A battery pack structure

Abstract

This invention discloses a battery pack structure, relating to the field of battery pack heat dissipation technology. It includes a lower temperature equalization unit and an upper dual-mode heat dissipation unit. The lower temperature equalization unit includes a housing containing battery cells filled with an insulating and thermally conductive immersion liquid, ensuring complete immersion of the cells for uniform temperature distribution. The upper dual-mode heat dissipation unit includes a dual-cavity heat dissipation aluminum cover sealed to the top of the housing. Its lower side is attached to the battery cell terminals and aluminum foil via an insulating and thermally conductive elastic pad, dissipating the most concentrated heat from the top via the shortest path. The dual-cavity heat dissipation aluminum cover integrates a liquid cooling channel and an air cooling channel located above it. This invention, through a thermodynamically optimized design of "bottom full immersion temperature equalization + top directional heat conduction," completely eliminates the temperature difference between the top and bottom of the battery cells. Combined with dual-mode switching of air cooling priority and liquid cooling backup, it significantly improves heat dissipation efficiency, battery cell temperature uniformity, safety, cycle life, and reduces energy consumption.

Description

Technical Field

[0001] This invention relates to the field of battery pack heat dissipation technology, specifically to a battery pack structure. Background Technology

[0002] As a core energy storage component, battery packs have been widely used in fields such as home energy storage, rail transportation, electric locomotives, and marine power. Due to the complexity of application scenarios and the high risks of operation in electrical and confined spaces, the market has placed extremely high demands on their safety (such as preventing thermal runaway), reliability (long cycle life), and environmental adaptability (waterproof, shockproof, and resistant to high and low temperatures).

[0003] Currently, most battery pack thermal management technologies employ bottom liquid cooling structures for heat dissipation. For example, Chinese invention patent CN120834334A discloses an immersion liquid-cooled energy storage PACK box, which significantly improves overall heat dissipation efficiency through a composite cooling design combining static immersion liquid and bottom liquid cooling plate. Another example is Chinese invention patent CN121584084A, which discloses a high-rate immersion pack box structure that uses a circulating flow channel in conjunction with the flow channel inside the bottom plate to remove heat from the cells within the immersion liquid, reducing the temperature difference of the cells during operation under four-sided heat dissipation conditions.

[0004] However, the above-mentioned technical solutions have the following drawbacks: During the charging and discharging process, the internal electrochemical reactions of the battery generate heat, especially at the top of the cell. When using a bottom liquid cooling solution, the bottom, which has lower heat, dissipates heat faster, while the top, which has more heat, dissipates heat more slowly (untimely heat dissipation). This can easily lead to heat accumulation at the top of the cell, forming a significant "top-high, bottom-low" temperature difference, affecting the battery pack's lifespan and potentially causing thermal runaway due to localized overheating. Furthermore, in the field of marine battery packs, although high-temperature conditions exist in the marine environment, they account for a relatively small proportion of the year's operating conditions. For most of the time (such as sailing in temperate or cold-climate waters or anchoring at night), the ambient temperature of the battery pack is moderate or low. Under such conditions, if an active liquid cooling system is still activated for cooling, energy consumption will increase. Summary of the Invention

[0005] To address these issues, embodiments of the present invention provide a battery pack structure to solve the problems of poor heat dissipation effect, untimely heat dissipation at the top of the battery cell, poor temperature uniformity of the battery cell, high risk of thermal runaway, and high energy loss in existing bottom liquid cooling heat dissipation structures.

[0006] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0007] A battery pack structure includes a lower heat dissipation unit and an upper dual-mode heat dissipation unit;

[0008] The lower temperature equalization unit includes a box, the top of which is open, and the box contains battery cells and is filled with insulating and thermally conductive immersion liquid. The battery cells are immersed in the insulating and thermally conductive immersion liquid.

[0009] The upper dual-mode heat dissipation unit includes a dual-cavity heat dissipation aluminum cover, which is sealed and installed on the top opening of the housing. Part of the lower side of the dual-cavity heat dissipation aluminum cover is attached to the terminal post of the battery cell and the aluminum bar connecting the battery cell through an insulating thermally conductive elastic pad. The dual-cavity heat dissipation aluminum cover is provided with a liquid cooling channel and an air cooling channel above the liquid cooling channel. The liquid cooling channel is continuously and uniformly distributed in the dual-cavity heat dissipation aluminum cover. The two ends of the liquid cooling channel are respectively provided with a liquid inlet and a liquid outlet. The air cooling channel is provided with multiple uniformly distributed heat dissipation fins, which extend along the extension direction of the air cooling channel. The two ends of the air cooling channel are respectively provided with an air inlet and an air outlet.

[0010] Furthermore, the liquid cooling channel is S-shaped; the liquid inlet and liquid outlet are located on the front end face of the dual-cavity heat dissipation aluminum cover, and are distributed on the left and right sides respectively.

[0011] Furthermore, the air-cooling channel is arranged in the front-to-back direction, the air inlet is located on the rear end face of the dual-cavity heat dissipation aluminum cover, and the air outlet is located on the front end face of the dual-cavity heat dissipation aluminum cover; an axial flow fan is installed outside the housing, and the air inlet of the axial flow fan is connected to the air outlet of the air-cooling channel.

[0012] Furthermore, multiple air-cooled channels and axial flow fans are provided, and the multiple axial flow fans are connected to the multiple air-cooled channels in a one-to-one correspondence.

[0013] Furthermore, the air outlet of the air-cooled flow channel is connected to a transfer air duct, and the air inlet of the axial flow fan is connected to the other end of the transfer air duct.

[0014] Furthermore, the insulating and thermally conductive immersion liquid is a hydrocarbon-based immersion liquid, and the insulating and thermally conductive elastic pad is a modified nitrile rubber pad, a thermally conductive silicone pad, or a thermally conductive acrylate pad.

[0015] Furthermore, the dual-cavity heat dissipation aluminum cover includes an aluminum cavity plate and an aluminum cover plate. The liquid cooling channel is disposed inside the aluminum cavity plate and near the lower side. The heat dissipation fins are disposed on the upper surface of the aluminum cavity plate. The aluminum cover plate is upside down and installed on the aluminum cavity plate and sealed to the aluminum cavity plate to form the air cooling channel.

[0016] Furthermore, an oil viewing mirror is provided on one side of the box near the opening.

[0017] Furthermore, the periphery of the enclosure is provided with a stacked structure with load-bearing beams, and the enclosure, the double-cavity heat dissipation aluminum cover, and the stacked structure are provided with an anti-corrosion layer.

[0018] Furthermore, a data acquisition unit is installed outside the enclosure, and a pin connecting the inside and outside is welded to the enclosure. After the data cable of the data acquisition unit is stripped, it passes through the pin and enters the enclosure and connects to the battery cell. Sealant is injected into the gap between the pin and the stripped data cable.

[0019] The battery pack structure provided by this invention, through the collaborative design of a "lower-layer heat dissipation unit" and an "upper-layer dual-mode heat dissipation unit," constructs a novel immersion-type top heat dissipation structure. Compared to the existing technology that uses bottom liquid cooling, leading to heat accumulation at the top of the battery cell and creating a "top-high, bottom-low" temperature difference, this invention has the following advantages:

[0020] 1. Significantly improves cell temperature uniformity and extends service life.

[0021] By completely immersing the battery cell in an insulating and thermally conductive immersion liquid, the excellent thermal conductivity and fluidity of this liquid medium enable uniform heating and cooling of the entire battery cell, effectively avoiding the problem of excessive temperature difference between the top and bottom of the cell in traditional bottom liquid cooling solutions. Simultaneously, combined with an upper dual-mode heat dissipation unit, targeted heat conduction is applied to the battery cell's terminals and aluminum core (i.e., the areas with the highest heat concentration), dissipating heat through the shortest path. This fundamentally solves the problem of insufficient heat dissipation at the top of the battery cell, ensuring a uniform temperature distribution within the cell and thus extending the overall cycle life of the battery pack.

[0022] 2. Achieve efficient dual-mode heat dissipation and reduce system energy consumption.

[0023] Based on the principle of full immersion and temperature equalization of the battery cells, the upper dual-cavity heat dissipation aluminum cover integrates both liquid cooling and air cooling modes. It can flexibly switch according to the ambient temperature. In normal temperature or low temperature environments (such as when ships are sailing in temperate or cold waters or anchoring at night), the air cooling mode can be used alone without having to turn on the energy-intensive liquid cooling system, thereby effectively reducing the energy loss of the entire battery pack and improving energy utilization efficiency. In the field of marine battery packs, this is a perfect fit for the actual operating characteristics of the marine environment, where high-temperature conditions account for a small proportion.

[0024] 3. Significantly improves safety performance and reduces the risk of thermal runaway.

[0025] The lower compartment is filled with an insulating and thermally conductive immersion fluid. This fluid not only serves to even out temperature and dissipate heat, but also effectively isolates oxygen. Even if a single cell experiences thermal runaway, the large amount of immersion fluid provides excellent barrier and heat absorption, greatly suppressing the spread of thermal runaway between cells. This fundamentally reduces the probability of thermal runaway of the entire battery pack and significantly improves the safety of the battery pack under complex operating conditions. Attached Figure Description

[0026] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0027] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0028] Figure 1 This is a schematic diagram of a battery pack structure provided in an embodiment of the present invention;

[0029] Figure 2 for Figure 1 A schematic diagram of the structure shown after removing the decorative layer;

[0030] Figure 3 for Figure 2 A schematic diagram of the structure from another viewpoint;

[0031] Figure 4 for Figure 3 A schematic diagram of the structure shown (viewed from front to back);

[0032] Figure 5 for Figure 3 A cross-sectional view of the structure shown (viewed from the back after being cut along the left and right directions);

[0033] Figure 6 for Figure 5 Enlarged view of A in the middle;

[0034] Figure 7 for Figure 3 A schematic diagram of the structure shown after removing the aluminum cover plate;

[0035] Figure 8 for Figure 7 Enlarged view of B in the middle;

[0036] Figure 9 for Figure 7 A cross-sectional view of the structure shown (viewed from the back after being cut along the left and right directions);

[0037] Figure 10 for Figure 9 A magnified view of C.

[0038] In the diagram: 1. Housing; 2. Battery cell; 3. Insulating and thermally conductive immersion liquid; 4. Dual-cavity heat dissipation aluminum cover; 5. Terminal post; 6. Insulating and thermally conductive elastic pad; 7. Liquid cooling channel; 8. Air cooling channel; 9. Liquid inlet; 10. Liquid outlet; 11. Heat dissipation fins; 12. Air inlet; 13. Axial flow fan; 14. Adapter air duct; 15. Oil level indicator; 16. Load-bearing beam; 17. Decorative layer; 18. Aluminum profile cavity plate; 19. Aluminum cover plate; 20. Honeycomb vents. Detailed Implementation

[0039] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] like Figure 1-10 As shown, this embodiment provides a battery pack structure, including a lower heat dissipation unit and an upper dual-mode heat dissipation unit.

[0041] The lower temperature equalization unit includes a box 1 with an open top. Inside the box 1, there are battery cells 2 and a full insulating and thermally conductive immersion liquid 3. The battery cells 2 are immersed in the insulating and thermally conductive immersion liquid 3.

[0042] The upper dual-mode heat dissipation unit includes a dual-cavity heat dissipation aluminum cover 4. The dual-cavity heat dissipation aluminum cover 4 is sealed and installed on the top opening of the housing 1. Part of the lower side of the dual-cavity heat dissipation aluminum cover 4 is attached to the terminal post 5 of the battery cell 2 and the aluminum bar connecting the battery cell 2 through an insulating thermally conductive elastic pad 6. The dual-cavity heat dissipation aluminum cover 4 is provided with a liquid cooling channel 7 and an air cooling channel 8 located above the liquid cooling channel 7. The liquid cooling channel 7 is continuously and uniformly distributed in the dual-cavity heat dissipation aluminum cover 4, and liquid inlet 9 and liquid outlet 10 are respectively provided at both ends of the liquid cooling channel 7. The air cooling channel 8 is provided with a plurality of uniformly distributed heat dissipation fins 11, which extend along the extension direction of the air cooling channel 8, and air inlet 12 and air outlet are respectively provided at both ends of the air cooling channel 8; for example, the air inlet 12 is composed of a honeycomb-shaped distribution of numerous small holes.

[0043] By adopting the above technical solution, at least the following advantages are achieved:

[0044] 1. The thermodynamically optimized design of "non-flowing immersion" and "top-directed heat conduction" reduces heat accumulation at the top, achieving rapid heat dissipation and high heat dissipation efficiency. The battery cell 2 is fully immersed in an insulating thermally conductive liquid, but the immersion liquid does not flow within the housing 1 (meaning it is not driven by external power). The heat exchange capacity between the battery cell 2 and its surroundings is enhanced by the flow effect formed by natural convection. Simultaneously, combined with the top heat dissipation structure, the heat from the electrode post 5 area, where the heat generation of the battery cell 2 is most concentrated and severe, is directly conducted away via the shortest path. This design fully conforms to the thermodynamic principle of "heat rise," causing heat to spontaneously accumulate at the top and be rapidly carried away, resulting in heat dissipation efficiency far superior to traditional bottom liquid cooling solutions.

[0045] 2. Fundamentally eliminates the temperature difference between the top and bottom of cell 2, achieving ultimate temperature uniformity. Through the full-encapsulation characteristics of the immersion liquid, cell 2 is in a uniform temperature field, completely solving the persistent problem of "cold bottom and hot top" temperature difference in existing technologies. This ensures that cell 2 is always in the optimal operating temperature range, significantly improving the safety and cycle life of cell 2.

[0046] 3. Achieve efficient dual-mode heat dissipation and reduce system energy consumption. Based on the full immersion and temperature uniformity of cell 2, the upper dual-cavity heat dissipation aluminum cover 4 integrates both liquid cooling and air cooling modes. It can flexibly switch according to the ambient temperature. In normal or low-temperature environments (such as when ships are sailing in temperate or cold waters or anchoring at night), the air cooling mode can be activated independently, eliminating the need to turn on the energy-intensive liquid cooling system. This effectively reduces the energy loss of the entire battery pack and improves energy utilization efficiency. Under normal conditions (at normal temperature), the temperature of the top heat dissipation fins 11 is reduced directly by the axial flow fan 13. When the ambient temperature exceeds a certain level (e.g., 35℃), the axial flow fan 13 is turned off, and the external cooling cycle is activated to cool cell 2 through liquid cooling. Ultimately, the temperature of cell 2 is kept within the optimal operating temperature range (e.g., 25℃-35℃), ensuring the safety and cycle life of cell 2.

[0047] 4. A multi-layered safety protection system is constructed, approaching "zero risk" of thermal runaway. The immersion fluid not only conducts heat but also forms a physical isolation barrier around cell 2, effectively isolating oxygen. In the event of thermal runaway in a single cell 2, the large amount of immersion fluid can quickly absorb heat and interrupt the chain reaction, minimizing the probability of thermal runaway spreading. Combined with C5-level anti-corrosion coating and IP68 protection rating, the battery pack can still operate reliably for a long time in the harsh environment of high salt spray and high humidity in the ocean.

[0048] 5. By attaching a compressible insulating and thermally conductive elastic pad 6 to the large surface of the aluminum bar, it can adapt to minor unevenness under the action of bolt tightening, ensuring tight contact between the pole 5 and the heat sink cover, while ensuring high voltage insulation, thus overcoming the key technical bottleneck of insulation in the top heat dissipation structure.

[0049] In an optional embodiment, the liquid cooling channel 7 is S-shaped; the liquid inlet 9 and the liquid outlet 10 are located on the front end face of the dual-cavity heat dissipation aluminum cover 4 and are distributed on the left and right sides respectively.

[0050] By adopting the above technical solution, at least the following advantages are achieved: By setting the liquid cooling channel 7 to an S-shape and ensuring its continuous and uniform distribution within the dual-cavity heat dissipation aluminum cover 4, the flow path and residence time of the coolant per unit area are significantly extended, increasing the heat exchange area and thus improving the heat exchange efficiency and temperature uniformity in liquid cooling mode. The inlet 9 and outlet 10 are positioned on the front face, one on the left and one on the right, resulting in a compact layout that facilitates centralized connection and maintenance of external piping.

[0051] In an optional embodiment, the air-cooled flow channel 8 is arranged in a front-to-back direction, the air inlet 12 is located on the rear end face of the dual-cavity heat dissipation aluminum cover 4, and the air outlet is located on the front end face of the dual-cavity heat dissipation aluminum cover 4; multiple air-cooled flow channels 8 and axial flow fans 13 are respectively provided, and multiple axial flow fans 13 are connected to multiple air-cooled flow channels 8 in a one-to-one correspondence; the air outlet of the air-cooled flow channel 8 is connected to a transfer air duct 14, and the air inlet of the axial flow fan 13 is connected to the other end of the transfer air duct 14. Exemplarily, two air-cooled flow channels 8, two transfer air ducts 14, and two axial flow fans 13 are respectively provided; wherein, there is no substantial dividing structure in the middle of the two air-cooled flow channels 8 (that is: nominally there are two to correspond to two axial flow fans 13; in fact, it is a whole air-cooled flow channel 8, which is divided into many small channels by numerous heat dissipation fins 11 arranged inside it. The front and rear ends of the small channels are connected, so that they can share a single air inlet 12 for air intake and can use two air outlets for air exhaust). For example, the transition duct 14 is essentially a tubular structure that connects the air outlet of the air-cooled flow channel 8 and the air inlet of the axial flow fan 13.

[0052] By adopting the above technical solution, at least the following advantages are achieved: the air-cooled flow channel 8 is arranged along the front-to-back direction and connected to the axial flow fan 13 at the air outlet, forming a highly efficient through-flow air duct structure that can quickly draw away heat from the heat dissipation fins 11, ensuring the heat dissipation efficiency of the air-cooling mode. Multiple axial flow fans 13 correspond one-to-one with the air-cooled flow channel 8, allowing for zoned heat dissipation control based on the actual heat generation in different areas of the battery cell 2, further improving heat dissipation accuracy and energy efficiency ratio. The connection via the adapter air duct 14 overcomes the limitations of installation space, making the fan layout more flexible.

[0053] In this embodiment, the insulating and thermally conductive immersion liquid 3 is a hydrocarbon-based immersion liquid, and the insulating and thermally conductive elastic pad 6 is a modified nitrile rubber pad, a thermally conductive silicone pad, or a thermally conductive acrylate pad.

[0054] The insulating and thermally conductive immersion fluid 3 is made of hydrocarbons. The selected hydrocarbon-based immersion fluid has been verified in practice for nearly two years and has good compatibility with materials such as housing 1 and seals. It effectively solves the core problems of material corrosion and swelling that are common in immersion technology, and lays a solid foundation for achieving the goal of "zero risk of thermal runaway".

[0055] Nitrile rubber possesses excellent elasticity, oil resistance, abrasion resistance, and sealing properties, and naturally exhibits good electrical insulation. However, its thermal conductivity is poor. By modifying it with fillers such as alumina, boron nitride, silicon carbide, and graphene microflakes, it can simultaneously possess insulation, thermal conductivity, and elasticity. Thermally conductive silicone gaskets use addition-type / condensation-type silicone rubber as their base material, and their thermal conductivity mechanism is achieved through highly filled alumina, boron nitride, zinc oxide, or ceramic composite fillers. Thermally conductive acrylate gaskets use acrylic copolymers as their base material, characterized by: superior balanced oil resistance compared to silicone, superior thermal conductivity compared to NBR, low compressive stress, and strong initial tack.

[0056] By adopting the above technical solution, at least the following advantages are achieved: The use of a hydrocarbon-based immersion liquid provides excellent insulation and chemical stability, ensuring long-term safe contact with the battery cell 2 and guaranteeing insulation performance. The selection of modified nitrile rubber, thermally conductive silicone, or thermally conductive acrylate gaskets as the insulating and thermally conductive elastic pad 6 ensures good thermal contact between the electrode post 5 and the heat sink cover, while also providing crucial electrical insulation, effectively solving the dual technical challenges of "thermal conduction" and "insulation" faced by the top heat dissipation structure.

[0057] In an optional embodiment, the dual-cavity heat dissipation aluminum cover 4 includes an aluminum cavity plate 18 and an aluminum cover plate 19. The liquid cooling channel 7 is disposed inside the aluminum cavity plate 18 and near the lower side. The heat dissipation fins 11 are disposed on the upper surface of the aluminum cavity plate 18. The aluminum cover plate 19 is upside down and installed on the aluminum cavity plate 18 and is sealed to the aluminum cavity plate 18 to form an air cooling channel 8.

[0058] By adopting the above technical solution, at least the following advantages are achieved: The split structure of the dual-cavity heat dissipation aluminum cover 4 into an aluminum cavity plate 18 and an aluminum cover plate 19 greatly simplifies the processing technology for complex internal flow channels and fin structures, reducing manufacturing difficulty and cost. The aluminum cavity plate 18 can be formed using an extrusion process, ensuring the precision and consistency of the liquid cooling flow channel 7 and the heat dissipation fins 11; the aluminum cover plate 19 can be completed through simple stamping or machining, facilitating subsequent sealing and assembly.

[0059] In an optional embodiment, an oil viewing mirror 15 is provided on one side of the housing 1 near the opening.

[0060] By adopting the above technical solution, at least the following advantages are achieved: An oil observation mirror 15 is installed on the side wall of the box 1, so that maintenance personnel can directly and in real time observe the liquid level and status (such as whether it changes color or becomes turbid) of the insulating and thermally conductive immersion liquid 3 inside the box 1 without disassembling the box 1, which facilitates timely replenishment or replacement and greatly improves the convenience of daily operation and maintenance.

[0061] In an optional embodiment, the periphery of the housing 1 is provided with a stacked structure having load-bearing beams 16. The housing 1, the double-cavity heat dissipation aluminum cover 4, and the stacked structure are all covered with an anti-corrosion layer. A decorative layer 17 (or protective decorative layer 17) is provided outside the housing 1 and the stacked structure, with the decorative layer 17 located outside the anti-corrosion layer. Exemplarily, the decorative layer 17 has honeycomb-shaped vents 20 at the position corresponding to the air outlet of the axial flow fan 13 to facilitate gas exhaust; a window (not shown) is provided at the position corresponding to the oil sight glass 15 on the decorative layer 17 for observation; the air inlet 12 of the air-cooled flow channel 8 must not be covered by the decorative layer 17 but must be exposed to ensure air intake; the double-cavity heat dissipation aluminum cover 4 is coated with an anti-corrosion layer but not with the decorative layer 17 to avoid affecting heat dissipation; the decorative layer 17 is a foam structure or a buffer structure layer, and information such as markings can be sprayed on its outer side.

[0062] By adopting the above technical solution, at least the following advantages are achieved: By providing a stacking structure with load-bearing beams 16 around the perimeter of the housing 1, multiple packs of the present invention can be stably and safely stacked in multiple layers, enabling flexible configuration with a smaller footprint and higher energy output within a limited space, meeting the differentiated power requirements of equipment. The external anti-corrosion layer and decorative layer 17 allow the entire battery pack to withstand the harsh environment of high salt spray and high humidity in the ocean for extended periods, ensuring product reliability and durability. The housing 1 employs sheet metal welding technology, eliminating the need for mold investment, making it particularly suitable for small-batch, multi-variety customized needs, and offering comprehensive advantages such as high strength, short development cycle, and good economic efficiency.

[0063] In an optional embodiment, a data acquisition unit is installed on the outside of the housing 1. The housing 1 is welded with a pin that connects the inside and outside. After the data cable of the data acquisition unit is stripped, it passes through the pin and enters the housing 1 and is connected to the battery cell 2. Sealant is injected into the gap between the pin and the stripped data cable.

[0064] By adopting the above technical solution, at least the following advantages are achieved: The use of metal pins combined with internal potting sealant fundamentally solves the "oil seepage" risk caused by material compatibility issues in traditional cables—that is, the slow leakage of insulation immersion liquid along the gap between the cable sheath and the conductor. This solution ensures long-term reliable sealing at the connection between the data acquisition unit and the battery cell 2 inside the enclosure 1, guaranteeing the integrity of the IP68 protection rating. It also ensures the safe and stable operation of critical electrical components such as the BMS (Battery Management System) externally, avoiding damage to electrical components due to contact with immersion liquid.

[0065] This invention organically combines multiple technical features, including full immersion temperature uniformity of cell 2, targeted top heat conduction, dual-mode intelligent switching heat dissipation, highly compatible sealing materials, convenient stacking structure, and reliable anti-oil creep wiring, to form a complete, efficient, safe, and highly adaptable battery pack thermal management and structural solution. This solution not only solves the core problems of large temperature differences in cell 2, untimely heat dissipation, high risk of thermal runaway, and high energy consumption in existing technologies, but also takes into account the practical application requirements of high corrosion resistance, easy maintenance, high energy density (achieved through stacking), and high reliability in marine environments. Its sheet metal welding housing 1 and split aluminum cover processes ensure performance while also considering economy and flexibility, enabling this high-rate heat dissipation solution to be effectively applied in scenarios with extremely high safety requirements, demonstrating significant technological advancement and broad practical prospects.

[0066] This invention, through the organic combination of the aforementioned technical features, successfully increases the discharge rate of high-capacity large-cell batteries (such as 314AH) from 0.5P to 1P, achieving a 100% rate increase. This enables the successful realization of high-discharge-rate applications that were previously limited by heat dissipation capabilities. Simultaneously, this solution balances economy (sheet metal welding, no mold required), reliability (two years of verification, material compatibility), safety (near-zero risk), and scalability (future support for even higher-rate cells), providing a comprehensive and high-performance pack system solution for marine electrification and energy storage applications.

[0067] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A battery pack structure, characterized in that, Includes a lower-level heat dissipation unit and an upper-level dual-mode heat dissipation unit; The lower temperature equalization unit includes a box (1), the top of the box (1) is open, the box (1) is equipped with a battery cell (2) and filled with insulating and thermally conductive immersion liquid (3), and the battery cell (2) is immersed in the insulating and thermally conductive immersion liquid (3); The upper dual-mode heat dissipation unit includes a dual-cavity heat dissipation aluminum cover (4), which is sealed and installed on the top opening of the housing (1). Part of the lower side of the dual-cavity heat dissipation aluminum cover (4) is attached to the terminal post (5) of the battery cell (2) and the aluminum bar connecting the battery cell (2) through an insulating thermally conductive elastic pad (6). The dual-cavity heat dissipation aluminum cover (4) is provided with a liquid cooling channel (7) and an air cooling channel above the liquid cooling channel (7). The liquid cooling channel (7) is continuously and uniformly distributed within the dual-cavity heat dissipation aluminum cover (4). The liquid cooling channel (7) has an inlet (9) and an outlet (10) at both ends. The air cooling channel (8) has multiple uniformly distributed heat dissipation fins (11) that extend along the extension direction of the air cooling channel (8). The air cooling channel (8) has an air inlet (12) and an air outlet at both ends.

2. The battery pack structure as described in claim 1, characterized in that, The liquid cooling channel (7) is S-shaped; the liquid inlet (9) and liquid outlet (10) are located on the front end face of the dual-cavity heat dissipation aluminum cover (4) and are distributed on the left and right respectively.

3. The battery pack structure as described in claim 1, characterized in that, The air-cooled flow channel (8) is arranged in the front-to-back direction. The air inlet (12) is located on the rear end face of the double-cavity heat dissipation aluminum cover (4), and the air outlet is located on the front end face of the double-cavity heat dissipation aluminum cover (4). An axial flow fan (13) is installed outside the housing (1), and the air inlet of the axial flow fan (13) is connected to the air outlet of the air-cooled flow channel (8).

4. The battery pack structure as described in claim 3, characterized in that, Multiple air-cooled flow channels (8) and axial flow fans (13) are provided respectively, and the multiple axial flow fans (13) are connected to the multiple air-cooled flow channels (8) in a one-to-one correspondence.

5. The battery pack structure as described in claim 3, characterized in that, The air outlet of the air-cooled flow channel (8) is connected to a transfer air duct (14), and the air inlet of the axial flow fan (13) is connected to the other end of the transfer air duct (14).

6. The battery pack structure as described in claim 1, characterized in that, The insulating and thermally conductive immersion liquid (3) is a hydrocarbon-based immersion liquid, and the insulating and thermally conductive elastic pad (6) is a modified nitrile rubber pad, a thermally conductive silicone pad, or a thermally conductive acrylate pad.

7. The battery pack structure as described in claim 1, characterized in that, The dual-cavity heat dissipation aluminum cover (4) includes an aluminum cavity plate (18) and an aluminum cover plate (19). The liquid cooling channel (7) is located inside the aluminum cavity plate (18) and near the lower side. The heat dissipation fins (11) are located on the upper surface of the aluminum cavity plate (18). The aluminum cover plate (19) is upside down installed on the aluminum cavity plate (18) and sealed to the aluminum cavity plate (18) to form the air cooling channel (8).

8. The battery pack structure as described in claim 1, characterized in that, An oil viewing mirror (15) is provided on one side of the box (1) near the opening.

9. The battery pack structure as described in claim 1, characterized in that, The box (1) is provided with a stacked structure with load-bearing beams (16) on its periphery. The box (1), the double-cavity heat dissipation aluminum cover (4) and the stacked structure are provided with an anti-corrosion layer.

10. The battery pack structure as described in claim 1, characterized in that, A data acquisition unit is installed outside the housing (1). A pin connecting the inside and outside is welded to the housing (1). After the data cable of the data acquisition unit is stripped, it is inserted into the housing (1) through the pin and connected to the battery cell (2). Sealant is injected into the gap between the pin and the stripped data cable.

Images