Battery protection method, battery protection system and battery pack
By simulated and detected the deformation displacement of the explosion-proof valve of a single battery, the safe displacement amount was determined, and a displacement sensor and protection device were set up in the battery pack, and the control was controlled by an industrial control machine, the problem of inaccurate detection of the pressure relief threshold of the explosion-proof valve was solved. Improves the safety of the battery pack.
Patent Information
- Application Number
- CN202411564130.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-04
- Publication Date
- 2025-02-18
AI Technical Summary
In the prior art, the detection of the pressure relief threshold of the explosion-proof valve is inaccurate, resulting in poor safety of the battery pack.
By simulating and detecting the deformation displacement of a single battery explosion-proof valve under thermal runaway situation, the safe displacement of the explosion-proof valve is determined, and a displacement sensor and protection device are installed at the battery explosion-proof valve position, the displacement change is detected by the industrial control machine, and the cutting is controlled. Battery pack power and isolate protection.
It improves the detection accuracy of explosion-proof valve burst timing, reduces the impact of thermal runaway in a single cell on other single cells, thereby improving the overall safety of the battery pack.
Smart Images
Figure CN119482807A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of power batteries, and in particular, to a battery protection method, a battery protection system and a battery pack. Background Art
[0002] As an important component of new energy batteries, explosion-proof valves can provide pressure relief protection when thermal runaway occurs inside the battery, preventing greater harm from explosions caused by excessive pressure and heat accumulation inside the battery. Therefore, the timing of pressure relief of explosion-proof valves is crucial to the safety of batteries.
[0003] In the prior art, the timing of pressure relief of the explosion-proof valve is usually determined by detecting the pressure threshold of the explosion-proof valve. However, due to the influence of factors such as processing errors that may exist during the production and processing of the explosion-proof valve, the pressure thresholds of the same batch of explosion-proof valves with the same structure may be different. Therefore, the above detection method has the problem of inaccurate detection, resulting in poor safety of the explosion-proof valve and the battery pack. Summary of the invention
[0004] The purpose of the present application is to provide a battery protection method, a battery protection system and a battery pack, which can solve the problem of poor safety caused by inaccurate detection of the pressure relief threshold of the explosion-proof valve in the prior art.
[0005] In order to achieve the above-mentioned purpose, according to the first aspect of the present application, an embodiment of the present application provides a battery protection method, which includes the following steps: first, simulate the deformation displacement of the explosion-proof valve of the single battery under thermal runaway conditions. Then, the safe displacement of the explosion-proof valve under thermal runaway conditions is determined based on the simulation test results. A displacement sensor is set at the position of the battery explosion-proof valve to detect the displacement change of the explosion-proof valve, and a protection device is set at the same time. The displacement change data detected by the displacement sensor is transmitted to the industrial computer. When the displacement change is greater than or equal to the safe displacement, the industrial computer controls to cut off the power supply of the battery pack, and at the same time, the industrial computer controls the protection device to perform isolation protection.
[0006] Based on the above-mentioned embodiments of the present application, firstly, the deformation displacement of the explosion-proof valve on the single battery under thermal runaway is simulated and detected to determine the safe displacement of the explosion-proof valve, that is, the limit displacement of the explosion-proof valve before the explosion occurs. Then, when the battery is grouped, a displacement sensor is set at the position of the battery explosion-proof valve, and a protection device is set at the same time. When the displacement sensor detects that the displacement of the explosion-proof valve exceeds the safe displacement, the explosion-proof valve is about to have thermal runaway. The displacement sensor transmits the detection data feedback to the industrial computer, and then the industrial computer controls the battery power supply to be cut off on the one hand, and on the other hand, the industrial computer controls the protection device to move to the explosion-proof valve position for protection to avoid the explosion of the explosion valve. The impact on other single batteries. When the battery is in thermal runaway, the internal pressure of the single battery increases and the temperature rises, which in turn pushes the explosion-proof valve to start displacement and eventually burst. Therefore, the explosion-proof valve must undergo a displacement process before bursting, and when the explosion-proof valve structure is constant, the displacement from the initial position of the explosion-proof valve to the time of bursting remains stable. Therefore, through the above-mentioned setting of the present application, compared with the method of detecting the pressure threshold of the explosion-proof valve in the prior art, the timing of the explosion of the explosion-proof valve is determined more accurately. At the same time, the setting of the protection device reduces the impact of thermal runaway of a single single cell on other single cells, thereby improving the safety of the battery.
[0007] In some embodiments, when simulating the deformation and displacement of the explosion-proof valve of a single battery, the simulation is performed by simultaneously inflating, pressurizing, and heating the battery housing.
[0008] Based on the above-mentioned embodiments of the present application, when a single cell battery experiences thermal runaway, a large amount of high-temperature gas will be rapidly generated inside the battery, causing the temperature inside the battery to rise and the pressure to increase. Therefore, by simultaneously inflating, pressurizing and heating the battery casing, the simulation of the state inside the battery during thermal runaway is made more accurate, thereby enhancing the accuracy of the simulation detection.
[0009] In some embodiments, when pressurizing the battery casing, the initial pressure in the battery casing is P, and as the pressurizing process proceeds, the pressure in the battery casing gradually increases, 0.1 MPa≤P≤0.8 MPa.
[0010] Based on the above-mentioned embodiments of the present application, when the single cell is in normal use, the battery is in a sealed state as a whole, and during the process of charging and discharging the battery, the water inside the battery and the gas generated by the decomposition of the organic solution will accumulate inside the battery, causing the pressure inside the battery to increase. Under normal circumstances, the pressure inside the battery will be higher than the external atmospheric pressure while being maintained within a normal range, and when the battery thermally runs away, the internal pressure of the battery will rapidly increase and exceed the normal pressure range. Therefore, by limiting the initial pressure in the battery casing during the simulation test, the test results are made more accurate. Subsequently, the pressure in the battery casing is gradually increased by continuously pressurizing until the explosion-proof valve bursts, thereby simulating the situation where the explosion-proof valve bursts when the battery thermally runs away.
[0011] In some embodiments, when heating is applied to the battery casing, the temperature inside the battery casing is T, and as the heating process proceeds, the temperature T inside the battery casing gradually increases, and T≥25°C.
[0012] Based on the above-mentioned embodiments of the present application, when the single cell is in normal use, the battery is in a sealed state as a whole and generates a certain amount of heat when the battery is in operation, so the temperature inside the battery is usually between 20°C and 35°C. By limiting the temperature inside the battery casing during the simulation test, that is, limiting the initial temperature inside the battery during the simulation test, the test result is made more accurate. Then, the battery casing is continuously heated until the explosion-proof valve bursts, thereby simulating the explosion of the explosion-proof valve in the case of thermal runaway of the battery.
[0013] In some embodiments, the protection device is spaced from the explosion-proof valve by a distance L, 4 mm ≤ L ≤ 6 mm.
[0014] Based on the above-mentioned embodiments of the present application, by limiting the spacing distance between the protection device and the explosion-proof valve, it is possible to ensure that the industrial computer timely controls the protection device to move to the position of the explosion-proof valve to isolate and protect it, thereby avoiding affecting the safety of other single cells.
[0015] In some embodiments, the industrial computer is pre-set with a safe displacement range of the explosion-proof valve. When the displacement of the explosion-proof valve detected by the displacement sensor is greater than the safe displacement, the industrial computer controls the protection device to isolate and protect the explosion-proof valve.
[0016] Based on the above-mentioned embodiments of the present application, by pre-setting the safe displacement range of the explosion-proof valve on the industrial computer, the industrial computer can quickly and accurately determine whether the displacement exceeds the safe displacement after receiving the detection data transmitted by the displacement sensor. The entire judgment and control process is integrated in the industrial computer to achieve fast and accurate control.
[0017] In some embodiments, the protection device is configured as a protection cover, and the protection cover can be disposed on the outer wall of the battery housing at the location where the explosion-proof valve is disposed.
[0018] Based on the above-mentioned embodiments of the present application, by setting the protection device as a protective cover, when the industrial computer determines through the detection data of the displacement sensor that the displacement of the explosion-proof valve exceeds the safe displacement, the industrial computer controls the protective cover to move to the position of the explosion-proof valve to cover it, and then when the explosion-proof valve bursts, the high-temperature flue gas ejected by the explosion is confined in the protective cover, thereby avoiding affecting other single cells and improving the overall safety of the battery.
[0019] According to the second aspect of the present application, a battery protection system is provided, which is applicable to the above-mentioned battery protection method, and the battery protection system includes a displacement sensor, a protection device and an industrial computer. The displacement sensor is arranged at the battery explosion-proof valve position to detect the displacement of the explosion-proof valve. The protection device is arranged on the side of the battery pack explosion-proof valve to perform isolation protection before the explosion of the explosion-proof valve. The industrial computer is electrically connected to the displacement sensor and the protection device respectively, and the displacement sensor detects data and transmits it to the industrial computer. The industrial computer can control the cutting off of the power supply of the battery pack. At the same time, the industrial computer can control the movement of the protection device to the explosion-proof valve position to isolate and protect it.
[0020] Based on the above embodiments of the present application, through the setting of the above battery protection system, the battery uses a displacement sensor to detect the time when the battery explosion-proof valve is about to burst when in use, and cuts off the battery power supply through the industrial computer control when the explosion is about to occur, so as to avoid damage to other components. At the same time, the industrial computer controls the protection device to isolate and protect the explosion-proof valve position to avoid affecting other single batteries.
[0021] In some embodiments, the industrial computer includes a control module and an action module. The displacement sensor is electrically connected to the control module. The control module can control the action module to drive the protection device to isolate and protect the explosion-proof valve.
[0022] Based on the above-mentioned embodiments of the present application, when the industrial computer is used, on the one hand, it needs to receive the detection data of the displacement sensor through the control module, and at the same time compare the safe displacement to determine whether the displacement of the explosion-proof valve exceeds the safe displacement. When it is detected that the displacement of the explosion-proof valve exceeds the safe displacement, it is also necessary to control the battery power supply to be cut off through the action module, and on the other hand, it is also necessary to control the protection device to isolate and protect the explosion-proof valve.
[0023] According to a third aspect of the present application, a battery pack is provided, the battery pack comprising a plurality of single cells and the above-mentioned battery protection system. An explosion-proof valve is provided on the single cell, a displacement sensor is connected to the explosion-proof valve, and a protection device is provided on the side of the explosion-proof valve.
[0024] Based on the above-mentioned embodiments of the present application, the battery pack provided in the present application includes the above-mentioned battery protection system, and therefore also has the above-mentioned beneficial effects. In order to avoid repetition, they will not be described here.
[0025] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The accompanying drawings are used to provide a further understanding of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present application but do not constitute a limitation to the present application. In the accompanying drawings:
[0027] Figure 1 It is a schematic diagram of the steps of the battery protection method provided in an embodiment of the present application. DETAILED DESCRIPTION
[0028] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.
[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.
[0030] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.
[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.
[0032] In the description of this application, it should be noted that, in the absence of any contrary explanation, the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.
[0033] In the description of this application, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0034] As an important component of new energy batteries, explosion-proof valves can provide pressure relief protection when thermal runaway occurs inside the battery. Therefore, the timing of pressure relief of explosion-proof valves is crucial to the safety of batteries.
[0035] In the prior art, the timing of pressure relief of explosion-proof valves is usually determined by detecting the pressure threshold of explosion-proof valves. However, due to the influence of factors such as processing errors that may exist during the production and processing of explosion-proof valves, there may be differences in the pressure thresholds of explosion-proof valves of the same batch with the same structure. The pressure threshold used in actual use of explosion-proof valves is obtained by simulating and testing some explosion-proof valves. Therefore, in actual use, the bursting threshold may be greater than or less than the pressure threshold, which in turn affects the safety of the explosion-proof valve.
[0036] At the same time, when the battery is in use, after the explosion-proof valve of a single battery bursts and releases pressure, high-temperature smoke will be discharged into the battery box. At this time, the overall pressure inside the battery box increases, which in turn causes the external pressure on other explosion-proof valves that have not burst and released pressure to increase, affecting the accuracy of pressure detection of other explosion-proof valves.
[0037] In summary, the above-mentioned settings in the prior art lead to inaccurate detection of the pressure relief threshold of the explosion-proof valve, which in turn leads to poor safety of the explosion-proof valve and the battery pack as a whole.
[0038] In order to solve the above problems in the prior art, according to the first aspect of the present application, reference is made to Figure 1 As shown in , an embodiment of the present application provides a battery protection method, which includes the following steps: first, simulate the deformation displacement of the explosion-proof valve of the single battery under thermal runaway conditions. Then, the safe displacement of the explosion-proof valve under thermal runaway conditions is determined based on the simulation test results. A displacement sensor is set at the position of the battery explosion-proof valve to detect the displacement change of the explosion-proof valve, and a protection device is set at the same time. The displacement change data detected by the displacement sensor is transmitted to an industrial computer. When the displacement change is equal to or greater than the safe displacement, the industrial computer controls to cut off the power supply of the battery pack, and at the same time, the explosion-proof valve position is protected by controlling the protection device through the industrial computer.
[0039] Based on the above-mentioned embodiments of the present application, firstly, the deformation displacement of the explosion-proof valve on the single battery in the case of thermal runaway is simulated and detected to determine the safe displacement of the explosion-proof valve, that is, the limit displacement of the explosion-proof valve before the explosion occurs. Then, when the batteries are arranged in groups, a displacement sensor is set at the position of the battery explosion-proof valve, and a protection device is also set. When the displacement sensor detects that the displacement of the explosion-proof valve reaches or exceeds the safe displacement, the explosion-proof valve is about to burst. The displacement sensor transmits the detection data feedback to the industrial computer. Then, the industrial computer controls the power supply of the battery pack to be cut off on the one hand, and controls the protection device to move to the position of the explosion-proof valve for protection on the other hand, so as to avoid the explosion of the explosion-proof valve affecting other single batteries.
[0040] When the battery experiences thermal runaway, the internal pressure of the single cell increases and the temperature rises, which in turn pushes the explosion-proof valve to start to move until it finally bursts. Therefore, the explosion-proof valve must undergo a displacement process before bursting, and when the explosion-proof valve structure is constant, the displacement from the initial position of the explosion-proof valve to the time of bursting remains stable. Therefore, through the above-mentioned setting of the present application, compared with the method of detecting the pressure threshold of the explosion-proof valve in the prior art, the determination of the timing of the explosion of the explosion-proof valve is more accurate. At the same time, the setting of the protection device reduces the impact of a single cell on other cells when thermal runaway occurs, thereby improving the safety of the battery.
[0041] Specifically, in the prior art, when detecting the pressure threshold of the explosion-proof valve by pressure detection, it is necessary to directly measure the pressure at the explosion-proof valve position. In a battery pack, when one of the single cells experiences thermal runaway and causes the explosion-proof valve to burst, high-temperature smoke is discharged into the battery pack, causing the overall pressure inside the battery pack to increase. At this time, the external pressure on the explosion-proof valves on other single cells increases, which in turn affects the accuracy of the pressure detection of the explosion-proof valves, affects the safety of other single cells, and reduces the overall safety of the battery pack.
[0042] With the above configuration of the present application, even if a single cell experiences thermal runaway and the explosion-proof valve bursts, causing the pressure in the battery pack to increase, this will not affect the displacement change of other single cells, and therefore will not affect the detection result of the displacement sensor. Therefore, it is still possible to maintain accurate detection of other single cells, ensuring the safety of the explosion-proof valves of other single cells when in use.
[0043] Furthermore, by setting up the protection device, the protection device separates and protects the explosion-proof valve position, so that the high-temperature flue gas can be limited to a limited range without affecting the explosion-proof valve burst pressure relief, avoiding affecting other single cells, thereby further improving the overall safety of the battery pack.
[0044] In the present application, the protection device can be set to any suitable structure. For example, in an exemplary embodiment provided in the present application, the protection device is set to a circular or rectangular protection cover, and when in use, the protection cover is buckled on the outside of the explosion-proof valve, and there is a certain space inside the protection device, so that the cover can be set outside the explosion-proof valve for isolation protection, and at the same time, when the explosion-proof valve bursts, space is reserved for the discharge of high-temperature smoke, and the high-temperature smoke is confined and isolated in the protection device.
[0045] Furthermore, in some other embodiments of the present application, the protection device can also be connected to structures such as the smoke exhaust channel of the battery pack. For example, when the protection device is set on a protective cover, the protective cover is directly connected to the smoke exhaust channel through a soft pipe. After the high-temperature flue gas is discharged into the protection device, it is directly transported to the smoke exhaust channel through the pipe, and then discharged from the smoke exhaust channel, thereby further reducing the impact on other single cells inside the battery pack when thermal runaway of some single cells occurs and the explosion-proof valve bursts.
[0046] In the present application, when simulating the detection of the deformation displacement of the explosion-proof valve of a single battery under thermal runaway conditions, any appropriate simulation detection method and equipment may be selected.
[0047] In some embodiments of the present application, when simulating the deformation and displacement of the explosion-proof valve of a single battery, the working state of the explosion-proof valve during thermal runaway of the battery can be simulated by simultaneously inflating, pressurizing and heating the battery housing.
[0048] Based on the above-mentioned embodiments of the present application, when a single cell battery experiences thermal runaway, a large amount of high-temperature gas will be rapidly generated inside the battery, causing the temperature inside the battery to rise and the pressure to increase. Therefore, by simultaneously inflating, pressurizing and heating the battery casing, the simulation of the state inside the battery during thermal runaway is made more accurate, thereby enhancing the accuracy of the simulation detection.
[0049] Specifically, in the prior art, thermal runaway of power batteries usually includes multiple processes. Taking lithium batteries as an example, the first is the reaction stage inside the battery, which is usually caused by factors such as a short circuit inside the battery or external heating. At this time, the temperature inside the battery will rise to about 90 degrees Celsius. At high temperatures, the solid electrolyte interface (SEI) film inside the lithium battery begins to decompose, and the lithium ions at the negative electrode of the battery begin to react with the electrolyte and the binder, causing the temperature inside the battery to further increase. At this time, the electrolyte begins to decompose, thereby releasing a large amount of heat.
[0050] Then comes the battery bulging stage, when the battery temperature rises further to over 200°C, the positive electrode material decomposes, releasing a large amount of heat and gas, and the temperature continues to rise. When the temperature reaches 250°C-350°C, the lithium-embedded negative electrode begins to react with the electrolyte.
[0051] Finally, the battery reaches the explosion failure stage. During the reaction, the charged positive electrode material begins to undergo a violent decomposition reaction, and the electrolyte undergoes a violent oxidation reaction, releasing a large amount of heat, generating high temperature and a large amount of gas, and the battery burns and explodes.
[0052] In this application, by pressurizing and heating the battery shell at the same time, the process of increasing the pressure inside the battery due to the gas generated inside the battery and increasing the temperature inside the battery due to the heat generated by the reaction inside the battery during the battery thermal runaway process is simulated. At the same time, in the specific simulation process, the inflation and heating rates can be adjusted according to the above-mentioned several processes of battery thermal runaway, so that the simulation process is closer to the real battery thermal runaway process, thereby making the deformation and displacement detection of the battery explosion-proof valve more accurate.
[0053] Furthermore, when the battery housing is pressurized, the initial pressure in the battery housing is P, and as the pressurization process proceeds, the pressure in the battery housing gradually increases until the explosion-proof valve bursts, wherein 0.1Mpa≤P≤0.8Mpa.
[0054] Based on the above-mentioned embodiments of the present application, when the single cell is in normal use, the battery is in a sealed state as a whole, and during the process of charging and discharging the battery, the water inside the battery and the gas generated by the decomposition of the organic solution will accumulate inside the battery, causing the pressure inside the battery to increase. Under normal circumstances, the pressure inside the battery will be higher than the external atmospheric pressure while being maintained within a normal range, and when the battery is in thermal runaway, the internal pressure of the battery will rapidly increase and exceed the normal pressure range. Therefore, by limiting the initial pressure in the battery casing during the simulation test, the initial pressure value during the simulation is closer to the internal pressure value of the battery during normal use, making the test result more accurate. Subsequently, the pressure in the battery casing is gradually increased by continuously pressurizing until the explosion-proof valve bursts, thereby simulating the specific process of the explosion-proof valve bursting during battery thermal runaway.
[0055] Specifically, according to the above-mentioned several processes of battery thermal runaway, it can be known that the gas release conditions in each stage of the battery thermal runaway process are different, so the rate of increase of the internal pressure of the battery is also different. Therefore, different pressurization rates can be set accordingly when pressurizing the battery casing.
[0056] Similarly, when the inside of the battery case is heated, the temperature inside the battery case is T. As the heating process proceeds, the temperature T inside the battery case gradually increases, wherein T≥25°C.
[0057] Based on the above-mentioned embodiments of the present application, when the single cell is in normal use, the battery is in a sealed state as a whole and generates a certain amount of heat when the battery is in operation, so the temperature inside the battery is usually between 20°C and 35°C. By limiting the temperature inside the battery casing during the simulation test, that is, limiting the initial temperature inside the battery during the simulation test, the test result is made more accurate. Then, by continuously heating the inside of the battery casing until the explosion-proof valve bursts, the specific process of the explosion-proof valve bursting in the case of thermal runaway of the battery is simulated.
[0058] According to the above-mentioned several processes of battery thermal runaway, the specific reactions in each stage of the battery thermal runaway process are different, so the heat released in each stage is also different. Therefore, different heating temperatures can be set accordingly when heating the inside of the battery casing.
[0059] In addition, it should be noted that when the deformation displacement of the explosion-proof valve of a single battery cell under thermal runaway is simulated in this application, the specific equipment used in the simulation test is not specifically limited. At the same time, in the actual simulation test process, in order to improve the accuracy of the test results, the accuracy of the test results can be improved by taking the average value through multiple simulation tests for the same explosion-proof valve.
[0060] In the present application, the spacing distance between the protection device and the explosion-proof valve is L, 4mm≤L≤6mm.
[0061] Based on the above-mentioned embodiments of the present application, by limiting the spacing between the protection device and the explosion-proof valve, it can be ensured that when the explosion-proof valve is about to burst, the industrial control computer can timely control the protection device to move to the explosion-proof valve position to isolate and protect it, thereby avoiding affecting the safety of other single cells. It can also avoid the protection device being too close to the explosion-proof valve to affect the normal opening of the explosion-proof valve.
[0062] Furthermore, the specific distance between the protection device and the explosion-proof valve can be set according to factors such as the specific structure of the protection device and the movement path of the protection device.
[0063] In the present application, the specific structure of the industrial computer can be set in any suitable manner.
[0064] In an exemplary embodiment provided in the present application, the industrial computer may include a control module and an action module, the displacement sensor is electrically connected to the control module, and the control module can control the action module to drive the protection device to isolate and protect the explosion-proof valve.
[0065] Based on the above-mentioned embodiments of the present application, when the industrial computer is used, on the one hand, it needs to receive the detection data of the displacement sensor through the control module, and at the same time compare the safe displacement to determine whether the displacement of the explosion-proof valve reaches the safe displacement. When it is detected that the displacement of the explosion-proof valve reaches or exceeds the safe displacement, it is also necessary to control the battery power supply to be cut off through the action module, and on the other hand, it is also necessary to control the protection device to isolate and protect the explosion-proof valve.
[0066] Specifically, the control module may include a storage module and a calculation module, etc., to receive the displacement data of the explosion-proof valve and process and compare the data. The specific configuration of the storage module and the calculation module may be any suitable configuration, and this application does not impose any specific restrictions on this.
[0067] The action module may include a power module and a transmission module. When it is detected that the displacement of the explosion-proof valve exceeds the safe displacement, the power module drives the transmission module to move the protection device to the explosion-proof valve position for separation protection. The power module may be configured as a motor and an electric cylinder, and the transmission module may be configured as a mechanical arm.
[0068] Furthermore, in some embodiments of the present application, the industrial computer may be pre-set with a safe displacement range of the explosion-proof valve. When the displacement of the explosion-proof valve detected by the displacement sensor is greater than the safe displacement, the industrial computer controls the protection device to isolate and protect the explosion-proof valve.
[0069] Based on the above-mentioned embodiments of the present application, by pre-setting the safe displacement range of the explosion-proof valve on the industrial computer, the industrial computer can quickly and accurately determine whether the displacement of the explosion-proof valve exceeds the safe displacement after receiving the detection data transmitted by the displacement sensor. The entire judgment and control process is integrated in the industrial computer to achieve fast and accurate control.
[0070] Specifically, in the present application, the specific process of cutting off the battery power by the industrial computer control can be selected in any appropriate manner. For example, a circuit breaker structure is connected to the connection line, or a trip structure is connected to the connection line, so that the battery power can be disconnected and cut off by the industrial computer control circuit.
[0071] In addition, it should be noted that the above-mentioned cutting off of battery power through industrial computer control in the present application can be cutting off the circuit connection between the entire battery pack and other electrical equipment, or it can be cutting off the circuit connection between a single cell or a single battery module and other parts. The specific selection can be based on the specific structure and setting method of the battery pack, etc., and the present application does not impose specific restrictions on this.
[0072] Furthermore, the specific structure of the explosion-proof valve is not limited in the present application. In the prior art, explosion-proof valves generally include piston-type explosion-proof valves and ejector-type explosion-proof valves. Both of the above explosion-proof valves will deform and displace during use as the thermal runaway process of the battery develops. Therefore, after making adaptive adjustments, for example, after adaptively adjusting the setting position of the displacement sensor according to the different structures of the explosion-proof valves, they can be applied to the battery protection method of the present application.
[0073] On the basis of the above technical solution, according to the second aspect of the present application, a battery protection system is provided, which is applicable to the above battery protection method. The battery protection system may include a displacement sensor, a protection device and an industrial computer. The displacement sensor is arranged at the position of the battery explosion-proof valve to detect the displacement of the explosion-proof valve. The protection device is arranged on the side of the battery pack explosion-proof valve for isolation protection before the explosion of the explosion-proof valve. The industrial computer is electrically connected to the displacement sensor and the protection device respectively, and the displacement sensor detects data and transmits it to the industrial computer. The industrial computer can control the cutting off of the power supply of the battery pack. At the same time, the industrial computer can control the movement of the protection device to the position of the explosion-proof valve to isolate and protect it.
[0074] Based on the above-mentioned embodiments of the present application, through the setting of the above-mentioned battery protection system, when the battery is in use, the displacement sensor is used to detect the time when the battery explosion-proof valve will burst, that is, the threshold value at which the battery explosion-proof valve will burst. When the explosion is about to occur, the industrial computer is used to control the battery power supply to be cut off to avoid damage to other components. At the same time, the industrial computer controls the protection device to isolate and protect the explosion-proof valve position to avoid affecting other single batteries.
[0075] In addition, it should be noted that the battery protection system provided by the present application is not limited to the above structure. For example, a pressure sensor is also provided to detect the pressure value of the explosion-proof valve while setting the displacement sensor, and the accuracy of the detection is further improved by cooperating and verifying the two sets of data.
[0076] For another example, a separate insulation layer may be provided in the protection device to insulate the high-temperature flue gas released from the explosion-proof valve, and control the impact of the high-temperature flue gas within the protection device as much as possible, thereby minimizing the impact on other single cells when thermal runaway of a single cell occurs and the explosion-proof valve bursts, thereby improving overall safety.
[0077] Based on the above basic scheme, according to the third aspect of the present application, a battery pack is provided, which includes a plurality of single cells and the above battery protection system. An explosion-proof valve is provided on the single cell, a displacement sensor is connected to the explosion-proof valve, and a protection device is provided on the side of the explosion-proof valve.
[0078] Based on the above-mentioned embodiments of the present application, the battery pack provided in the present application includes the above-mentioned battery protection system, and therefore also has the above-mentioned beneficial effects. In order to avoid repetition, they will not be described here.
[0079] The preferred embodiments of the present application are described in detail above in conjunction with the accompanying drawings; however, the present application is not limited to the specific details in the above embodiments. Within the technical concept of the present application, a variety of simple modifications can be made to the technical solution of the present application, and these simple modifications all fall within the protection scope of the present application.
[0080] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this application will not further describe various possible combinations.
[0081] In addition, the various implementation modes of the present application may be arbitrarily combined, and as long as they do not violate the concept of the present application, they should also be regarded as the contents disclosed in the present application.
Claims
1. A battery protection method, characterized in that: The battery protection method comprises the following steps: Conduct simulation test on deformation and displacement of explosion-proof valve of single battery under thermal runaway condition; Determine the safe displacement of the explosion-proof valve under thermal runaway conditions based on simulation test results; A displacement sensor is provided at the battery explosion-proof valve to detect the displacement change of the explosion-proof valve, and a protective device is provided at the same time; The displacement change data detected by the displacement sensor is transmitted to the industrial computer; When the displacement change is greater than or equal to the safe displacement, the industrial computer controls to cut off the power supply of the battery pack, and at the same time controls the protection device to perform isolation protection through the industrial computer.
2. The battery protection method according to claim 1, characterized in that: When simulating the deformation and displacement of the explosion-proof valve of a single battery, the simulation is performed by simultaneously inflating, pressurizing, and heating the battery housing.
3. The battery protection method according to claim 2, characterized in that: When pressurizing the battery housing, the initial pressure in the battery housing is P. As the pressurizing process proceeds, the pressure in the battery housing gradually increases, and 0.1Mpa≤P≤0.8Mpa.
4. The battery protection method according to claim 2, characterized in that: When heating is applied to the battery housing, the temperature inside the battery housing is T. As the heating process proceeds, the temperature T inside the battery housing gradually increases, and T≥25°C.
5. The battery protection method according to claim 1, characterized in that: The protection device and the explosion-proof valve are spaced apart at a distance L, 4mm≤L≤6mm.
6. The battery protection method according to claim 1, characterized in that: The industrial computer is pre-set with a safe displacement range of the explosion-proof valve. When the displacement variation detected by the displacement sensor is greater than the safe displacement, the industrial computer controls the protection device to isolate and protect the explosion-proof valve.
7. The battery protection method according to claim 1, characterized in that: The protection device is configured as a protection cover, and the protection cover can be arranged on the outer wall of the battery housing at the location of the explosion-proof valve.
8. A battery protection system, applicable to the battery protection method according to any one of claims 1 to 7, characterized in that: The battery protection system comprises: A displacement sensor is arranged at the battery explosion-proof valve to detect the displacement of the explosion-proof valve; A protection device, arranged on the side of the battery explosion-proof valve, for isolating and protecting the battery before the explosion-proof valve explodes; and The industrial computer is electrically connected to the displacement sensor and the protection device respectively. The displacement sensor detects data and transmits it to the industrial computer. The industrial computer can control the battery power supply to be cut off. At the same time, the industrial computer can control the protection device to move to the explosion-proof valve position to isolate and protect it.
9. The battery protection system according to claim 8, characterized in that: The industrial computer includes a control module and an action module. The displacement sensor is electrically connected to the control module. The control module can control the action module to drive the protection device to isolate and protect the explosion-proof valve.
10. A battery pack, characterized in that: The battery pack comprises: A plurality of single cells, each of which is provided with an explosion-proof valve; and According to the battery protection system as described in claim 8 or 9, the displacement sensor is connected to the explosion-proof valve, and the protection device is arranged on the side of the explosion-proof valve.