Liquid cooling energy storage battery system

Abstract

The utility model relates to a liquid cooling energy storage battery system, which belongs to the technical field of lithium ion battery pack liquid cooling energy storage, and comprises a bottom cooling plate, a battery cell group arranged on the bottom cooling plate and a pole column cooling plate arranged at the top of the battery cell group, and cooling liquid passes through the bottom cooling plate and the pole column cooling plate to take away heat of the battery cell group; a blister CCS plate is arranged at the top of the battery cell group, and a pole cooling plate limiting groove matched with the pole cooling plate is formed in the blister CCS plate so as to fix the pole cooling plate at the top of the battery cell group. According to the utility model, the upward bottom heat dissipation surface of the pole of the battery cell is changed into the combination of pole heat dissipation and bottom heat dissipation, so that the heat dissipation efficiency of the cold plate is improved. In addition, the battery cell pole is in contact with the cold plate, and the battery cell pole, the bottom of the battery cell and the cold plate are assembled into the battery pack, so that the heat dissipation capability can be improved, the volume utilization rate can be increased, and the safety of the battery pack is remarkably enhanced.

Description

TECHNICAL FIELD

[0001] The utility model belongs to lithium ion battery pack liquid cooling energy storage technical field, especially a kind of liquid cooling energy storage battery system. BACKGROUND

[0002] Lithium ion battery pack is the core component of energy storage system, and the quality of the battery cell as the key material of the battery pack directly affects the overall consistency and reliability of the energy storage system. The performance and safety of the battery cell are closely related to the working temperature. High or low working temperature will lead to the degradation of battery cell life and performance.

[0003] Studies have shown that the optimal working temperature range of lithium iron phosphate battery cell is 20℃ to 45℃, and the battery cell power will significantly decay when it exceeds 45℃. Therefore, the working temperature of the battery cell should be strictly controlled between 25℃ and 40℃, to ensure that the temperature difference between single battery cells does not exceed 5℃, and the highest safety temperature should not exceed 55℃. In low temperature environment, the activity of the battery cell electrolyte decreases, and the ion diffusion speed slows down, leading to the increase of the battery cell internal resistance and the decrease of the discharge capacity. When the temperature is lower than -20℃, the charging and discharging process of the battery cell will become difficult. When the temperature is too high, the internal reaction rate of the battery cell increases, generating a large amount of heat. Long time high temperature work will reduce the capacity and charging and discharging efficiency of the battery, and even may cause safety accidents. Therefore, the battery cell needs a suitable temperature range to achieve high performance work.

[0004] In recent years, the research focus of domestic lithium ion battery pack liquid cooling energy storage field is concentrated on the heat dissipation method of using liquid cooling plate at the bottom of the battery pack. The principle is to take away the heat through the contact between the bottom of the battery cell and the liquid cooling plate. The liquid cooling takes away the heat generated inside the battery through the continuous flow of cooling medium. The high thermal conductivity of the liquid medium can reduce the temperature of the battery pack to a suitable range in a short time and ensure the temperature uniformity inside the battery box. This method has been widely used in the field of lithium ion battery pack liquid cooling energy storage.

[0005] Although the liquid cooling plate dissipates heat through the contact area at the bottom of the battery pack, under high power, this heat dissipation method is difficult to effectively take away the heat of the battery pack, resulting in poor cooling effect, insufficient heat dissipation efficiency, uneven temperature, and further affecting the life of the battery cell. UTILITY MODEL CONTENTS

[0006] The utility model aims to provide a liquid cooling energy storage battery system using battery cell pole cooling and bottom cooling method to improve the heat dissipation capacity and volume utilization, improve safety, improve heat dissipation efficiency and meet the 1C charging and discharging capacity of the battery pack.

[0007] To achieve the above objectives, the present invention provides a liquid-cooled energy storage battery system, including a bottom cooling plate, a cell assembly disposed on the bottom cooling plate, and an electrode cooling plate disposed on top of the cell assembly. Coolant passes through the bottom cooling plate and the electrode cooling plate to remove heat from the cell assembly. A vacuum-formed CCS plate is provided on top of the cell assembly, and the vacuum-formed CCS plate has an electrode cooling plate limiting groove adapted to the electrode cooling plate to fix the electrode cooling plate to the top of the cell assembly.

[0008] Preferably, the pole cooling plate is an integrated serpentine cooling plate.

[0009] Preferably, the battery cell assembly includes multiple square battery cells, and the coolant flow channels on the electrode cooling plate through which the coolant flows correspond to the positions of the electrode plates on the square battery cells.

[0010] Preferably, the bottom cooling plate and the battery cell assembly are assembled into a battery pack at the bottom using structural thermally conductive adhesive.

[0011] Preferably, the inlet and outlet of the electrode cooling plate are located on the same side of the battery cell assembly.

[0012] Preferably, the battery cell assembly has a panel on its side, and the panel has two openings for the water inlet and the water outlet of the electrode cooling plate to pass through, respectively.

[0013] Preferably, the bottom cooling plate extends outward on one side of the battery cell assembly, and a bottom cooling plate inlet and a bottom cooling plate outlet are provided in the extended portion.

[0014] Preferably, the bottom cooling plate inlet, the bottom cooling plate outlet, the pole cooling plate inlet, and the pole cooling plate outlet are located on the same side of the battery cell assembly.

[0015] Preferably, the vacuum-formed CCS board includes an aluminum busbar welded to the square battery cell.

[0016] Preferably, the vacuum-formed CCS board further includes a bottom and a top cover that are fixedly connected to each other, and the pole cooling plate limiting groove is provided on the top cover.

[0017] In summary, this utility model has the following beneficial technical effects:

[0018] 1. By assembling the battery pack in the form of contact between the cell terminals and the cold plate, and the bottom of the cell plus the cold plate, the heat dissipation capacity and volume utilization are improved, and the safety is greatly enhanced.

[0019] 2. By increasing the heat dissipation of the cell terminals, the heat dissipation efficiency can be greatly improved, meeting the 1C charge and discharge capacity of the battery pack. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the liquid-cooled energy storage battery system of this utility model, omitting the thermoformed CCS plate and the panel;

[0021] Figure 2 This is a schematic diagram of the liquid-cooled energy storage battery system of this utility model, omitting the bottom cooling plate;

[0022] Figure 3 This is a schematic diagram of the structure of a vacuum-formed CCS plate in a liquid-cooled energy storage battery system according to this utility model.

[0023] Reference numerals: 1. Square battery cell; 2. Outlet of terminal cooling plate; 3. Outlet of bottom cooling plate; 4. Bottom cooling plate; 5. Inlet of bottom cooling plate; 6. Inlet of terminal cooling plate; 7. Terminal cooling plate; 8. Vacuum-formed CCS board; 9. Limiting groove of terminal cooling plate; 10. Panel. Detailed Implementation

[0024] 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.

[0025] This utility model discloses a liquid-cooled energy storage battery system, which includes seven parts: a terminal cooling plate inlet 6, a bottom cooling plate 4, a terminal cooling plate 7, a cell assembly, a terminal cooling plate outlet 2, a bottom cooling plate outlet 3, and a bottom cooling plate inlet 5.

[0026] Coolant enters the terminal cooling plate 7 and the bottom cooling plate 4 through the terminal cooling plate inlet 6 and the bottom cooling plate inlet 5 respectively to dissipate heat from the battery cell assembly. The coolant carries away heat through the cooling plate flow channels and the entire cooling plate. The battery cell assembly and the bottom cooling plate 4 are assembled into a battery pack at the bottom with structural thermally conductive adhesive.

[0027] Specifically, this utility model includes a square bottom cooling plate 4, a battery cell assembly disposed on the bottom cooling plate 4, and a terminal cooling plate 7 laid on top of the battery cell assembly; the battery cell assembly is composed of multiple square battery cells 1 arranged neatly; the terminal cooling plate 7 adopts an integrated serpentine cooling plate, and the coolant flow channel on the terminal cooling plate 7 for coolant to flow through corresponds to the position of the electrode plate on the terminal of the square battery cell 1. The terminal cooling plate inlet 6 and the terminal cooling plate outlet 2 of the terminal cooling plate 7 are both located on the same side of the battery cell assembly; the bottom cooling plate 4 extends outward on one side of the battery cell assembly, and the bottom cooling plate inlet 5 and the bottom cooling plate outlet 3 are provided in the extended part; preferably, the bottom cooling plate inlet 5, the bottom cooling plate outlet 3, the terminal cooling plate inlet 6, and the terminal cooling plate outlet 2 are all located on the same side of the battery cell assembly.

[0028] A vacuum-formed CCS plate 8 is laid flat on top of the battery cell assembly. The vacuum-formed CCS plate 8 has a terminal cooling plate limiting groove 9 that matches the terminal cooling plate 7 to fix the terminal cooling plate 7 to the top of the battery cell assembly. The battery cell assembly has a panel 10 on the side where the terminal cooling plate inlet 6 and terminal cooling plate outlet 2 are located. The panel 10 has holes through which the terminal cooling plate inlet 6 and terminal cooling plate outlet 2 can pass. The terminal cooling plate outlet 2 and terminal cooling plate inlet 6 are fixed by the slot of the front plug panel 10. The vacuum-formed CCS plate 8 includes an aluminum busbar, a base plate, and a top cover. The connection between the aluminum busbar in the vacuum-formed CCS plate 8 and the square battery cell 1 is achieved by welding. This connection method is not only strong and reliable, but also ensures good electrical conductivity. The top cover and the base plate are fastened with screws. The top cover has a terminal cooling plate limiting groove 9, which cooperates with the terminal cooling plate limiting groove 9 of the vacuum-formed CCS plate 8 for limiting and fixing.

[0029] It should be noted that the bottom heat dissipation method of the battery cell assembly can use cooling plates of different shapes to replace the square bottom cooling plate 4, and the terminal heat dissipation method of the battery cell assembly can use cooling plates of different shapes to replace the integrated serpentine cooling plate. The positions of the terminal cooling plate inlet 6, the bottom cooling plate inlet 5, the terminal cooling plate outlet 2, and the bottom cooling plate outlet 3 can be changed according to specific needs.

[0030] To improve heat dissipation efficiency and cooling effect, this invention utilizes a cold plate in contact with the terminal post for both terminal post heat dissipation and bottom heat dissipation. Specifically, the bottom heat dissipation surface of the square cell 1, with the terminal post facing upwards, is changed to a combination of terminal post heat dissipation and bottom heat dissipation, thereby improving the heat dissipation efficiency of the cold plate. Furthermore, by assembling the cell terminal post into a battery pack together with the cell bottom and the cold plate, not only is heat dissipation capacity improved, but volume utilization is also increased, significantly enhancing the safety of the battery pack.

[0031] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A liquid-cooled energy storage battery system, characterized in that, The battery pack includes a bottom cooling plate (4), a battery cell assembly on the bottom cooling plate (4), and a terminal cooling plate (7) on top of the battery cell assembly. Coolant passes through the bottom cooling plate (4) and the terminal cooling plate (7) to remove heat from the battery cell assembly. A vacuum-formed CCS plate (8) is provided on top of the battery cell assembly. The vacuum-formed CCS plate (8) has a terminal cooling plate limiting groove (9) that is adapted to the terminal cooling plate (7) to fix the terminal cooling plate (7) to the top of the battery cell assembly.

2. The liquid-cooled energy storage battery system according to claim 1, characterized in that, The pole cooling plate (7) is an integrated serpentine cooling plate.

3. The liquid-cooled energy storage battery system according to claim 2, characterized in that, The battery cell assembly includes multiple square battery cells (1), and the coolant flow channel on the electrode cooling plate (7) through which the coolant flows corresponds to the position of the electrode plate on the electrode post of the square battery cell (1).

4. The liquid-cooled energy storage battery system according to claim 1, characterized in that, The bottom cooling plate (4) and the battery cell assembly are assembled into a battery pack at the bottom using structural thermally conductive adhesive.

5. The liquid-cooled energy storage battery system according to claim 1, characterized in that, The inlet (6) and outlet (2) of the electrode cooling plate (7) are located on the same side of the battery cell assembly.

6. The liquid-cooled energy storage battery system according to claim 5, characterized in that, The battery cell assembly has a panel (10) on its side, and the panel (10) has two openings for the inlet (6) of the electrode cooling plate and the outlet (2) of the electrode cooling plate to pass through respectively.

7. A liquid-cooled energy storage battery system according to claim 6, characterized in that, The bottom cooling plate (4) extends outward on one side of the battery cell assembly, and a bottom cooling plate inlet (5) and a bottom cooling plate outlet (3) are provided in the extended portion.

8. A liquid-cooled energy storage battery system according to claim 7, characterized in that, The bottom cooling plate inlet (5), the bottom cooling plate outlet (3), the pole cooling plate inlet (6), and the pole cooling plate outlet (2) are located on the same side of the battery cell assembly.

9. A liquid-cooled energy storage battery system according to claim 3, characterized in that, The vacuum-formed CCS board (8) includes an aluminum busbar welded to the square battery cell (1).

10. A liquid-cooled energy storage battery system according to claim 9, characterized in that, The vacuum-formed CCS plate (8) also includes a bottom and a top cover that are fixedly connected to each other, and the pole cooling plate limiting groove (9) is provided on the top cover.

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