conducting composite plate is sandwiched between the series-parallel plate and the heat-conducting plate, and both sides of the heat-conducting composite plate are tightly attached to the series-parallel plate and the heat-conducting plate, respectively.

3. The heat dissipation structure for a lithium-ion battery pack according to claim 1, characterized in that: The heat-conducting plate assembly is a single heat-conducting composite plate or a single heat-conducting plate. The heat-conducting composite plate or heat-conducting plate covers and adheres to the outer surface of two parallel plates and is attached to the inner wall of the barrel.

4. A heat dissipation structure for a lithium-ion battery pack according to claim 1 or 2, characterized in that, The heat-conducting plate is a metal plate, graphene heat dissipation plate, ceramic plate or composite material plate with high thermal conductivity, and the barrel body is a metal barrel with high thermal conductivity or a high-strength composite material barrel body with high thermal conductivity.

5. A heat dissipation structure for a lithium-ion battery pack according to claim 1, characterized in that, The series-parallel connection board is provided with an interface that mates with each battery cell, and the series-parallel connection board is connected to the battery cells through the interface.

6. The heat dissipation structure for a lithium-ion battery pack according to claim 1, characterized in that, The series and parallel plates are made of metal or ceramic substrates with high thermal conductivity.

7. A heat dissipation structure for a lithium-ion battery pack according to claim 2, characterized in that, The heat-conducting plate has at least one outwardly protruding heat dissipation bump on the side away from the battery pack, and the outer end face of the heat dissipation bump is in contact with the inner wall of the barrel.

8. A heat dissipation structure for a lithium-ion battery pack according to claim 7, characterized in that, The heat dissipation bumps are arranged along the length of the heat-conducting plate.

9. A heat dissipation structure for a lithium-ion battery pack according to claim 7, characterized in that, The barrel body has heat dissipation ribs arranged vertically on all four inner walls. Two adjacent heat dissipation ribs on the same inner wall form an insertion space for heat dissipation protrusions to be inserted. The number of insertion spaces on the same side wall corresponds one-to-one with the number of heat dissipation protrusions.

10. A heat dissipation structure for a lithium-ion battery pack according to claim 9, characterized in that, The heat dissipation rib has a portion protruding from the outside of the barrel body, and the heat dissipation rib has a through hole arranged along its length. The portion of the heat dissipation rib located on the outside of the barrel body has an opening arranged along its length, and the opening communicates with the through hole.

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