Energy storage equipment and electric equipment

Abstract

The invention discloses energy storage equipment and electric equipment, and relates to the technical field of safety of energy storage equipment. The energy storage equipment comprises a box body, a battery module and a box cover assembly, the battery module is arranged in the box body and comprises a plurality of single batteries, and the box cover assembly comprises a box cover and a plurality of temperature detection devices. The box cover is arranged on the box body, a containing space is defined by the box body and the box cover, and the battery module is arranged in the containing space; the plurality of temperature detection devices are arranged on the bottom surface, opposite to the box body, of the box cover and are respectively opposite to the anti-explosion valves of the plurality of single batteries.

Description

Technical Field

[0001] The present application relates to the technical field of safety of energy storage devices, and in particular to an energy storage device and an electrical device. Background Art

[0002] Energy storage equipment is generally composed of multiple battery cells. If one of the battery cells goes out of control, it is easy to cause heat spread throughout the module, leading to more serious safety accidents. Therefore, preventing and detecting the safety status of the battery is an important basic and necessary function to ensure the safety of the module. Existing detection methods rely on battery voltage and the temperature of the positive and negative pole areas. Summary of the invention

[0003] The embodiments of the present application provide an energy storage device and an electrical device, which detects the temperature of the combustible gas ejected from the relatively arranged explosion-proof valve due to thermal runaway through a temperature detection device on a box cover assembly, thereby timely detecting the thermal runaway, which is conducive to timely handling of the thermal runaway and improving the safety of the energy storage device.

[0004] In the energy storage device of the embodiment of the present application, the energy storage device includes a box body, a battery module and a box cover assembly, the battery module is arranged in the box body, the battery module includes a plurality of battery cells, the box cover assembly includes a box cover and a plurality of temperature detection devices, the box cover is arranged in the box body, the box body and the box cover form a receiving space, and the battery module is arranged in the receiving space; a plurality of temperature detection devices, the plurality of temperature detection devices are arranged on the bottom surface of the box cover opposite to the box body, and the plurality of temperature detection devices are respectively arranged opposite to the explosion-proof valves of the plurality of battery cells.

[0005] In some embodiments, the temperature detection device includes a bimetallic thermal switch or a thermistor thermal switch.

[0006] In some embodiments, the bimetallic thermal switch includes a first metal part and a second metal part, the first metal part and the second metal part have different thermal expansion coefficients, the first metal part and the second metal part are disconnected when the temperature is greater than a preset temperature, and are connected when the temperature is less than the preset temperature.

[0007] In some embodiments, a plurality of the temperature detection devices are connected in series to form a detection loop, and the detection loop further includes a power supply and a signal collector, and the signal collector is used to collect the current of the detection loop.

[0008] In some embodiments, the energy storage device further includes a battery management system, which is used to obtain the current collected by the signal collector, and the battery management system is configured to determine that the energy storage device has a risk of thermal runaway when the current is not zero.

[0009] In some embodiments, the temperature detection device includes a temperature sensor, and the temperature detection sensor is used to detect the temperature of the area where the explosion-proof valve of the battery cell is located.

[0010] In some embodiments, the energy storage device also includes a battery management system, which is used to obtain detection information of the temperature detection device. The battery management system is configured to determine that the energy storage device is at risk of thermal runaway when it is determined based on the detection information that the temperature of any battery cell is greater than a preset temperature.

[0011] In some embodiments, the preset temperature is 80 degrees.

[0012] In some embodiments, the battery cells and the temperature detection devices are arranged in a one-to-one correspondence; or, a plurality of the battery cells are divided into a plurality of battery groups, and the temperature detection devices and the battery groups are arranged in a one-to-one correspondence.

[0013] In some embodiments, the temperature detection device and the corresponding explosion-proof valve of the battery cell are arranged opposite to each other.

[0014] In some embodiments, the distance between the temperature detection device and the corresponding explosion-proof valve of the battery cell is less than a preset distance.

[0015] In some embodiments, the size of the temperature detection device is determined based on the size of the corresponding explosion-proof valve of the battery cell.

[0016] In some embodiments, the battery cell includes a battery core and a battery casing, and the explosion-proof valve is located at a central position of a surface of the battery casing corresponding to the box cover.

[0017] In some embodiments, the battery management system is used to obtain detection information from the temperature detection device, and the battery management system is configured to generate thermal runaway information based on the detection information, and determine whether to perform a thermal runaway management operation based on at least one of the thermal runaway information and battery operation information, the thermal runaway management operation including disconnecting the power supply circuit of the battery module and issuing at least one of a thermal runaway prompt message.

[0018] The electrical equipment of the present application includes the energy storage device of any of the above-mentioned embodiments.

[0019] In the energy storage device and the electrical equipment of the embodiment of the present application, the box cover and the box body form a storage space for accommodating the battery module. A plurality of temperature detection devices are arranged on the bottom surface of the box cover opposite to the battery module. The temperature detection device is arranged opposite to the explosion-proof valve of the battery cell. In the case of thermal runaway of any battery cell, the battery cell continuously generates high-temperature gas, causing the pressure of the battery cell to continuously increase. The explosion-proof valve automatically releases the pressure, thereby ejecting the high-temperature gas. At this time, the temperature detection device arranged opposite to the battery cell can timely detect the temperature change caused by the high-temperature gas, thereby realizing timely detection of thermal runaway. Compared with the parallel battery, the voltage of one battery cell remains basically unchanged after thermal runaway, and the voltage change is detected only after the thermal runaway spreads to each battery cell, and the thermal runaway detection is relatively delayed; or, after the thermal runaway continues to spread, the temperature of the positive and negative pole regions will gradually rise, thereby detecting the thermal runaway, and the thermal runaway detection is relatively delayed. In the present application, the timeliness of thermal runaway detection by detecting the temperature change of the explosion-proof valve is high, which is conducive to timely handling of thermal runaway and improving the safety of energy storage equipment.

[0020] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the embodiments of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0022] Figure 1 It is a schematic diagram of the structure of the energy storage device of certain embodiments of the present application.

[0023] Figure 2 It is a schematic diagram of the internal structure of the energy storage device of certain embodiments of the present application.

[0024] Figure 3 It is a schematic diagram of the structure of a box cover assembly of an energy storage device in certain embodiments of the present application.

[0025] Figure 4 It is a schematic diagram of the structure of the temperature detection device in some embodiments of the present application when it is in the on state.

[0026] Figure 5 It is a schematic diagram of the structure of the temperature detection device in some embodiments of the present application in a disconnected state.

[0027] Figure 6 It is a schematic diagram of the structure of electrical equipment in certain embodiments of the present application. DETAILED DESCRIPTION

[0028] The following further describes the embodiments of the present application in conjunction with the accompanying drawings. The same or similar reference numerals in the accompanying drawings represent the same or similar elements or elements with the same or similar functions.

[0029] In addition, the embodiments of the present application described below in conjunction with the drawings are exemplary and are only used to explain the embodiments of the present application and should not be construed as limiting the present application.

[0030] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0031] Thermal runaway of a battery refers to the phenomenon that under certain conditions, an uncontrollable exothermic reaction occurs inside the battery, causing the temperature to rise sharply. Thermal runaway is usually caused by a runaway chemical reaction inside the battery, which generates a large amount of heat that cannot be dissipated in time, thus triggering a series of chain reactions. This situation is particularly common in lithium-ion batteries, but it may also occur in other types of batteries.

[0032] (1) Causes of thermal runaway

[0033] Overcharge or over discharge: When a battery is overcharged or over discharged, the internal chemical reaction becomes unstable, causing the temperature to rise.

[0034] Internal short circuit: When a short circuit occurs inside the battery, the current will bypass the normal path and flow directly, generating a lot of heat.

[0035] External short circuit: When the positive and negative poles of the battery are in direct contact, an external short circuit occurs, causing the current to increase sharply and generate a lot of heat.

[0036] Mechanical damage: Mechanical damage to the battery, such as impact or squeezing, may cause damage to the internal structure and lead to a short circuit.

[0037] High temperature environment: If the battery is exposed to high temperature for a long time, the chemical substances inside the battery may decompose faster and generate heat.

[0038] Manufacturing defects: Defects in the battery manufacturing process, such as diaphragm rupture, electrolyte leakage, etc., may also lead to thermal runaway.

[0039] (2) The process of thermal runaway. The process of thermal runaway can usually be divided into the following stages:

[0040] Initial warming up: For some reason, the battery starts to warm up.

[0041] Accelerated internal reactions: As the temperature rises, the rate of chemical reactions inside the battery increases, generating more heat.

[0042] Thermal runaway trigger: When the temperature reaches a critical value, a positive feedback loop inside the battery begins, generating a large amount of heat energy, causing the temperature to rise rapidly.

[0043] Gas release: The electrolyte inside the battery begins to decompose and release gases (such as hydrogen, oxygen, etc.).

[0044] Fire and explosion: In extreme cases, the battery may catch fire or even explode.

[0045] (3) Consequences of thermal runaway

[0046] Thermal runaway not only has a serious impact on the performance of the battery itself, but may also bring serious safety hazards:

[0047] Performance degradation: The battery life is greatly shortened and performance is reduced.

[0048] Fire risk: Thermal runaway may cause the battery to catch fire, resulting in property damage.

[0049] Explosion Hazard: In extreme cases, the battery may explode, endangering personal safety.

[0050] (4) Once the battery shows signs of thermal runaway, the following emergency measures can be taken:

[0051] Power off: Cut off the power supply immediately to prevent the current from continuing to flow through the battery.

[0052] Isolation: Isolate the affected battery to prevent it from affecting other batteries.

[0053] Cooling: Use water or other coolants to cool the battery and reduce the temperature.

[0054] Evacuation: If necessary, evacuate the scene immediately to ensure personal safety.

[0055] Therefore, timely detection is crucial for thermal runaway. Existing thermal runaway detection is generally achieved through battery voltage and the temperature of the positive and negative pole areas. However, the detection of battery voltage and the temperature of the positive and negative pole areas is relatively lagging, and can generally only be detected when the thermal runaway spreads to a high degree, resulting in poor timeliness in the detection of thermal runaway, and thus the inability to handle thermal runaway in a timely manner, resulting in low safety of the energy storage module.

[0056] For the solution of detecting thermal runaway by detecting battery voltage, in energy storage equipment, when multiple batteries are connected in parallel, even if one of the batteries has thermal runaway, the voltage of the battery module will remain unchanged if the thermal runaway has not spread. This requires the thermal runaway to spread to each battery before the voltage change of the battery module can be detected. Therefore, the solution of detecting thermal runaway by detecting battery voltage has a relatively delayed detection of thermal runaway and low timeliness of detection.

[0057] For the scheme of detecting thermal runaway by detecting the temperature of the positive and negative poles, in the energy storage device, if one of the batteries has thermal runaway, and the thermal runaway has not spread, the temperature of the positive and negative poles will rise slowly. This requires the thermal runaway to spread to each battery, and only then can it be detected that the temperature of the positive and negative poles reaches the thermal runaway temperature threshold. Therefore, the scheme of detecting thermal runaway by detecting the temperature of the positive and negative poles has a relatively delayed detection of thermal runaway and low timeliness of detection.

[0058] See also Figures 1 to 3 In order to timely detect the thermal runaway of the energy storage device 100, the present application provides an energy storage device 100, which includes a box cover assembly 10, a box body 20, and a battery module 30. The battery module 30 is arranged in the box body 20, and the battery module 30 includes a plurality of battery cells 31. The box cover assembly 10 includes a box cover 11 and a plurality of temperature detection devices 12. The box cover 11 is arranged in the box body 20, and the box body 20 and the box cover 11 enclose a receiving space 40, and the battery module 30 is arranged in the receiving space 40; a plurality of temperature detection devices 12 are arranged on the bottom surface 111 of the box cover 11 opposite to the box body 20, and the plurality of temperature detection devices 12 are respectively arranged opposite to the explosion-proof valves 311 of the plurality of battery cells 31.

[0059] In the box cover assembly 10 of the embodiment of the present application, the box cover 11 and the box body 20 of the energy storage device 100 form a receiving space 40 for receiving the battery module 30. A plurality of temperature detection devices 12 are arranged on the bottom surface 111 of the box cover 11 opposite to the battery module 30. The temperature detection devices 12 are arranged opposite to the explosion-proof valve 311 of the battery cell 31. In the case of thermal runaway of any battery cell 31, the battery cell 31 continuously generates high-temperature gas, causing the pressure of the battery cell 31 to continuously increase. The explosion-proof valve 311 automatically releases pressure, thereby ejecting the high-temperature gas. At this time, the temperature detection device 12 arranged opposite to the battery cell 31 The temperature change caused by high-temperature gas can be detected in time, thereby realizing timely detection of thermal runaway. Compared with parallel batteries, the voltage of one battery cell 31 remains basically unchanged after thermal runaway, and it is necessary to wait for the thermal runaway to spread to each battery cell 31 before detecting the voltage change, and the thermal runaway detection is relatively delayed; or, after the thermal runaway continues to spread, the temperature of the positive and negative pole areas will gradually rise, thereby detecting the thermal runaway, and the thermal runaway detection is relatively delayed. In this application, the timeliness of thermal runaway detection achieved by detecting the temperature change of the explosion-proof valve 311 is higher, which is conducive to timely handling of thermal runaway and improving the safety of the energy storage device 100.

[0060] See also Figure 2 The present application provides an energy storage device 100, which includes a box cover assembly 10, a box body 20, and a battery module 30. The box cover assembly 10 is disposed on the box body 20, the box body 20 and the box cover assembly 10 enclose a receiving space 40, and the battery module 30 is disposed in the receiving space 40.

[0061] See also Figure 3 In some embodiments, the box cover assembly 10 includes a box cover 11 and a plurality of temperature detection devices 12. The plurality of temperature detection devices 12 are disposed on a bottom surface 111 of the box cover 11 opposite to the battery module 30, or in other words, are installed on a surface of the box cover 11 located in the receiving space 40.

[0062] The box cover 11 is used to seal the receiving space 40 to isolate the receiving space 40 from the outside world and prevent dust, conductive materials, etc. from entering the receiving space 40 to ensure the safety and life of the battery module 30.

[0063] Optionally, the box cover 11 is fixedly mounted on the box body 20 ; or the box cover 11 is detachably mounted on the box body 20 , so as to facilitate subsequent maintenance of the battery module 30 .

[0064] The temperature detection device 12 is a device for detecting temperature, or a device that is sensitive to temperature and changes with temperature.

[0065] For example, the temperature detection device 12 can be a temperature sensor, which is used to detect the temperature of the area where the explosion-proof valve 311 of the relative battery cell 31 is located. The temperature sensor can detect any temperature within a preset temperature range; for example, the temperature sensor can be a thermocouple, a thermistor, an infrared temperature sensor, etc.

[0066] When the temperature detection device 12 detects that the temperature is greater than the preset temperature, it will output thermal runaway information to the battery management system (BMS) of the energy storage device 100, thereby assisting the battery management system in thermal runaway management, such as power off, issuing thermal runaway prompt information, etc. And because the temperature detection device 12 and the battery cell 31 are arranged relative to each other, the thermal runaway information output by the temperature detection device 12 includes not only the information that the battery cell 31 has thermal runaway, but also the location information of the battery cell 31 that has thermal runaway, thereby facilitating the subsequent accurate processing of thermal runaway.

[0067] See also Figure 4 For another example, the temperature detection device 12 may be a thermal switch, which is a temperature-sensitive switch device that can automatically open or close a circuit when a preset temperature is reached. For example, the thermal switch may be a bimetallic thermal switch, a thermistor (NTC (Negative Temperature Coefficient, negative temperature coefficient thermistor) and PTC (Positive Temperature Coefficient, positive temperature coefficient thermistor)) thermal switch, etc.

[0068] Please combine Figure 4 and Figure 5 Taking a bimetallic thermal switch as an example, the bimetallic thermal switch includes a first metal member 121 and a second metal member 122. The first metal member 121 and the second metal member 122 have different thermal expansion coefficients. Therefore, as the temperature rises, the first metal member 121 and the second metal member 122 expand to different degrees. When the temperature is lower than the preset temperature, the expansion degree is low. At this time, the first metal member 121 and the second metal member 122 remain connected, and the switch is in the on state. When the temperature is higher than the preset temperature, the expansion degree is high. At this time, the first metal member 121 and the second metal member 122 are disconnected, and the switch is in the off state. Compared with temperature sensors, thermal switches have lower costs, so a corresponding thermal switch can be set on the box cover 11 for each battery cell 31.

[0069] When the thermal switch detects that the temperature is greater than the preset temperature, the thermal switch is disconnected, and the energy storage device 100 can detect the on / off state of the thermal switch, thereby realizing the detection of thermal runaway, and obtaining thermal runaway information, thereby assisting the battery management system 50 in thermal runaway management, such as power off, issuing thermal runaway prompt information, etc. And because the temperature detection device 12 and the battery cell 31 are arranged relative to each other, the thermal runaway information output by the temperature detection device 12 includes not only the information that the battery cell 31 has thermal runaway, but also the location information of the battery cell 31 that has thermal runaway, thereby facilitating the subsequent accurate processing of thermal runaway.

[0070] Optionally, the preset temperature is 80 degrees. By setting a reasonable temperature threshold for determining whether thermal runaway exists, the accuracy of thermal runaway determination can be ensured. It can be understood that the preset temperature is an empirical value, which can be determined by detecting the temperature near the explosion-proof valve 311 when the battery has thermal runaway; and / or, by detecting the temperature near the explosion-proof valve 311 when the battery module 30 is working normally.

[0071] See also Figure 2 and Figure 3 Optionally, a plurality of temperature detection devices 12 are connected in series to form a detection loop, and the detection loop also includes a power supply 13 and a signal collector 14. The signal collector 14 is used to collect the current of the detection loop. When any temperature detection device 12 is disconnected, the current is 0. The battery management system 50 is used to obtain the current collected by the signal collector 14. The battery management system 50 is configured to determine that the energy storage device 100 has a risk of thermal runaway when the current is not 0.

[0072] In order to reduce the circuit complexity of thermal runaway detection, multiple thermal switches can be connected in series to form a detection loop. When any thermal switch detects thermal runaway and disconnects, the detection loop is disconnected. The battery management system 50 can determine whether thermal runaway occurs in the battery module 30 by detecting the on / off state of the detection loop (that is, whether the current in the detection loop is 0).

[0073] For example, the detection circuit can be provided with a signal collector 14 to collect the current of the detection circuit, and a power supply 13 can be provided to supply power, so that the signal collector 14 can maintain operation. When each thermal switch of the detection circuit is turned on, due to the action of the power supply 13, there is current in the detection circuit, and when the signal collector 14 collects a current that is not zero, it can be determined that the battery module 30 has thermal runaway; and when any thermal switch of the detection circuit is disconnected, the current in the detection circuit becomes 0, and at this time it can be determined that the battery module 30 does not have thermal runaway.

[0074] The signal collector 14 can also be connected to the battery management system 50 for communication. When the battery module 30 is detected to be in thermal runaway, the thermal runaway information is output to the battery management system 50, or the battery management system 50 can obtain the current collected by the signal collector 14 to determine whether the battery module 30 is in thermal runaway. Compared with each thermal switch forming a loop, it is necessary to set a power supply 13 and a signal collector 14 in each loop, which has a high circuit complexity and high cost. When multiple thermal switches are connected in series to form a detection loop, the circuit complexity and cost are both low.

[0075] In addition, when the battery cells 31 and the thermal switches correspond one to one, if each thermal switch forms a separate detection circuit, as the number of battery cells 31 increases, the number of detection circuits increases, and the amount of signal samples required to be collected also increases, which will increase the computing load of the battery management system 50, and easily cause the BMS to crash or fail, thereby causing the BMS to be unable to respond in time in the event of thermal runaway, thereby reducing the safety of the energy storage device 100.

[0076] Optionally, in order to timely detect thermal runaway of each battery cell 31 of the battery module 30 , the temperature detection device 12 may be disposed at the location of the explosion-proof valve 311 of each battery cell 31 , such as the temperature detection device 12 and the explosion-proof valve 311 are disposed opposite to each other.

[0077] Among them, the relative arrangement of the temperature detection device 12 and the explosion-proof valve 311 means that the temperature detection device 12 and the corresponding explosion-proof valve 311 are arranged opposite each other; or, the temperature detection device 12 is arranged in the range covered by the ejected gas on the bottom surface of the box cover 11 when the corresponding explosion-proof valve 311 releases pressure; or, the temperature detection device 12 is arranged in the projection area of ​​the valve mouth of the corresponding explosion-proof valve 311 on the bottom surface of the box cover 11.

[0078] When the battery cell 31 is in thermal runaway, the electrolyte inside the battery cell 31 decomposes and releases gas, causing the pressure inside the battery cell 31 to continue to rise. When the pressure inside the battery cell 31 is greater than the preset pressure, the explosion-proof valve 311 opens to release pressure to avoid explosion. When releasing pressure, the explosion-proof valve 311 sprays high-temperature gas, and the temperature detection device 12 can detect the high temperature caused by the high-temperature gas, thereby detecting that the relative battery cell 31 has thermal runaway. When the thermal runaway has not spread to other battery cells 31, the thermal runaway of the battery cell 31 is detected in time, and the timeliness of the detection of thermal runaway is high.

[0079] Optionally, the plurality of temperature detection devices 12 are respectively disposed opposite to the explosion-proof valves 311 of the plurality of battery cells 31 , and the temperature detection devices 12 and the explosion-proof valves 311 are disposed in a one-to-one correspondence.

[0080] Optionally, when the temperature detection device 12 and the explosion-proof valve 311 are set in one-to-one correspondence, the temperature detection device 12 and the corresponding explosion-proof valve 311 are directly opposite, that is, the distance between the projection of the center of the temperature detection device 12 on the surface where the corresponding explosion-proof valve 311 is located and the center of the corresponding explosion-proof valve 311 is less than a predetermined distance (such as 1 mm, 0.5 mm, etc.).

[0081] Optionally, the distance between the temperature detection device 12 and the corresponding explosion-proof valve 311 is smaller than a preset distance.

[0082] It is understandable that when the battery cell 31 is in thermal runaway, the explosion-proof valve 311 will release pressure and spray gas. If the temperature detection device 12 is too far away from the explosion-proof valve 311, the temperature of the area detectable by the temperature detection device 12 may not reach the preset temperature until the explosion-proof valve 311 has sprayed gas multiple times, resulting in delayed thermal runaway detection and poor timeliness of thermal runaway detection.

[0083] The distance between the temperature detection device 12 and the corresponding explosion-proof valve 311 may be the maximum distance between the temperature detection device 12 and the corresponding explosion-proof valve 311 ; or, the distance between the center of the temperature detection device 12 and the center of the corresponding explosion-proof valve 311 .

[0084] Therefore, setting the distance between the temperature detection device 12 and the corresponding explosion-proof valve 311 to be less than the preset distance can ensure that as long as the explosion-proof valve 311 sprays gas, it will be detected in time by the temperature detection device 12, thereby detecting thermal runaway in time.

[0085] Optionally, the size of the temperature detection device 12 is determined based on the size of the explosion-proof valve 311 of the corresponding battery cell 31 .

[0086] It can be understood that the larger the size of the explosion-proof valve 311, the larger the coverage space of the pressure-released gas. The temperature detection device 12 (such as a thermistor) should be set in the coverage space to avoid the temperature detection device 12 from lagging in detecting thermal runaway, or even failing to detect thermal runaway.

[0087] The larger the size of the thermal switch, the higher the cost. Therefore, the size of the temperature detection device 12 can be determined based on the size of the corresponding explosion-proof valve 311. For example, the size of the temperature detection device 12 is positively correlated with the size of the explosion-proof valve 311, so that the temperature detection device 12 can always be located within the coverage of the gas ejected by the explosion-proof valve 311. In this way, the cost of the temperature detection device 12 can be reduced while ensuring the timeliness of thermal runaway detection.

[0088] Optionally, the plurality of temperature detection devices 12 are respectively arranged opposite to the explosion-proof valves 311 of the plurality of battery cells 31 , or the temperature detection devices 12 and the battery packs are arranged in a one-to-one correspondence.

[0089] Multiple battery cells 31 are divided into multiple battery groups. The temperature detection device 12 and the battery group are set in a one-to-one correspondence. The temperature detection device 12 can be set in the area on the ground of the box cover 11 that is opposite to the corresponding battery group. When any battery cell 31 of the battery group has thermal runaway, the explosion-proof valve 311 of the runaway battery cell 31 sprays high-temperature gas, and the temperature detection device 12 can detect the high temperature caused by the high-temperature gas, thereby detecting that the relative battery cell 31 has thermal runaway. When the thermal runaway has not spread to other battery cells 31, the thermal runaway of the battery cell 31 is detected in time, and the timeliness of the thermal runaway detection is high. When the temperature detection device 12 and the battery group have a one-to-one correspondence, the number of temperature detection devices 12 can be reduced, and the cost of thermal runaway detection can be reduced.

[0090] Optionally, the temperature detection device 12 is directly opposite to the explosion-proof valve 311 of the battery cell 31 located at the center in the corresponding battery pack; or, the temperature detection device 12 is directly opposite to the center position of multiple explosion-proof valves 311 in the corresponding battery pack. In this way, the distance between the temperature detection device 12 and each battery cell 31 is relatively uniform and close, which can avoid the problem of delayed thermal runaway detection when the distance from any battery cell 31 is far. While reducing the number of temperature detection devices 12, the timeliness of thermal runaway detection is guaranteed.

[0091] Optionally, after the temperature detection device 12 is set, the distance between the temperature detection device 12 and each explosion-proof valve 311 in the corresponding battery pack can be detected. If the distance between any explosion-proof valve 311 and the temperature detection device 12 is greater than a preset distance, the number of each battery pack is adjusted (such as reducing the number of battery cells in the battery pack), thereby ensuring that the distance between the temperature detection device 12 and each explosion-proof valve 311 in the corresponding battery pack is less than the preset distance, thereby ensuring the timeliness of the detection of the temperature detection device 12.

[0092] Please refer again Figure 1 In some embodiments, the box body 20 includes a bottom wall and a side wall, the side wall is arranged on the bottom wall, and the side wall, the bottom wall and the box cover 11 form a receiving space 40.

[0093] The housing 20 is usually made of metal (such as steel, aluminum alloy) or high-strength plastic to ensure sufficient strength and durability. When designing the housing 20, factors such as waterproof, dustproof, and shockproof need to be considered. Common protection levels include IP65, IP67, etc. In order to ensure good heat dissipation performance of the battery module 30, the housing 20 is usually designed with a heat dissipation system such as ventilation holes or a built-in fan.

[0094] In some embodiments, there may be one or more battery modules 30 , and multiple battery modules 30 are disposed in the box body, and the multiple battery modules 30 are combined with the box body 20 to form a battery pack.

[0095] Optionally, the battery module 30 is composed of a plurality of battery cells 31 connected in series, in parallel, or in a combination of series and parallel. The battery pack is a product that is further packaged and integrated on the basis of the battery module.

[0096] The battery module 30 includes a plurality of battery cells 31. The plurality of battery cells 31 can be connected in series and / or in parallel through electrical connectors 32 to form an integral battery module 30. The modular design of the battery cells 31 facilitates replacement or maintenance of the battery cells 31 when any battery cell 31 fails (such as hardware failure, thermal runaway, etc.). The battery module 30 forms a power supply circuit with an external load through the total positive and total negative to supply power. The battery module 30 is a core component of the energy storage device 100 and is used for energy storage and power supply.

[0097] Optionally, the battery cell 31 is in a rectangular shape, and a plurality of battery cells 31 are arranged in a rectangular array. In this way, the plurality of battery cells 31 are arranged in a relatively compact manner, which is conducive to miniaturization of the energy storage device 100 .

[0098] Optionally, the battery cell 31 includes a battery housing 312, a battery cell 313 and an explosion-proof valve 311. The battery cell 313 is disposed in the battery housing 312, and the explosion-proof valve 311 is disposed in the battery housing 312. Specifically, the explosion-proof valve 311 is disposed on a surface of the battery housing 312 that is directly opposite to the bottom surface 111 of the box cover 11, so that the gas ejected from the explosion-proof valve 311 after depressurization can be directly ejected toward the corresponding temperature detection device 12.

[0099] In some embodiments, there may be one or more battery packs, one or more battery packs may form a battery cluster, and the energy storage device 100 may include one or more battery clusters.

[0100] In some embodiments, the energy storage device 100 may be an energy storage cabinet, which is a large device for storing electrical energy. One or more battery packs may be arranged in the energy storage cabinet, or one or more battery clusters may be arranged in the energy storage cabinet, and the energy storage cabinet may be equipped with a complete power conversion, monitoring, management and other systems.

[0101] Optionally, the explosion-proof valve 311 is located at the center of the surface of the battery housing 312 corresponding to the box cover 11. In this way, when the battery cell 31 has thermal runaway, the explosion-proof valve 311 disposed at the center is more conducive to pressure relief, thereby improving the timeliness of thermal runaway detection.

[0102] In some embodiments, the energy storage device 100 also includes a battery management system 50, which is used to obtain detection information from the temperature detection device 12. The battery management system 50 is configured to determine that the energy storage device 100 has a risk of thermal runaway when it is determined based on the detection information that the temperature of any battery cell 31 is greater than a preset temperature.

[0103] Specifically, taking the temperature detection device 12 as a thermal switch as an example, the detection information is the current collected by the information collector 14. The battery management system 50 can determine whether a thermal switch is disconnected based on whether the current is 0, thereby determining whether there is at least one battery cell 31 with a temperature greater than a preset temperature, and further determining whether the energy storage device 100 has a risk of thermal runaway.

[0104] For example, when the current is 0, it is determined that the energy storage device 100 has a risk of thermal runaway; when the current is not 0, it is determined that the energy storage device 100 has no risk of thermal runaway.

[0105] Taking the temperature detection device 12 as a temperature sensor as an example, the detection information is the temperature collected by the temperature detection device 12. The battery management system 50 can determine whether the battery cell 31 corresponding to the temperature detection device 12 is in thermal runaway based on whether the temperature collected by the temperature detection device 12 is greater than the preset temperature.

[0106] For example, when the temperature collected by any temperature detection device 12 is greater than a preset temperature, it is determined that the energy storage device 100 is at risk of thermal runaway, and the position of the battery cell 31 experiencing thermal runaway can be determined based on the position of the temperature detection device 12 whose temperature is greater than the preset temperature; when the temperatures collected by all temperature detection devices 12 are less than or equal to the preset temperature, it is determined that the energy storage device 100 is not at risk of thermal runaway.

[0107] In some embodiments, the battery management system 50 is used to obtain detection information from the temperature detection device 12. The battery management system 50 is configured to generate thermal runaway information based on the detection information, and to determine whether to perform a thermal runaway management operation based on at least one of the thermal runaway information and the battery operation information. The thermal runaway management operation includes disconnecting the power supply circuit of the battery module 30 and issuing at least one of a thermal runaway prompt message.

[0108] Specifically, after the battery management system 50 determines the thermal runaway information (such as whether thermal runaway exists) based on the detection information collected by the temperature detection device 12, in order to improve the accuracy of the judgment of thermal runaway, it can also combine the battery operation information to make a comprehensive judgment. For example, in the case of determining that thermal runaway occurs based on the detection information, the temperature and voltage of the battery are obtained. When there is an abnormality in the battery operation information (battery temperature, voltage, current, etc.), it can be accurately determined that the battery module 30 has thermal runaway, so as to perform thermal runaway management operations.

[0109] Optionally, the thermal runaway management operation includes at least one of disconnecting the power supply circuit of the battery module 30 and issuing a thermal runaway prompt message. In this way, the degree of thermal runaway of the battery cell 31 that has thermal runaway can be slowed down by power off, and by issuing a thermal runaway prompt message, the user can deal with the battery cell 31 that has thermal runaway in time, thereby eliminating the thermal runaway problem, preventing the thermal runaway from spreading to other battery cells 31, and reducing losses.

[0110] See also Figure 6 The electric device 1000 of the embodiment of the present application includes the energy storage device 100 of any of the above embodiments, and the energy storage device 100 is used to provide electric energy for the electric device 100.

[0111] The power-consuming device 1000 refers to a device that consumes electric energy to realize various functions. For example, the power-consuming device may include but is not limited to: a mobile electronic device, an uninterruptible power supply (UPS) device, and the like.

[0112] In the description of this specification, the description with reference to the terms "certain embodiments", "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0113] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one feature. In the description of this application, the meaning of "plurality" is at least two, such as two, three, unless otherwise clearly and specifically defined.

[0114] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application. The scope of the present application is defined by the claims and their equivalents.

Claims

1. An energy storage device, characterized in that: The energy storage device comprises: Box; A battery module, the battery module is disposed in the box, and the battery module includes a plurality of battery cells; and A box cover assembly, the box cover assembly includes a box cover and a plurality of temperature detection devices, the box cover is arranged on the box body, the box body and the box cover form a receiving space, and the battery module is arranged in the receiving space; a plurality of temperature detection devices, a plurality of the temperature detection devices are arranged on the bottom surface of the box cover opposite to the box body, and the plurality of the temperature detection devices are respectively arranged opposite to the explosion-proof valves of the plurality of battery cells.

2. The energy storage device according to claim 1, characterized in that: The temperature detection device includes a bimetallic thermal switch or a thermistor thermal switch.

3. The energy storage device according to claim 2, characterized in that: The bimetallic thermal switch comprises a first metal member and a second metal member, wherein the first metal member and the second metal member have different thermal expansion coefficients, and the first metal member and the second metal member are disconnected when the temperature is greater than a preset temperature, and are connected when the temperature is less than the preset temperature.

4. The energy storage device according to claim 2, characterized in that: A plurality of the temperature detection devices are sequentially connected in series to form a detection loop. The detection loop further comprises a power supply and a signal collector. The signal collector is used to collect the current of the detection loop.

5. The energy storage device according to claim 4, characterized in that: The energy storage device also includes a battery management system, which is used to obtain the current collected by the signal collector. The battery management system is configured to determine that the energy storage device has a thermal runaway risk when the current is not zero.

6. The energy storage device according to claim 1, characterized in that: The temperature detection device comprises a temperature sensor, and the temperature detection sensor is used to detect the temperature of the area where the explosion-proof valve of the battery cell is located.

7. The energy storage device according to claim 2 or 6, characterized in that: The energy storage device also includes a battery management system, which is used to obtain detection information of the temperature detection device. The battery management system is configured to determine that the energy storage device has a risk of thermal runaway when it is determined based on the detection information that the temperature of any battery cell is greater than a preset temperature.

8. The energy storage device according to claim 3 or 7, characterized in that: The preset temperature is 80 degrees.

9. The energy storage device according to claim 1, characterized in that: The battery cells and the temperature detection devices are arranged in a one-to-one correspondence; or, a plurality of the battery cells are divided into a plurality of battery groups, and the temperature detection devices and the battery groups are arranged in a one-to-one correspondence.

10. The energy storage device according to claim 9, characterized in that: The temperature detection device and the corresponding explosion-proof valve of the battery cell are arranged opposite to each other.

11. The energy storage device according to claim 1, characterized in that: The distance between the temperature detection device and the corresponding explosion-proof valve of the battery cell is less than a preset distance.

12. The energy storage device according to claim 1, characterized in that: The size of the temperature detection device is determined based on the size of the corresponding explosion-proof valve of the battery cell.

13. The energy storage device according to claim 1, characterized in that: The battery cell comprises a battery core and a battery casing, and the explosion-proof valve is located at the center of the surface of the battery casing corresponding to the box cover.

14. The energy storage device according to claim 1, characterized in that: The energy storage device also includes a battery management system, which is used to obtain detection information from the temperature detection device. The battery management system is configured to generate thermal runaway information based on the detection information, and determine whether to perform a thermal runaway management operation based on at least one of the thermal runaway information and battery operation information. The thermal runaway management operation includes at least one of disconnecting the power supply circuit of the battery module and issuing a thermal runaway prompt message.

15. An electrical equipment, characterized in that: An energy storage device comprising any one of claims 1-14.

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