An immersion liquid-cooled battery pack

Abstract

The utility model belongs to battery technical field, concretely relates to a kind of immersion liquid cooling battery pack.The battery pack includes box, box upper end is provided with upper cover, and box interior is provided with several battery modules, and box interior is filled with coolant;The box is provided with cooling pipeline, and the cooling pipeline is immersed in coolant, and the cooling pipeline includes primary liquid inlet pipeline and primary liquid outlet pipeline, and at least three cooling units are arranged in parallel between primary liquid inlet pipeline and primary liquid outlet pipeline, and the two ends of each cooling unit are respectively connected with primary liquid inlet pipeline and primary liquid outlet pipeline.The cooling unit is at least composed of one or more cooling subunits in parallel, and the cooling subunit is sequentially connected by secondary liquid inlet pipeline, circulating sub-pipeline and secondary liquid outlet pipeline.The immersion liquid cooling mode is combined with shunt cooling pipeline design, the efficient uniform cooling of battery module is realized, and the safety and reliability of heat dissipation efficiency and battery system operation are improved.

Description

Technical Field

[0001] This utility model belongs to the field of battery technology, specifically relating to an immersion liquid-cooled battery pack. Background Technology

[0002] As new energy vehicles and energy storage systems develop towards higher energy density and faster charging and discharging, battery thermal management has become a core technology determining system safety, cycle life, and energy efficiency. Battery performance and lifespan are highly dependent on temperature management; the ideal operating temperature needs to be controlled between 25℃ and 45℃. Temperatures that are too high or too low can lead to problems such as capacity decay, thermal runaway, and even explosion.

[0003] Currently, the mainstream cooling method for energy storage battery packs is mostly a cold plate liquid cooling system. This system conducts heat indirectly through contact between the cooling plate and the individual battery cells. While this improves heat dissipation efficiency, it suffers from several drawbacks: reduced heat transfer efficiency due to contact thermal resistance (changes in contact pressure, aging of interface materials); temperature gradients caused by multiple heat conduction paths (temperature differences between cells can reach 8-15℃); the contradiction between the complexity of flow channel design and the energy density of the battery pack; and safety risks caused by coolant leakage. To address these issues, immersion liquid cooling technology has emerged in the field of battery cooling technology. This method directly immerses the battery cells in an insulating cooling medium, completely isolating them from oxygen and achieving efficient heat exchange across the entire surface.

[0004] However, existing immersion liquid cooling technology still has significant drawbacks: without a flow pump, the natural convection heat transfer coefficient of the medium is low during static immersion; and the circulation pipeline with a flow pump is usually only an S-shaped pipeline, which leads to low uniformity of the temperature field inside the battery pack during the heat exchange process. Utility Model Content

[0005] This utility model addresses the problems in the prior art by providing an immersion liquid-cooled battery pack. It solves the problem of low heat transfer coefficient due to natural convection of the medium when statically immersed without a flow pump, and also solves the problem of low uniformity of the temperature field inside the battery pack caused by the fact that the circulation pipeline with a flow pump usually only has an S-shaped pipeline.

[0006] The technical solution adopted in this utility model is as follows: This application provides an immersion liquid-cooled battery pack, including a housing with a top cover. Several battery modules are arranged inside the housing, which is filled with coolant. Cooling pipes are arranged on the housing and immersed in the coolant. The cooling pipes are used to fill and circulate refrigerant. The inlet and outlet of the cooling pipes both pass through the housing and are fixedly connected to it. The cooling pipes include a primary inlet pipe and a primary outlet pipe. At least three cooling units are arranged in parallel between the primary inlet pipe and the primary outlet pipe. The two ends of the cooling units are respectively connected to the primary inlet pipe and the primary outlet pipe.

[0007] Furthermore, the cooling unit consists of at least one cooling subunit or several cooling subunits connected in parallel.

[0008] Furthermore, the cooling subunit consists of a two-stage liquid inlet pipe, a circulation pipe, and a two-stage liquid outlet pipe connected end to end in an S-shaped pipeline.

[0009] Furthermore, the circulation pipe is composed of at least one circulation sub-pipe connected in parallel, with its two ends connected to the secondary inlet pipe and the secondary outlet pipe, respectively.

[0010] Furthermore, at least one auxiliary pipe is connected in parallel to the primary outlet pipe, with both ends of the auxiliary pipe connected to the primary outlet pipe.

[0011] Furthermore, the number of battery modules is at least two, and each battery module is connected in series sequentially.

[0012] Furthermore, the battery module contains several cells arranged side by side, with adhesive strips between adjacent cells.

[0013] Furthermore, the battery module also includes end plates and steel strips at both ends, with the steel strips being wrapped around the two end plates and several battery cells for binding and fixing.

[0014] Furthermore, the projection of the cooling pipes onto the plane where the battery module is located can coincide with the projection of all the battery modules installed inside the casing.

[0015] Furthermore, the battery modules are connected in series to form a battery. The battery pack also includes a connecting component. One end of the connecting component is connected to the power source, and the other end of the connecting component passes through the housing and is mounted on the outer wall of the housing.

[0016] As can be seen from the above technical solutions, this utility model has the following advantages: 1. By installing cooling pipes immersed in coolant inside the battery pack housing, with the inlet and outlet penetrating and fixedly connected to the housing, and at least three cooling units connected in parallel between the primary inlet and outlet pipes, efficient heat exchange of the coolant inside the housing is achieved. This continuously reduces the temperature of the liquid surrounding the battery module, effectively improving the thermal management performance and heat dissipation uniformity of the immersion cooling system, ensuring the safety and lifespan of the battery under high-rate operating conditions. Furthermore, the immersion-coupled direct cooling method, where the cooling pipes are filled with refrigerant instead of the traditional ethylene glycol and water mixture, allows for a phase change in the refrigerant, further improving the coefficient of performance (COP).

[0017] 2. By setting the circulation pipe to consist of at least one parallel circulation sub-pipe, and connecting its two ends to the secondary liquid inlet pipe and the secondary liquid outlet pipe respectively, the liquid is evenly distributed in multiple parallel branches, which effectively enhances the flow capacity and heat dissipation capacity of the cooling sub-unit, reduces the pipe flow resistance and improves the liquid heat conduction rate.

[0018] 3. By connecting at least one auxiliary pipe in parallel to the primary outlet pipe and connecting both ends of the auxiliary pipe to the primary outlet pipe, a redundant configuration of the coolant outflow path is achieved. When the flow resistance of the main outlet pipe is too high or it is blocked, the coolant can be diverted and drained through the auxiliary pipe, thereby improving system stability and cooling reliability and preventing local heat accumulation.

[0019] 4. By setting the cooling pipes so that their projection on the plane where the battery module is located coincides with the projection of all battery modules in the box, the maximum thermal coupling contact area between the cooling pipes and the battery module is achieved, thereby effectively improving the thermal conduction coverage of the coolant on the surface of the battery module and improving the overall temperature uniformity and cooling uniformity of the battery. Attached Figure Description

[0020] To more clearly illustrate the technical solution of this utility model, the drawings used in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of the submersible liquid-cooled battery pack in a specific embodiment of this utility model; Figure 2 This is a partial structural schematic diagram of the submersible liquid-cooled battery pack in a specific embodiment of this utility model; Figure 3 This is a schematic diagram of the cooling pipe structure in a specific embodiment of this utility model; Figure 4 This is a schematic diagram of the battery module structure in a specific embodiment of this utility model; Figure 5 This is a schematic diagram of the structure of the battery cell and adhesive strip in a specific embodiment of this utility model.

[0022] In the diagram: 1. Housing; 2. Top cover; 3. Liquid inlet; 4. Liquid outlet; 5. Liquid injection port; 6. Explosion-proof valve; 7. Connecting assembly; 8. Communication assembly; 9. Cooling pipes; 10. Battery module; 11. End plate; 12. Battery cell; 13. Wiring harness isolation plate; 14. Steel strip; 15. Adhesive strip; 16. Cooling unit; 17. Cooling subunit; 18. Secondary liquid inlet pipe; 19. Circulation sub-pipe; 20. Secondary liquid outlet pipe; 21. Primary liquid inlet pipe; 22. Primary liquid outlet pipe; 23. Auxiliary pipes. Detailed Implementation

[0023] Various embodiments of this disclosure will be described more fully in the following detailed description. This disclosure may have various embodiments, and adjustments and changes may be made therein. However, it should be understood that there is no intention to limit the various embodiments of this disclosure to the specific embodiments disclosed herein, but rather this disclosure should be understood to cover all adjustments, equivalents, and / or alternatives falling within the spirit and scope of the various embodiments of this disclosure.

[0024] To facilitate a clear description of the technical solutions in the embodiments of this application, some terms and technologies involved in the embodiments of this application will be briefly introduced below: In the following, the terms “comprising” or “may include”, which may be used in various embodiments of this disclosure, indicate the presence of the disclosed functions, operations, or elements, and do not limit the addition of one or more functions, operations, or elements. Furthermore, as used in various embodiments of this disclosure, the terms “comprising,” “having,” and their cognates are intended only to indicate a particular feature, number, step, operation, element, component, or combination of the foregoing, and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, elements, components, or combinations of the foregoing, or the possibility of adding one or more combinations of the foregoing.

[0025] In various embodiments of this disclosure, the expression "or" or "at least one of A and / or B" includes any combination or all combinations of the words listed simultaneously. For example, the expression "A or B" or "at least one of A and / or B" may include A, may include B, or may include both A and B.

[0026] The terms used in the various embodiments of this disclosure (such as "first," "second," etc.) may modify various components in the various embodiments, but do not limit the corresponding components. For example, the above terms do not limit the order and / or importance of the components. The above terms are only used for the purpose of distinguishing one component from others. For example, a first user device and a second user device refer to different user devices, although both are user devices. For example, a first component may be referred to as a second component without departing from the scope of the various embodiments of this disclosure, and similarly, a second component may also be referred to as a first component.

[0027] It should be noted that if a description is made of "connecting" one component to another, then the first component can be directly connected to the second component, and a third component can be "connected" between the first and second components. Conversely, when a component is "directly connected" to another component, it can be understood that there is no third component between the first and second components.

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] like Figures 1-5 As shown, this embodiment provides an immersion liquid-cooled battery pack, whose structural design aims to improve the cooling efficiency and thermal management capability of the battery module 10, and enhance the safety and stability of the overall structure.

[0030] The immersion liquid-cooled battery pack includes a housing 1, with a top cover 2 installed at the top of the housing 1 to seal the interior of the housing 1 and prevent coolant evaporation and foreign matter intrusion. The housing 1 contains several battery modules 10, all of which are immersed in the coolant filling the housing 1 to achieve all-around liquid cooling of the battery modules 10.

[0031] The housing 1 is equipped with cooling pipes 9, which are completely submerged in coolant for heat exchange with the coolant. Cooling pipes 9 are used to fill and circulate refrigerant. Cooling pipes 9 include an inlet 3 and an outlet 4 located at the external circulation system connection interface of the housing 1. Both inlet 3 and outlet 4 penetrate the housing 1 and are fixedly connected to it to ensure structural sealing and smooth fluid flow.

[0032] In this embodiment, the housing 1 is also provided with a liquid injection port 5, which is used to inject coolant into the housing 1 during battery pack assembly or maintenance. The liquid injection port 5 is equipped with a sealing cap or a check valve, which can be closed after liquid injection to prevent coolant leakage or gas intrusion, and to ensure the system's sealing and the cleanliness of the coolant.

[0033] In this embodiment, the housing 1 is also equipped with an explosion-proof valve 6, which is used to release overpressure when the internal pressure of the battery pack rises abnormally. The explosion-proof valve 6 is generally installed on the cover 2 of the housing 1, and its structure can be a mechanical pressure relief diaphragm or an automatic opening valve structure. Once the internal pressure of the housing 1 exceeds a set threshold, the explosion-proof valve 6 will automatically open to release the pressure, thereby preventing the battery pack structure from bursting due to high pressure and causing a safety accident, thus improving the overall operational safety.

[0034] In this embodiment, the battery pack is further provided with a communication component 8, which is used to realize signal interaction between the battery pack and an external battery management system (BMS). The communication component 8 may include a communication interface, a communication cable, and a protocol conversion module connected to a host computer system, for real-time transmission of data parameters such as temperature, voltage, current, and fault status, supporting remote monitoring and data recording, and improving intelligent management capabilities and system maintainability.

[0035] In this embodiment, a wire harness isolation plate 13 is also provided inside the housing 1. This wire harness isolation plate 13 is installed between the battery module 10 and the side wall of the housing 1 to isolate the high-voltage wire harness and the signal wire harness, preventing cross-interference caused by the wire harness floating or colliding in the coolant. The wire harness isolation plate 13 is generally made of materials with good insulation and liquid resistance, such as polypropylene or nylon, and has pre-set wire harness fixing slots or wire through holes to improve wiring standardization and electrical safety level.

[0036] The cooling pipe 9 further includes a primary liquid inlet pipe 21 and a primary liquid outlet pipe 22. At least three cooling units 16 are connected in parallel between the primary liquid inlet pipe 21 and the primary liquid outlet pipe 22 to form a multi-channel heat dissipation structure. The two ends of each cooling unit 16 are connected to the primary liquid inlet pipe 21 and the primary liquid outlet pipe 22 respectively, thereby forming a parallel channel structure to realize multi-path circulation of coolant.

[0037] In this embodiment, each cooling unit 16 is composed of at least one cooling sub-unit 17 or several cooling sub-units 17 connected in parallel. The parallel structure between the cooling sub-units 17 further improves the flexibility of local heat dissipation and the scalability of the system.

[0038] The structure of the cooling subunit 17 is as follows: the secondary liquid inlet pipe 18, the circulation pipe and the secondary liquid outlet pipe 20 are connected end to end to form an S-shaped cooling circuit, in which the coolant can fully convect and complete heat exchange.

[0039] Furthermore, the circulation pipeline is composed of at least one circulation sub-pipe 19 connected in parallel. The two ends of each circulation sub-pipe 19 are connected to the secondary liquid inlet pipe 18 and the secondary liquid outlet pipe 20, respectively, forming multiple parallel flow paths, so that the coolant is evenly distributed in each path, improving the overall heat exchange efficiency and reducing flow resistance.

[0040] To enhance the stability and drainage efficiency of the cooling system, at least one auxiliary pipe 23 is connected in parallel to the primary outlet pipe 22. Both ends of the auxiliary pipe 23 are connected to the primary outlet pipe 22. When there is a blockage in the main pipe or the flow rate is unstable, it assists in drainage and improves the safety of system operation.

[0041] In this embodiment, the number of battery modules 10 is at least two, and multiple battery modules 10 are connected in series to meet specific voltage output requirements and improve modular expansion capabilities.

[0042] Each battery module 10 includes several cells 12 arranged side by side. Adhesive strips 15 are provided between adjacent cells 12 to prevent direct contact and friction between cells 12, and to play a role in buffering, spacing and insulation, thereby improving the stability of the cell 12 structure and the consistency of thermal management.

[0043] The battery module 10 also includes end plates 11 disposed at both ends and steel straps 14 for fixing and binding. The steel straps 14 are sleeved on the two end plates 11 and several battery cells 12, effectively constraining the relative displacement of the battery cells 12 in the coolant caused by buoyancy, thermal expansion or vibration, and ensuring the structural integrity and operational safety of the battery module 10.

[0044] In terms of structural layout, the projection of the cooling pipe 9 on the plane where the battery module 10 is located can coincide with the projection of all the battery modules 10 set in the housing 1. That is, the coverage area of ​​the cooling pipe 9 corresponds to the arrangement area of ​​the battery module 10, ensuring that the heat exchange path is evenly distributed around each cell 12, avoiding the existence of heat dissipation dead corners, and improving the overall temperature field balance.

[0045] To enable external power transmission, battery modules 10 are connected in series to form a battery, which is then connected to an external system via a connecting component 7 mounted on the housing 1. One end of the connecting component 7 is connected to the power source, and the other end passes through the housing 1 and is mounted on the outer wall of the housing 1. This ensures stable power output without damaging the top structure of the housing 1, thus ensuring overall sealing and electrical safety.

[0046] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An immersion liquid-cooled battery pack, comprising a housing (1), a top cover (2) provided at the upper end of the housing (1), a plurality of battery modules (10) disposed inside the housing (1), and the housing (1) filled with coolant, characterized in that, The housing (1) is provided with a cooling pipe (9), which is immersed in the coolant. The inlet (3) and outlet (4) of the cooling pipe (9) pass through the housing (1) and are fixedly connected to the housing (1). The cooling pipe (9) is used to fill and circulate refrigerant. The cooling pipe (9) includes a primary inlet pipe (21) and a primary outlet pipe (22). At least three cooling units (16) are connected in parallel between the primary inlet pipe (21) and the primary outlet pipe (22). The two ends of the cooling unit (16) are connected to the primary inlet pipe (21) and the primary outlet pipe (22) respectively.

2. The immersion liquid-cooled battery pack according to claim 1, characterized in that, The cooling unit (16) consists of at least one cooling subunit (17) or several cooling subunits (17) connected in parallel.

3. The immersion liquid-cooled battery pack according to claim 2, characterized in that, The cooling subunit (17) consists of an S-shaped pipeline formed by connecting the two-stage liquid inlet pipe (18), the circulation pipe and the two-stage liquid outlet pipe (20) end to end.

4. The immersion liquid-cooled battery pack according to claim 3, characterized in that, The circulation pipe consists of at least one circulation sub-pipe (19) connected in parallel, with the two ends of the circulation sub-pipe (19) connected to the secondary inlet pipe (18) and the secondary outlet pipe (20), respectively.

5. The immersion liquid-cooled battery pack according to claim 1, characterized in that, At least one auxiliary pipe (23) is connected in parallel to the primary outlet pipe (22), and both ends of the auxiliary pipe (23) are connected to the primary outlet pipe (22).

6. The immersion liquid-cooled battery pack according to claim 1, characterized in that, The number of battery modules (10) is at least two, and each battery module (10) is connected in series.

7. The immersion liquid-cooled battery pack according to claim 6, characterized in that, The battery module (10) contains several cells (12) arranged side by side, with adhesive strips (15) between adjacent cells (12).

8. The immersion liquid-cooled battery pack according to claim 1, characterized in that, The battery module (10) also includes end plates (11) and steel strips (14) at both ends. The steel strips (14) are attached to the two end plates (11) and several cells (12) for binding and fixing.

9. The immersion liquid-cooled battery pack according to claim 1, characterized in that, The projection of the cooling pipe (9) on the plane where the battery module (10) is located can coincide with the projection of all the battery modules (10) installed in the housing (1).

10. The immersion liquid-cooled battery pack according to claim 1, characterized in that, The battery modules (10) are connected in series to form a battery. The battery pack also includes a connecting component (7). One end of the connecting component (7) is connected to the power source, and the other end of the connecting component (7) passes through the housing (1) and is set on the outer wall of the housing (1).

Images