Immersed thermal management device for energy storage battery

Abstract

The utility model discloses an immersed heat management device for an energy storage battery. The immersed heat management device comprises a battery box body and a flow guide plate, the battery box body is used for accommodating and placing a battery module, and the guide plate divides the battery module into an upper layer and a lower layer; a coolant inlet and a coolant outlet are formed in the box body, the coolant inlet and the coolant outlet are formed in the same side of the battery box body, and a coolant flows in from the coolant inlet, flows to the lower layer of the battery module through the upper layer of the battery module and flows out from the coolant outlet. Through the arrangement of the flow guide plate, a coolant preferentially cools the upper layer of the battery module, meanwhile, the tabs are well cooled, then the lower layer of the battery module is cooled through the flow guide effect of the flow guide plate, and a low flow area and a heat accumulation area in the battery module obtain good heat exchange efficiency through the design of flow holes of the flow guide plate; and the problem of non-uniform temperature of the battery is solved.

Description

Technical Field

[0001] The utility model relates to the field of battery thermal management, and more specifically, to an immersion thermal management device for an energy storage battery. Background Art

[0002] To meet the growing demand for energy, the development of renewable energy is crucial. The volatility and intermittent nature of renewable energy sources such as wind and photovoltaics limit their widespread application. Therefore, the research and development of energy storage technology is of great significance to the development of the new energy industry. There are many types of energy storage methods, the main ones being electrochemical and battery energy storage, flywheel energy storage, and compressed air energy storage. Electrochemical energy storage systems based on lithium-ion batteries have become one of the most promising energy storage technologies due to their flexibility, high energy density, and long life. However, heat is inevitably generated during the charging and discharging process, and battery thermal safety issues have become a key issue for batteries, requiring safe thermal management of batteries. When formulating a battery cooling strategy, safe battery operating temperature and battery pack temperature uniformity are two key factors: the safe operating temperature range of lithium-ion batteries is within 15-40°C. When the battery temperature rises above the critical threshold, the electrolyte solvent will reduce its performance and battery life. At the same time, the temperature non-uniformity of lithium-ion batteries will also seriously affect the performance of the battery module. Excessive temperature difference will cause internal short circuits and local hot spot degradation of the battery. The maximum temperature difference of the module should be less than 5°C. At the same time, the uneven temperature distribution inside the battery will affect the rate of electrochemical reactions, resulting in reduced battery performance and shortened battery cycle life.

[0003] Thermal management technologies for traditional energy storage batteries include air cooling, liquid cooling, heat pipe cooling, and phase change material cooling. Air cooling has a simple structure and mature technology. However, due to the poor thermophysical properties of air, air cooling has poor heat dissipation performance. Liquid cold plate cooling has high heat dissipation efficiency and is particularly suitable for large-capacity energy storage power stations, but the complex channel design and flow pattern in the cold plate make research more complicated. Heat pipe cooling allows for flexible design but has low capacity. Phase change material heat dissipation, as a passive cooling method, has the advantages of simplicity, efficiency, and compactness. However, phase change materials cannot be used alone. Air cooling or liquid cold plate cooling is usually integrated into the phase change material system to promote the solidification of the phase change material and recover its latent heat. This constitutes a composite battery thermal management system, but it is usually complex and not conducive to integration.

[0004] To improve the heat exchange efficiency of energy storage battery systems, immersion cooling, also known as liquid direct cooling, is used. The batteries are immersed in the coolant or partially in direct contact with the coolant to minimize the thermal resistance between the batteries and the coolant. This allows heat to be transferred directly to the coolant. This is an efficient cooling method that has the potential to achieve optimal battery pack and battery temperature uniformity.

[0005] However, there are still many problems with battery immersion cooling. Traditional immersion uses insulating solutions such as oils, esters, and fluorinated liquids as coolants, which have problems with low thermal conductivity and poor heat transfer performance. The heat carrying capacity is limited according to the properties of the coolant working fluid, which leads to poor temperature uniformity of the battery module. Traditional coolant inlets and outlets are usually set on both sides of the battery box, with top inlet and bottom outlet or left inlet and right outlet. Low flow areas and heat accumulation areas are easily generated in the battery module, resulting in local excessive temperature. At the same time, there are no measures to dissipate heat from the battery tabs, resulting in uneven temperature of the battery module and high temperature at the battery tabs, resulting in uneven temperature inside the battery. Therefore, it is necessary to improve the thermal management of submerged energy storage batteries in terms of immersion coolant selection and coolant flow channel design. Utility Model Content

[0006] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and to provide an immersion thermal management device for energy storage batteries, so as to mainly solve the problems of battery cells and uneven temperature between battery modules caused by the poor heat carrying capacity of traditional coolant and the traditional coolant inlet and outlet being arranged on both sides of the battery box at the top in and bottom out or at the left in and right out.

[0007] In order to achieve the above purpose, the technical solution of the utility model is:

[0008] An immersion thermal management device for an energy storage battery comprises a battery box and a guide plate; the battery box is used to accommodate a battery module, and the guide plate divides the battery module into two layers, an upper layer and an lower layer; a coolant inlet and a coolant outlet are provided in the box, and the coolant inlet and the coolant outlet are arranged on the same side of the battery box, and the coolant flows from the coolant inlet, flows through the upper layer of the battery module to the lower layer of the battery module, and flows out from the coolant outlet.

[0009] In this way, when thermal management is performed on the immersed module battery, the coolant flows in from the coolant inlet of the battery case, preferentially flows through the upper layer of the battery module, preferentially cools the tabs or the high-temperature side of the battery, and then flows to the lower layer of the battery module through the guide plate for cooling. The coolant is in direct contact with the heat-generating battery for heat dissipation and cooling. Since the coolant inlet and the coolant outlet are arranged on the same side of the battery case, the coolant flow trajectory is a horizontal "U"-shaped flow channel, which can achieve the purpose of reducing the maximum temperature and the maximum temperature difference. At the same time, the addition of the guide plate allows the battery module to be cooled in different areas, so that the coolant in the battery module flows more fully, reducing the occurrence of low flow areas and heat accumulation areas, and further improving the temperature uniformity of the battery module.

[0010] Furthermore, a flow channel is provided on the guide plate, and the coolant flows along the direction of the flow channel.

[0011] Furthermore, the end of the guide plate is not connected to the inner wall of the battery box, and the distance between the end of the guide plate and the inner wall of the battery box is equal to the distance from the side of the last row of batteries in the battery module to the inner wall of the battery box. The coolant flows from top to bottom according to the guide plate structure.

[0012] Furthermore, the end of the guide plate is sealed with the inner wall of the battery box, and guide holes are provided between the end of the guide plate and the center of the last row of batteries in the battery module. The ratio of the number of guide holes in the guide plate to the number of batteries in the last row of the battery module is 1:1; the coolant flows in a top-down direction according to the structure of the guide plate.

[0013] Furthermore, the end of the guide plate is sealed with the inner wall of the battery box, and the guide plate is provided with guide holes at the center intervals of two adjacent rows of batteries in the battery module and at the center of the last row of batteries in the battery module at the end of the guide plate. The ratio of the number of guide holes of the guide plate to the number of batteries in the battery module is 1:1; the coolant flows in a top-down direction according to the structure of the guide plate.

[0014] Furthermore, the coolant is an oil-based phase change microcapsule suspension.

[0015] Furthermore, the guide plate is sealed and bonded to the box body and the battery through an adhesive layer.

[0016] Furthermore, the battery module is the smallest unit module of the battery energy storage system.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The coolant used is an oil-based phase change microcapsule suspension, which has the characteristics of high heat load density. Direct contact with the battery can improve the temperature uniformity of the module battery. Through the setting of the guide plate, the battery module is separated into two layers, the upper layer is connected to the coolant inlet, so that the coolant cools the upper side of the battery first, and at the same time the pole ear is well dissipated. The guide effect of the guide plate is then used to cool the lower side of the battery. Further, through the design of the guide plate flow holes, the low flow area and heat accumulation area in the battery module can obtain better heat exchange effect, thereby solving the problem of uneven battery temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the structure of the energy storage battery immersion thermal management device provided by the utility model accommodating a battery module;

[0020] Figure 2 A schematic structural diagram of the submerged thermal management device for an energy storage battery provided in Example 1;

[0021] Figure 3 Schematic diagram of the guide plate structure in Example 1;

[0022] Figure 4 A schematic structural diagram of the submerged thermal management device for an energy storage battery provided in Example 2;

[0023] Figure 5 Schematic diagram of the guide plate structure in Example 2;

[0024] Figure 6 This is a schematic structural diagram of the energy storage battery immersion thermal management device provided in Example 3;

[0025] Figure 7 Schematic diagram of the guide plate structure in Example 3;

[0026] In the figure: 1. Battery case; 2. Battery module; 3. Guide plate; 31. Guide hole; 4. Coolant inlet; 5. Coolant outlet. DETAILED DESCRIPTION

[0027] The technical solution of the present utility model is further described below with reference to the accompanying drawings and embodiments.

[0028] For ease of understanding and explanation, some structures are hidden in all figures, such as the box cover, box side panels, etc.

[0029] Example 1:

[0030] See Figure 1-3 As shown, the energy storage battery immersion thermal management device provided in this embodiment mainly includes a battery case 1 and a guide plate 3. The battery case 1 is used to accommodate a battery module 2, which is the smallest unit module of the battery energy storage system. The energy storage battery system can be composed of one or more battery modules. The guide plate 3 will be arranged in the battery case 1, and divide the battery module 2 and the battery case 1 into two layers, upper and lower. A coolant inlet 4 and a coolant outlet 5 are provided in the battery case 1. The coolant inlet 4 and the coolant outlet 5 are arranged on the same side of the battery case 1. The coolant flows from the coolant inlet through the upper layer of the battery module to the lower layer of the battery module and flows out from the coolant outlet.

[0031] The guide plate 3 is sealed and bonded to the battery box 1 and the battery 2 through an adhesive layer. A flow channel is provided on the guide plate 3, and the coolant flows along the direction of the flow channel.

[0032] Specifically, in this embodiment, the end of the guide plate 3 is not connected to the battery 2 and the inner wall of the battery box 1. The distance between the end of the guide plate 3 and the inner wall of the battery box 1 is equal to the distance from the side of the rear battery of the battery module to the inner wall of the battery box 1. The coolant flows in a top-down direction according to the setting of the guide plate structure 3, and the coolant is an oil-based phase change microcapsule suspension. In this way, when the immersed module battery is thermally managed, the coolant flows in from the coolant inlet 4 of the upper part of the battery case 1, preferentially flows through the upper layer of the battery module, preferentially cools the tabs or the high-temperature side of the battery, and then flows to the lower layer of the battery module through the end notch of the guide plate 3 for cooling. The coolant finally flows out from the coolant outlet 5 of the lower layer of the battery case. The oil-based phase change microcapsule suspension with high heat load density directly contacts the heat-generating battery for heat dissipation and cooling. The coolant flow trajectory is a horizontal "U"-shaped flow channel, which can achieve the purpose of reducing the maximum temperature and the maximum temperature difference. At the same time, the addition of the guide plate allows the battery module to be cooled in different areas, so that the coolant in the battery module flows more fully, reducing the size of the low flow area and the heat accumulation area, and improving the temperature uniformity of the battery module.

[0033] Example 2:

[0034] This embodiment is basically the same as embodiment 1, except that the end of the guide plate 3 is sealed to the inner wall of the battery case 1, and a guide hole 31 is provided between the end of the guide plate 3 and the center of the last row of batteries in the battery module. The ratio of the number of guide holes 31 to the number of batteries in the last row of the battery module is 1:1. When thermally managing the immersed module battery, the coolant flows in from the coolant inlet 4 in the upper part of the battery case 1, flows through the upper layer of the battery module, preferentially cools the tabs or the high-temperature side of the battery, and then flows to the lower layer of the battery module through the guide hole 31 at the end of the guide plate 3 for cooling. The coolant finally flows out from the coolant outlet in the lower layer of the battery case. The coolant flow trajectory is a horizontal "U"-shaped flow channel, and the oil-based phase change microcapsule suspension with a high heat load density is in direct contact with the heat-generating battery for heat dissipation and cooling. The setting of the guide holes of the guide plate reduces the flow area of ​​the flow from the upper layer of the box to the lower layer of the box, slowing down the flow rate of the coolant from the upper layer to the lower layer of the box, so that the coolant can fully flow and contact with the battery in the upper layer, thereby improving the cooling efficiency and further improving the temperature uniformity of the battery module.

[0035] Example 3:

[0036] This embodiment is basically the same as embodiment 2, except that the end of the guide plate 3 is sealed and connected to the inner wall of the battery case 1, and the guide plate 3 is provided with guide holes 31 at the center intervals of two adjacent rows of batteries in the battery module and at the ends of the guide plate 3 at the centers of the adjacent battery intervals of the battery module and the centers of the last row of batteries in the battery module. The ratio of the number of guide holes 31 of the guide plate to the number of batteries in the battery module is 1:1. When thermal management of the immersed module battery is performed, the coolant flows in from the coolant inlet of the upper layer of the battery case, flows through the upper layer of the battery module, and preferentially cools the tabs or the high-temperature side of the battery, and then flows to the lower layer of the module through the guide holes at the center intervals of the guide plate battery pack and the end guide holes for cooling. The coolant finally flows out from the coolant outlet of the lower layer of the battery case. The coolant flow trajectory is a horizontal double "U"-shaped flow channel, and the oil-based phase change microcapsule suspension with high heat load density is in direct contact with the heat-generating battery for heat dissipation and cooling. The provision of guide holes 31 at the end of guide plate 3 reduces the flow area from the upper layer of the battery case to the lower layer of the case, slowing the flow rate of coolant from the upper layer to the lower layer of the battery case. This ensures that the coolant fully contacts the batteries in the upper layer, improving cooling efficiency. The provision of guide holes 31 at the center of the battery pack further reduces the impact of low flow areas and heat accumulation areas between adjacent rows of batteries, thereby ensuring more complete coolant flow within the battery module and further improving the temperature uniformity of the battery module.

[0037] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications based on the essence of the present invention are intended to be included in the scope of protection of the present invention.

Claims

1. An immersion thermal management device for energy storage batteries, characterized in that: It includes a battery box and a guide plate; the battery box is used to accommodate the battery module, and the guide plate divides the battery module into two layers, an upper layer and an lower layer; a coolant inlet and a coolant outlet are provided in the battery box, and the coolant inlet and the coolant outlet are arranged on the same side of the battery box, and the coolant flows from the coolant inlet into the upper layer of the battery module and flows to the lower layer of the battery module, and flows out from the coolant outlet.

2. The energy storage battery immersion thermal management device according to claim 1, characterized in that: The guide plate is provided with a flow channel, and the coolant flows along the direction of the flow channel.

3. The energy storage battery immersion thermal management device according to claim 2, characterized in that: The end of the guide plate is not connected to the inner wall of the battery box. The distance between the end of the guide plate and the inner wall of the battery box is equal to the distance from the side of the last row of batteries in the battery module to the inner wall of the battery box. The coolant flows from top to bottom according to the guide plate structure.

4. The energy storage battery immersion thermal management device according to claim 2, characterized in that: The end of the guide plate is sealed with the inner wall of the battery box, and a guide hole is provided between the end of the guide plate and the center of the last row of batteries in the battery module. The ratio of the number of guide holes in the guide plate to the number of batteries in the last row of the battery module is 1:

1. The coolant flows from top to bottom according to the structure of the guide plate.

5. The energy storage battery immersion thermal management device according to claim 2, characterized in that: The end of the guide plate is sealed with the inner wall of the battery box. The guide plate is provided with guide holes at the center intervals of two adjacent rows of batteries in the battery module, and at the center of the last row of batteries in the battery module at the end of the guide plate. The ratio of the number of guide holes of the guide plate to the number of batteries in the battery module is 1:

1. The coolant flows in a top-down direction according to the structure of the guide plate.

6. The energy storage battery immersion thermal management device according to any one of claims 2 to 5, characterized in that: The coolant is an oil-based phase-change microcapsule suspension.

7. The energy storage battery immersion thermal management device according to claim 3, characterized in that: The guide plate is sealed and bonded to the battery box and the batteries of the battery module through an adhesive layer.

8. The energy storage battery immersion thermal management device according to claim 1, characterized in that: The battery module is the smallest unit module of the battery energy storage system.

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