High-capacity liquid cooling energy storage battery pack

Abstract

The utility model belongs to the technical field of power batteries, and particularly relates to a high-capacity liquid cooling energy storage battery pack which comprises a box body, a battery cell module, a flexible circuit board and a liquid cooling plate, the battery cell module, the flexible circuit board and the liquid cooling plate are arranged in the box body, the flexible circuit board is arranged at the top of the battery cell module, and the liquid cooling plate is arranged at the bottom of the battery cell module; and a lithium iron phosphate cell is arranged in the cell module. Through the standardized structural design of the battery cells and the adoption of high-capacity battery materials, battery clusters with different electric quantities and sizes can be formed through flexible series connection or parallel connection, and the requirements of different energy storage systems are met. And meanwhile, the aerogel arranged between the battery cells or between the battery cells and the liquid cooling plate has the effects of heat insulation, buffering and flame retardance while improving the stability. The cooling channel of the liquid cooling plate is designed, so that the heat dissipation efficiency is improved, and the service life of the battery cell is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model belongs to power battery technical field, concretely relates to a high capacity liquid cooling energy storage battery pack. BACKGROUND

[0002] In recent years, with the gradual depletion of petrochemical energy, energy storage technology has become the focus of research. The energy storage system is the core of energy storage technology, and the battery pack is the key component of the energy storage system. A large amount of heat is generated during the charging and discharging process of the battery pack, and the heat accumulation will affect the charging and discharging rate, life and consistency of the battery pack.

[0003] The heat dissipation mode of the battery pack includes air cooling and liquid cooling, and the air cooling needs to leave out the air duct, and the energy / space ratio is lower than that of the liquid cooling. For the traditional liquid-cooled battery pack, the space inside is filled with battery cells, but the capacity of the battery cells is generally 280Ah or 314Ah, and the capacity is difficult to meet the demand of the energy storage system for high energy density and long cycle life of the battery cells. In addition, the current battery pack lacks space to arrange fire extinguishing devices, and it is difficult to extinguish the flame after thermal runaway. At the same time, the silica gel foam arranged between the battery cells or the battery cells and the liquid cooling plate only has a buffering effect without a flame-retardant effect; and the length of the flow channel in the liquid cooling plate is relatively short, and the heat dissipation effect is poor. SUMMARY

[0004] The utility model aims at providing a high capacity liquid cooling energy storage battery pack, which can be flexibly connected in series or parallel to form battery clusters of different capacities and sizes by standardizing the structure of the battery cells and using high-capacity battery materials, thereby meeting the needs of different energy storage systems. At the same time, the aerogel arranged between the battery cells or the battery cells and the liquid cooling plate improves stability while playing a role in heat insulation, buffering and flame retardation. The cooling channel of the liquid cooling plate is designed to improve the heat dissipation efficiency and the service life of the battery cells.

[0005] In order to achieve the above-mentioned purpose, the utility model is realized through the following technical scheme:

[0006] The embodiment of the utility model provides a high capacity liquid cooling energy storage battery pack, which comprises a box body and a battery cell module, a flexible circuit board and a liquid cooling plate built-in the box body, the flexible circuit board is arranged at the top of the battery cell module, and the liquid cooling plate is arranged at the bottom of the battery cell module; the battery cell module is provided with lithium iron phosphate battery cells.

[0007] In some other embodiments, the box body is a rectangular box body, comprising a box body upper cover, a box body lower cover and side plates arranged around the box body, the side plates comprise horizontal side plates and vertical side plates, the horizontal side plates are arranged horizontally, the vertical side plates are arranged vertically, and the horizontal side plates and the vertical side plates are vertically connected.

[0008] In some other embodiments, the vertical side plate is provided with a plug interface, the plug interface includes a first plug interface and a second plug interface, the first plug interface is provided with a panel, the panel is provided with a power plug and a communication plug;

[0009] The second plug interface is provided with a maintenance cover plate, a safety valve and a fire sprinkler.

[0010] In some other embodiments, a sealing ring is arranged between the upper cover of the box body and the flexible circuit board, the flexible circuit board is a rectangular plate and is made of FPC.

[0011] In some other embodiments, the battery cell module has a rectangular structure and includes battery cells, connectors and a battery management system, the number of the battery cells is several, the battery cells are connected in series or in parallel through the connectors, the battery management system is arranged on the battery cells, and the battery cells are 628 Ah capacity lithium iron phosphate battery cells.

[0012] In some other embodiments, the connector includes end plates, steel belts and soft connection copper bars, the end plates are vertically arranged on the four side edges of the battery cells, the steel belts are horizontally arranged on the top and bottom of the four sides of the battery cells and are arranged outside the end plates, and the soft connection copper bars are arranged on the surfaces of adjacent battery cells.

[0013] In some other embodiments, a heat-conducting gel is arranged between the liquid cooling plate and the battery module, and the heat-conducting gel has a heat conductivity of 2 W / (m·K).

[0014] In some other embodiments, the liquid cooling plate includes an upper cover plate, a lower cover plate and a frame, the frame is arranged between the upper cover plate and the lower cover plate, the upper cover plate, the lower cover plate and the frame are all rectangular plates, the size of the upper cover plate and the lower cover plate is the same and is smaller than the size of the frame.

[0015] In some other embodiments, the frame is provided with a plurality of shunt bars, a liquid inlet and a liquid outlet, the frame includes vertical frames and horizontal frames, the vertical frames and the horizontal frames are vertically connected, the shunt bars are horizontally arranged inside the frame, and the liquid inlet and the liquid outlet are arranged on the two vertical frame sides of the frame and are oppositely arranged.

[0016] In some other embodiments, the space surrounded by the upper cover plate, the lower cover plate and the frame constitutes a cavity of the liquid cooling plate, the shunt bars divide the cooling cavity into a plurality of liquid cooling flow channels connected in sequence, the two ends of the liquid cooling flow channel are connected with the liquid inlet and the liquid outlet arranged on the two vertical frame sides of the frame, the surface of the liquid cooling flow channel is provided with heat dissipation fins, the heat dissipation fins are connected with the upper cover plate and the lower cover plate, and the liquid cooling flow channel is filled with a cooling liquid, and the cooling liquid is an ethylene glycol aqueous solution.

[0017] The beneficial effects of the above embodiments of the utility model are as follows:

[0018] (1) The utility model selects the battery monomer of high energy density, long cycle life, such as high performance lithium iron phosphate battery core, the previous battery core capacity (280Ah, 314Ah) increases one time and the adjacent battery core surface between the air gel does the battery core interval, to improve the impact resistance between the battery core, strengthens the buffering effect and the flame retardant characteristic between the battery core, effectively prevents the thermal runaway and the explosion of battery pack after the battery core fire.

[0019] (2) The utility model discloses the optimized liquid cooling pipeline, selects the cooling liquid and liquid cooling board and the battery core between the laying heat conduction gel of high thermal conductivity coefficient, low corrosiveness, and the flow channel is series flow channel, through increasing the length of flow channel, equivalent to the traditional two liquid cooling board is combined into one, forms a super long flow channel on the longitudinal length, is the two times of general flow channel, and the heat dissipation fin is designed on the surface of liquid cooling pipeline, improves the heat dissipation area and effect of cooling liquid.

[0020] (3) The utility model discloses the state parameter of real-time monitoring battery, such as voltage, current, temperature etc.

[0021] (4) The utility model discloses the battery module adopts standard modular design, and the battery pack is designed as the standard module with unified specification, interface and connection mode, so that the maintenance, replacement and system extension and upgrading of battery are facilitated.

[0022] (5) The utility model discloses the weight and volume of battery pack are reduced significantly by closely integrating each component of battery pack, and the energy efficiency and endurance of battery pack are improved, the space occupied by installation is saved, and the overall structure of energy storage system is more compact and simple. BRIEF DESCRIPTION OF DRAWINGS

[0023] The drawings accompanying the specification of the utility model form a part of the utility model and serve to provide further understanding of the utility model, and the illustrative embodiments of the utility model and their descriptions serve to explain the utility model, and do not constitute an improper limitation on the utility model.

[0024] Figure 1 It is the schematic diagram of the internal structure of the battery pack of the utility model;

[0025] Figure 2 It is the structural schematic diagram of the battery core module of the utility model;

[0026] Figure 3 It is the structural schematic diagram of the liquid cooling board of the utility model;

[0027] Figure 4It is the structure schematic view of the left view of the battery cell module of the utility model;

[0028] The schematic view is only for illustration;

[0029] The battery cell module 1, the flexible circuit board 2, the liquid cooling plate 3, the box upper cover 4, the panel 5, the power connector 6, the communication connector 7, the maintenance cover plate 8, the safety valve 9, the fire sprinkler 10, the end plate 11, the steel belt 12, the soft connection copper bar 13, the aerogel 14, the fire detector 15, the upper cover plate 16, the lower cover plate 17, the frame 18 and the liquid cooling runner 19 are arranged in the box. DETAILED DESCRIPTION

[0030] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the utility model. Unless otherwise specified, all technical and scientific terms used in the utility model have the same meaning as that generally understood by ordinary skilled persons in the technical field to which the utility model belongs.

[0031] Embodiment 1

[0032] In a typical embodiment of the utility model, as shown in the figure, Figure 1 A high-capacity liquid-cooled energy storage battery pack is provided, which comprises a box and a battery cell module 1, a flexible circuit board 2 and a liquid cooling plate 3 built-in the box. The flexible circuit board 2 is arranged at the top of the battery cell module 1, and the liquid cooling plate 3 is arranged at the bottom of the battery cell module 1.

[0033] The box is a rectangular box, which comprises a box upper cover 4, a box lower cover and side plates arranged around the box. The side plates comprise horizontal side plates and vertical side plates, the horizontal side plates are arranged in the horizontal direction of the box, the vertical side plates are arranged in the vertical direction of the box, and the horizontal side plates and the vertical side plates are arranged vertically. The vertical side plates are provided with connector interfaces, and the connector interfaces comprise first connector interfaces and second connector interfaces. As shown in the figure, Figure 4 The first connector interfaces are provided with a panel 5, the panel 5 is provided with a power connector 6 and a communication connector 7, the power connector 6 is arranged on one side of the panel 5, and the communication connector 7 is arranged on the other side of the panel 5. The power connector 6 is used for connecting with an external power supply or load. The communication connector 7 is used for communication between the battery pack and other systems or devices.

[0034] The second connector interfaces are provided with a maintenance cover plate 8, a safety valve 9 and a fire sprinkler 10. The maintenance cover plate 8 is arranged on the surface of the second connector interfaces and can be detachably connected. The safety valve 9 is arranged below the fire sprinkler 10. The safety valve 9 is used for opening exhaust pressure reduction to avoid explosion. The fire sprinkler 10 is used for spraying perfluorohexone extinguishing agent.

[0035] A sealing ring 5 is arranged between the upper cover 4 and the flexible circuit board 2, and is used to improve the sealing effect between the upper cover 4 and the flexible circuit board 2, so as to prevent moisture, dust and the like in the environment from entering the box body; meanwhile, the reliability and durability of the flexible circuit board 2 are enhanced.

[0036] The flexible circuit board 2 is a rectangular plate and is made of FPC. The circuit arranged on the flexible circuit board 2 can monitor the battery state, protect the battery safety and optimize the battery performance.

[0037] The battery cell module 1 is of a rectangular structure and comprises battery cells, connectors and a battery management system. The number of the battery cells is several, which are connected in series or in parallel through the connectors, so as to realize flexible configuration to form battery clusters with different electric quantities and sizes, and meet the needs of different energy storage systems.

[0038] The connector comprises an end plate 11, a steel belt 12 and a soft connection copper bar 13. The end plate 11 is vertically arranged on the four sides of the battery cell. The steel belt 12 is horizontally arranged on the top and bottom of the four sides of the battery cell and is arranged outside the end plate 11. The soft connection copper bar 13 is arranged on the surface of the adjacent battery cell, so as to provide flexible conductive connection between the battery cell modules, reduce the influence of vibration and impact on the battery while transmitting current. An aerogel 14 is arranged between the adjacent battery cells. The aerogel 14 is used as a spacing between the battery cells to improve the impact resistance between the battery cells and strengthen the buffering effect between the battery cells. The aerogel 14 itself has a flame retardant property and can resist high temperature of 1,000 degrees Celsius and is not easy to burn. The aerogel 14 can effectively prevent thermal runaway and explosion of the battery pack after the battery cell catches fire.

[0039] As shown in FIG. 1, Figure 2 The battery cell is a battery monomer with high energy density and long cycle life, such as a high-performance iron lithium phosphate battery cell. The battery cell used at present has a capacity of 628 Ah, which is doubled compared with the previous battery cell capacity (280 Ah and 314 Ah). A fire detector 15 is arranged on the battery cell. The fire detector 15 is used to detect carbon monoxide and smoke in real time, can capture the signal released by the battery module in the initial stage of thermal runaway at an early stage, and can realize module-level fire extinguishing by spraying perfluorohexone extinguishing agent through the fire sprinkler 10 controlled by the battery management system. The battery cell comprises positive and negative electrode plates, a separator, a tab, a packaging film and electrolyte. The tab is made by a cutting tab process, which is more reasonable in space utilization and has smaller surface undulations than a rubbing and pressing tab, and is beneficial to improving the capacity of the battery cell. The packaging film is an aluminum shell. Laser welding process is used for welding the tab and the packaging film, so as to improve the overcurrent capacity and heat dissipation performance of the battery cell.

[0040] The battery management system (BMS) is connected with the battery cell through a battery data acquisition board, various sensors are equipped on the battery data acquisition board, the BMS monitors the voltage, temperature and current and other parameters of the battery cell at any time, carries out battery state estimation and balance control, so as to avoid overcharging, overdischarging, overtemperature and other conditions, and carries out data interaction with an external system through a communication connector 7.

[0041] The liquid cooling plate 3 and the battery module 1 are provided with a heat-conducting gel, the heat-conducting coefficient of the heat-conducting gel is 2 W / (m*K), and the bottom of the battery cell can effectively remove air, so that good filling and heat-conducting effects are achieved.

[0042] As shown in Figure 3 The liquid cooling plate 3 includes an upper cover plate 16, a lower cover plate 17, a frame 18, a liquid cooling flow channel 19 and a heat dissipation fin. The frame 18 is arranged between the upper cover plate 16 and the lower cover plate 17, and the upper cover plate 16, the lower cover plate 17 and the frame 18 are all rectangular plates, and the size of the upper cover plate 16 and the lower cover plate 17 is the same but smaller than the size of the frame 18. A plurality of shunt bars, a liquid inlet and a liquid outlet are arranged on the frame 18. The frame 18 includes vertical frames and horizontal frames, and the vertical frames and the horizontal frames are vertically connected. The shunt bars are horizontally arranged in the interior of the frame 18, and the liquid inlet and the liquid outlet are arranged on the two vertical frame sides of the frame 18 and oppositely arranged.

[0043] The space surrounded by the upper cover plate 16, the lower cover plate 17 and the frame 18 forms a cavity of the liquid cooling plate 3, and the shunt bars divide the cooling cavity into a plurality of liquid cooling flow channels 19 which are sequentially connected in a head-tail mode. The two ends of the liquid cooling flow channel 19 are connected with the liquid inlet and the liquid outlet arranged on the two vertical frame sides of the frame 18. The liquid cooling flow channel 19 is a series flow channel, forms a long flow channel in the horizontal length direction, and is twice as long as a general flow channel. The surface of the liquid cooling flow channel 19 is provided with the heat dissipation fin, the heat dissipation fin connects the upper cover plate 16 and the lower cover plate 17, and the heat dissipation fin is used to increase the heat dissipation area and effectively improve the heat dissipation efficiency. The cooling liquid with high heat conduction coefficient and low corrosion, such as ethylene glycol aqueous solution, is selected in the liquid cooling flow channel 19, circulates in the liquid cooling flow channel 19, absorbs the heat generated by the battery module 1, and the heated cooling liquid is discharged through the liquid outlet, cooled by a cooling system and then recycled. Through liquid cooling, the working temperature of the battery module is effectively reduced, and the heat dissipation efficiency of the battery pack and the service life of the battery cell are improved.

[0044] Working principle of the high-capacity liquid-cooled energy storage battery pack in the utility model

[0045] The cooling liquid ethylene glycol aqueous solution is introduced into the liquid cooling channel 19 through the liquid inlet on the frame 18, circulates in the liquid cooling channel 19, absorbs the heat generated by the battery module 1, and is discharged through the liquid outlet on the frame 18, and is recycled after being cooled outside the battery pack.

[0046] The utility model discloses a cooling liquid ethylene glycol aqueous solution radiates heat, effectively reduces the working temperature of battery module 1, improves the heat dissipation efficiency of battery pack and the service life of electric core.

[0047] The above only is the preferred embodiment of the utility model and does not use for limiting the utility model, for the technical personnel of the field, the utility model can have various changes and changes. Any modification, equivalent replacement, improvement etc. that is made within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A high-capacity liquid-cooled energy storage battery pack, characterized in that, It includes a housing and a battery cell module, a flexible circuit board, and a liquid cooling plate inside the housing. The flexible circuit board is located on the top of the battery cell module, and the liquid cooling plate is located on the bottom of the battery cell module. The battery cell module contains lithium iron phosphate cells.

2. The high-capacity liquid-cooled energy storage battery pack according to claim 1, characterized in that, The box is a rectangular box, including a box top cover, a box bottom cover, and side panels arranged around the box. The side panels include horizontal side panels and vertical side panels. The horizontal side panels are arranged horizontally, and the vertical side panels are arranged vertically. The horizontal side panels and the vertical side panels are vertically connected.

3. The high-capacity liquid-cooled energy storage battery pack according to claim 2, characterized in that, The vertical side plate is provided with a plug-in interface, which includes a first plug-in interface and a second plug-in interface. The first plug-in interface is provided with a panel, and the panel is provided with a power connector and a communication connector. The second connector is equipped with a maintenance cover, a safety valve, and a fire sprinkler.

4. The high-capacity liquid-cooled energy storage battery pack according to claim 2, characterized in that, A sealing ring is provided between the top cover of the box and the flexible circuit board. The flexible circuit board is a rectangular plate made of FPC.

5. The high-capacity liquid-cooled energy storage battery pack according to claim 1, characterized in that, The battery cell module has a rectangular structure and includes a battery cell, a connector, and a battery management system. The number of battery cells is several, which are connected in series or parallel through the connector. The battery management system is set on the battery cell. The battery cell is a 628Ah capacity lithium iron phosphate cell.

6. The high-capacity liquid-cooled energy storage battery pack according to claim 5, characterized in that, The connector includes an end plate, a steel strip, and a flexible copper busbar. The end plate is vertically arranged on the four sides of the battery cell, and the steel strip is horizontally arranged on the top and bottom of the battery cell and is located outside the end plate. The flexible copper busbar is arranged on the surface of adjacent battery cells. Aerogel is provided between adjacent battery cells.

7. The high-capacity liquid-cooled energy storage battery pack according to claim 1, characterized in that, Thermally conductive gel is provided between the liquid cooling plate and the battery module.

8. The high-capacity liquid-cooled energy storage battery pack according to claim 1, characterized in that, The liquid cooling plate includes an upper cover plate, a lower cover plate, and a frame. The frame is disposed between the upper cover plate and the lower cover plate. The upper cover plate, the lower cover plate, and the frame are all rectangular plates, and the upper cover plate and the lower cover plate have the same size, but the upper cover plate is smaller than the frame.

9. The high-capacity liquid-cooled energy storage battery pack according to claim 8, characterized in that, The frame is provided with several diversion strips, liquid inlets and liquid outlets. The frame includes a vertical frame and a horizontal frame, which are vertically connected. The diversion strips are horizontally arranged inside the frame. The liquid inlets and liquid outlets are respectively located on the two vertical frame sides of the frame and are arranged opposite to each other.

10. The high-capacity liquid-cooled energy storage battery pack according to claim 8, characterized in that, The space enclosed by the upper cover plate, the lower cover plate, and the frame constitutes the cavity of the liquid cooling plate. The flow divider divides the cooling cavity into several liquid cooling channels connected end to end. The two ends of the liquid cooling channels are respectively connected to the liquid inlet and liquid outlet provided on the two vertical sides of the frame. The surface of the liquid cooling channels is provided with heat dissipation fins, which are connected to the upper cover plate and the lower cover plate. The liquid cooling channels are provided with coolant, which is an aqueous solution of ethylene glycol.

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