Thermal runaway control method, control module, computer readable medium and battery pack

Abstract

The present invention discloses a control method for thermal runaway, which relates to the technical field of immersed battery packs, and is used for a control module of a battery pack. The control method comprises the following steps: obtaining the temperature of the battery; when the temperature of the battery is greater than a preset first temperature threshold A, obtaining at least one operating parameter of the battery; when at least one operating parameter is not within a set safety range, controlling an execution unit corresponding to the operating parameter that exceeds the set safety range to execute corresponding control measures. The present invention helps to avoid the occurrence of battery pack fire accidents or mitigate their impact.

Description

Technical Field

[0001] The present invention relates to the technical field of immersed battery packs, and in particular to a thermal runaway control method, a control module, a computer-readable medium and a battery pack. Background Art

[0002] Electrochemical energy storage systems have the advantages of high energy density, fast response speed, and easy grid connection. Electrochemical energy storage is mainly based on batteries, which have great advantages in energy storage density, efficiency, and charge and discharge rate. It has the characteristics of both safety and economy, and has developed rapidly. Electrochemical energy storage mainly includes lithium-ion batteries, lead-acid batteries, flow batteries, sodium-based batteries and other types.

[0003] Lithium-ion batteries are widely used in energy storage power stations. Currently, the boiling point of organic solvents in lithium-ion battery electrolytes is relatively low. When the battery is overheated, overcharged, or over-discharged, it may cause fire or even explosion, which not only endangers personal and property safety, but also has a certain negative impact on the development of the energy storage industry. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art to a certain extent. To this end, the present invention provides a thermal runaway control method, a control module, a computer readable medium and a battery pack.

[0005] In order to achieve the above object, a first aspect of the present invention provides a thermal runaway control method for a control module of a battery pack; the control method comprises the following steps:

[0006] obtaining a temperature of the battery;

[0007] When the temperature of the battery is greater than a preset first temperature threshold A, obtaining at least one operating parameter of the battery;

[0008] When at least one of the operating parameters is not within the set safety range, the execution unit corresponding to the operating parameter exceeding the set safety range is controlled to execute corresponding control measures.

[0009] Optionally, in the step of obtaining at least one operating parameter of the battery, an electrical parameter of the battery is obtained, the electrical parameter including at least one of temperature, heating rate, voltage and voltage drop rate;

[0010] When at least one of the operating parameters is not within the set safety range, controlling the execution unit corresponding to the operating parameter exceeding the set safety range to execute corresponding control measures includes:

[0011] When the temperature of the battery is greater than a preset second temperature threshold A and less than a preset third temperature threshold B, controlling the cooling unit to cool at a preset first power, and the second temperature threshold B is greater than the first temperature threshold A;

[0012] When the temperature of the battery is greater than a third temperature threshold B and less than a preset fourth temperature threshold C, the cooling unit is controlled to cool at a preset second power, and the battery is controlled not to be charged or discharged; the fourth temperature threshold C is greater than the second temperature threshold B, and the first power cooling is less than the second power;

[0013] When the temperature rise rate is greater than a preset temperature rise rate threshold, controlling the cooling unit to cool at a preset first power, and controlling the battery not to be charged or discharged;

[0014] When the voltage is less than a preset voltage threshold, controlling the cooling unit to cool at a preset first power, and controlling the battery not to be charged or discharged;

[0015] When the pressure drop rate is greater than a preset pressure drop rate, the cooling unit is controlled to cool at a preset first power, and the battery is controlled not to be charged or discharged.

[0016] Optionally, in the step of obtaining at least one operating parameter of the battery, chemical parameters of the coolant in the battery pack are obtained, the chemical parameters including at least one of water content and pH;

[0017] When at least one of the operating parameters is not within the set safety range, controlling the execution unit corresponding to the operating parameter exceeding the set safety range to execute corresponding control measures includes:

[0018] When the water content is greater than a preset water content threshold, controlling the cooling unit to input cooling liquid into the battery pack at a preset time interval;

[0019] When the pH value exceeds a preset pH value range, the cooling unit is controlled to input cooling liquid into the battery pack at preset time intervals.

[0020] Optionally, the step of controlling the cooling unit to input coolant into the battery pack at preset time intervals further includes controlling the cooling unit to input coolant into the battery pack in a preset amount each time.

[0021] Optionally, in the step of obtaining at least one operating parameter of the battery, a gas parameter in the battery pack is obtained, the gas parameter including at least one of gas pressure and carbon monoxide concentration;

[0022] When at least one of the operating parameters is not within the set safety range, controlling the execution unit corresponding to the operating parameter exceeding the set safety range to execute corresponding control measures includes:

[0023] When the air pressure is greater than a preset first air pressure threshold, the safety valve is controlled to open; when the air pressure is greater than a preset second air pressure threshold, the explosion-proof valve is controlled to open, and the second air pressure threshold is greater than the first air pressure threshold;

[0024] When the carbon monoxide concentration is greater than a preset carbon monoxide concentration threshold, the cooling unit is controlled to cool at a preset second power, and the battery is controlled not to be charged or discharged.

[0025] Optionally, when the air pressure is greater than a preset first air pressure threshold, after the safety valve is controlled to open, the method further includes:

[0026] The cooling unit is controlled to input cooling liquid into the battery pack at preset time intervals.

[0027] Optionally, in the step of obtaining at least one operating parameter of the battery, a temperature parameter of the coolant in the battery pack is obtained, the temperature parameter being the highest temperature of the coolant temperatures corresponding to multiple measuring points in the battery pack; when the highest temperature is greater than a preset second temperature threshold A and less than a preset third temperature threshold B, the cooling unit is controlled to cool at a preset first power, and the second temperature threshold B is greater than the first temperature threshold A;

[0028] When the maximum temperature is greater than the third temperature threshold B and less than the preset fourth temperature threshold C, the cooling unit is controlled to cool at a preset second power, and the battery is controlled not to charge or discharge; the fourth temperature threshold C is greater than the second temperature threshold B, and the first power cooling is less than the second power.

[0029] The second aspect of the present invention provides a control module, comprising: one or more processors; a memory on which one or more computer programs are stored, and when the one or more computer programs are executed by the one or more processors, the one or more processors implement the control method provided by the first aspect of the present invention.

[0030] The third aspect of the present invention provides a computer-readable medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the control method provided by the first aspect of the present invention.

[0031] A fourth aspect of the present invention provides a battery pack, comprising a box body, and a battery, a coolant and an inert gas arranged in the box body, wherein the battery is immersed in the coolant, and the gap between the liquid surface of the coolant and the top of the box body is filled with the inert gas. It is characterized in that the battery pack also includes the control module provided in the first aspect of the present invention.

[0032] These features and advantages of the present invention will be disclosed in detail in the following specific embodiments and drawings. The best embodiments or means of the present invention will be described in detail in conjunction with the drawings, but they are not intended to limit the technical solutions of the present invention. In addition, there are multiple features, elements, and components that appear in each of the following texts and drawings, and different symbols or numbers are marked for convenience, but they all represent components with the same or similar structures or functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be further described below in conjunction with the accompanying drawings:

[0034] Figure 1 It is a flow chart of the present invention.

[0035] Figure 2 It is a structural schematic diagram of the battery pack of the present invention at one angle.

[0036] Figure 3 It is a schematic structural diagram of the battery pack of the present invention from another angle.

[0037] Figure 4 Schematic diagram of the control module of the present invention.

[0038] Figure 5 A schematic diagram of a computer readable medium according to the present invention.

[0039] Among them, 1. box; 2. battery; 3. coolant; 4. inert gas; 5. safety exhaust valve; 6. detection probe; 7. coolant inlet; 101. processor; 102. memory; 103. I / O interface; 104. bus. DETAILED DESCRIPTION

[0040] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments in the implementation manner are intended to be used to explain the present invention and should not be construed as limiting the present invention.

[0041] References in this specification to "one embodiment" or "an example" or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment itself may be included in at least one embodiment of the present patent disclosure. The appearance of the phrase "in one embodiment" in various places in the specification does not necessarily refer to the same embodiment.

[0042] In related technologies, batteries are the core part of energy storage power stations. If the battery temperature is too high, the overall performance of the battery will decline, and there is a risk of thermal runaway, which may lead to safety accidents. The operating temperature range of lithium batteries is 20℃~50℃. Under normal working conditions, the current, voltage and internal resistance of the battery are in a relatively stable range. However, when the battery is short-circuited, overcharged, etc., these parameters will become abnormal, thus triggering an alarm.

[0043] The battery thermal management technology currently used in energy storage power stations is mainly active air cooling to reduce battery temperature. The immersed battery pack is an efficient battery cooling technology that has both cooling and temperature equalization effects, but the existing thermal runaway management technology of immersed battery packs still needs further improvement and optimization.

[0044] In view of this, refer to Figure 1 A first aspect of the present invention provides a method for controlling thermal runaway of a battery pack, which is used in a control module of an immersed battery pack; the control method comprises the following steps:

[0045] A first aspect of the present invention provides a thermal runaway control method for a control module of a battery pack; the control method comprises the following steps:

[0046] S110, obtaining the temperature of the battery;

[0047] S120, when the temperature of the battery is greater than a preset first temperature threshold A, obtaining at least one operating parameter of the battery; the first temperature threshold A is 45° C. to 50° C.;

[0048] S130. When at least one of the operating parameters is not within the set safety range, control the execution unit corresponding to the operating parameter that exceeds the set safety range to execute corresponding control measures.

[0049] Optionally, in the step of obtaining at least one operating parameter of the battery, an electrical parameter of the battery is obtained, the electrical parameter including at least one of temperature, heating rate, voltage and voltage drop rate;

[0050] When at least one of the operating parameters is not within the set safety range, controlling the execution unit corresponding to the operating parameter exceeding the set safety range to execute corresponding control measures includes:

[0051] When the temperature of the battery is greater than a preset second temperature threshold A and less than a preset third temperature threshold B, the cooling unit is controlled to cool at a preset first power, and the second temperature threshold B is greater than the first temperature threshold A; 45°C to 50°C, and the second temperature threshold B is 55°C to 65°C;

[0052] When the temperature of the battery is greater than the third temperature threshold B and less than the preset fourth temperature threshold C, the cooling unit is controlled to cool at the preset second power, and the battery is controlled not to charge or discharge; the fourth temperature threshold C is greater than the second temperature threshold B, and the first power cooling is less than the second power; the third temperature threshold C is 85°C to 90°C; in other embodiments, the first power can be equal to the second power, both are full power, and provide maximum cooling capacity.

[0053] When the heating rate is greater than the preset heating rate threshold, the cooling unit is controlled to cool at the preset first power, and the battery is controlled not to charge or discharge; the heating rate threshold is 8℃ / min~12℃ / min; the potential thermal runaway risk is discovered earlier, and timely measures are taken to intervene. For example, in actual applications, a certain energy storage system successfully started the cooling unit before the battery pack temperature rose to a dangerous value by real-time monitoring of the battery pack temperature and heating rate, and cut off the electrical connection with the outside world, avoiding a possible fire accident.

[0054] When the voltage is less than a preset voltage threshold, controlling the cooling unit to cool at a preset first power, and controlling the battery not to be charged or discharged;

[0055] When the pressure drop rate is greater than a preset pressure drop rate, the cooling unit is controlled to cool at a preset first power, and the battery is controlled not to be charged or discharged.

[0056] Optionally, in the step of obtaining at least one operating parameter of the battery, chemical parameters of the coolant in the battery pack are obtained, the chemical parameters including at least one of water content and pH;

[0057] When at least one of the operating parameters is not within the set safety range, controlling the execution unit corresponding to the operating parameter exceeding the set safety range to execute corresponding control measures includes:

[0058] When the water content is greater than a preset water content threshold, controlling the cooling unit to input cooling liquid into the battery pack at a preset time interval;

[0059] When the pH value exceeds a preset pH value range, the cooling unit is controlled to input cooling liquid into the battery pack at preset time intervals.

[0060] In other embodiments, when the temperature of the battery reaches a third temperature threshold C, the water content is greater than a preset water content threshold, and the pH exceeds a preset pH range, the cooling unit is controlled to input coolant into the battery pack at preset time intervals.

[0061] Optionally, the step of controlling the cooling unit to input coolant into the battery pack at preset time intervals further includes controlling the cooling unit to input coolant into the battery pack in a preset amount each time.

[0062] Optionally, the control method according to claim 1 is characterized in that, in the step of obtaining at least one operating parameter of the battery, a gas parameter in the battery pack is obtained, and the gas parameter includes at least one of gas pressure and carbon monoxide concentration;

[0063] When at least one of the operating parameters is not within the set safety range, controlling the execution unit corresponding to the operating parameter exceeding the set safety range to execute corresponding control measures includes:

[0064] When the air pressure is greater than a preset first air pressure threshold, the safety valve is controlled to open; when the air pressure is greater than a preset second air pressure threshold, the explosion-proof valve is controlled to open, and the second air pressure threshold is greater than the first air pressure threshold;

[0065] When the carbon monoxide concentration is greater than a preset carbon monoxide concentration threshold, the cooling unit is controlled to cool at a preset second power, and the battery is controlled not to be charged or discharged.

[0066] Optionally, when the air pressure is greater than a preset first air pressure threshold, after the safety valve is controlled to open, the method further includes:

[0067] The cooling unit is controlled to input cooling liquid into the battery pack at preset time intervals.

[0068] Optionally, in the step of obtaining at least one operating parameter of the battery, a temperature parameter of the coolant in the battery pack is obtained, the temperature parameter being the highest temperature of the coolant temperatures corresponding to multiple measuring points in the battery pack; when the highest temperature is greater than a preset second temperature threshold A and less than a preset third temperature threshold B, the cooling unit is controlled to cool at a preset first power, and the second temperature threshold B is greater than the first temperature threshold A;

[0069] When the maximum temperature is greater than the third temperature threshold B and less than the preset fourth temperature threshold C, the cooling unit is controlled to cool at a preset second power, and the battery is controlled not to charge or discharge; the fourth temperature threshold C is greater than the second temperature threshold B, and the first power cooling is less than the second power.

[0070] A second aspect of the present invention provides a control module, wherein: Figure 4 As shown, the control module includes: one or more processors 101; a memory 102, on which one or more computer programs are stored. When the one or more computer programs are executed by the one or more processors 101, the one or more processors 101 implement the control method provided by the first aspect of the present invention.

[0071] The control module may further include one or more I / O interfaces 103 connected between the processor 101 and the memory 102 and configured to implement information interaction between the processor 101 and the memory 102 .

[0072] Among them, the processor 101 is a device with data processing capabilities, including but not limited to the central processing unit 101 (CPU), etc.; the memory 102 is a device with data storage capabilities, including but not limited to random access memory 102 (RAM, more specifically such as SDRAM, DDR, etc.), read-only memory 102 (ROM), electrically erasable programmable read-only memory 102 (EEPROM), flash memory (FLASH); the I / O interface 103 (read-write interface) is connected between the processor 101 and the memory 102, and can realize information interaction between the processor 101 and the memory 102, including but not limited to the data bus 104 (Bus), etc.

[0073] In some embodiments, the processor 101, the memory 102, and the I / O interface 103 are connected to each other via a bus 104, and further connected to other components of the control module.

[0074] A third aspect of the present invention is as follows Figure 5 As shown, a computer-readable medium is provided, on which a computer program is stored, characterized in that when the computer program is executed by a processor, the control method provided by the first aspect of the present invention is implemented.

[0075] like Figure 2 and Figure 3 As shown, the fourth aspect of the present invention provides a battery pack, including a box body 1, and a battery 2, a coolant 3 and an inert gas 4 arranged in the box body, the battery 1 is immersed in the coolant 3, and the gap between the liquid surface of the coolant 3 and the top of the box body 1 is filled with the inert gas 4. The battery pack also includes the control module provided by the first aspect of the present invention.

[0076] The top of the box 1 is also provided with a safety exhaust valve 5 and an explosion-proof valve (not shown in the figure). When the gas pressure in the box reaches a certain level, that is, reaches the first threshold, the safety exhaust valve 5 automatically opens to discharge the gas to prevent potential dangers. To protect the safety of users and equipment, the battery is usually provided with a safety valve. When the internal pressure of the battery is too high, the safety valve will automatically release the pressure to prevent the battery from exploding or leaking. The pressure inside the battery usually comes from the gas released by the chemical reaction. After the safety valve is opened, smoke is generated and a sound of leakage is emitted. When the gas pressure in the box 1 reaches a certain level, that is, the second threshold, the explosion-proof valve will passively open to further ensure the safety of the device.

[0077] A temperature sensor (not shown in the figure) is provided at each of the four corners of the box 1. The four temperature sensors can detect the temperature of the battery pack in real time to define whether thermal runaway occurs and the thermal runaway stage of the battery pack;

[0078] A plurality of detection probes 6 are also arranged in the box 1, and the detection probes are used to detect the water content, pH value, gas pressure, carbon monoxide concentration, etc. of the coolant. When the lithium-ion battery is in abnormal conditions such as overheating or overcharging, its internal temperature will rise, causing chemical reactions such as electrolyte decomposition and SEI film decomposition, thereby generating gases such as oxygen, hydrogen, and ethylene. The gases generated by the lithium-ion battery when it fails and the proportion they occupy are generally higher in carbon dioxide, followed by carbon monoxide. This embodiment uses carbon monoxide concentration as the basis for detection.

[0079] The side wall of the box body 1 is provided with a coolant inlet 7 and a coolant outlet for communicating with an external cooling unit, and the external cooling unit provides coolant to the box body 1 .

[0080] The present invention can detect battery fire risks in advance, and by collecting, detecting and analyzing parameters such as battery voltage, temperature, gas pressure inside the battery pack, pH value and water content changes of the immersion liquid, it can identify abnormal situations and make corresponding interventions, which helps to avoid the occurrence of fire accidents or reduce their impact. The present invention is used to suppress the occurrence of immersed battery pack fires and prevent the spread of fires.

[0081] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that the present invention includes but is not limited to the contents described in the drawings and the above specific embodiments. Any modification that does not deviate from the functional and structural principles of the present invention will be included in the scope of the claims.

Claims

1. A thermal runaway control method for a control module of a battery pack; characterized in that: The control method comprises the following steps: obtaining a temperature of the battery; When the temperature of the battery is greater than a preset first temperature threshold A, obtaining at least one operating parameter of the battery; When at least one of the operating parameters is not within the set safety range, the execution unit corresponding to the operating parameter exceeding the set safety range is controlled to execute corresponding control measures.

2. The control method according to claim 1, characterized in that: In the step of obtaining at least one operating parameter of the battery, an electrical parameter of the battery is obtained, wherein the electrical parameter includes at least one of temperature, heating rate, voltage and voltage drop rate; When at least one of the operating parameters is not within the set safety range, controlling the execution unit corresponding to the operating parameter exceeding the set safety range to execute corresponding control measures includes: When the temperature of the battery is greater than a preset second temperature threshold A and less than a preset third temperature threshold B, controlling the cooling unit to cool at a preset first power, and the second temperature threshold B is greater than the first temperature threshold A; When the temperature of the battery is greater than a third temperature threshold B and less than a preset fourth temperature threshold C, the cooling unit is controlled to cool at a preset second power, and the battery is controlled not to be charged or discharged; the fourth temperature threshold C is greater than the second temperature threshold B, and the first power cooling is less than the second power; When the temperature rise rate is greater than a preset temperature rise rate threshold, controlling the cooling unit to cool at a preset first power, and controlling the battery not to be charged or discharged; When the voltage is less than a preset voltage threshold, controlling the cooling unit to cool at a preset first power, and controlling the battery not to be charged or discharged; When the pressure drop rate is greater than a preset pressure drop rate, the cooling unit is controlled to cool at a preset first power, and the battery is controlled not to be charged or discharged.

3. The control method according to claim 1, characterized in that: In the step of obtaining at least one operating parameter of the battery, chemical parameters of the coolant in the battery pack are obtained, wherein the chemical parameters include at least one of water content and pH; When at least one of the operating parameters is not within the set safety range, controlling the execution unit corresponding to the operating parameter exceeding the set safety range to execute corresponding control measures includes: When the water content is greater than a preset water content threshold, controlling the cooling unit to input cooling liquid into the battery pack at a preset time interval; When the pH value exceeds a preset pH value range, the cooling unit is controlled to input cooling liquid into the battery pack at preset time intervals.

4. The control method according to claim 3, characterized in that: The step of controlling the cooling unit to input cooling liquid into the battery pack at preset time intervals further includes controlling the cooling unit to input cooling liquid into the battery pack in a preset amount each time.

5. The control method according to claim 1, characterized in that: The control method according to claim 1, characterized in that in the step of obtaining at least one operating parameter of the battery, a gas parameter in the battery pack is obtained, the gas parameter comprising at least one of gas pressure and carbon monoxide concentration; When at least one of the operating parameters is not within the set safety range, controlling the execution unit corresponding to the operating parameter exceeding the set safety range to execute corresponding control measures includes: When the air pressure is greater than a preset first air pressure threshold, the safety valve is controlled to open; when the air pressure is greater than a preset second air pressure threshold, the explosion-proof valve is controlled to open, and the second air pressure threshold is greater than the first air pressure threshold; When the carbon monoxide concentration is greater than a preset carbon monoxide concentration threshold, the cooling unit is controlled to cool at a preset second power, and the battery is controlled not to be charged or discharged.

6. The control method according to claim 5, characterized in that: When the air pressure is greater than a preset first air pressure threshold, after controlling the safety valve to open, the method further includes: controlling the cooling unit to input cooling liquid into the battery pack at preset time intervals.

7. The control method according to claim 1, characterized in that: In the step of obtaining at least one operating parameter of the battery, a temperature parameter of a coolant in the battery pack is obtained, wherein the temperature parameter is the highest temperature of the coolant temperatures corresponding to a plurality of measuring points in the battery pack; When the maximum temperature is greater than a preset second temperature threshold A and less than a preset third temperature threshold B, the cooling unit is controlled to cool at a preset first power, and the second temperature threshold B is greater than the first temperature threshold A; When the maximum temperature is greater than the third temperature threshold B and less than the preset fourth temperature threshold C, the cooling unit is controlled to cool at a preset second power, and the battery is controlled not to charge or discharge; the fourth temperature threshold C is greater than the second temperature threshold B, and the first power cooling is less than the second power.

8. A control module, characterized in that: include: One or more processors (101); a memory (102) having one or more computer programs stored thereon, wherein when the one or more computer programs are executed by the one or more processors (101), the one or more processors (101) implement the control method according to any one of claims 1 to 7.

9. A computer readable medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor (101), the control method according to any one of claims 1 to 7 is implemented.

10. A battery pack, comprising a box, and a battery, a coolant and an inert gas arranged in the box, wherein the battery is immersed in the coolant, and the gap between the liquid surface of the coolant and the top of the box is filled with the inert gas, characterized in that: The battery pack further comprises a control module as claimed in any one of claims 1-7.

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