Battery pack and vehicle

Abstract

The invention discloses a battery pack and a vehicle, and belongs to the technical field of vehicles. According to the battery pack provided by the invention, when any battery cell in the battery module is subjected to thermal runaway, the anti-explosion valve corresponding to the battery cell is opened, gas is sprayed out through the anti-explosion valve and the fire extinguishing hole corresponding to the anti-explosion valve, the coating film is melted by the temperature generated by the gas, and a fire extinguishing agent in the coating film flows into the battery cell through the anti-explosion valve and the fire extinguishing hole corresponding to the anti-explosion valve; therefore, automatic fire extinguishing is realized.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a battery pack and a vehicle. Background Art

[0002] Lithium batteries are widely used in new energy vehicles due to their high energy density, long cycle life, stable charge and discharge efficiency, etc. However, when a single cell fails during use, causing the temperature inside the lithium battery to rise, if it is not suppressed in time, it will cause heat spread in the battery pack, and eventually lead to uncontrollable heat diffusion, resulting in fire or even explosion. Summary of the invention

[0003] The embodiment of the present application provides a battery pack and a vehicle, which can automatically extinguish fire and suppress heat spread when the battery has thermal runaway. The technical solution is as follows:

[0004] On the one hand, an embodiment of the present application provides a battery pack, the battery pack comprising: a shell, and a battery module, a bracket cover plate, a mica plate, a coating film and a fire extinguishing agent located in the shell;

[0005] The support cover is located above the battery module and has a preset angle of inclination relative to the bottom surface of the shell, and the mica board is located above the support cover;

[0006] The battery module includes a plurality of battery cells;

[0007] A plurality of fire extinguishing holes are provided on the support cover plate, each of which corresponds to an explosion-proof valve on the battery cell;

[0008] The coating film is fixed on the bracket cover, and the fire extinguishing agent is contained in the coating film;

[0009] Among them, when thermal runaway occurs in any battery cell in the battery module, the explosion-proof valve corresponding to the battery cell opens, and gas is ejected through the explosion-proof valve and the fire extinguishing hole corresponding to the explosion-proof valve. The temperature generated by the gas melts the covering film, and the fire extinguishing agent in the covering film flows into the battery cell through the explosion-proof valve and the fire extinguishing hole corresponding to the explosion-proof valve.

[0010] In a possible implementation, the coating film includes a plurality of partition spaces, and the plurality of partition spaces are respectively located on both sides of the continuous channel and are both connected to the continuous channel;

[0011] The fire extinguishing agent is contained in each partition space.

[0012] In another possible implementation, the fire extinguishing agent includes at least one of the following components: heptafluoropropane, perfluorohexanone, trimethyl phosphate, 2-2,2,2-trifluoroethoxy-1,3,2-dioxaphospholane-2-oxide, 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane, methyl perfluorobutyl ether, tris(2,2,2-trifluoroethyl)phosphite, 1,2-bis(maleimide)ethane, 1,2-phenylene-bis-maleimide and 4,4'-bismaleimidodiphenylmethane.

[0013] In another possible implementation, the fire extinguishing agent includes a main fire extinguishing agent and an auxiliary fire extinguishing agent;

[0014] The main fire extinguishing agent includes at least one of 2-2,2,2-trifluoroethoxy-1,3,2-dioxaphospholane-2-oxide, 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane, tris(2,2,2 trifluoroethyl)phosphite, trimethyl phosphate, perfluorohexanone and heptafluoropropane;

[0015] The auxiliary fire extinguishing agent includes at least one of methyl perfluorobutyl ether, 1,2-bis(maleimide)ethane, 1,2-phenylene-bis-maleimide and 4,4'-bismaleimidodiphenylmethane.

[0016] In another possible implementation, the mass ratio of the main fire extinguishing agent to the auxiliary fire extinguishing agent is 9:1 to 5:5.

[0017] In another possible implementation, the main fire extinguishing agent includes a first main fire extinguishing agent and a second main fire extinguishing agent;

[0018] The mass ratio of the first main fire extinguishing agent, the second main fire extinguishing agent and the auxiliary fire extinguishing agent is 8:1:1 to 1:1:1.

[0019] In another possible implementation, the accumulation amount of the fire extinguishing agent in the coating film is 0.2 g / cm 2 ~0.5g / cm 2 .

[0020] In another possible implementation, the coating film includes at least one of polyethylene, polypropylene, chitosan and urea-formaldehyde polymer.

[0021] In another possible implementation, the coating film has a thickness of 20 μm to 50 μm.

[0022] On the other hand, an embodiment of the present application provides a vehicle, comprising a battery pack as described above.

[0023] An embodiment of the present application provides a battery pack. When thermal runaway occurs in any battery cell in a battery module, the explosion-proof valve corresponding to the battery cell opens, and gas is ejected through the explosion-proof valve and the fire extinguishing hole corresponding to the explosion-proof valve. The temperature generated by the gas melts the coating film, and the fire extinguishing agent in the coating film flows into the battery cell through the explosion-proof valve and the fire extinguishing hole corresponding to the explosion-proof valve, thereby achieving automatic fire extinguishing.

[0024] It is to be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic diagram of a battery pack provided in an embodiment of the present application;

[0026] Figure 2 This is a schematic diagram showing the flow direction of a fire extinguishing agent after a single battery cell thermal runaway provided in an embodiment of the present application.

[0027] The reference numerals represent:

[0028] 10-shell, 11-battery module, 12-bracket cover, 13-mica board, 14-coating film, 15-fire extinguishing agent, 16-battery cell, 17-fire extinguishing hole, 18-explosion-proof valve, 141-partition space, 142-continuous channel. DETAILED DESCRIPTION

[0029] In order to make the technical solutions and advantages of the present application clearer, the implementation methods of the present application are described in further detail below.

[0030] The terms "first", "second", "third" and "fourth" in the specification and claims of this application and the drawings are used to distinguish different objects rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or devices is not limited to the listed steps or devices, but optionally includes steps or devices that are not listed, or optionally includes other steps or devices inherent to these processes, methods, products or devices.

[0031] For new energy vehicles, when a single cell of a lithium battery fails during use, causing the temperature inside the lithium battery to rise, if it is not suppressed in time, it will cause heat spread in the battery pack, and eventually the heat spread cannot be suppressed, resulting in fire or even explosion. Therefore, it is crucial to extinguish the fire and suppress the heat spread in the early stage after the thermal runaway of the cell, which is very important for the safety of the battery system.

[0032] However, if water is used to extinguish the fire, leakage and electric shock may occur, threatening the lives of firefighters. Using dry powder fire extinguishers requires manual observation and prevention work, and is limited by the large size of dry powder fire extinguishers and cannot be placed due to vehicle space constraints.

[0033] To solve the above problems, the present application provides a battery pack. Figure 1 The battery pack includes: a housing 10, and a battery module 11, a bracket cover 12, a mica board 13, a coating film 14 and a fire extinguishing agent 15 located in the housing 10;

[0034] The support cover plate 12 is located above the battery module 11 and has a preset angle of inclination relative to the bottom surface of the housing 10 . The mica board 13 is located above the support cover plate 12 .

[0035] The battery module 11 includes a plurality of battery cells 16;

[0036] A plurality of fire extinguishing holes 17 are provided on the bracket cover plate 12, and each fire extinguishing hole 17 corresponds to an explosion-proof valve 18 on the battery cell 16;

[0037] The coating film 14 is fixed on the bracket cover 12, and the fire extinguishing agent 15 is contained in the coating film 14;

[0038] Among them, when any battery cell 16 in the battery module 11 experiences thermal runaway, the explosion-proof valve 18 corresponding to the battery cell 16 opens, and the gas is ejected through the explosion-proof valve 18 and the fire extinguishing hole 17 corresponding to the explosion-proof valve 18. The temperature generated by the gas melts the coating film 14, and the fire extinguishing agent 15 in the coating film 14 flows into the battery cell 16 through the explosion-proof valve 18 and the fire extinguishing hole 17 corresponding to the explosion-proof valve 18.

[0039] In an embodiment of the present application, the battery pack includes a shell 10, a battery module 11 is located in the shell 10, the battery module 11 includes a plurality of battery cells 16, each battery cell 16 is provided with an explosion-proof valve 18, when the internal pressure of the battery cell 16 is high and exceeds a preset pressure, the explosion-proof valve 18 will automatically open to release the internal gas, thereby reducing the pressure inside the battery cell 16 and preventing the battery cell 16 from bursting.

[0040] The housing 10 is used to accommodate the battery module 11, the bracket cover 12, the mica board 13, the coating film 14 and the fire extinguishing agent 15, and plays a protective and supporting role.

[0041] The material of the housing 10 can be set and changed as needed, and is not specifically limited thereto. For example, the housing 10 is made of a composite material, such as a carbon fiber reinforced composite material, or a metal material, such as steel or aluminum alloy.

[0042] The size of the housing 10 can also be set and changed as needed, and there is no specific limitation on this.

[0043] In a possible implementation, a plurality of fire extinguishing holes 17 are provided on the support cover 12, and each fire extinguishing hole 17 corresponds to the explosion-proof valve 18 on each battery cell 16, that is, the number of the fire extinguishing holes 17 is the same as the number of the battery cells 16. The battery module 11 includes 90 to 200 battery cells 16 according to different battery types, and accordingly, 90 to 200 fire extinguishing holes 17 are provided on the support cover 12. For example, the battery module 11 includes 90 battery cells 16, and an explosion-proof valve 18 is provided on each battery cell 16, then 90 fire extinguishing holes 17 are provided on the support cover 12, and the position of each fire extinguishing hole 17 corresponds to the position of the explosion-proof valve 18 on each battery cell 16.

[0044] Among them, the number of battery cells 16 can be 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, or 200, without specific limitation.

[0045] The shape of the fire extinguishing hole 17 can be set and changed as needed, and is not specifically limited in the embodiment of the present application. For example, the shape of the fire extinguishing hole 17 is circular, oval or square.

[0046] In addition, the size of the fire extinguishing hole 17 can also be set and changed as needed, and there is no specific limitation on this in the embodiment of the present application.

[0047] In a possible implementation, the bracket cover 12 has a preset angle of inclination. The size of the preset angle can be set and changed as needed, and is not specifically limited to this. For example, the preset angle is 3°, 4°, 5°, or 6°.

[0048] The support cover 12 is made of fireproof material, and the specific type of the fireproof material can be set and changed as needed, and there is no specific limitation on this.

[0049] The thickness of the bracket cover 12 can also be set and changed as needed, and is not specifically limited in the embodiment of the present application.

[0050] In the embodiment of the present application, the bracket cover 12 has a certain inclination angle, so that when the coating film 14 melts, the fire extinguishing agent 15 in the coating film 14 can automatically flow into the battery cell 16 through the explosion-proof valve 18 and the fire extinguishing hole 17 corresponding to the explosion-proof valve 18 under the action of gravity, thereby realizing automatic fire extinguishing.

[0051] In a possible implementation, the mica board 13 is located above the bracket cover 12 and below the upper cover inside the battery pack, and the coating film 14 is located between the mica board 13 and the bracket cover 12 .

[0052] The mica board 13 is a high temperature resistant plate-shaped material, which is made by bonding mica paper and organic silica gel water, heating and pressing. The mica board 13 is used as a fireproof material inside the battery to prevent the ejected gas from damaging the battery pack.

[0053] The thickness of the mica board 13 can be set and changed as needed, and is not specifically limited in the embodiment of the present application.

[0054] The present application sets a support cover plate 12 above the battery module 11, and opens a plurality of fire extinguishing holes 17 on the support cover plate 12, each fire extinguishing hole 17 corresponds to the explosion-proof valve 18 on each battery cell 16, and a coating film 14 is fixed on the support cover plate 12, and a fire extinguishing agent 15 is coated in the coating film 14. When any battery cell 16 has thermal runaway, the explosion-proof valve 18 corresponding to the battery cell 16 opens, and the gas is ejected through the explosion-proof valve 18 and the fire extinguishing hole 17 corresponding to the explosion-proof valve 18. The temperature generated by the gas melts the coating film 14, and the fire extinguishing agent 15 in the coating film 14 flows into the battery cell 16 through the explosion-proof valve 18 and the fire extinguishing hole 17 corresponding to the explosion-proof valve 18, thereby realizing automatic fire extinguishing.

[0055] In one possible implementation, see Figure 2 The coating film 14 includes a plurality of partition spaces 141, and the plurality of partition spaces 141 are respectively located on both sides of the continuous channel 142 and are all connected to the continuous channel 142;

[0056] Each partition space 141 contains a fire extinguishing agent 15 .

[0057] from Figure 2 It can be seen from the figure that: starting from the left side, when the second battery cell 16 has thermal runaway, high-temperature gas or flame is ejected through the explosion-proof valve 18 and the fire extinguishing hole 17 corresponding to the explosion-proof valve 18, and the high-temperature gas or flame melts the coating film 14, and the fire extinguishing agent 15 in the coating film 14 flows into the battery cell 16 through the explosion-proof valve 18 and the fire extinguishing hole 17 corresponding to the explosion-proof valve 18, thereby achieving the effect of fire extinguishing and flame retardant.

[0058] In this implementation, the covering film 14 may be hot-pressed by a covering film 14 hot-pressing device, thereby forming a plurality of partition spaces 141 .

[0059] The size of the partition space 141 can be set and changed as needed, and is not specifically limited in the embodiment of the present application.

[0060] In the embodiment of the present application, multiple partition spaces 141 are connected to the continuous channel 142, so that when the coating film 14 melts, the fire extinguishing agent 15 in each partition space 141 can flow into the battery cell 16 through the middle continuous channel 142, thereby extinguishing the fire in a short time and improving the fire extinguishing efficiency.

[0061] In a possible implementation, the coating film 14 includes at least one of polyethylene (PE), polypropylene (PP), chitosan, and urea-formaldehyde polymer.

[0062] In a possible implementation, the coating film 14 has a thickness of 20 μm to 50 μm.

[0063] In this implementation, the thickness of the coating film 14 can be 20 μm, 25 μm, 28 μm, 30 μm, 35 μm, 38 μm, 40 μm, 45 μm, 48 μm, or 50 μm, without specific limitation.

[0064] In a possible implementation, the temperature at which the coating film 14 is thermally decomposed is greater than 0°C.

[0065] In this implementation, the temperature at which the coating film 14 is thermally decomposed may be 1°C, 0°C, 0°C, 0°C, 0°C, and 0°C, and there is no specific limitation on this.

[0066] In a possible implementation, the method of fixing the coating film 14 on the support cover plate 12 can be set and changed as needed, and is not specifically limited to this. For example, the coating film 14 is fixed on the support cover plate 12 by gluing.

[0067] In a possible implementation, the battery pack further includes: at least one temperature sensor and a battery management system;

[0068] For any temperature sensor, the temperature sensor is electrically connected to the battery management system, and is used to detect the temperature inside the battery pack and send the detected temperature to the battery management system;

[0069] The battery management system is used to receive the temperature sent by at least one temperature sensor, and to issue an alarm when the temperature sent by at least one temperature sensor meets a first preset condition.

[0070] In this implementation, when any battery cell 16 experiences thermal runaway, gas is ejected through the explosion-proof valve 18 and the fire extinguishing hole 17 corresponding to the explosion-proof valve 18, and the temperature inside the battery pack will increase accordingly. The temperature inside the battery pack is detected by a temperature sensor and the detected temperature is sent to the battery management system.

[0071] The battery management system can determine the average value of the temperature sent by at least one temperature sensor. When the average value is greater than a preset temperature value, it is determined that the first preset condition is met, and a first alarm signal is sent to the control device, and the control device issues an alarm based on the first alarm signal. Alternatively, the battery management system determines the highest temperature from the temperatures sent by at least one temperature sensor. When the highest temperature is greater than a preset temperature value, it is determined that the first preset condition is met, and a first alarm signal is sent to the control device, and the control device issues an alarm based on the first alarm signal.

[0072] The control device may be any controller in the vehicle, and is not specifically limited thereto. For example, the control device may be a vehicle controller or other controller.

[0073] The alarm method can be set and changed as needed, and there is no specific limitation on this, for example, broadcasting a voice alarm message through a voice device, displaying an alarm message through a vehicle display screen, lighting a fault light through an instrument, or other methods.

[0074] In a possible implementation, the battery pack further includes: at least one smoke sensor and a battery management system;

[0075] At least one smoke sensor is electrically connected to the battery management system, and is used to detect the smoke concentration in the battery pack and send the detected smoke concentration to the battery management system;

[0076] The battery management system is used to receive the smoke concentration sent by at least one smoke sensor, and to issue an alarm when the smoke concentration sent by at least one smoke sensor meets a second preset condition.

[0077] In this implementation, when any battery cell 16 experiences thermal runaway, gas is ejected through the explosion-proof valve 18 and the fire extinguishing hole 17 corresponding to the explosion-proof valve 18. The temperature generated by the gas melts the coating film 14, and the fire extinguishing agent 15 in the coating film 14 flows into the battery cell 16 through the explosion-proof valve 18 and the fire extinguishing hole 17 corresponding to the explosion-proof valve 18 to extinguish the fire. Smoke is generated in the battery pack, and the smoke concentration in the battery pack is detected by the smoke sensor, and the detected smoke concentration is sent to the battery management system.

[0078] The battery management system can determine the average value of the smoke concentration sent by at least one smoke sensor. When the average value is greater than a preset concentration value, it is determined that the second preset condition is met, and a second alarm signal is sent to the control device, and the control device issues an alarm based on the second alarm signal. Alternatively, the battery management system determines the highest smoke concentration from the smoke concentrations sent by at least one smoke sensor. When the highest smoke concentration is greater than a preset concentration value, it is determined that the second preset condition is met, and a second alarm signal is sent to the control device, and the control device issues an alarm based on the second alarm signal.

[0079] The way in which the control device issues an alarm based on the second alarm signal may be the same as or different from the way in which the control device issues an alarm based on the first alarm signal, and this is not specifically limited.

[0080] In addition, the electrical connection may be a circuit connection or a wireless connection, which is not specifically limited. If the electrical connection is a circuit connection, the connection method may be a cable connection. If the electrical connection is a wireless connection, the connection method may be a wireless local area network or a WiFi (Wireless Fidelity) network connection. In the embodiments of the present application, this is not specifically limited.

[0081] In one possible implementation, the battery pack includes at least one temperature sensor, at least one smoke sensor and a battery management system at the same time. The implementation method is the same as the above-mentioned implementation method of including at least one temperature sensor and at least one smoke sensor respectively, and will not be repeated here.

[0082] In an embodiment of the present application, a temperature sensor and / or a smoke sensor is used to detect the temperature and / or smoke concentration in the battery pack. When the temperature and / or the smoke concentration is high, an alarm is issued. In this way, the user can promptly know that thermal runaway has occurred in the battery cell 16 in the battery pack, which facilitates timely maintenance of the vehicle.

[0083] It should be noted that when there are multiple temperature sensors, the multiple temperature sensors can be evenly or unevenly arranged on the inner wall of the shell 10; similarly, when there are multiple smoke sensors, the multiple smoke sensors can also be evenly or unevenly arranged on the inner wall of the shell 10.

[0084] In a possible implementation, the fire extinguishing agent 15 includes at least one of the following components: heptafluoropropane, perfluorohexanone, trimethyl phosphate, 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane-2-oxide, 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane, methyl perfluorobutyl ether, tris(2,2,2-trifluoroethyl)phosphite, 1,2-bis(maleimide)ethane, 1,2-phenylene-bis-maleimide and 4,4'-bismaleimidodiphenylmethane.

[0085] In this implementation, the fire extinguishing agent 15 may include one component or multiple components, which is not specifically limited.

[0086] In a possible implementation, the fire extinguishing agent 15 includes: a main fire extinguishing agent and an auxiliary fire extinguishing agent;

[0087] The main fire extinguishing agent includes at least one of 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane-2-oxide, 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane, tris(2,2,2 trifluoroethyl)phosphite, trimethyl phosphate, perfluorohexanone and heptafluoropropane;

[0088] The auxiliary fire extinguishing agent includes at least one of methyl perfluorobutyl ether, 1,2-bis(maleimide)ethane, 1,2-phenylene-bis-maleimide and 4,4'-bismaleimidodiphenylmethane.

[0089] In one possible implementation, when the fire extinguishing agent 15 includes two components, the main fire extinguishing agent is selected from any one of 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane-2-oxide, 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane, tris(2,2,2 trifluoroethyl)phosphite, trimethyl phosphate, perfluorohexanone and heptafluoropropane, and the auxiliary fire extinguishing agent is selected from any one of methyl perfluorobutyl ether, 1,2-bis(maleimide)ethane, 1,2-phenylene-bis-maleimide and 4,4'-bismaleimidodiphenylmethane.

[0090] Moreover, the mass ratio of the main fire extinguishing agent to the auxiliary fire extinguishing agent is 9:1 to 5:5.

[0091] Among them, the mass ratio of the main fire extinguishing agent and the auxiliary fire extinguishing agent can be 9:1, 8:1, 7:1, 6:1, 5:1, 9:2, 8:2, 7:2, 6:2, 5:2, 9:3, 8:3, 7:3, 6:3, 5:3, 9:4, 8:4, 7:4, 6:4, 5:4, 9:5, 8:5, 7:5, 6:5, and 5:5.

[0092] In a possible implementation, when the fire extinguishing agent 15 includes three components, the main fire extinguishing agent can be selected from any one of 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane-2-oxide, 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane, tris(2,2,2 trifluoroethyl)phosphite, trimethyl phosphate, perfluorohexanone and heptafluoropropane, and the auxiliary fire extinguishing agent is selected from two of methyl perfluorobutyl ether, 1,2-bis(maleimide)ethane, 1,2-phenylene-bis-maleimide, and 4,4'-bismaleimidodiphenylmethane;

[0093] In this implementation, the auxiliary fire extinguishing agent may include a first auxiliary fire extinguishing agent and a second auxiliary fire extinguishing agent, and a mass ratio of the main fire extinguishing agent, the first auxiliary fire extinguishing agent, and the second auxiliary fire extinguishing agent is 8:1:1 to 1:1:1.

[0094] Among them, the mass ratio of the main fire extinguishing agent, the first auxiliary fire extinguishing agent and the second auxiliary fire extinguishing agent can be 8:1:1, 7:1:1, 6:1:1, 5:1:1, 4:1:1, 3:1:1, 2:1:1, 1:1:1, 7:2:1, 6:2:1, and there is no specific limitation on this.

[0095] In one possible implementation, when the fire extinguishing agent 15 includes three components, the main fire extinguishing agent can also be selected from two of 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane-2-oxide, 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane, tris(2,2,2 trifluoroethyl)phosphite, trimethyl phosphate, perfluorohexanone and heptafluoropropane, and the auxiliary fire extinguishing agent is selected from any one of methyl perfluorobutyl ether, 1,2-bis(maleimide)ethane, 1,2-phenylene-bis-maleimide and 4,4'-bismaleimidodiphenylmethane.

[0096] In this implementation, the main fire extinguishing agent may include a first main fire extinguishing agent and a second main fire extinguishing agent, and the mass ratio of the first main fire extinguishing agent, the second main fire extinguishing agent and the auxiliary fire extinguishing agent is 8:1:1 to 1:1:1.

[0097] Among them, the mass ratio of the first main fire extinguishing agent, the second main fire extinguishing agent and the auxiliary fire extinguishing agent can be 8:1:1, 7:1:1, 6:1:1, 5:1:1, 4:1:1, 3:1:1, 2:1:1, 1:1:1, 7:2:1, 6:2:1, 5:2:1, 4:2:1, 3:2:1, 2:2:1, and there is no specific limitation on this.

[0098] Of course, the fire extinguishing agent 15 may also include four components or even more components, which are not listed here one by one.

[0099] In the embodiment of the present application, the fire extinguishing agent 15 is contained in the coating film 14, wherein the fire extinguishing agent 15 can be evenly coated on the coating film 14, or directly contained in the coating film 14, which is not specifically limited. The accumulation amount of the fire extinguishing agent 15 in the coating film 14 can be set and changed as needed, which is not specifically limited. For example, the accumulation amount of the fire extinguishing agent 15 in the coating film 14 is 0.2g / cm 2 ~0.5g / cm 2 .

[0100] The accumulated amount of the fire extinguishing agent 15 in the coating film 14 can be 0.2 g / cm 2 , 0.25g / cm 2 , 0.3g / cm 2 , 0.35g / cm 2 , 0.4g / cm 2 , 0.45g / cm 2 , 0.5g / cm 2 .

[0101] The fire extinguishing agent 15 provided in the embodiment of the present application can absorb a large amount of heat in a short period of time, rapidly reduce the temperature inside the battery cell 16, and can also form a protective barrier to prevent air from contacting the fire source, further suppressing the spread of the fire.

[0102] In summary, the battery pack provided in the present application can automatically extinguish fire to suppress heat spread after thermal runaway occurs in a single battery cell 16, and the device is simple and reliable, and has a significant fire extinguishing effect.

[0103] An embodiment of the present application also provides a vehicle, which includes the battery pack introduced above.

[0104] The vehicle may be an electric vehicle or a hybrid vehicle, without any specific limitation.

[0105] The technical solution of the present application will be described in detail below through specific embodiments.

[0106] In the following specific examples, operations involved without specifying conditions were performed under conventional conditions or conditions recommended by the manufacturer.

[0107] Example 1

[0108] This embodiment provides a battery pack, which includes: a shell, and a battery module, a bracket cover, a mica board, a coating film and a fire extinguishing agent located in the shell; the bracket cover is located above the battery module, with an inclination of 3° relative to the bottom surface of the shell, and the mica board is located above the bracket cover; the battery module includes 90 to 200 battery cells depending on the battery type; accordingly, 90 to 200 fire extinguishing holes are opened on the bracket cover, and each fire extinguishing hole corresponds to the explosion-proof valve on the battery cell; the coating film is fixed on the bracket cover, and the fire extinguishing agent is contained in the coating film. For example, if the battery module includes 100 battery cells, 100 fire extinguishing holes are opened on the bracket cover.

[0109] The fire extinguishing agent is 4,4'-bismaleimidodiphenylmethane, the material of the coating is PE, and the accumulation of the fire extinguishing agent in the coating is 0.2g / cm 2 , the coating thickness is 20μm.

[0110] When the temperature of any battery cell exceeds 120°C, the coating begins to melt and decompose, releasing the fire extinguishing agent, thereby achieving automatic fire extinguishing.

[0111] Example 2

[0112] This embodiment provides a battery pack, and the structure of the battery pack is the same as that of Embodiment 1.

[0113] The fire extinguishing agent is perfluorohexanone, the material of the coating is PE, and the accumulation of the fire extinguishing agent in the coating is 0.2g / cm 2, the coating thickness is 20μm.

[0114] When the temperature of any battery cell exceeds 120°C, the coating begins to melt and decompose, releasing the fire extinguishing agent, thereby achieving automatic fire extinguishing.

[0115] Example 3

[0116] This embodiment provides a battery pack, and the structure of the battery pack is the same as that of Embodiment 1.

[0117] The fire extinguishing agent is a mixture of 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane-2-oxide and 4,4'-bismaleimidodiphenylmethane, the mixing ratio of the two is 7:3, the material of the coating is PE, and the accumulation of the fire extinguishing agent in the coating is 0.2g / cm 2 , the coating thickness is 20μm.

[0118] When the temperature of any battery cell exceeds 120°C, the coating begins to melt and decompose, releasing the fire extinguishing agent, thereby achieving automatic fire extinguishing.

[0119] Example 4

[0120] This embodiment provides a battery pack, and the structure of the battery pack is the same as that of Embodiment 1.

[0121] The fire extinguishing agent is a mixture of perfluorohexanone and methyl perfluorobutyl ether, the mixing ratio of the two is 6:4, the material of the coating is PE, and the accumulation of the fire extinguishing agent in the coating is 0.3g / cm 2 , the coating thickness is 30μm.

[0122] When the temperature of any battery cell exceeds 120°C, the coating begins to melt and decompose, releasing the fire extinguishing agent, thereby achieving automatic fire extinguishing.

[0123] Example 5

[0124] This embodiment provides a battery pack, and the structure of the battery pack is the same as that of Embodiment 1.

[0125] The fire extinguishing agent is a mixture of 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane and methyl perfluorobutyl ether, the mixing ratio of the two is 8:2, the coating material is a urea-formaldehyde polymer film, and the accumulation of the fire extinguishing agent in the coating is 0.4g / cm 2 , the coating thickness is 40μm.

[0126] When the temperature of any battery cell exceeds 130°C, the coating begins to melt and decompose, releasing the fire extinguishing agent, thereby achieving automatic fire extinguishing.

[0127] Example 6

[0128] This embodiment provides a battery pack, and the structure of the battery pack is the same as that of Embodiment 1.

[0129] The fire extinguishing agent is a mixture of perfluorohexanone, trimethyl phosphate and 1,2-bis(maleimide)ethane, the mixing ratio of the three is 7:2:1, the material of the coating film is PP film, and the accumulation of the fire extinguishing agent in the coating film is 0.4g / cm 2 , the coating thickness is 30μm.

[0130] When the temperature of any battery cell exceeds 160°C, the coating begins to melt and decompose, releasing the fire extinguishing agent, thereby achieving automatic fire extinguishing.

[0131] Example 7

[0132] This embodiment provides a battery pack, and the structure of the battery pack is the same as that of Embodiment 1.

[0133] The fire extinguishing agent is a mixture of heptafluoropropane, trimethyl phosphate and 1,2-bis(maleimide)ethane, the mixing ratio of the three is 8:1:1, the coating material is PP film, and the accumulation of the fire extinguishing agent in the coating is 0.4g / cm 2 , the coating thickness is 30μm.

[0134] When the temperature of any battery cell exceeds 160°C, the coating begins to melt and decompose, releasing the fire extinguishing agent, thereby achieving automatic fire extinguishing.

[0135] The above description is only for the purpose of facilitating those skilled in the art to understand the technical solution of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery pack, characterized in that: The battery pack comprises: a shell (10), and a battery module (11), a bracket cover plate (12), a mica plate (13), a coating film (14), and a fire extinguishing agent (15) located in the shell (10); The support cover plate (12) is located above the battery module (11) and has a preset inclination angle relative to the bottom surface of the shell (10); and the mica board (13) is located above the support cover plate (12); The battery module (11) comprises a plurality of battery cells (16); A plurality of fire extinguishing holes (17) are provided on the support cover plate (12), and each fire extinguishing hole (17) corresponds to an explosion-proof valve (18) on the battery cell (16); The coating film (14) is fixed on the bracket cover plate (12), and the fire extinguishing agent (15) is contained in the coating film (14); When any battery cell (16) in the battery module (11) experiences thermal runaway, the explosion-proof valve (18) corresponding to the battery cell (16) opens, and gas is ejected through the explosion-proof valve (18) and the fire extinguishing hole (17) corresponding to the explosion-proof valve (18), and the temperature generated by the gas melts the coating film (14), and the fire extinguishing agent (15) in the coating film (14) flows into the battery cell (16) through the explosion-proof valve (18) and the fire extinguishing hole (17) corresponding to the explosion-proof valve (18).

2. The battery pack according to claim 1, characterized in that: The coating film (14) comprises a plurality of partition spaces (141), wherein the plurality of partition spaces (141) are respectively located on both sides of the continuous channel (142) and are all in communication with the continuous channel (142); Each partition space (141) contains the fire extinguishing agent (15).

3. The battery pack according to claim 1, characterized in that: The fire extinguishing agent (15) comprises at least one of the following components: heptafluoropropane, perfluorohexanone, trimethyl phosphate, 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane-2-oxide, 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane, methyl perfluorobutyl ether, tris(2,2,2-trifluoroethyl)phosphite, 1,2-bis(maleimide)ethane, 1,2-phenylene-bis-maleimide and 4,4'-bismaleimidodiphenylmethane.

4. The battery pack according to claim 3, characterized in that: The fire extinguishing agent (15) comprises a main fire extinguishing agent and an auxiliary fire extinguishing agent; The main fire extinguishing agent includes at least one of 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane-2-oxide, 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane, tris(2,2,2 trifluoroethyl)phosphite, trimethyl phosphate, perfluorohexanone and heptafluoropropane; The auxiliary fire extinguishing agent includes at least one of methyl perfluorobutyl ether, 1,2-bis(maleimide)ethane, 1,2-phenylene-bis-maleimide and 4,4'-bismaleimidodiphenylmethane.

5. The battery pack according to claim 4, characterized in that: The mass ratio of the main fire extinguishing agent to the auxiliary fire extinguishing agent is 9:1 to 5:

5.

6. The battery pack according to claim 4, characterized in that: The main fire extinguishing agent includes a first main fire extinguishing agent and a second main fire extinguishing agent; The mass ratio of the first main fire extinguishing agent, the second main fire extinguishing agent and the auxiliary fire extinguishing agent is 8:1:1 to 1:1:

1.

7. The battery pack according to claim 1, characterized in that: The accumulation amount of the fire extinguishing agent (15) in the coating film (14) is 0.2 g / cm 2 ~0.5g / cm 2 .

8. The battery pack according to claim 1, characterized in that: The coating film (14) comprises at least one of polyethylene, polypropylene, chitosan and urea-formaldehyde polymer.

9. The battery pack according to claim 8, characterized in that: The coating film (14) has a thickness of 20 μm to 50 μm.

10. A vehicle, characterized in that: The vehicle comprises the battery pack according to any one of claims 1 to 9.

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