Fire extinguishing system suitable for liquid cooling energy storage of lithium ion battery

Abstract

The utility model provides a fire extinguishing system suitable for liquid cooling energy storage of a lithium ion battery, which belongs to the technical field of energy storage fire extinguishing, and comprises a battery module, a plurality of battery clusters, a plurality of lithium ion batteries, a plurality of lithium ion batteries, a plurality of lithium ion batteries, a plurality of lithium ion batteries, a plurality of lithium ion batteries and a plurality of lithium ion batteries, the battery management system is connected with the temperature detector and comprises a temperature comparison unit, a temperature rise comparison unit and a logic judgment unit, and the input end of the logic judgment unit is connected with the temperature comparison unit and the temperature rise comparison unit; the combustible gas detection modules are arranged outside the battery packs; and the master control module is respectively connected with the logic judgment unit, the combustible gas detection module, the alarm and the fire extinguishing device of the battery management system. The method has the beneficial effects that the thermal runaway state of the battery cell is comprehensively evaluated by monitoring the temperature and the temperature rise rate of the battery cell in the battery pack in real time and combining the combustible gas detection condition of the battery pack, so that early warning and rapid fire extinguishing are realized.

Description

TECHNICAL FIELD

[0001] The utility model relates to energy storage fire fighting technical field especially suitable for lithium ion battery liquid cooling energy storage's fire fighting system. BACKGROUND

[0002] With the rapid development of new energy technology, lithium ion battery liquid cooling energy storage products are widely used in industrial and commercial energy storage fields due to their high energy density, long cycle life and high safety performance. However, lithium ion batteries may cause temperature to rise sharply due to internal short circuit, thermal runaway and other reasons during charging and discharging cycles, which may cause fire. Due to the rapid nature of the chemical reaction inside the lithium battery, once the fire breaks out, it will spread rapidly in a short time, posing a serious threat to personnel safety, property safety and the environment.

[0003] The existing fire fighting system is usually composed of fire detection, fire line bundle, fire connector, piercing valve and fire nozzle and other accessories. The fire detector mainly relies on the combination of smoke temperature sensor and combustible gas detector (such as H2, CO detector).

[0004] If the combustible gas detector is set inside the battery pack, it is necessary to integrate a separate gas detector and the corresponding line connector in each battery pack, which will affect the size design of the battery pack and increase the integration cost. Moreover, the combustible gas detector usually uses electrochemical reagent for gas detection, which has a relatively short service life. Considering the sealing design of the battery pack, once the electrochemical reagent fails, the effectiveness of the detector will be greatly reduced due to the inability to disassemble the battery pack for replacement, thereby reducing the safety of the entire fire fighting system.

[0005] If the combustible gas detector is placed outside the battery pack, due to the sealing of the battery pack, the combustible gas can only be released to the outside to be captured by the detector when the shell is broken due to severe reaction inside the battery pack. However, at this time, the reaction inside the battery pack is usually out of control, and the fire risk rises sharply. The fire fighting system has missed the best opportunity to control the fire, and it is difficult to effectively contain the spread of the fire. SUMMARY

[0006] To solve the above technical problems, the utility model provides a fire fighting system suitable for lithium ion battery liquid cooling energy storage.

[0007] The technical problem solved by the utility model can be realized by the following technical solutions:

[0008] A fire fighting system suitable for lithium ion battery liquid cooling energy storage, comprising:

[0009] A battery module module, comprising a plurality of battery clusters, each of the battery clusters comprising a plurality of battery packs, each of the battery packs internally disposing a temperature detector;

[0010] A battery management system connected to the temperature detector, the battery management system comprising a temperature comparison unit, a temperature rise comparison unit and a logic judgment unit, input ends of the logic judgment unit being connected to the temperature comparison unit and the temperature rise comparison unit respectively;

[0011] A combustible gas detection module disposed externally to each of the battery packs;

[0012] A general control module connected to the logic judgment unit of the battery management system, the combustible gas detection module, an alarm and a fire extinguishing device.

[0013] Preferably, a first input end of the temperature comparison unit is connected to the temperature detector, a second input end of the temperature comparison unit is connected to a first signal, and an output end of the temperature comparison unit is connected to a first input end of the logic judgment unit.

[0014] Preferably, the first signal is a sum signal of a temperature deviation signal and a first preset value;

[0015] The temperature deviation signal is calculated by a temperature deviation calculation unit, the temperature deviation calculation unit comprising:

[0016] An average temperature calculation sub-unit, an input end of the average temperature calculation sub-unit being connected to the temperature detector;

[0017] A first deviation calculation sub-unit, a first input end of the first deviation calculation sub-unit being connected to an output end of the average temperature calculation sub-unit, a second input end of the first deviation calculation sub-unit being connected to a first preset reference temperature value, and an output end of the first deviation calculation sub-unit being used for outputting a temperature deviation signal.

[0018] Preferably, the temperature rise comparison unit comprises:

[0019] A temperature rise calculation sub-unit, an input end of the temperature rise calculation sub-unit being connected to the temperature detector;

[0020] A temperature rise comparison sub-unit, a first input end of the temperature rise comparison sub-unit being connected to the temperature rise calculation sub-unit, a second input end of the temperature rise comparison sub-unit being connected to a second signal, and an output end of the temperature rise comparison sub-unit being connected to a second input end of the logic judgment unit.

[0021] Preferably, the second signal is a sum signal of a temperature difference deviation signal and a second preset value;

[0022] The temperature difference deviation signal is calculated by a temperature difference deviation calculation unit, and the temperature difference deviation calculation unit comprises:

[0023] An average temperature difference calculation subunit, input ends of the average temperature difference calculation subunit being connected to the temperature detector and a second preset reference temperature value respectively;

[0024] A second deviation calculation subunit, a first input end of the second deviation calculation subunit being connected to an output end of the average temperature difference calculation subunit, a second input end of the second deviation calculation subunit being connected to a preset reference temperature difference value, and an output end of the second deviation calculation subunit being used for outputting a temperature difference deviation signal.

[0025] Preferably, the logic judgment unit comprises a logic AND operator.

[0026] Preferably, the combustible gas detection module is detachably arranged outside each battery pack.

[0027] Preferably, the combustible gas detection module comprises an air suction type fire-fighting host.

[0028] Preferably, the alarm comprises an audible and visual alarm.

[0029] Preferably, the fire extinguishing device comprises a fire suppression agent.

[0030] The technical scheme of the utility model has the advantages or beneficial effects that:

[0031] The fire-fighting system provided by the utility model, by being combined with the battery management system, realizes real-time monitoring of the temperature and temperature rise rate of the battery cell in the battery pack, in combination with the combustible gas detection condition of the battery pack, comprehensively evaluates the thermal runaway state of the battery cell, thereby realizing early warning and rapid fire extinguishing, and improving the coverage range of detection, the reliability of the system and the timeliness of response; at the same time, the combustible gas detection module is arranged outside the battery pack, so that the replacement of the electrochemical preparation becomes simple and feasible, the service life of the detector is further prolonged, and the continuous and effective operation of the fire-fighting system is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 For the preferred embodiment of the utility model, the structural block diagram of the fire-fighting system suitable for lithium ion battery liquid cooling energy storage is shown in the figure;

[0033] Figure 2 For the preferred embodiment of the utility model, the structural block diagram of the battery management system is shown in the figure. DETAILED DESCRIPTION

[0034] With reference to the drawings and specific embodiments, the present application will be further described, but not as a limitation of the present application.

[0035] It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict.

[0036] The present application will be further described below in combination with the drawings and specific embodiments, but not as a limitation of the present application.

[0037] Referring to Figure 1 In the preferred embodiments of the present application, based on the above problems existing in the prior art, a fire extinguishing system suitable for lithium ion battery liquid cooling energy storage is provided, comprising:

[0038] The battery module 1 comprises a plurality of battery clusters (BC1,..., BCN), and each battery cluster comprises a plurality of battery packs, and each battery pack is internally provided with a temperature detector.

[0039] The battery management system 3 (Battery Management System, BMS, hereinafter referred to as BMS system) is connected to the temperature detector, and the battery management system 3 comprises a temperature comparison unit 31, a temperature rise comparison unit 32 and a logic judgment unit 33, and the input end of the logic judgment unit 33 is connected to the temperature comparison unit 31 and the temperature rise comparison unit 32.

[0040] The combustible gas detection module 4 is arranged outside each battery pack.

[0041] The total control module 5 is connected to the logic judgment unit 33 of the battery management system 3, the combustible gas detection module 4, the alarm 6 and the fire extinguishing device 7.

[0042] Specifically, the battery module 1 is composed of a plurality of battery clusters (BC1,..., BCN), and each battery cluster contains a plurality of battery packs, for example, the first battery cluster BC1 comprises battery packs BP11, BP12,..., BP1n. Each battery pack is internally provided with a temperature detector, such as temperature detectors 21, 22,..., 2n corresponding to the battery packs in the first battery cluster BC1, for real-time monitoring and collecting the cell temperature of each battery pack.

[0043] The fire-fighting system provided by the embodiment of the utility model is composed of a fire detector, a battery management system 3, a general control module 5, an alarm 6 and a fire extinguishing device 7; wherein the fire detector comprises a temperature detector arranged inside the battery pack and a combustible gas detection module 4 arranged outside the battery pack.

[0044] The BMS system can receive the temperature detection data of each temperature detector, detect the cell temperature and temperature rise rate of the battery pack based on the temperature detection data, determine whether the cell monomer has thermal runaway, and feed back the real-time cell temperature value and thermal runaway determination result to the general control module 5.

[0045] The combustible gas detection module 4 can monitor the combustible gas concentration (such as H2 and CO) around the battery pack in real time, and feed back the real-time combustible gas detection value to the general control module 5.

[0046] The general control module 5 is responsible for receiving the real-time cell temperature value and thermal runaway determination result from the BMS system, and the real-time combustible gas detection value of the combustible gas detection module 4, making a comprehensive judgment, and then performing corresponding actions, such as issuing an alarm through the alarm 6 or starting the fire extinguishing device 7 to extinguish the fire.

[0047] The embodiment of the utility model combines the fire-fighting system with the battery management system 3, realizes real-time monitoring of the cell temperature and temperature rise rate in the battery pack, comprehensively evaluates the thermal runaway state of the cell in combination with the detection condition of the combustible gas in the battery pack, thereby realizing early warning and rapid fire extinguishing, and improving the coverage of detection, the reliability of the system and the timeliness of response.

[0048] Meanwhile, since the combustible gas detection module 4 is arranged outside the battery pack, the replacement of the electrochemical reagent becomes simple and feasible, further prolongs the service life of the detector, and ensures the continuous and effective operation of the fire-fighting system.

[0049] As a preferred embodiment, wherein, as shown in Figure 2 The first input end of the temperature comparison unit 31 is connected to the temperature detector, the second input end of the temperature comparison unit 31 is connected to the first signal, and the output end of the temperature comparison unit 31 is connected to the first input end of the logic judgment unit 33.

[0050] Specifically, in the embodiment, the first input end of the temperature comparison unit 31 is directly connected to the output end of the temperature detector, and the cell temperature value detected by the temperature detector is received and captured in real time; the second input end is connected to the first signal, and the first signal is the temperature threshold value, which is used as the reference for judging the temperature state. By comparing the real-time detected cell temperature value with the temperature threshold value, a first comparison result is output. The first comparison result indicates whether the current cell temperature value is higher, lower or equal to the temperature threshold value, and then the subsequent corresponding logic judgment operation is performed.

[0051] Further, the first signal can be a preset fixed value, which is set according to needs.

[0052] Further, the first signal can also be a variable value. As a preferred embodiment, the first signal is the sum of the temperature deviation signal Δt and the first preset value t1, i.e. Δt+t1.

[0053] The temperature deviation signal Δt is calculated by the temperature deviation calculation unit 34, which comprises:

[0054] The average temperature calculation sub-unit 341, the input end of which is connected to the temperature detector;

[0055] The first deviation calculation sub-unit 342, the first input end of which is connected to the output end of the average temperature calculation sub-unit 341, the second input end of which is connected to the first preset reference temperature value Tref1, and the output end of which is used to output the temperature deviation signal Δt.

[0056] Specifically, in the present embodiment, the battery cell temperature is summarized and counted based on the temperature detection data, and the average temperature value of the battery cell detected in a continuous period of time is calculated by the average temperature calculation sub-unit 341, which is then transmitted to the first input end of the first deviation calculation sub-unit 342.

[0057] The second input end of the first deviation calculation sub-unit 342 is connected to a source storing the first preset reference temperature value Tref1, which is used to compare with the average value received from the average temperature calculation sub-unit 341. By performing subtraction operation, the first deviation calculation sub-unit 342 calculates the difference between the two, i.e. the temperature deviation signal Δt.

[0058] Then, the temperature deviation signal Δt is added to the first preset value t1 to obtain the final first signal, which is the temperature threshold mentioned above.

[0059] In the present embodiment, the first preset value t1 is a preset fixed value. As an example but not limitation, the first preset value t1 is preferably 56 degrees.

[0060] As a preferred embodiment, the temperature rise comparison unit 32 comprises:

[0061] The temperature rise calculation sub-unit 321, the input end of which is connected to the temperature detector;

[0062] The temperature rise comparison subunit 322 has a first input end connected to the output end of the temperature rise calculation subunit 321, a second input end connected to the second signal, and an output end connected to the second input end of the logic judgment unit 33.

[0063] Specifically, in the present embodiment, the temperature rise calculation subunit 321 is configured to receive the temperature detection data in a preset time period and calculate the temperature variation, i.e. the temperature rise value. The calculated temperature rise value is then transmitted to the first input end of the temperature rise comparison subunit 322. The second input end of the temperature rise comparison subunit 322 receives a second signal from outside or inside the system, i.e. the temperature rise threshold, as a reference for judging the temperature rise rate state. By comparing the received temperature rise value with the second signal, a second comparison result is output. The second comparison result indicates whether the temperature rise value in the preset time period is higher, lower or equal to the temperature rise threshold, and then performs the subsequent corresponding logic judgment operation.

[0064] Further, the second signal can be a preset fixed value, which can be set as needed.

[0065] Further, the second signal can also be a variable value. As a preferred embodiment, the second signal is the sum signal of the temperature difference deviation signal Δk and the second preset value k1, i.e. Δk+k1.

[0066] The temperature difference deviation signal Δk is calculated by the temperature difference deviation calculation unit 35, which includes:

[0067] The average temperature difference calculation subunit 351 has input ends connected to the temperature detector and the second preset reference temperature value Tref2, respectively.

[0068] The second deviation calculation subunit 352 has a first input end connected to the output end of the average temperature difference calculation subunit 351, a second input end connected to the preset reference temperature difference value ΔTref, and an output end for outputting the temperature difference deviation signal Δk.

[0069] Specifically, in this embodiment, the input end of the average temperature difference calculation subunit 351 simultaneously receives the battery cell temperature in the preset time period from the temperature detector and the second preset reference temperature value Tref2, obtains the average temperature difference in a period of time by calculating the difference between the two, and outputs the result to the first input end of the second deviation calculation subunit 352. The second input end of the second deviation calculation subunit 352 is connected to a source storing the preset reference temperature difference value ΔTref, for comparison with the average temperature difference received from the average temperature difference calculation subunit 351. By performing a subtraction operation, the second deviation calculation subunit 352 calculates the difference between the two, i.e., the temperature difference deviation signal Δk.

[0070] In this embodiment, the second preset value k1 is a preset fixed value. As an example but not limitation, the second preset value k1 is preferably 9 degrees.

[0071] Further, in this embodiment, the BMS system determines whether the temperature rise in the preset time period is greater than Δk+k1 and whether the battery cell temperature is greater than Δt+t1 based on the temperature detection data, and determines whether the battery cell monomer has thermal runaway by the above two determination conditions.

[0072] When the two determination conditions are met at the same time, i.e., the temperature rise in the preset time period is greater than Δk+k1 and the battery cell temperature is greater than Δt+t1, it is determined that the thermal runaway determination condition is met, and the BMS feeds back the real-time battery cell temperature value and the thermal runaway determination result to the total control module 5.

[0073] In this embodiment, the preset time period can be set as needed. As an example but not limitation, the preset time period is 3 minutes.

[0074] Further, considering that there are differences in the operation conditions of lithium ion battery liquid-cooled energy storage products at various project sites, the BMS system sets the first signal (i.e., the temperature threshold) and the second signal (i.e., the temperature rise threshold) based on statistical historical temperature detection data as a reference. In this embodiment, the BMS system can also include a storage unit for storing historical temperature detection data, and the input ends of the above-mentioned average temperature calculation subunit 341 and average temperature difference calculation subunit 351 can be directly connected to the storage unit. Based on the historical temperature detection data, the first signal and the second signal that adapt to the unique battery cell maximum temperature and temperature rise rate determination basis of the project are obtained. Compared with the fixed value used in the prior art for temperature and temperature rise judgment, the present utility model scheme is based on the product site operation condition, and the thermal runaway state judgment basis is more objective and reasonable.

[0075] In the control process of the fire extinguishing system, the battery cell thermal runaway state is comprehensively judged in combination with the real-time maximum battery cell temperature and temperature rise rate data, and is fed back to the total control module 5. The total control module 5 combines the flammable gas condition of the battery pack to improve the detection range, reliability, and timeliness.

[0076] As a preferred embodiment, the logic judging unit 33 comprises a logic AND operator.

[0077] Specifically, in the embodiment, the logic judging unit 33 adopts a logic AND operator to comprehensively judge whether the battery cell has thermal runaway in combination with the results of the temperature comparison and the temperature rise comparison. If both conditions are met, it is determined that thermal runaway has occurred, and the result is fed back to the general control module 5.

[0078] As a preferred embodiment, the combustible gas detection module 4 is detachably arranged outside each battery pack.

[0079] As a preferred embodiment, the combustible gas detection module 4 comprises an air suction type fire-fighting host.

[0080] Specifically, in the embodiment, an air suction type fire-fighting host is used as a detection device for combustible gas in the battery pack. The device forcibly sucks in the gas in the battery pack and analyzes the combustible substances in the gas to make a safety judgment of the battery pack.

[0081] The air suction type fire-fighting host is arranged outside the battery pack and is arranged in a part of the industrial and commercial lithium ion battery liquid-cooled energy storage product that is easy to detach. When the H2 and CO detection agent reaches the service life, the air suction type fire-fighting host only needs to be detached, and the detection agent thereof can be replaced.

[0082] By integrating the replaceable air suction type fire-fighting host, the H2 and CO detection agent can be effectively replaced, the service life of the fire-fighting system is prolonged, and the safety of long-term operation of the system is increased. At the same time, it is not necessary to separately install the combustible gas detection module 4 for each battery pack, the use of fire-fighting components and connection harnesses is reduced, and the cost is reduced.

[0083] Further, for the existing fire-fighting system, a false alarm is easily caused by too low combustible gas warning threshold, unnecessary maintenance cost is increased, or the initial warning of fire is missed by too high threshold, and a safety hazard is caused. In the embodiment, the air suction type fire-fighting host is provided with multiple thresholds, such as a warning threshold, a first alarm threshold, and a second fire-fighting trigger threshold, to ensure different levels of safety response.

[0084] As a preferred embodiment, the alarm 6 comprises an audible and visual alarm.

[0085] As a preferred embodiment, the fire extinguishing device 7 comprises a fire suppression agent.

[0086] In the embodiment, the system of the utility model can automatically trigger the audible and visual alarm when the warning is triggered, and trigger the fire extinguishing device 7 when thermal runaway occurs through the communication interface, so that the human operation delay is greatly reduced, and the response speed is improved.

[0087] In this embodiment, a standardized communication protocol such as Modbus, CAN bus, etc. is used to ensure that the BMS system can effectively communicate with the existing fire protection system, so that the system can quickly and effectively coordinate various resources and response measures in an emergency.

[0088] In the above preferred embodiment, the working process of the fire protection system of the utility model is as follows:

[0089] First, the temperature probe in the battery pack collects the cell temperature in real time to obtain temperature detection data;

[0090] Then, based on the historical temperature detection data, the average temperature value and the average temperature difference value of each cell are obtained by statistics, and the temperature deviation signal At of the average temperature value and the first preset reference temperature value Tref1 is calculated, and the temperature difference deviation signal Ak of the average temperature difference value and the preset reference temperature difference value ATref is calculated;

[0091] Next, the BMS system summarizes the temperature detection data collected in real time, and determines whether the cell monomer has thermal runaway based on whether the temperature rise in the preset time period is greater than Ak+k1 and whether the real-time cell temperature is greater than At+t1. When both conditions are met, i.e. the thermal runaway determination condition is met, the BMS system feeds back the real-time value and the thermal runaway determination result to the general control module 5;

[0092] At the same time of temperature detection, the air suction type fire host monitors the amount of combustible gas and feeds back the real-time value to the general control module 5.

[0093] When the real-time value of the combustible gas exceeds the early warning threshold value, and at the same time does not exceed the first level alarm threshold value, the general control module 5 judges whether to trigger the sound and light alarm according to the thermal runaway determination result provided by the BMS system.

[0094] When the BMS system simultaneously determines that the thermal runaway is triggered, the general control module 5 outputs the action signal to the sound and light alarm, and records this alarm at the same time.

[0095] When the real-time value of the combustible gas exceeds the first level alarm threshold value, the air suction type fire host controls the triggering of the sound and light alarm and the fire suppression agent of the fire extinguishing device 7.

[0096] The fire protection system provided in the embodiment of the utility model, through the thermal runaway determination based on the real-time monitoring of the cell temperature and the temperature rise rate integrated in the battery management system (BMS), combined with the high sensitivity detection of the combustible gas of the air suction type fire host, early fire warning is carried out, which can timely find fire hazards, rapidly reduce the system temperature through the fire suppression agent in the early stage of fire, delay the spread of fire, and improve the fire extinguishing efficiency.

[0097] It should be noted that the utility model aims at the problem of early fire control to meet the actual application demand, the utility model belongs to the data processing ability and hardware control ability of BMS system and general control module are adopted, through the combination mode, the industrial innovation is carried out, the utility model does not involve any innovation of software, the transmission mode or control mode between temperature detector, suction type fire host computer, BMS system, general control module and fire extinguishing device, although it cannot be separated from software code, but these software codes belong to prior art, the technical personnel in the art only need to cut or transplant the existing code to the utility model, of course, can also write according to product technical document, therefore, the utility model wants to protect is the hardware connection relationship, and does not involve the innovation of software.The above-mentioned embodiments and preferred embodiments are understood as such.

[0098] The advantages or beneficial effects of the above technical solutions are that: the fire-fighting system proposed by the utility model realizes real-time monitoring of the temperature and temperature rise rate of the battery cell in the battery pack by combining with the battery management system, comprehensively evaluates the thermal runaway state of the battery cell in combination with the combustible gas detection condition of the battery pack, thereby realizes early warning and rapid fire extinguishing, improves the coverage range of detection, the reliability of the system and the timeliness of response, and at the same time, the combustible gas detection module is externally arranged outside the battery pack, so that the replacement of the electrochemical preparation becomes simple and feasible, further prolongs the service life of the detector, and ensures the continuous and effective operation of the fire-fighting system.

[0099] The above is only the preferred embodiment of the utility model, and does not limit the implementation and protection scope of the utility model, and for those skilled in the art, it should be realized that any equivalent replacement and obvious change obtained by applying the contents of the specification and drawings should be included in the protection scope of the utility model.

Claims

1. A fire extinguishing system suitable for lithium ion battery liquid cooling energy storage, characterized in that, The application relates to a battery module, which comprises a battery module module, a battery management system, a combustible gas detection module and a total control module. The battery module module comprises a plurality of battery clusters, each of which comprises a plurality of battery packs, and each of the battery packs is internally provided with a temperature detector. The battery management system is connected with the temperature detector, and comprises a temperature comparison unit, a temperature rise comparison unit and a logic judgment unit. The combustible gas detection module is arranged outside each of the battery packs. The total control module is connected with the logic judgment unit of the battery management system, the combustible gas detection module, an alarm and a fire extinguishing device.

2. The fire extinguishing system suitable for liquid-cooled energy storage of lithium-ion batteries according to claim 1, characterized in that, The first input end of the temperature comparison unit is connected with the temperature detector, the second input end of the temperature comparison unit is connected with a first signal, and the output end of the temperature comparison unit is connected with the first input end of the logic judgment unit.

3. The fire extinguishing system suitable for liquid-cooled energy storage of lithium-ion batteries according to claim 2, characterized in that, The first signal is an addition signal of a temperature deviation signal and a first preset value. The temperature deviation signal is calculated by a temperature deviation calculation unit, and the temperature deviation calculation unit comprises an average temperature calculation subunit, a first deviation calculation subunit and a second deviation calculation subunit. The input end of the average temperature calculation subunit is connected with the temperature detector. The first input end of the first deviation calculation subunit is connected with the output end of the average temperature calculation subunit, the second input end of the first deviation calculation subunit is connected with a first preset reference temperature value, and the output end of the first deviation calculation subunit is used for outputting the temperature deviation signal.

4. The fire extinguishing system suitable for liquid-cooled energy storage of lithium-ion batteries according to claim 1, characterized in that, The temperature rise comparison unit comprises a temperature rise calculation subunit and a temperature rise comparison subunit. The input end of the temperature rise calculation subunit is connected with the temperature detector. The first input end of the temperature rise comparison subunit is connected with the temperature rise calculation subunit, the second input end of the temperature rise comparison subunit is connected with a second signal, and the output end of the temperature rise comparison subunit is connected with the second input end of the logic judgment unit.

5. The fire extinguishing system suitable for liquid-cooled energy storage of lithium-ion batteries according to claim 4, characterized in that, The second signal is an addition signal of a temperature difference deviation signal and a second preset value. The temperature difference deviation signal is calculated by a temperature difference deviation calculation unit, and the temperature difference deviation calculation unit comprises an average temperature difference calculation subunit, a second deviation calculation subunit and a third deviation calculation subunit. The input end of the average temperature difference calculation subunit is connected with the temperature detector and a second preset reference temperature value. The first input end of the second deviation calculation subunit is connected with the output end of the average temperature difference calculation subunit, the second input end of the second deviation calculation subunit is connected with a preset reference temperature difference value, and the output end of the second deviation calculation subunit is used for outputting the temperature difference deviation signal.

6. The fire extinguishing system suitable for liquid-cooled energy storage of lithium-ion batteries according to claim 1, characterized in that, The logic judgment unit comprises a logic and operator.

7. The fire extinguishing system suitable for liquid-cooled energy storage of lithium-ion batteries according to claim 1, characterized in that, The combustible gas detection module is detachably arranged outside each of the battery packs.

8. The fire extinguishing system suitable for liquid-cooled energy storage of lithium-ion batteries according to claim 1, characterized in that, The combustible gas detection module comprises an air suction type fire control host.

9. The fire extinguishing system suitable for liquid-cooled energy storage of lithium-ion batteries according to claim 1, characterized in that, The alarm comprises an audible and visual alarm.

10. The fire extinguishing system suitable for liquid-cooled energy storage of lithium-ion batteries according to claim 1, characterized in that, The fire extinguishing device comprises a fire control inhibitor.

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