Battery module and energy storage equipment

Abstract

The invention discloses a battery module and energy storage equipment, the battery module comprises a box body and a plurality of single batteries which are arranged in the box body and are insulated from the box body, and the battery module is characterized in that the box body comprises an upper cover assembly, a lower cover assembly and two end covers; a fire fighting access is arranged in the upper cover assembly; a connecting channel is arranged between the explosion venting membrane of the top cover of each single battery and the thermal runaway flue gas emission channel; the lower cover assembly is internally provided with a heat exchange medium circulation channel, and temperature control of each single battery is realized through a heat exchange medium flowing in the heat exchange medium circulation channel, so that uniformity of each single battery is ensured, and the probability of occurrence of a thermal runaway phenomenon is also reduced; meanwhile, when the single batteries are subjected to thermal runaway, a fire fighting medium can be injected into the single batteries subjected to thermal runaway by utilizing the fire fighting access, and the fire fighting medium can absorb and cool the thermal runaway flue gas released by the single batteries, so that the risk of thermal runaway is reduced, and the safety of the battery module is improved.

Description

Technical Field

[0001] This invention belongs to the field of batteries, specifically relating to a battery module and an energy storage device. Background Technology

[0002] Lithium-ion batteries have a wide range of applications. However, due to their principle and structural characteristics, repeated use can lead to the following problems caused by temperature fluctuations:

[0003] When used in environments with excessively low ambient temperatures, the viscosity of the electrolyte increases, hindering the movement of Li ions. The insertion and extraction of Li ions on the negative electrode surface disrupts the equilibrium, resulting in some Li ions depositing on the negative electrode surface and causing lithium plating, which in turn leads to a loss of battery capacity.

[0004] When a battery is exposed to excessively high temperatures, the electrolyte and active materials become highly reactive, leading to side reactions and electrolyte decomposition within the battery. This results in capacity loss and gas production, causing the battery to swell. If the accumulated heat is not effectively dissipated during continued operation, the temperature will rise further. When the temperature reaches its limit, the battery's thermal equilibrium will be disrupted, triggering a series of self-heating side reactions that produce large amounts of flammable gas, resulting in "thermal runaway." Ultimately, this can lead to an internal fire, and in severe cases, an explosion, posing a threat to the user's safety.

[0005] Most existing electric two-wheelers, electric vehicles, and energy storage devices use multiple lithium-ion batteries connected in series and parallel to form battery modules. This makes the impact of temperature on the battery modules even more pronounced. In particular, when the temperature of a single cell in the battery module is too high or too low, the capacity difference of that single cell will affect the uniformity of the entire battery module. Most importantly, when a single cell experiences thermal runaway due to excessive temperature, it will affect the other cells in the battery module and even the external environment.

[0006] To address the impact of temperature on battery modules, current battery modules typically incorporate temperature control mechanisms to ensure uniformity while reducing the probability of thermal runaway. Alternatively, they may include fire suppression systems to promptly prevent subsequent adverse effects from thermal runaway.

[0007] However, existing battery modules all rely on individual temperature control mechanisms or fire suppression systems to ensure reliable operation. The former still carries the risk of thermal runaway, and if it occurs without effective handling, it can lead to safety accidents. While the latter can address thermal runaway promptly, the lack of temperature control over the battery module means that the uniformity of individual cells gradually deteriorates after a period of operation, resulting in a reduced cycle life and a relatively higher probability of thermal runaway. Summary of the Invention

[0008] In order to address the safety issues that existing battery modules that only employ temperature control may cause thermal runaway, and the issues that battery modules that only employ fire-fighting equipment will have reduced cycle life and a relatively high probability of thermal runaway due to the gradual deterioration of uniformity after a period of operation, the first aspect of this invention provides a battery module.

[0009] The battery module includes a housing and multiple individual batteries housed inside the housing and insulated from it. Its improvements are as follows:

[0010] The enclosure includes an upper cover assembly, a lower cover assembly, and two end caps;

[0011] A fire escape channel is provided inside the top cover assembly; a connecting channel is provided between the explosion relief membrane of each individual battery top cover and the fire escape channel. After the individual battery experiences thermal runaway and breaks through the explosion relief membrane, the fire-fighting medium is directly injected into the inner cavity of the individual battery that has experienced thermal runaway through the fire escape channel and the connecting channel.

[0012] The lower cover assembly is equipped with a heat exchange medium flow channel, through which the temperature of each individual battery cell is controlled.

[0013] This invention features a cleverly designed battery module housing. The upper cover assembly serves as a fire escape route, while the lower cover assembly forms a heat exchange medium flow channel. This allows the battery module to control the temperature of each individual cell during operation using the heat exchange medium, ensuring uniformity among cells and reducing the probability of thermal runaway. Furthermore, in the event of thermal runaway in a cell, the fire escape route allows for the injection of fire extinguishing media into the affected cell. This media absorbs and cools the released thermal runaway gases, further reducing the risk of thermal runaway and enhancing the overall safety of the battery module.

[0014] Preferably, in order to ensure that the volume of the battery module remains almost unchanged, and to ensure the positioning and insulation of each individual battery cell within the casing, an insulating top cover is snapped onto the top of each individual battery cell; each individual battery cell is insulated from the upper cover assembly by the insulating top cover, and the insulating top cover is provided with a terminal clearance hole for the protrusion of the individual battery cell's terminal post; the bottom of each individual battery cell is fixedly mounted to the lower cover assembly by an insulating fixing frame, and the bottom of each individual battery cell is insulated from the lower cover assembly.

[0015] Preferably, in order to reduce the processing cost of parts and facilitate the assembly of battery modules, multiple individual batteries located on the same straight line can share an insulating top cover and an insulating fixing frame.

[0016] Preferably, in order to facilitate installation and ensure the insulation between the individual battery and the top cover assembly, the connection channel includes a first connecting pipe and a second connecting pipe; the first connecting pipe is welded and fixed to the top cover assembly, the second connecting pipe is integrally formed on the insulating top cover, the projection of the second connecting pipe onto the top cover of the individual battery should cover the area of ​​the explosion relief membrane, the first connecting pipe is inserted into the second connecting pipe, and the gap between the first connecting pipe and the second connecting pipe is kept sealed from the outside.

[0017] Preferably, in order to ensure the sealing of the connecting tube assembly, an annular sealing ring is provided on the upper surface of the top cover of the single battery cell. The annular sealing ring is used to make close contact with the end of the first connecting tube located inside the second connecting tube.

[0018] Preferably, in order to facilitate the installation and cooperation of the first connecting pipe and the second connecting pipe, the portion of the first connecting pipe located inside the second connecting pipe is at least partially tapered.

[0019] Preferably, to facilitate the processing and assembly of the upper cover assembly and the lower cover assembly, the specific structures of the upper cover assembly and the lower cover assembly in this invention are as follows:

[0020] The aforementioned top cover assembly includes a first plate and a first quick-connect connector;

[0021] The first plate includes an integrally formed first horizontal plate and two first vertical plates. The first horizontal plate has an integrally formed thermal runaway flue gas emission channel, and the first horizontal plate has multiple through holes for connecting the first connecting pipe and the thermal runaway flue gas emission channel.

[0022] The two first vertical plates are used to splice with the lower cover assembly to form the two side walls of the box;

[0023] The first quick-connect fitting is installed on the first horizontal plate to serve as a connection between the fire escape route and external fire protection equipment.

[0024] Furthermore, the aforementioned lower cover assembly includes a second plate and a second quick-connect connector;

[0025] The second plate includes an integrally formed second horizontal plate and two second vertical plates. The second horizontal plate has an integrally formed heat exchange medium flow channel.

[0026] Two second vertical plates are used to splice with the top cover assembly to form the two side walls of the box;

[0027] There are two second quick-connect fittings, both installed on the second horizontal plate, used as the inlet and outlet of the heat exchange medium flow channel, respectively.

[0028] Preferably, in order to improve the integration of the battery module and reduce the influence of the external environment on the circuit part of the battery module, the present invention integrates the main control circuit board in one of the end covers. The specific structure is as follows: there are two end covers, and both are fixedly connected to the upper cover assembly and the lower cover assembly by screws. One of the two end covers has a receiving cavity between itself and the single battery cell. The main control circuit board is fixedly installed in the receiving cavity. The main control circuit board is provided with signal output terminals, and at least part of the signal output terminals extends out of the end cover.

[0029] Preferably, in order to simplify the circuit and signal transmission structure in the battery module, the above also includes an electrical signal acquisition and transmission board. The electrical signal acquisition and transmission board is laid between the top cover and the top cover assembly of all individual batteries. The main positive terminal and the main negative terminal of the battery module are led out from one side and connected to the main positive quick connector and the main negative quick connector provided on the end cover. The signal on the electrical signal acquisition and transmission board is output to the outside through the signal output terminal provided on the main control circuit board.

[0030] A second aspect of the present invention provides an energy storage device, comprising an energy storage cabinet, a temperature control device, a fire suppression device, and multiple battery modules as described in the first aspect. The energy storage cabinet includes a battery compartment and an equipment compartment. Multiple battery modules are installed in the battery compartment. The temperature control device and the fire suppression device are installed in the equipment compartment. The temperature control device is connected to a heat exchange medium flow channel of each battery module. The fire suppression device is connected to a fire escape channel of each battery module. This structural layout of the energy storage device not only ensures the energy density of the energy storage device but also ensures the cycle performance and safety of each battery module through the temperature control device and the fire suppression device.

[0031] Furthermore, the aforementioned fire-fighting device includes a fire-fighting medium tank, a first pipeline, and a second pipeline; one end of the first pipeline is connected to the outlet of the fire-fighting medium tank, and the other end of the first pipeline is connected to the fire passage entrance of each battery module; one end of the second pipeline is connected to the inlet of the fire-fighting medium tank, and the other end of the second pipeline is connected to the fire passage outlet of each battery module; a solenoid valve and a water pump are sequentially installed on the first pipeline along the flow direction of the fire-fighting medium; a first adsorption tank, a water pump, and a solenoid valve are sequentially installed on the second pipeline along the flow direction of the fire-fighting medium.

[0032] Furthermore, a first adsorption tank is installed on the aforementioned first pipeline, located between the fire escape entrance of the water pump and the battery module.

[0033] Furthermore, an exhaust valve is also installed on the second pipeline. The inlet end of the exhaust valve is connected between the solenoid valve and the inlet of the fire-fighting medium tank, and the outlet end of the exhaust valve is connected to the second adsorption tank.

[0034] Furthermore, the aforementioned temperature control device includes a liquid cooler, a third pipeline, and a fourth pipeline; one end of the third pipeline is connected to the outlet of the liquid cooler, and the other end of the third pipeline is connected to the inlet of the heat exchange medium flow channel of each battery module; one end of the fourth pipeline is connected to the inlet of the liquid cooler, and the other end of the fourth pipeline is connected to the outlet of the heat exchange medium flow channel of each battery module.

[0035] The beneficial effects of this invention are:

[0036] 1. This invention ingeniously utilizes the upper cover assembly of the battery module's casing as a fire escape route and the lower cover assembly as a heat exchange route. This not only allows for temperature control of each individual cell during operation, ensuring uniformity among cells and reducing the probability of thermal runaway, but also enables the injection of fire extinguishing agents into the affected cell via the fire escape route. These agents absorb and cool the released thermal runaway fumes, further reducing the risk of thermal runaway and thus enhancing the safety of the battery module.

[0037] 2. In this invention, the insulation and positioning of each individual battery cell within the housing are achieved by using an insulating top cover and an insulating fixing frame. Furthermore, the side walls of the insulating top covers of adjacent individual batteries are in contact with each other, creating gaps between each individual battery cell that serve as heat dissipation channels. Compared to the method of setting multiple partitions and insulating sealant within the housing to achieve insulation and positioning of individual batteries, the processing and assembly of parts are relatively simple, the manufacturing cost is relatively low, and the heat dissipation is superior.

[0038] 3. In this invention, multiple individual batteries share an insulating top cover and an insulating fixing frame to achieve positioning and insulation, which can further reduce costs.

[0039] 4. In this invention, the connecting channel is constructed by welding a first connecting pipe fixed to the top cover assembly and a second connecting pipe integrally formed on the insulating top cover, which can save the size of the battery module in the height direction, facilitate the assembly and disassembly of parts, and also improve the insulation of the top cover assembly.

[0040] 5. In this invention, an annular sealing ring is provided on the upper surface of the top cover of the single battery cell. The annular sealing ring is used to make close contact with the end of the first connecting pipe located inside the second connecting pipe. This cooperation method avoids the leakage of thermal runaway flue gas from the gap between the first connecting pipe and the second connecting pipe, and further ensures the airtightness of the connection channel.

[0041] 6. In order to facilitate the installation and cooperation of the first connecting pipe and the second connecting pipe, the portion of the first connecting pipe located inside the second connecting pipe is at least partially tapered.

[0042] 7. In this invention, the upper cover assembly and the lower cover assembly are connected by splicing. At the same time, the main body of the upper cover assembly and the lower cover assembly are made by one-piece molding process, which reduces the processing and assembly links and difficulties, and improves the finished product efficiency of parts and battery modules.

[0043] 8. By integrating the main control circuit board into the end cover, the integration of the battery module is improved, and the influence of the external environment on the circuit part of the battery module is reduced.

[0044] 9. In order to simplify the circuit and signal transmission structure in the battery module, the battery module adopts an electrical signal acquisition and transmission board to acquire and transmit the signals of each individual battery cell, thus avoiding the structural complexity and inconvenience of assembly and maintenance caused by setting up multiple cables.

[0045] 10. The energy storage cabinet of the energy storage device of the present invention is divided into a battery compartment and an equipment compartment. The battery compartment integrates multiple battery modules, and the equipment compartment integrates a temperature control device and a fire-fighting device. The structural layout of the energy storage device not only ensures the energy density of the energy storage device, but also ensures the cycle performance and safety of each battery module by utilizing the temperature control device and the fire-fighting device.

[0046] 11. The fire-fighting device of the present invention includes a fire-fighting medium tank, a first pipeline and a second pipeline. The fire-fighting medium can directly act on the inner cavity of the thermal runaway single cell, reducing the impact of the thermal runaway single cell on adjacent single cells and improving the safety of the energy storage device. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the three-dimensional structure of the battery module;

[0048] Figure 2 A schematic diagram of the battery module structure after removing the top cover assembly and end cover;

[0049] Figure 3 A cross-sectional view of the battery module from a first-person perspective;

[0050] Figure 4 This is a structural schematic diagram of the first plate.

[0051] Figure 5 for Figure 4 A sectional view;

[0052] Figure 6 This is a structural schematic diagram of the second plate.

[0053] Figure 7 for Figure 6 A sectional view;

[0054] Figure 8 This is a cross-sectional view of the battery module from a second perspective.

[0055] Figure 9 for Figure 8 A magnified view of a portion of the image;

[0056] Figure 10 A first-view structural diagram of the insulating top cover;

[0057] Figure 11 This is a schematic diagram of the insulating top cover from a second perspective.

[0058] Figure 12 This is a schematic diagram of the insulating fixing frame.

[0059] Figure 13 This is a three-dimensional schematic diagram of an energy storage device;

[0060] Figure 14 This is the front view of the energy storage device;

[0061] Figure 15 This is a schematic diagram of a fire-fighting system.

[0062] Figure 16 This is a schematic diagram of a temperature control device.

[0063] The attached figures are labeled as follows:

[0064] 1-Box body, 2-End cover, 3-Upper cover assembly, 4-Lower cover assembly, 5-Single battery, 6-Fire escape route, 7-Connecting passage, 8-First plate, 9-First quick connector, 10-First horizontal plate, 11-First vertical plate, 12-Heat exchange medium flow passage, 13-Second plate, 14-Second quick connector, 15-Second horizontal plate, 16-Second vertical plate, 17-Weight reduction groove, 18-Accommodation cavity, 19-Main control circuit board, 20-Signal output terminal, 21-Insulating top cover, 22-Pole post clearance hole, 23-Insulating fixing frame, 24-First connecting pipe, 25-Second connecting pipe, 26-Annular sealing ring, 27-Electrical signal acquisition and transmission board, 28-Main positive terminal, 29-Main negative terminal, 30-Main positive quick connector, 31-Main negative quick connector, 32-Through hole.

[0065] 100-Energy storage equipment, 101-Energy storage cabinet, 102-Temperature control device, 1021-Liquid chiller, 1022-Third pipeline, 1023-Fourth pipeline, 103-Fire-fighting device, 1031-Fire-fighting medium tank, 1032-First pipeline, 1033-Second pipeline, 1034-Solenoid valve, 1035-Water pump, 1036-First adsorption tank, 1037-Second adsorption tank, 1038-Exhaust valve, 1039-Third adsorption tank, 104-Battery module. Detailed Implementation

[0066] The technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments, and not all of the embodiments. Based on the following embodiments, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this invention.

[0067] It should also be noted that the terms "upper," "lower," "inner," and "outer," etc., used in this document to indicate the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the purpose of simplifying the description and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the technical solution. Furthermore, the terms "first," "second," or "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0068] Unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" in this invention should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; similarly, they can refer to mechanical connections, electrical connections, or direct connections, or indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0069] The battery module of this invention mainly includes a housing and multiple individual battery cells. The individual battery cells can be connected in series, in parallel, or in a mixed series-parallel connection, and can be adjusted as needed. In this embodiment, all individual battery cells are connected in series.

[0070] In this embodiment, the single battery cell uses a commercially available prismatic lithium-ion battery. The number of single batteries can be increased or decreased according to the specifications required for the battery module.

[0071] like Figures 1 to 3 As shown, in this embodiment, the housing 1 includes an end cap 2, an upper cover assembly 3, and a lower cover assembly 4;

[0072] Two end caps 2, an upper cover assembly 3, and a lower cover assembly 4 are sealed together to form a housing 1. Multiple individual batteries 5 are placed inside the housing 1, and each individual battery 5 needs to be kept insulated from the housing 1.

[0073] In this embodiment, a fire escape channel 6 is provided inside the top cover assembly 3; a connecting channel 7 is provided between the explosion relief membrane of the top cover of each individual battery 5 and the fire escape channel 6. After the individual battery undergoes thermal runaway and breaks through the explosion relief membrane, the fire-fighting medium is directly injected into the inner cavity of the individual battery that has undergone thermal runaway through the fire escape channel and the connecting channel.

[0074] Specifically, such as Figure 1 As shown, in this embodiment, the upper cover assembly 3 includes a first plate 8 and a first quick connector 9; in order to ensure the strength and temperature resistance of the first plate 8, the first plate 8 is made of metal material. Considering cost and weight, in this embodiment, the first plate 8 is made of aluminum material.

[0075] like Figure 4 , Figure 5 as well as Figure 8 As shown, the first plate 8 includes an integrally formed first horizontal plate 10 and two first vertical plates 11. The first horizontal plate 10 has an integrally formed fire passage 6 (usually formed by extrusion or casting process; in order to form a sealed fire passage, a blocking plate needs to be welded to each end of the extruded or cast first horizontal plate). The first horizontal plate 10 has multiple through holes 32 for connecting the connecting passage 7 and the fire passage 6. The two first vertical plates 11 are used to splice with the lower cover assembly 4 to form the two side walls of the box body 1. The first quick-connect connector 9 is installed on the first horizontal plate 10 as a connecting piece for connecting the fire passage 6 with external fire-fighting equipment.

[0076] like Figure 6 , Figure 7 as well as Figure 8 As shown, a heat exchange medium flow channel 12 is provided inside the lower cover assembly 4. The temperature of each individual battery cell 5 is controlled by the heat exchange medium flowing within the heat exchange medium flow channel 12. Various heat exchange media can be selected, including air, liquid, or phase change material. Air has a poorer temperature control effect compared to liquid and phase change material. When used here, phase change material is more expensive than liquid and its temperature control effect is less stable. Therefore, in this embodiment, a liquid is preferred as the heat exchange medium. This liquid can be any one of water, mineral oil, or ethylene glycol.

[0077] In this embodiment, the specific structure of the lower cover assembly 4 is basically similar to that of the upper cover assembly 3, including a second plate 13 and a second quick-connect connector 14; the second plate 13 includes an integrally formed second horizontal plate 15 and two second vertical plates 16, and an integrally formed heat exchange medium flow channel 12 is formed in the second horizontal plate 15 (usually integrally formed by extrusion or casting process; in order to form a closed thermal runaway flue gas emission channel, a blocking plate needs to be welded to each end of the extruded or cast second horizontal plate); the two second vertical plates 16 are used to splice with the upper cover assembly 3 to form two side walls of the box 1; there are two second quick-connect connectors 14, both of which are installed on the second horizontal plate 15, and are used as the inlet and outlet of the heat exchange medium flow channel 12 respectively.

[0078] It should also be noted that: in this embodiment, the integrally formed heat exchange medium flow channel 12 is S-shaped, which can improve the heat exchange effect. At the same time, in this embodiment, the first vertical plate 11 and the second vertical plate 16 are connected vertically to form the side wall of the housing 1 by means of concave-convex fitting and screw fastening, which makes assembly more convenient. Furthermore, weight reduction grooves 17 can also be provided in the first vertical plate 11 and / or the second vertical plate 16 to reduce the weight of the battery module.

[0079] In some other embodiments, the first plate 8 of the upper cover assembly 3 and the second plate 13 of the lower cover assembly 4 can also be constructed by welding multiple sheet metal parts together. However, this method is relatively complex to manufacture, and it is difficult to guarantee the processing efficiency and performance of the parts.

[0080] In this embodiment, as Figure 1 and Figure 2 As shown, there are two end caps 2, both of which are fixedly connected to the upper cover assembly 3 and the lower cover assembly 4 by screws. To ensure good sealing and insulation, a sealing insulating gasket is provided between the end cap 2 and the upper cover assembly 3 and the lower cover assembly 4. One of the two end caps 2 has a receiving cavity 18 between itself and the single battery cell 5. The main control circuit board 19 is provided with a signal output terminal 20, at least a portion of which extends out of the end cap 2. The main control circuit board 19 is located in the end cap 2, which not only improves the integration of the battery module, but also reduces the influence of the external environment on the circuit part of the battery module.

[0081] In addition, such as Figure 3 , Figure 9 , Figure 10 , Figure 11 as well as Figure 12As shown in the figure, each individual battery 5 in this invention is fitted with an insulating top cover 21. The individual battery is kept insulated from the upper cover assembly 3 by the insulating top cover 21. The insulating top cover 21 is made of non-metallic insulating material, such as ABS or nylon. The insulating top cover 21 includes a square plate and side walls extending downward around the square plate. In order to avoid the terminals on the individual battery, the insulating top cover 21 is provided with terminal avoidance holes 22 for the terminals of the individual battery 5 to protrude. The use of the insulating top cover 21 not only keeps the individual battery 5 insulated from the upper cover assembly 3, but also keeps the individual batteries 5 located on both sides of the box 1 insulated from the side walls of the box, and also allows two adjacent individual batteries 5 connected in series to be insulated from each other.

[0082] Each individual battery cell 5 is fixedly mounted to the lower cover assembly 4 at its bottom via an insulating fixing frame 23, and the bottom of each individual battery cell 5 is insulated from the lower cover assembly 4. The insulating fixing frame 23 includes a rectangular frame adapted to the shape of the individual battery cell 5, and two lugs for connecting to the lower cover assembly are provided on the side wall of the rectangular frame. The insulation between the bottom of the individual battery cell 5 and the lower cover assembly 4 can be achieved by adding a thin insulating pad or by applying an insulating layer to the lower cover assembly.

[0083] To further reduce the manufacturing cost and assembly frequency of the insulating top cover 21 and the insulating fixing frame 23, this embodiment optimizes the structure. Multiple individual cells 5 can also share an insulating top cover 21 and an insulating fixing frame 23. In this embodiment, two series-connected individual cells located on the same straight line share an insulating top cover and an insulating fixing frame.

[0084] In some other embodiments, the positioning and insulation of individual cells can be achieved by adding a separator and insulating sealant inside the box. However, this method requires the separator to be set on the upper or lower cover assembly, and also requires a process of injecting insulating sealant, which makes the manufacturing of the entire battery module more troublesome and the structure more complex.

[0085] like Figure 9 As shown, in this embodiment, the connecting channel 7 is divided into two parts, including a first connecting pipe 24 and a second connecting pipe 25. The first connecting pipe 24 is sealed and fixed to the upper cover assembly 3 by welding, and the orthographic projection of the first connecting pipe 24 on the upper cover assembly 3 needs to cover the through hole 32 opened on the first horizontal plate 10. The second connecting pipe 25 is integrally formed on the insulating top cover 21, and the orthographic projection of the second connecting pipe 25 on the top cover of the single battery needs to cover the area of ​​the explosion relief membrane. The first connecting pipe 24 is inserted into the second connecting pipe 25, and the gap between the first connecting pipe 24 and the second connecting pipe 25 is kept sealed from the outside.

[0086] The insertion method of the first connecting pipe 24 and the second connecting pipe 25 makes it easy to complete the assembly of the connecting channel 7 and the connection with the fire channel 6 during the assembly process of the box. The assembly process is simple, and the second connecting pipe 25 is integrally formed on the insulating top cover 21, which means that the second connecting pipe 25 also has good insulation performance.

[0087] In some other embodiments, a tube can be used, with its two ends welded to the top cover assembly and the top cover of the individual battery cell to form a connecting channel, but this method is relatively difficult to process.

[0088] In this embodiment, as Figure 9 As shown, an annular sealing ring 26 is provided on the upper surface of the top cover of the single battery cell 5. The upper surface of the annular sealing ring 26 is used for tight contact with the end of the first connecting pipe 24 inside the second connecting pipe 25 (or this contact surface can be designed as a labyrinth-like sealing structure with concave and convex fits), which can prevent the leakage of thermal runaway smoke and ensure the airtightness of the communication channel 7. In some other embodiments, a sealing ring can also be added at the gap between the first connecting pipe 24 and the second connecting pipe 25, but this setting will make the insertion process of the two less smooth.

[0089] In this embodiment, in order to make the insertion and engagement of the first connecting pipe 24 and the second connecting pipe 25 smoother, the portion of the first connecting pipe 24 located inside the second connecting pipe 25 is at least partially tapered.

[0090] like Figure 2 As shown, in this embodiment, a signal acquisition and transmission board 27 replaces traditional cables on the battery module. The signal acquisition and transmission board 27 is laid between the insulating top cover 21 and the top cover assembly 3 of all individual batteries 5. The main positive terminal 28 and the main negative terminal 29 of the battery module are led out from one side and connected to the main positive quick connector 30 and the main negative quick connector 31 provided on the end cover 2. The signal on the signal acquisition and transmission board 27 is output to the outside through the signal output terminal 20 provided on the main control circuit board 19. In this embodiment, the signal acquisition and transmission board 27 is used to acquire and transmit the signals of each individual battery, avoiding the structural complexity and inconvenience of assembly and maintenance caused by setting multiple cables. At the same time, the main positive and main negative terminals of the battery module are led out from the same end cover, which also simplifies the wiring of external devices.

[0091] The battery module provided in this embodiment can be set up as a single charging and discharging device, or multiple modules can be set up and connected in series or parallel to form a large energy storage device.

[0092] like Figure 14 and Figure 15As shown, the energy storage device 100 includes an energy storage cabinet 101, a temperature control device 102, a fire-fighting device 103, and multiple battery modules 104 as described above.

[0093] The energy storage cabinet 101 has a battery compartment and an equipment compartment; multiple battery modules 104 are installed in the battery compartment; a temperature control device 102 and a fire-fighting device 103 are installed in the equipment compartment;

[0094] The fire-fighting device 103 includes: a first pipeline 1032, one end of which is connected to the outlet of the fire-fighting medium tank 1031, and the other end of which is connected to the fire passage entrance of each battery module; a second pipeline 1033, one end of which is connected to the inlet of the fire-fighting medium tank 1031, and the other end of which is connected to the fire passage outlet of each battery module; a water pump 1035 is sequentially arranged on the first pipeline 1032 along the flow direction of the fire-fighting medium; and a first adsorption tank 1036, a water pump 1035, and a solenoid valve 1034 are sequentially arranged on the second pipeline 1033 along the flow direction of the fire-fighting medium.

[0095] It should be noted that when a lithium-ion battery experiences thermal runaway, a series of chemical reactions occur internally, releasing a large amount of heat and gas. The exhaust gas from the thermal runaway mainly includes the following components: vaporized electrolyte, CO2, CO, H2, and C. x H y C x H y O z C x H y The electrolyte contains substances such as F, POF3, and HF. The vaporized electrolyte not only reacts with the positive or negative electrode plates inside the battery, but also undergoes a series of decomposition reactions, which in turn continue to produce a large amount of harmful gases.

[0096] When the temperature of any single cell A in a battery module of an energy storage device reaches 120°C, the fire suppression system starts to work. The fire suppression medium in the fire suppression medium tank is transported from the first pipeline to the fire suppression channel of the battery module's top cover assembly (at this time, the explosion relief membrane on the single cell A has not ruptured). Then, it flows back to the fire suppression medium tank through the second pipeline. At this time, the fire suppression medium circulates in the fire suppression medium tank, the first pipeline, the fire suppression channel, and the second pipeline. The flow of the fire suppression medium will have a certain cooling effect on the battery module.

[0097] When the internal pressure of cell A continues to increase, causing the explosion relief membrane to rupture, the thermal runaway flue gas in cell A initially enters the fire escape. The fire-fighting medium cools the vaporized electrolyte carried in the thermal runaway flue gas into a liquid state and flows into the second pipeline along with the fire-fighting medium. Then, when the fire-fighting medium passes through the first adsorption tank of the second pipeline, it adsorbs the harmful gases in the fire-fighting medium. After being purified and adsorbed, the fire-fighting medium flows back into the fire-fighting medium tank.

[0098] After the thermal runaway smoke from cell A has been released for a period of time, the pressure inside cell A decreases, and then the fire-fighting medium flows into the cavity of cell A to directly cool the inside of cell A, thereby further reducing the probability of thermal runaway propagation and improving safety.

[0099] In this embodiment, to treat the CO2 and CO in the thermal runaway flue gas, the fire-fighting medium can be an alkaline solution or an active liquid; the alkaline solution chemically absorbs carbon monoxide. Commonly used alkaline solutions include sodium hydroxide, potassium hydroxide, and sodium carbonate. Active liquids utilize liquids with high absorption capacity to absorb carbon monoxide. Common active liquids include N-methyldiacetamide (NMP), nitrile butyronitrile, and peptide solutions.

[0100] The adsorption medium filled in the first adsorption tank 1036 can adsorb carbon in the thermal runaway flue gas. x H y C x H y O z C x H y F, POF3 and HF are adsorbed.

[0101] Preferably, to prevent a small amount of thermal runaway flue gas from entering the first pipeline 1032, the fire-fighting device further includes a second adsorption tank 1037, which is located between the water pump 1035 and the fire escape inlet of the battery module 104. The purpose of the second adsorption tank 1037 is to adsorb the small amount of thermal runaway flue gas entering the first pipeline 1032, and the second adsorption tank 1037 uses the same adsorption medium as the first adsorption tank 1036.

[0102] Preferably, an exhaust valve 1038 is also provided on the second pipeline 1033. The inlet end of the exhaust valve 1038 is connected between the solenoid valve 1034 and the inlet of the fire medium tank 1031. The outlet end of the exhaust valve 1038 is connected to a third adsorption tank 1039. The purpose of the third adsorption tank 1039 is to completely adsorb the harmful gases that the first adsorption tank failed to adsorb completely, so as to avoid the harmful gases discharged from the exhaust valve from polluting the external environment.

[0103] The temperature control device 102 includes a liquid cooler 1021, a third pipe 1022, and a fourth pipe 1023; one end of the third pipe 1022 is connected to the outlet of the liquid cooler 1021, and the other end of the third pipe 1022 is connected to the inlet of the heat exchange medium flow channel of each battery module; one end of the fourth pipe 1023 is connected to the inlet of the liquid cooler 1021, and the other end of the fourth pipe 1023 is connected to the outlet of the heat exchange medium flow channel 12 of each battery module.

Claims

1. A battery module, comprising a housing and a plurality of individual batteries disposed within the housing and insulated from the housing, characterized in that: The enclosure includes an upper cover assembly, a lower cover assembly, and two end caps; A fire escape channel is provided inside the top cover assembly; a connecting channel is provided between the explosion relief membrane of each individual battery top cover and the fire escape channel. After the individual battery experiences thermal runaway and breaks through the explosion relief membrane, the fire-fighting medium is directly injected into the inner cavity of the individual battery that has experienced thermal runaway through the fire escape channel and the connecting channel. The lower cover assembly is equipped with a heat exchange medium flow channel, through which the temperature of each individual battery cell is controlled.

2. The battery module according to claim 1, characterized in that: An insulating top cover is snapped onto the top of each individual cell; each individual cell is insulated from the top cover assembly by the insulating top cover, and the insulating top cover is provided with a terminal clearance hole for the terminal of the individual cell to protrude. Each individual cell is fixedly mounted to the lower cover assembly at its bottom by an insulating frame, and the bottom of each individual cell is kept insulated from the lower cover assembly.

3. The battery module according to claim 2, characterized in that: Multiple individual cells located on the same straight line share an insulating top cover and an insulating fixing frame.

4. The battery module according to any one of claims 1 to 3, characterized in that: The connection channel includes a first connecting pipe and a second connecting pipe; the first connecting pipe is welded and fixed to the top cover assembly, and the second connecting pipe is integrally formed on the insulating top cover. The projection of the second connecting pipe onto the top cover of the individual battery cell should cover the area of ​​the explosion relief membrane. The first connecting pipe is inserted into the second connecting pipe, and the gap between the first connecting pipe and the second connecting pipe is kept sealed from the outside.

5. The battery module according to claim 4, characterized in that: An annular sealing ring is provided on the upper surface of the top cover of the single battery cell. The annular sealing ring is used to make close contact with the end of the first connecting tube located inside the second connecting tube.

6. The battery module according to claim 4, characterized in that: The portion of the first connecting pipe located inside the second connecting pipe is at least partially tapered.

7. The battery module according to claim 1, characterized in that: The top cover assembly includes a first plate and a first quick-connect connector; The first plate includes an integrally formed first horizontal plate and two first vertical plates. The first horizontal plate has an integrally formed fire escape channel, and the first horizontal plate has multiple through holes for connecting the first connecting pipe and the fire escape channel. The two first vertical plates are used to splice with the lower cover assembly to form the two side walls of the box; The first quick-connect fitting is installed on the first horizontal plate to serve as a connection between the fire escape route and external fire protection equipment.

8. The battery module according to claim 1, characterized in that: The lower cover assembly includes a second plate and a second quick-connect connector; The second plate includes an integrally formed second horizontal plate and two second vertical plates. The second horizontal plate has an integrally formed heat exchange medium flow channel. Two second vertical plates are used to splice with the top cover assembly to form the two side walls of the box; There are two second quick-connect fittings, both installed on the second horizontal plate, used as the inlet and outlet of the heat exchange medium flow channel, respectively.

9. The battery module according to claim 1, characterized in that: There are two end caps, both of which are fixedly connected to the upper cover assembly and the lower cover assembly by screws. One of the two end caps has a receiving cavity between itself and the single battery cell. A main control circuit board is fixedly installed in the receiving cavity. A signal output terminal is provided on the main control circuit board, and at least a portion of the signal output terminal extends out of the end cap.

10. The battery module according to claim 9, characterized in that: It also includes an electrical signal acquisition and transmission board, which is laid between the top cover and the upper cover assembly of all individual batteries. The main positive terminal and the main negative terminal of the battery module are led out from one side and connected to the main positive quick connector and the main negative quick connector set on the end cover. The signal on the electrical signal acquisition and transmission board is output to the outside through the signal output terminal set on the main control circuit board.

11. An energy storage device, characterized in that: It includes an energy storage cabinet, a temperature control device, a fire-fighting device, and multiple battery modules as described in any one of claims 1 to 10; the energy storage cabinet has a battery compartment and an equipment compartment; multiple battery modules are installed in the battery compartment; the temperature control device and the fire-fighting device are installed in the equipment compartment; the temperature control device is connected to the heat exchange medium flow channel of each battery module; the fire-fighting device is connected to the fire channel of each battery module.

12. An energy storage device according to claim 11, characterized in that: The fire-fighting equipment includes a fire-fighting medium tank, a first pipeline, and a second pipeline; One end of the first pipeline is connected to the outlet of the fire-fighting medium tank, and the other end of the first pipeline is connected to the fire escape entrance of each battery module; one end of the second pipeline is connected to the inlet of the fire-fighting medium tank, and the other end of the second pipeline is connected to the fire escape exit of each battery module. The first pipeline is equipped with a solenoid valve and a water pump in sequence along the direction of fire-fighting medium flow; The second pipeline is equipped with a first adsorption tank, a water pump, and a solenoid valve in sequence along the direction of fire-fighting medium flow.

13. An energy storage device according to claim 12, characterized in that: A first adsorption tank is installed on the first pipeline and between the fire access entrance of the water pump and the battery module.

14. An energy storage device according to claim 12, characterized in that: The second pipeline is also equipped with an exhaust valve. The inlet end of the exhaust valve is connected between the solenoid valve and the inlet of the fire-fighting medium tank, and the outlet end of the exhaust valve is connected to the second adsorption tank.

15. An energy storage device according to claim 11, characterized in that: The temperature control device includes a liquid cooler, a third pipeline, and a fourth pipeline; one end of the third pipeline is connected to the outlet of the liquid cooler, and the other end of the third pipeline is connected to the inlet of the heat exchange medium flow channel of each battery module. One end of the fourth pipeline is connected to the inlet of the liquid cooler, and the other end of the fourth pipeline is connected to the outlet of the heat exchange medium flow channel of each battery module.

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