Fire control method and fire control system

Abstract

The invention discloses a fire control method. The method comprises the following steps: S1, respectively acquiring a battery pack state parameter of a battery pack at a first time point and a battery pack state parameter of the battery pack at a second time point; s2, judging whether the battery pack state parameter of the battery pack at the first time point and the battery pack state parameter of the battery pack at the second time point meet a primary preset condition relationship or not; if yes, entering the step S3; s3, judging whether the battery pack state parameter of the battery pack at the first time point and the battery pack state parameter of the battery pack at the second time point meet a secondary preset condition relationship or not; if so, entering step S4; and S4, disconnecting charging and discharging loops of all the battery cells in the battery pack. The corresponding fire-fighting action is executed for the thermal runaway stage of the battery pack, and fire-fighting judgment and processing are facilitated. Correspondingly, the invention further discloses a fire control system which is used for executing the fire control method.

Description

[0001] This case is a divisional application based on the invention patent with application date of September 29, 2024, application number: 2024113652261, and name: "A fire control method and fire control system for an energy storage box". Technical Field

[0002] The present invention relates to the field of energy storage technology, and in particular to a fire control method and a fire control system. Background Art

[0003] With the development of energy storage technology, energy storage boxes are being used more and more widely. However, the charge and discharge cycle life and safety of the cells in the energy storage box are greatly affected by temperature. When the cell temperature is too high or the temperature difference is large, the cell cycle life will drop significantly, affecting the service life of the energy storage product. In severe cases, it will cause thermal runaway of the cell, and even cause explosion or fire.

[0004] Therefore, in the prior art, the energy storage box receives information from the detector through the battery management system to determine whether the temperature of the battery cluster is too high and whether there is a fire in the container. However, before the fire occurs in the energy storage box, there is a thermal runaway stage of the battery pack. Due to the high hysteresis problem of the existing fire control method of the energy storage box, it is impossible to perform corresponding fire fighting actions for the thermal runaway stage of the battery pack. It does not start to cool down and extinguish the energy storage box until heat spreads or diffuses inside the energy storage box, which makes it easy to damage the energy storage elements of the energy storage box and has low reliability. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a fire control method to solve the problem of high hysteresis and low reliability of the fire monitoring and judgment mode of the traditional fire control method.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a fire control method, which comprises the following steps:

[0007] S1: respectively obtaining a battery pack state parameter of a battery pack at a first time point and a battery pack state parameter of the battery pack at a second time point, wherein the first time point is a moment after the second time point; wherein the battery pack state parameter includes an air pressure inside the battery pack and a combustible gas concentration inside the battery pack;

[0008] S2: Determine whether the battery pack state parameter of the battery pack at the first time point and the battery pack state parameter of the battery pack at the second time point satisfy a preset condition relationship; if so, proceed to step S3; if not, repeat steps S1 to S2;

[0009] S3: Determine whether the battery pack state parameter of the battery pack at the first time point and the battery pack state parameter of the battery pack at the second time point meet the secondary preset condition relationship; if so, proceed to step S4; if not, repeat steps S1 to S2;

[0010] S4: disconnecting the charge and discharge circuits of all cells in the battery pack;

[0011] The primary preset condition relationship includes simultaneously satisfying the following conditions:

[0012]

[0013] Among them, t b3 is the first time point, P b3 is the gas pressure inside the battery pack at the first time point, X b3 is the combustible gas concentration inside the battery pack at the first time point, t b4 is the second time point, P b4 is the gas pressure inside the battery pack at the second time point, X b4 is the combustible gas concentration inside the battery pack at the second time point, VP 34 VX is the preset pressure change rate. 34 To preset the rate of change of the combustible gas concentration;

[0014] The secondary preset condition relationship includes satisfying at least one of the following conditions:

[0015] P b4 ≥P c

[0016] X b4 ≥X c

[0017] Among them, P c is the preset maximum air pressure, X c It is the preset maximum combustible gas concentration.

[0018] Furthermore, in the fire control method described in the present invention, in step S4, the following step is also included: a fire pipe sprays a fire-fighting agent to the battery pack.

[0019] Furthermore, in the fire control method of the present invention, in step S4, the following step is also included: releasing inert gas inside the container.

[0020] Furthermore, in the fire control method of the present invention, in step S4, the following step is also included: when the oxygen concentration inside the container is lower than a preset concentration, the injection of inert gas into the container is stopped.

[0021] Furthermore, in the fire control method described in the present invention, after step S4, it also includes step S5: respectively obtaining the cell status parameters of all the battery cells in the battery pack; when the cell status parameters of two adjacent battery cells both meet the cell thermal runaway conditions, the first operating state meets the heat spread conditions, and the liquid cooling mechanism cools the battery cluster to which the battery pack belongs.

[0022] Furthermore, in the fire control method described in the present invention, after step S5, step S6 is also included: obtaining fire information inside the container, when a flame appears in the container, the second operating state satisfies the heat diffusion condition; the nozzle sprays the fire extinguishing agent to the battery cluster to extinguish the flame; when the nozzle completes spraying the fire extinguishing agent and the flame is not extinguished, the water filling mechanism fills water into the box body of the energy storage box.

[0023] Another object of the present invention is to provide a fire control system, wherein the fire energy storage system includes an energy storage box, the energy storage box includes a container and a plurality of battery clusters arranged in the container, the battery cluster includes a plurality of battery packs, and the battery pack includes a plurality of battery cells. It is characterized in that the fire control system is used for the fire control method as described above, including a battery pack fire protection module for performing fire control on the battery pack.

[0024] Furthermore, in the fire control system described in the present invention, the battery pack fire protection module includes an air pressure sensor, a combustible gas sensor, a fire protection pipe, an inert gas injection pipe and an oxygen concentration detection device, the air pressure sensor and the combustible gas sensor are both arranged in the battery pack, the container is provided with a pressure relief port, the oxygen concentration detection device is arranged in the pressure relief port, the fire protection pipe is arranged in the container, the battery pack is provided with a connecting port, and the fire protection pipe is connected to the connecting port.

[0025] Furthermore, in the fire control system described in the present invention, it also includes a battery cell fire protection module for performing fire control on the battery cell, and the battery cell fire protection module includes a deformation detector, a temperature detector and a voltage detector. The deformation detector is arranged on the explosion-proof valve of the battery cell, and the temperature detector and the voltage detector are respectively arranged on the two electrode columns of the battery cell.

[0026] Furthermore, in the fire control system described in the present invention, it also includes a container fire protection module for performing fire control on the container, and the container fire protection module includes a water filling mechanism, a camera and a sprinkler, wherein the camera and the sprinkler are both arranged in the container, and the water filling mechanism is connected to the water filling inlet in the container.

[0027] The beneficial effect of the present invention is that the fire control method provided by the present invention can set corresponding fire judgment conditions and fire strategies for the battery pack of the energy storage box to ensure that the energy storage box can execute the corresponding fire strategy in time when the battery pack is thermally runaway, thereby reducing the possibility of fire in the container, reducing damage to the energy storage components, and improving the reliability of the energy storage box. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A flow chart of the fire control method of the present invention;

[0029] Figure 2 Another flow chart of the fire control method of the present invention;

[0030] Figure 3 The structure diagram of the battery core of the energy storage box of the fire control system provided by the present invention is schematically shown;

[0031] Figure 4 The battery pack structure diagram of the energy storage box of the fire control system provided by the present invention is schematically shown;

[0032] Figure 5 Schematically shows Figure 4 A plurality of battery cells arranged adjacent to each other in a battery pack;

[0033] Figure 6 The structure diagram of a container using an energy storage box of the fire control system provided by the present invention is schematically shown at one viewing angle;

[0034] Figure 7 The structure of a container using an energy storage box of the fire control system provided by the present invention is schematically shown from another perspective.

[0035] Description of labels:

[0036] 1. Battery cell; 2. Battery cell pole; 3. Battery cell explosion relief valve; 4. Deformation detector; 5. Temperature detector; 6. Voltage detector; 7. Battery pack; 8. Air pressure sensor and combustible gas sensor; 9. Fire protection pipe; 10. Inert gas injection pipe; 11. Oxygen concentration detection device; 12. Container; 13. Pressure relief port; 14. Connection port; 15. Water inlet; 16. Liquid cooling pipeline; 17. Liquid cooling valve; 18. Camera; 19. Nozzle; 20. Water immersion sensor; 21. Battery cluster; 22. Pipeline valve. DETAILED DESCRIPTION

[0037] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in conjunction with the implementation modes and the accompanying drawings.

[0038] Reference Figures 3 to 7The energy storage box is provided with energy storage elements according to the following architecture: a plurality of battery clusters 21 are provided in the container 12 , a plurality of battery packs 7 are provided in the battery clusters 21 , and a plurality of battery cells 1 are provided in the battery packs 7 .

[0039] In the traditional fire control system of the energy storage box, the battery management system receives the information fed back by the detector to judge the internal state of the container 12, and directly uses water to extinguish the fire when a fire is detected inside the container 12. However, before the fire occurs in the energy storage box, there are the thermal runaway stage of the battery cell 1, the thermal runaway stage of the battery pack 7, and the thermal spread stage of the battery pack 7; the heat released by the thermal runaway of a single battery cell 1 is limited and will not cause too serious harm, but the thermal runaway of the battery cell 1 or battery pack 7 will quickly spread to the surrounding battery cells 1 or battery pack 7, and the adjacent battery cells 1 or battery pack 7 will successively transfer the heat generated by the thermal runaway, and also experience thermal runaway, triggering a "domino effect" and causing the energy storage box to enter the thermal diffusion stage.

[0040] The fire management system of the traditional energy storage box simply cools the battery cluster 21 through a liquid cooling mechanism and extinguishes the fire in the container 12 through a water filling system. The fire control method of the traditional energy storage box has a high lag and cannot perform corresponding firefighting actions for the thermal runaway stage of the battery cell 1 or the thermal runaway stage of the battery pack 7. The reliability of this traditional fire control method is low. The energy storage box is not cooled or extinguished until heat spreads or diffuses inside the energy storage box, which easily damages the energy storage elements of the energy storage box.

[0041] To solve this problem, please refer to Figure 1 as well as Figure 2 This embodiment designs a fire control method for an energy storage box, which includes the following steps:

[0042] Obtaining a cell state parameter of the cell, and when the cell state parameter meets the cell thermal runaway condition, executing a first-level fire fighting strategy; wherein the cell state parameter includes a cell temperature of the cell, a cell voltage of the cell, and a deformation amount of an explosion relief valve of the cell (this step is step S0);

[0043] Obtaining a battery pack status parameter of the battery pack to which the battery cell belongs, and executing a secondary firefighting strategy when the battery pack status parameter meets a battery pack thermal runaway condition; wherein the battery pack status parameter includes the gas pressure inside the battery pack and the combustible gas concentration inside the battery pack;

[0044] Acquire a first operating state of the battery pack, and when the first operating state meets a heat spread condition, execute a three-level fire protection strategy (this step is step S5);

[0045] The second operating state of the container to which the battery pack belongs is obtained, and when the second operating state meets the heat diffusion condition, the fourth-level fire protection strategy is executed (this step is step S6).

[0046] The fire control method provided in the present invention sets four levels of fire monitoring conditions in sequence according to the order in which the energy storage elements in the energy storage box induce thermal runaway, and can respectively execute four levels of fire strategies according to the four fire monitoring conditions.

[0047] In order to implement the above-mentioned fire control method, the present invention also designs a fire control system for an energy storage box, which includes a battery cell fire control module for performing fire control on the battery cell 1, a battery pack fire control module for performing fire control on the battery pack 7, a battery cluster fire control module for performing fire control on the battery cluster 21, and a container fire control module for performing fire control on the container 12.

[0048] Thermal runaway of battery cell 1 is usually caused by two reasons: internal short circuit and strong redox reaction between positive electrode material and electrolyte. Therefore, when thermal runaway occurs in battery cell 1, the voltage of battery cell 1 will drop sharply, the temperature of battery cell 1 will rise sharply, and the explosion-proof valve of battery cell 1 will be deformed.

[0049] Please refer to Figure 3 The battery cell fire protection module of the fire control system provided in the embodiment is designed for the above-mentioned characteristics of thermal runaway of the battery cell 1, and includes: a deformation detector 4, a temperature detector 5 and a voltage detector 6. The deformation detector 4 is arranged on the explosion-proof valve of the battery cell 1, and the temperature detector 5 and the voltage detector 6 are respectively arranged on the two electrode columns 2 of the battery cell 1. The temperature detector 5 is used to obtain the temperature of the battery cell 1, the voltage detector 6 is used to obtain the voltage of the battery cell 1, and the deformation detector is used to obtain the deformation of the explosion-proof valve. Therefore, in step S0 of the fire control method provided in this embodiment, the battery cell state parameters of the battery cell 1 include: the temperature of the battery cell 1, the voltage of the battery cell 1 and the deformation of the explosion-proof valve.

[0050] In this embodiment, step S0 includes: obtaining a cell state parameter of the cell, and when the cell state parameter meets the cell thermal runaway condition, executing a first-level fire fighting strategy, which specifically includes the following steps:

[0051] S01: respectively obtaining a cell state parameter of the cell at a first moment and a cell state parameter of the cell at a second moment, wherein the second moment is a moment after the first moment;

[0052] S02: Determine whether the cell state parameter of the cell at the first moment and the battery pack state parameter of the cell at the second moment meet a first preset condition; if so, proceed to step S03; if not, repeat steps S01 to S02;

[0053] S03: Determine whether the cell state parameter of the cell at the first moment and the battery pack state parameter of the cell at the second moment meet a second preset condition; if so, proceed to step S04; if not, repeat steps S01 to S02;

[0054] S04: disconnecting the charging and discharging circuit of the battery cell.

[0055] In detail, the first precondition mentioned above includes satisfying the following conditions at the same time:

[0056]

[0057] Among them, t b1 is the first moment, T b1 is the cell temperature of the cell at the first moment, V b1 is the cell voltage of the cell at the first moment, S b1 is the deformation amount of the battery cell explosion relief valve 3 of the battery cell at the first moment, t b2 is the second moment, T b2 is the cell temperature of the cell at the second moment, V b2 is the cell voltage of the cell at the second moment, S b2 is the deformation amount of the battery cell explosion relief valve 3 at the second moment, VT 12 is the preset temperature change rate, VV 12 is the preset voltage change rate, VS 12 is the preset deformation rate;

[0058] The second preset condition includes satisfying at least one of the following conditions:

[0059] T b2 ≥T c

[0060] V b2 ≥V c

[0061] Among them, T c is the preset maximum temperature of the battery cell, V c It is the preset minimum voltage of the battery cell.

[0062] In this embodiment, the first-level fire protection strategy is to disconnect the charging and discharging circuit of the battery cell with thermal runaway.

[0063] When the temperature change rate, voltage change rate and deformation change rate of the battery cell explosion relief valve 3 exceed the preset temperature change rate, voltage change rate and deformation change rate respectively, it can be judged that the battery cell may be in thermal runaway. However, in order to prevent misjudgment and affect the reliability of the energy storage box using the fire control method, when only the first preset condition is met and the second preset condition is not met, the first-level fire strategy is not executed, but steps S01 to S02 are repeatedly executed until the battery cell state parameters at the first moment and the battery cell state parameters at the second moment simultaneously meet the first preset condition and the second preset condition, and then the first-level fire strategy is executed.

[0064] Preferably, after step S04, step S05 is also included: repeating step S01 to determine whether the battery cell state parameters at the first moment and the battery cell state parameters at the second moment do not satisfy the first preset condition and the second preset condition at the same time; if so, restoring the charge and discharge circuit of the battery cell; if not, repeating step S05 until the battery cell state parameters at the first moment and the battery cell state parameters at the second moment do not satisfy the first preset condition and the second preset condition at the same time.

[0065] When a battery cell experiences thermal runaway, it may cause the internal gas pressure of the battery pack to which it belongs to increase, and generate flammable gas inside the battery pack. When the internal gas pressure of the battery pack is too high and the concentration of flammable gas is too high, it may cause thermal runaway of the battery pack. To this end, this embodiment further provides the following steps to address the above problems: obtaining the battery pack status parameters of the battery pack to which the battery cell belongs, and executing the secondary fire protection strategy when the battery pack status parameters meet the battery pack thermal runaway conditions.

[0066] Please refer to Figure 4 The battery pack fire protection module of the fire control system provided in this embodiment is designed for the characteristics of thermal runaway of the battery pack 7, and the battery pack fire protection module includes: an air pressure sensor and a combustible gas sensor 8, both of which are arranged in the battery pack 7 to obtain the air pressure and combustible gas concentration inside the battery pack 7, respectively. Therefore, in the steps of the fire control method provided in this embodiment, the battery pack state parameters of the battery pack 7 include: the air pressure and combustible gas concentration inside the battery cell 1.

[0067] Also, please refer to Figure 6 In order to prevent the explosion caused by flames due to thermal runaway of the battery pack 7, in this embodiment, the battery pack fire protection module also includes: a fire protection pipe 9, an inert gas injection pipe 10 and an oxygen concentration detection device 11. A pressure relief port 13 is provided on the container 12. The oxygen concentration detection device 11 is arranged in the pressure relief port 13. The fire protection pipe 9 is arranged in the container 12. A connecting port 14 is provided on the battery pack 7. The fire protection pipe 9 is connected to the connecting port 14. The fire protection pipe 9 is used to release a fire extinguishing agent into the battery pack 7. The fire extinguishing agent can be a gaseous agent or a liquid agent.

[0068] In the fire control method provided in this embodiment, the above step of obtaining the battery pack status parameters of the battery pack to which the battery cell belongs, and executing the secondary fire strategy when the battery pack status parameters meet the battery pack thermal runaway condition, specifically includes the following steps:

[0069] S1: respectively obtaining a battery pack state parameter of a battery pack at a first time point and a battery pack state parameter of the battery pack at a second time point, wherein the first time point is a moment after the second time point;

[0070] S2: Determine whether the battery pack state parameter of the battery pack at the first time point and the battery pack state parameter of the battery pack at the second time point satisfy a preset condition relationship; if so, proceed to step S3; if not, repeat steps S1 to S2;

[0071] S3: Determine whether the battery pack state parameter of the battery pack at the first time point and the battery pack state parameter of the battery pack at the second time point meet the secondary preset condition relationship; if so, proceed to step S4; if not, repeat steps S1 to S2;

[0072] S4: disconnecting the charging and discharging circuits of all the cells in the battery pack, spraying fire-fighting agents to the battery pack through a fire-fighting pipe, and releasing inert gas into the interior of the container until the oxygen concentration inside the container is lower than a preset concentration.

[0073] In the present invention, the first moment is associated with the second moment, and the second moment is the next moment of the first moment; the first time point is associated with the second time point, and the second time point is the next moment of the first time point; however, the first time point is not the next moment of the second moment, and the second moment and the first time point are not associated with each other. In simple terms: the first moment and the second moment are not a moment in steps S1 to S4, and the first time point and the second time point are not a moment in step S0.

[0074] In detail, the above-mentioned one-time preset condition relationship includes satisfying the following conditions at the same time:

[0075]

[0076] Among them, t b3 is the first time point, P b3 is the gas pressure inside the battery pack at the first time point, X b3 is the combustible gas concentration inside the battery pack at the first time point, t b4 is the second time point, P b4 is the gas pressure inside the battery pack at the second time point, X b4 is the combustible gas concentration inside the battery pack at the second time point, VP34 VX is the preset pressure change rate. 34 To preset the rate of change of the combustible gas concentration;

[0077] The secondary preset condition relationship includes satisfying at least one of the following conditions:

[0078] P b4 ≥P c

[0079] X b4 ≥X c

[0080] Among them, P c is the preset maximum air pressure, X c It is the preset maximum combustible gas concentration.

[0081] When the pressure change rate and the combustible gas concentration change rate of the battery pack exceed the preset pressure change rate and the preset pressure change rate respectively, it can be judged that the battery pack may have thermal runaway. However, in order to prevent misjudgment and affect the reliability of the energy storage box using the fire control method, when only the primary preset condition relationship is met and the secondary preset condition relationship is not met, the secondary fire strategy is not executed, but steps S1 to S2 are repeated until the battery pack state parameters at the first time point and the battery pack state parameters at the second time point simultaneously meet the primary preset condition relationship and the secondary preset condition relationship, and then the secondary fire strategy is executed.

[0082] In detail, in this embodiment, the secondary fire fighting strategy includes: (1) disconnecting the charging and discharging circuits of all cells in the battery pack; (2) injecting inert gas into the interior of the container through an inerting device to reduce the oxygen content in the container and reduce the possibility of fire in the container; preferably, the pressure relief port of the container is provided with a fan and an oxygen concentration detection device, the fan can accelerate the discharge of air from the interior of the container, the oxygen concentration detection device can detect the oxygen concentration of the air inside the container, and the oxygen concentration detection device can stop injecting inert gas into the container when it detects that the oxygen concentration is lower than a preset concentration, and the preset concentration can be set to 4%; (3) the fire fighting pipe sprays the fire fighting agent into the battery pack through the connection port of the battery pack to avoid fire inside the battery pack.

[0083] Preferably, in the present embodiment, the fire-fighting pipe 9 is provided with a pipe valve 22 corresponding to each battery cluster 21. When a battery pack 7 thermally runs away, the pipe valve 22 corresponding to the battery cluster 21 to which the battery pack 7 belongs is opened to spray fire-fighting agents on the battery packs 7 of the battery cluster 21, thereby improving the reliability of the secondary fire-fighting strategy and reducing the probability that thermal runaway of a battery pack 7 will cause thermal runaway of other battery packs 7 in the battery cluster 21 to which the battery pack 7 belongs, and cause heat spread to the battery cluster 21.

[0084] like Figure 5 As shown, the battery pack is provided with cells 1-1, 1-2, 1-3, 1-4, and 1-5 arranged in a matrix. For example, when cell 1-3 experiences thermal runaway, any cell adjacent to cell 1-3 also experiences thermal runaway, and it can be determined that the battery pack to which cell 1-3 belongs enters the thermal spread stage. Therefore, in this embodiment, the thermal spread condition includes that the cell state parameters of two adjacent cells satisfy the cell thermal runaway condition.

[0085] In order to prevent the heat of the battery cluster to which the battery in the heat spread stage belongs from spreading to the surrounding battery clusters, in this embodiment, the battery cluster fire protection module for performing fire protection control on the battery cluster includes a liquid cooling pipeline, which is respectively connected to each of the battery clusters and has a plurality of liquid cooling valves arranged on the liquid cooling pipeline.

[0086] The third-level fire protection strategy includes opening only the liquid cooling valves that flow to the battery cluster to which the battery pack experiencing heat spread belongs.

[0087] For ease of understanding, as an example, Figure 7 The container shown includes battery clusters 21-1 to 21-5 arranged in sequence along the liquid cooling pipe near its water inlet, and liquid cooling valves 17-1 to 17-4 are arranged in sequence on the liquid cooling pipe in the direction close to its water inlet. The liquid cooling valve is arranged between two adjacent battery clusters. When the fire control system implements the fourth-level fire strategy, there are the following liquid cooling working conditions:

[0088] (1) When heat spread occurs in a battery pack in the battery cluster 21-1, the liquid cooling valves 17-1 to 17-4 are opened, and the other liquid cooling valves are closed to cool the battery cluster 21-1 with the maximum liquid cooling power;

[0089] (2) When heat spread occurs in a battery pack in the battery cluster 21-2, the liquid cooling valves 17-2 to 17-4 are opened, and the other liquid cooling valves are closed to cool the battery cluster 21-2 with the maximum liquid cooling power;

[0090] (3) When heat spread occurs in a battery pack in the battery cluster 21-3, the liquid cooling valves 17-3 to 17-4 are opened, and other liquid cooling valves are closed to cool the battery cluster 21-3 with the maximum liquid cooling power;

[0091] (4) When heat spread occurs in a battery pack in the battery cluster 21-4, the liquid cooling valve 17-4 is opened, and other liquid cooling valves are closed to cool the battery cluster 21-4 with the maximum liquid cooling power;

[0092] (5) When heat spread occurs in a battery pack in the battery cluster 21 - 5 , all liquid cooling valves are closed and the battery cluster 21 - 5 is cooled with maximum liquid cooling power.

[0093] The three-level fire fighting strategy of this embodiment takes cooling the battery cluster to which the heat-spreading battery pack belongs as the first priority. Controlling the liquid cooling valve by the above method can improve the cooling efficiency of the battery cluster to which the heat-spreading battery pack belongs.

[0094] During the execution of the above three-level fire protection strategy, the temperature of the battery cluster may be monitored to ensure the reliability of the three-level fire protection strategy.

[0095] In this embodiment, when the heat spread cannot be effectively controlled, the battery pack 7 may catch fire and the flames may extend to the inside of the container, causing a fire. At this time, the energy storage box will enter the heat diffusion stage. In this embodiment, for the characteristics of the above heat diffusion stage and the fire extinguishing requirements, please refer to Figure 7 The fourth-level fire control module includes: a water filling mechanism and a camera 18 and a nozzle 19 arranged in the container 12 , and the water filling mechanism is connected to the water filling inlet 15 in the container 12 .

[0096] In step S6 of the fire control method provided in this embodiment, the second operating state of the container to which the battery pack belongs is obtained. When the second operating state meets the heat diffusion condition, the four-level fire protection strategy is executed, which specifically includes:

[0097] The fire information inside the container is obtained. When a flame appears in the container, the second operating state satisfies the heat diffusion condition. The nozzle sprays the fire extinguishing agent to the battery cluster to extinguish the flame. When the nozzle finishes spraying the fire extinguishing agent and the flame is not extinguished, the water filling mechanism fills water into the box body of the energy storage box.

[0098] Specifically, in this embodiment, the image information of the interior of the container is collected by a camera, and whether a flame is present in the container is determined based on the image information. That is, in this embodiment, the heat diffusion condition is that a flame exists in the container.

[0099] In this embodiment, when it is determined that a flame occurs in the container 12, a fire extinguishing agent is sprayed inside the container 12 through the nozzle 19; specifically, the fire extinguishing agent may be a gas fire extinguishing agent such as perfluorohexanone, heptafluoropropane, or a water-based fire extinguishing agent such as fine water mist. After the nozzle 19 has finished spraying the fire extinguishing agent, when it is determined that a flame occurs in the container 12 based on the image information collected by the camera 18, water is poured into the box body of the energy storage box through the water filling mechanism until the water level in the container 12 reaches the position of the water immersion sensor 20 provided on the bracket of the battery cluster 21.

[0100] In summary, the fire control method provided by the present invention establishes level one to level four fire control architectures corresponding to the battery cells, battery packs, battery clusters and containers of the energy storage box, and the fire control method sets fire judgment conditions and fire strategies corresponding to each level to ensure that the energy storage box can start fire control from the occurrence of thermal runaway of low-level energy storage elements, which is beneficial to transient fire judgment and processing, ensures that the execution of the fire strategy is synchronized with the thermal runaway state and fire state of the energy storage elements of the energy storage box, and reduces the damage to the energy storage elements during the execution of the fire control method, so as to avoid damage to the energy storage box and inconvenience in use due to the fire control method being triggered by mistake.

[0101] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A fire control method, characterized in that: The following steps are involved: S1: respectively obtaining a battery pack state parameter of a battery pack at a first time point and a battery pack state parameter of the battery pack at a second time point, wherein the first time point is a moment after the second time point; wherein the battery pack state parameter includes an air pressure inside the battery pack and a combustible gas concentration inside the battery pack; S2: Determine whether the battery pack state parameter of the battery pack at the first time point and the battery pack state parameter of the battery pack at the second time point satisfy a preset condition relationship; if so, proceed to step S3; if not, repeat steps S1 to S2; S3: Determine whether the battery pack state parameter of the battery pack at the first time point and the battery pack state parameter of the battery pack at the second time point meet the secondary preset condition relationship; if so, proceed to step S4; if not, repeat steps S1 to S2; S4: disconnecting the charge and discharge circuits of all cells in the battery pack; The primary preset condition relationship includes simultaneously satisfying the following conditions: Among them, t b3 is the first time point, P b3 is the gas pressure inside the battery pack at the first time point, X b3 is the combustible gas concentration inside the battery pack at the first time point, t b4 is the second time point, P b4 is the gas pressure inside the battery pack at the second time point, X b4 is the combustible gas concentration inside the battery pack at the second time point, VP 34 VX is the preset pressure change rate. 34 To preset the rate of change of the combustible gas concentration; The secondary preset condition relationship includes satisfying at least one of the following conditions: P b4 ≥P c X b4 ≥X c Among them, P c is the preset maximum air pressure, X c It is the preset maximum combustible gas concentration.

2. The fire control method according to claim 1, characterized in that: In step S4, the following steps are also included: a fire-fighting pipeline sprays a fire-fighting agent toward the battery pack.

3. The fire control method according to claim 1, characterized in that: In step S4, the method further includes releasing inert gas inside the container.

4. The fire control method according to claim 3, characterized in that: In step S4, the following step is also included: when the oxygen concentration inside the container is lower than a preset concentration, the injection of inert gas into the container is stopped.

5. The fire control method according to claim 1, characterized in that: After step S4, step S5 is also included: respectively obtaining the cell state parameters of all the cells in the battery pack; when the cell state parameters of two adjacent cells both meet the cell thermal runaway conditions, the first operating state meets the heat spread conditions, and the liquid cooling mechanism cools the battery cluster to which the battery pack belongs.

6. The fire control method according to claim 5, characterized in that: After step S5, step S6 is also included: obtaining fire information inside the container, when a flame appears in the container, the second operating state satisfies the heat diffusion condition; the nozzle sprays the fire extinguishing agent to the battery cluster to extinguish the flame; when the nozzle sprays the fire extinguishing agent and the flame is not extinguished, the water filling mechanism fills water into the box body of the energy storage box.

7. A fire control system, wherein the fire energy storage system comprises an energy storage box, the energy storage box comprises a container and a plurality of battery clusters arranged in the container, the battery cluster comprises a plurality of battery packs, the battery pack comprises a plurality of battery cells, the fire control system is used to execute the fire control method according to any one of claims 1 to 6, characterized in that: A battery pack fire protection module is included for performing fire protection control on the battery pack.

8. The fire control system according to claim 7, characterized in that: The battery pack fire protection module includes an air pressure sensor, a combustible gas sensor, a fire protection pipe, an inert gas injection pipe and an oxygen concentration detection device. The air pressure sensor and the combustible gas sensor are both arranged in the battery pack. The container is provided with a pressure relief port. The oxygen concentration detection device is arranged in the pressure relief port. The fire protection pipe is arranged in the container. The battery pack is provided with a connecting port, and the fire protection pipe is connected to the connecting port.

9. The fire control system according to claim 7, characterized in that: It also includes a battery cell fire protection module for performing fire protection control on the battery cell, and the battery cell fire protection module includes a deformation detector, a temperature detector and a voltage detector. The deformation detector is arranged on the explosion-proof valve of the battery cell, and the temperature detector and the voltage detector are respectively arranged on two electrode columns of the battery cell.

10. The fire control system according to claim 7, characterized in that: It also includes a container fire fighting module for controlling fire fighting of the container, and the container fire fighting module includes a water filling mechanism, a camera and a sprinkler, wherein the camera and the sprinkler are both arranged in the container, and the water filling mechanism is connected to a water filling inlet in the container.

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