A passive-active composite cooling system based on energy storage battery module
By introducing a combined active and passive cooling system into the battery module, and utilizing a combination of liquid cooling plates and heat spreaders, the problems of longitudinal temperature difference and thermal failure of phase change materials in the battery are solved, achieving high energy density and temperature uniformity, and improving the efficiency and safety of battery thermal management.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TIANJIN UNIV
- Filing Date
- 2026-04-29
- Publication Date
- 2026-07-14
AI Technical Summary
Existing battery thermal management systems in energy storage power stations suffer from problems such as large longitudinal temperature differences in batteries, thermal failure of phase change materials, and difficulty in balancing energy density and temperature uniformity. Traditional liquid cooling plate arrangements are complex and costly.
A combined active and passive cooling system is adopted, which arranges liquid cooling plates at the bottom and top of the battery module and sets up heat exchange plates between adjacent battery cells. The heat exchange plates are composed of phase change materials and metal fins. The high thermal conductivity of the metal fins is used to quickly conduct heat, and the flowing coolant quickly removes the heat, resulting in a uniform temperature distribution.
It achieves high energy density and good temperature uniformity in battery modules, delays the thermal failure of phase change materials, improves the overall thermal management efficiency and safety of batteries, and reduces system complexity and cost.
Smart Images
Figure CN122393478A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to battery thermal management, and more particularly to an active-passive combined cooling system based on an energy storage battery module. Background Technology
[0002] To reduce global carbon emissions and strictly control fossil fuel consumption, it is necessary to gradually build a new power system based on new energy sources. This new power system is subject to intermittency and fluctuations due to seasonal and climatic factors, posing a significant challenge to the power grid. Energy storage technology can greatly improve the grid's ability to absorb and regulate renewable energy. Batteries are widely used due to their high energy density, low self-discharge rate, and mature business model framework. However, batteries accumulate a large amount of heat during charging and discharging, affecting battery life and even triggering thermal safety issues.
[0003] Currently, common battery thermal management technologies include air cooling, liquid cooling, phase change cooling, and heat pipes. As the energy density of energy storage power stations continues to increase, the heat removal capacity of traditional air cooling methods is limited, making liquid cooling plates, as an indirect form of liquid cooling, the mainstream approach. Placing liquid cooling plates between battery cells can increase the heat exchange area and improve heat exchange efficiency, but it occupies a large space, reducing the spatial energy density of the battery module. Furthermore, the presence of inlets and outlets on each liquid cooling plate complicates the liquid cooling system, contradicting the current trend of energy storage power stations towards higher energy density. Existing energy storage power stations primarily place liquid cooling plates at the bottom of the battery module. This arrangement can balance thermal management effectiveness and energy density to some extent, but it easily leads to large temperature differences along the vertical axis of the battery. Poor temperature uniformity can cause localized material degradation, thus accelerating the decline in overall battery performance.
[0004] Therefore, in addition to controlling the overall temperature within the optimal operating temperature range of the battery, temperature uniformity is also crucial for battery life and thermal safety. Thus, there is an urgent need for a cooling method that can maintain the spatial energy density of the energy storage battery module while also addressing battery thermal management and improving temperature uniformity.
[0005] Existing Chinese patent CN119560678A discloses a coupled cooling battery thermal management system that utilizes multiple cooling technologies, including flat heat pipes, cold plates, and hybrid fins, to achieve efficient heat dissipation and temperature equalization to a certain extent. However, its structure is complex and its cost is high. Existing Chinese patent CN120300364A employs a stepped phase change material arranged on the side of the battery and a liquid cooling plate arranged on the bottom for thermal management. While this can maintain a balanced internal temperature, the thermal management effect will be affected as the battery continues to heat up and the phase change material undergoes thermal failure. Summary of the Invention
[0006] Purpose of the invention: The purpose of this invention is to provide a combined active and passive cooling system based on an energy storage battery module. It has a simple structure, low cost, and good temperature uniformity. It can solve the problems of large longitudinal temperature difference of batteries and recycling of phase change materials in the thermal management system of energy storage battery modules to a certain extent, and effectively balance the energy density and temperature uniformity of energy storage battery modules.
[0007] Technical solution: A combined active and passive cooling system based on an energy storage battery module, comprising: a battery module, an active module, and a passive module; The battery module includes multiple battery cells with a certain gap between them. Each battery cell includes a battery body and positive and negative tabs symmetrically arranged on its top surface. The active module includes two liquid cooling plates. The lower liquid cooling plate is arranged on the bottom surface of the battery module, and the upper liquid cooling plate is arranged on the top surface of the battery module and located between the positive and negative tabs. The liquid cooling plates have flow channels for coolant to pass through. The passive module includes multiple heat spreaders, which are arranged between adjacent battery cells, with the sides of the heat spreaders in close contact with the surfaces of the left and right battery cells.
[0008] Furthermore, the outer width of the lower liquid cooling plate is the same as the width of the battery body, and the outer width of the upper liquid cooling plate does not exceed the inner distance between the positive and negative tabs on the top surface of the same battery cell.
[0009] Furthermore, the lower liquid cooling plate and the upper liquid cooling plate are respectively provided with coolant inlets and outlets on both sides in the direction of battery cell arrangement. The liquid cooling plate is provided with flow channels for coolant to circulate, and the flow channels are connected to the coolant inlets and outlets.
[0010] Furthermore, the coolant flow direction in the flow channels of the lower liquid cooling plate and the upper liquid cooling plate is always opposite.
[0011] Furthermore, the width of the heat spreader is the same as the width of the battery cell.
[0012] Furthermore, the heat spreader is composed of phase change material and metal fins; the bottom surface of the metal fins is in contact with the lower liquid cooling plate, the top surface is in contact with the upper liquid cooling plate, and the rest are encased inside the phase change material.
[0013] Furthermore, the metal fins should be made of materials with high thermal conductivity, such as aluminum or copper.
[0014] Beneficial effects: (1) The present invention arranges a temperature equalization plate between multiple battery cells and uses phase change material to control the longitudinal temperature difference of the battery, thereby improving the overall temperature uniformity of the battery. (2) The cold plate of the present invention is arranged between the bottom and top positive and negative tabs of the battery module. As an active module, it rapidly removes the heat generated in the entire system through the flowing coolant, thereby controlling the overall maximum temperature of the battery. In addition, the present invention takes into account the problem of non-uniform heat generation of the battery, that is, the temperature near the positive and negative tabs of the battery is relatively high. The cold plate arranged on the top surface of the battery can quickly absorb the heat in the area near the positive and negative tabs, further controlling the overall maximum temperature of the battery. (3) In this invention, the metal fins are wrapped in the phase change material, and the upper and lower sides of the metal fins are in contact with the cold plate. The high thermal conductivity of the metal fins allows the heat absorbed by the phase change material from the battery to be quickly conducted to the cold plate. During the high-rate operation of the battery, the phase change process of the phase change material is effectively delayed, preventing a significant decrease in thermal management effect after the thermal failure of the phase change material. During the low-rate operation of the battery, the thermal performance of the phase change material can be quickly restored. Attached Figure Description
[0015] Figure 1 This is an overall schematic diagram of the present invention; Figure 2 This is a front view of the present invention; Figure 3 This is a schematic diagram of a battery cell of the present invention; Figure 4 This is a schematic diagram of the liquid cooling plate of the present invention; Figure 5 This is a cross-sectional view AA of the liquid cooling plate of the present invention; Figure 6 This is a schematic diagram of the heat spreader of the present invention; In the diagram, 1 is the battery cell, 2 is the active module, 3 is the passive module, 11 is the battery body, 12 is the positive tab, 13 is the negative tab, 21 is the liquid cooling plate, 22 is the liquid cooling plate, 23 is the flow channel, 24 is the coolant inlet and outlet, 4 is the heat spreader, 41 is the phase change material, and 42 is the metal fin. Detailed Implementation
[0016] To make the technical solution of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0017] Example like Figure 1-6 As shown, the present invention provides an active-passive composite cooling system based on an energy storage battery module, comprising a battery module 1, an active module 2, and a passive module 3. The battery module includes multiple battery cells 1; there is a certain gap between each battery cell 1; the battery cell 1 includes a battery body 11 and positive electrode tabs 12 and negative electrode tabs 13 arranged symmetrically on its top surface; The active module 2 includes two liquid cooling plates. The lower liquid cooling plate 21 is arranged on the bottom surface of the battery module, and the upper liquid cooling plate 22 is arranged on the top surface of the battery module and located between the positive electrode tab 12 and the negative electrode tab 13. The liquid cooling plate has a flow channel 23 for coolant to pass through. The passive module 3 includes multiple heat spreaders 4, which are arranged between adjacent battery cells 1. The heat spreaders 31 are in close contact with the surfaces of the left and right battery cells 1 on both sides. The outer width of the lower liquid cooling plate 21 is the same as the width of the battery body 11, and the outer width of the upper liquid cooling plate 22 does not exceed the inner distance between the positive tab 12 and the negative tab 13 on the top surface of the same battery cell 1. The lower liquid cooling plate 21 and the upper liquid cooling plate 22 are respectively provided with coolant inlet and outlet 24 on both sides of the battery cell 1 in the direction of arrangement. The liquid cooling plate has a flow channel 15 for coolant to flow, and the flow channel 23 is connected to the coolant inlet and outlet 24. The coolant flows in opposite directions in the flow channels 23 of the lower liquid cooling plate 21 and the upper liquid cooling plate 22. The width of the heat spreader 4 is the same as the width of the battery cell 1; The heat exchange plate 4 is composed of phase change material 41 and metal fins 42; the bottom surface of the metal fins 42 is in contact with the lower liquid cooling plate 21, the top surface is in contact with the upper liquid cooling plate 22, and the rest is wrapped inside the phase change material 41. Metal fins 42 should be made of materials with high thermal conductivity, such as aluminum or copper. In this invention, a combined active and passive cooling system based on an energy storage battery module is disclosed. During operation, multiple battery cells 1 within the battery module generate heat unevenly, causing the temperature of each battery cell 1 to rise and exhibit a non-uniform distribution where the upper part of the cell is hotter than the lower part. A portion of the heat generated by the battery module is directly absorbed by the active module 2, while the remainder is first absorbed by the passive module 3 and then transferred to the active module 2. The passive module 3 includes multiple heat spreaders, each composed of phase change material 41 and metal fins 42. The sides of the heat spreader 4 are in close contact with the surfaces of adjacent battery cells 1 to absorb heat from the battery module. By utilizing the characteristic of the phase change material 41 to maintain a stable temperature during the heat absorption and phase change process, the heat uniformity of the battery cells 1 is improved. The metal fins 42 are wrapped inside the phase change material 41 and are in close contact with the active module 2 on the top and bottom sides. Utilizing the high thermal conductivity of the metal, the heat from the phase change material 41 is quickly transferred to the active module 2. During the high-rate operation of the battery, the phase change process of the phase change material 41 is effectively delayed, preventing a significant decrease in thermal management performance due to thermal failure of the phase change material 41. During the low-rate operation of the battery, the thermal performance of the phase change material 41 can be quickly restored. The active module 2 includes two liquid cooling plates. The lower liquid cooling plate 21 is arranged on the bottom surface of the battery module, and the upper liquid cooling plate 22 is arranged on the top surface of the battery module and located between the positive tab 12 and the negative tab 13. The liquid cooling plate has a flow channel 23 for the coolant to pass through. As the active module 2, the flowing coolant quickly removes the heat generated in the entire system, thereby controlling the overall maximum temperature of the battery. In addition, the present invention takes into account the problem of non-uniform heat generation of the battery, that is, the temperature near the positive and negative tabs of the battery is relatively high. The cooling plate arranged on the top surface of the battery can quickly absorb the heat in the area near the positive and negative tabs, further controlling the overall maximum temperature of the battery.
[0018] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.
Claims
1. A combined active and passive cooling system based on an energy storage battery module, characterized in that, include: Battery modules, active modules, and passive modules; The battery module includes multiple battery cells (1), with a certain gap between the battery cells (1). Each battery cell (1) includes a battery body (11) and positive electrode tabs (12) and negative electrode tabs (13) arranged symmetrically on its top surface. The active module (2) includes two liquid cooling plates. The lower liquid cooling plate (21) is arranged on the bottom surface of the battery module, and the upper liquid cooling plate (22) is arranged on the top surface of the battery module and located between the positive electrode tab (12) and the negative electrode tab (13). The liquid cooling plate has a flow channel (23) for coolant to pass through. The passive module (3) includes multiple heat spreaders (4) and is arranged between adjacent battery cells (1). The heat spreaders (31) are in close contact with the surfaces of the left and right battery cells (1) on both sides.
2. The active-passive composite cooling system based on an energy storage battery module according to claim 1, characterized in that, The outer width of the lower liquid cooling plate (21) is the same as the width of the battery body (11), and the outer width of the upper liquid cooling plate (22) does not exceed the inner distance between the positive tab (12) and the negative tab (13) on the top surface of the same battery cell (1).
3. The active-passive composite cooling system based on an energy storage battery module according to claim 2, characterized in that, The lower liquid cooling plate (21) and the upper liquid cooling plate (22) are respectively provided with coolant inlet and outlet (24) on both sides of the battery cell (1) arrangement direction. The liquid cooling plate is provided with a flow channel (15) for coolant to flow. The flow channel (23) is connected to the coolant inlet and outlet (24).
4. The active-passive composite cooling system based on an energy storage battery module according to claim 3, characterized in that, The coolant flow direction in the flow channel (23) of the lower liquid cooling plate (21) and the upper liquid cooling plate (22) is always opposite.
5. The active-passive composite cooling system based on an energy storage battery module according to claim 1, characterized in that, The width of the heat spreader (4) is the same as the width of the battery cell (1).
6. The active-passive composite cooling system based on an energy storage battery module according to claim 1, characterized in that, The heat exchange plate (4) is composed of phase change material (41) and metal fins (42); the bottom surface of the metal fins (42) is in contact with the lower liquid cooling plate (21), the top surface is in contact with the upper liquid cooling plate (22), and the rest is wrapped inside the phase change material (41).
7. The active-passive composite cooling system based on an energy storage battery module according to claim 6, characterized in that, The metal fins (42) should be made of materials with high thermal conductivity, such as aluminum or copper.