Battery management system, single battery explosion-proof valve opening identification method and power supply equipment

Abstract

The invention discloses a battery management system, a single battery anti-explosion valve opening identification method and power supply equipment, electrolyte released after any anti-explosion valve is opened is directly captured through a plurality of concentration sensors, coverage monitoring of each single battery is realized, a controller sets a logic criterion of triggering early warning when the concentration of the electrolyte is greater than zero, and the battery anti-explosion valve opening identification method is realized. A complex algorithm is not needed, response is rapid, logic is clear, once any concentration sensor detects abnormity, a controller immediately outputs a starting signal to drive an early warning device to act, first-hand fault information is provided for operation and maintenance personnel, emergency disposal time is strived, leakage can be recognized in the initial stage of any single battery, and the safety of the battery is improved. The technical transition from passive response to active early warning is realized, and the timeliness of fault discovery is improved, so that the state of the explosion-proof valve of the single battery can be monitored in real time, the electrolyte leakage risk can be recognized in advance, and the operation safety, maintainability and reliability of a battery system are improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of battery energy storage, in particular to a battery management system, a single battery anti-explosion valve opening identification method and a power supply device. BACKGROUND

[0002] The lithium titanate battery has been widely applied to the fields with high reliability requirements such as new energy vehicles, rail transit and energy storage power stations due to its excellent cycle life, high-rate charge-discharge performance, wide temperature range adaptability and good safety. However, in the actual after-sales maintenance process, it is found that although the overall safety of the lithium titanate battery is high, there is still a problem of system-level failure caused by single battery failure.

[0003] The inventor's disassembly and analysis of a large number of after-sales failure battery boxes show that no matter whether the battery system has abnormal insulation resistance, the pressure difference between the single batteries in the box is too large, or the charging voltage is too high and the discharging voltage is too low (i.e. "high charging and low discharging"), the root cause of most of the failure phenomena can be traced back to that the anti-explosion valve of a single battery in the box has been opened, that is, local failure has occurred. It is worth noting that the lithium titanate battery has special electrochemical stability. In the early stage of the anti-explosion valve opening, although the electrolyte has leaked, the battery can still maintain normal charge-discharge function for a certain period of time and has not completely lost the use ability.

[0004] However, after the anti-explosion valve is opened, with the continuous operation of the single battery, the electrolyte continues to evaporate or seep out, the electrolyte and the positive and negative electrodes have a water absorption side reaction to cause damage, the performance of the single battery gradually deteriorates, which is manifested as voltage abnormality (the voltage rises too fast during charging and the voltage drops too fast during discharging), thereby causing the pressure difference in the battery pack to increase; at the same time, the leaked electrolyte may adhere to the battery shell or the box structure, causing the insulation resistance between the positive and negative electrodes or to the ground to decrease, eventually triggering the insulation failure alarm of the battery management system (BMS), forcing the system to shut down.

[0005] Under the existing technical conditions, the battery box is usually a closed structure, and the appearance state of each single battery inside cannot be observed in real time and directly. Since there is no obvious electrical parameter mutation in the early stage of the anti-explosion valve opening, the BMS is difficult to identify such a failure in time through the voltage, current, temperature and other conventional signals. Therefore, the abnormal opening of the anti-explosion valve of the single battery often needs to run for a long time after it occurs, and the system-level abnormality (such as pressure difference overrun and insulation alarm) is triggered, so that the maintenance personnel can be aware of it. At this time, the battery system must be stopped and disassembled for analysis, so as to locate the fault single battery, resulting in late failure discovery, high maintenance cost, large shutdown loss and serious influence on the usability and user trust of the battery system. SUMMARY

[0006] The application aims to provide a battery management system, a single battery explosion-proof valve opening identification method and a power supply device, which can monitor the state of the single battery explosion-proof valve in real time, identify the electrolyte leakage risk in advance, and improve the operation safety, maintainability and reliability of the battery system.

[0007] Embodiments of the application can be implemented as follows: In a first aspect, the application provides a battery management system, comprising a plurality of concentration sensors, a controller and a warning device, wherein the concentration sensors and the warning device are electrically connected to the controller. The plurality of concentration sensors are arranged in a battery box. The concentration sensors are configured to detect the electrolyte concentration in the explosion-proof valve area of one or more than one single battery, and send the electrolyte concentration to the controller. The controller is configured to obtain the electrolyte concentration from the concentration sensors, and send a start signal to the warning device if any of the electrolyte concentrations is greater than zero. The warning device is configured to issue a warning prompt when receiving the start signal.

[0008] In an optional embodiment, the controller is configured to send the start signal when the change amount of any of the electrolyte concentrations is greater than a preset threshold.

[0009] In an optional embodiment, each concentration sensor corresponds to the explosion-proof valve of one single battery.

[0010] In an optional embodiment, the concentration sensors and the controller are electrically connected by using an electromagnetic shielding cable.

[0011] In an optional embodiment, the electromagnetic shielding cable is wrapped with a corrosion-resistant material on the outside.

[0012] In a second aspect, the application provides a single battery explosion-proof valve opening identification method, comprising: Obtaining the electrolyte concentration in the explosion-proof valve area of one or more than one single battery in a battery box; Determining whether any of the electrolyte concentrations is greater than zero; If yes, a start signal is sent, which is used to control the warning device to issue a warning prompt.

[0013] In an optional embodiment, in the step of determining whether the electrolyte concentration is greater than zero, it is determined whether the change amount of any of the electrolyte concentrations is greater than a preset threshold.

[0014] In an optional embodiment, the step of obtaining the electrolyte concentration of the area of the explosion-proof valve on one or more than one single battery in the box includes obtaining the electrolyte concentration of the area of the explosion-proof valve on each single battery in the box.

[0015] In a third aspect, the application provides a power supply device, comprising a battery box and a battery management system according to any one of the preceding embodiments. The battery box comprises a box and a plurality of single batteries accommodated in the box, and the box is provided with a plurality of perforations. The concentration sensor is installed on the perforation through an interface sheet.

[0016] In an optional embodiment, the interface sheet and the box are filled with sealant.

[0017] The beneficial effects of the embodiments of the application include, for example: By arranging a plurality of concentration sensors to monitor the single batteries one-to-one or one-to-many, the electrolyte released after the opening of any explosion-proof valve is directly captured, the coverage monitoring of each single battery is realized, the controller sets the logic criterion that the electrolyte concentration greater than zero triggers the early warning, without complex algorithms, the response is rapid and the logic is clear, once any concentration sensor detects an anomaly, the controller immediately outputs a start signal to drive the alarm to act, providing the first-hand fault information for the operation and maintenance personnel to gain emergency disposal time, so that the initial stage of leakage of any single battery can be identified, realizing the technical leap from passive response to active early warning, and improving the timeliness of fault discovery, therefore, the application can monitor the state of the single battery explosion-proof valve in real time, identify the risk of electrolyte leakage in advance, and improve the operation safety, maintainability and reliability of the battery system. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the specific embodiments or prior art of the application, the drawings needed in the description of the specific embodiments or prior art will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0019] Figure 1 Flow chart of the single battery explosion-proof valve opening identification method according to the embodiments of the application. DETAILED DESCRIPTION

[0020] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0022] It should be noted that similar reference numerals and letters in the following drawings represent similar items, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.

[0023] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like 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 present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0024] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components must be absolutely horizontal or overhanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0025] In the description of the present application, it should also be noted that unless otherwise explicitly specified and limited, the terms "arrangement", "installation", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0026] Some embodiments of the present application will be described in detail with reference to the drawings. The following examples and features in the examples can be combined with each other in the case of no conflict.

[0027] The present application discloses an embodiment of a power supply device, which comprises a battery box and a battery management system; The battery box comprises a box body and a plurality of single batteries accommodated in the box body, and the box body is provided with a plurality of through holes; The battery management system comprises a plurality of concentration sensors, a controller and a warning device, and the concentration sensors and the warning device are electrically connected to the controller; The plurality of concentration sensors are distributed in the box body of the battery box, that is, one concentration sensor is installed in each through hole, and the concentration sensor is installed in the through hole through an interface sheet.

[0028] The concentration sensor is used to detect the electrolyte concentration of the explosion-proof valve area of one or more single batteries and send the electrolyte concentration to the controller; The controller is used to obtain the electrolyte concentration from the concentration sensor and send a start signal to the warning device in the case that any electrolyte concentration is greater than zero; The warning device is used to issue a warning prompt in the case of receiving the start signal.

[0029] As described above, by setting a plurality of concentration sensors at each through hole, one-to-one or one-to-many monitoring of single batteries is realized, the electrolyte released after opening of any explosion-proof valve is directly captured, coverage monitoring of each single battery is realized, the controller sets the logic criterion that the electrolyte concentration greater than zero triggers the warning, without complex algorithm, the response is rapid and the logic is clear, once any concentration sensor detects an abnormality, the controller immediately outputs a start signal to drive the warning device to act, providing first-hand fault information for the operation and maintenance personnel to strive for emergency disposal time, so that the initial stage of leakage of any single battery can be identified, realizing the technical leap from passive response to active warning, and improving the timeliness of fault discovery. Therefore, the present application can monitor the state of the explosion-proof valve of the single battery in real time, identify the risk of electrolyte leakage in advance, and improve the operation safety, maintainability and reliability of the battery system.

[0030] The interface sheet is also called a mounting flange sheet, a connecting sheet or a transition sheet, which refers to a metal or non-metal sheet structure for realizing mechanical connection, positioning and sealing cooperation between the concentration sensor box bodies, is fixed at the through hole of the box body, has a through hole in the center for installing the concentration sensor.

[0031] Due to the inevitable existence of a small assembly gap between the interface sheet and the box. If no sealing treatment is performed, the electrolyte gas released after the explosion-proof valve is opened may directly escape from such a gap to the outside of the box, bypassing the detection area of the concentration sensor, causing the system to fail to detect the leakage, resulting in a false alarm.

[0032] Therefore, in the present application, a sealant is filled between the interface sheet and the box. In this way, by filling the sealant, the small gap between the interface sheet and the box can be completely blocked, ensuring that all leaked gas is confined inside the box and preferentially passes through the sensor detection area, improving the integrity and reliability of the monitoring system.

[0033] In addition, the sealant not only prevents internal gas from escaping, but also prevents external moisture, dust, salt mist and other pollutants from entering the battery box through the installation gap, avoiding the intensification of internal side reactions of single batteries due to moisture intrusion, or causing problems such as reduced electrical insulation and corrosion of connecting parts, improving the long-term operation stability of the battery system.

[0034] The sealant can be made of electrolyte-resistant materials (such as fluorosilicone rubber, polyurethane, modified epoxy resin, etc.), which can resist the corrosion of organic solvents (such as dimethyl carbonate, ethylene carbonate) and strong corrosive by-products (such as hydrofluoric acid HF) for a long time, avoiding seal failure due to swelling, cracking or peeling of the glue layer, and ensuring reliable sealing performance under abnormal battery conditions.

[0035] The alarm can integrate high-brightness LED lights (such as red flashing) and high-decibel buzzers. Once the electrolyte concentration is detected to be abnormal, the audible and visual alarms are triggered immediately, allowing on-site maintenance personnel to quickly detect faults even in noisy or insufficient light environments without relying on background software queries, reducing response time and improving timeliness. In addition, if the alarm includes a small display screen or indicator panel, it can directly display text information such as "single cell leakage risk" and "explosion-proof valve opening warning", reducing the probability of false positives.

[0036] In addition, the alarm not only provides manual prompts, but also can be part of the control link, sending hard-wired or communication signals to the BMS to trigger automatic protection strategies, such as reducing charging and discharging power, cutting off the high-voltage circuit, starting the ventilation system or activating the fire extinguishing device.

[0037] It should be noted that different operating environments (such as temperature, humidity, altitude) or different battery aging stages may result in differences in background gas concentration. If only a fixed concentration of zero is used to determine a leak, false alarms may occur.

[0038] Therefore, in the present application, the controller is configured to issue a start signal when the change in any electrolyte concentration is greater than a predetermined threshold.

[0039] In this way, the comparison of the concentration change amount with the preset threshold value can exclude interference, adapt to different initial conditions, and ensure consistent early warning performance under various complex working conditions.

[0040] It can be understood that the preset threshold value can be dynamically adjusted according to historical operation data, battery type, environmental temperature, etc. For example, a lower initial threshold value is used in the new battery stage.

[0041] Each concentration sensor corresponds to the explosion-proof valve of a single battery. In this way, by configuring an independent concentration sensor for the explosion-proof valve of each single battery, each potential failure point is monitored exclusively, achieving full coverage of the single batteries in the battery box without missing monitoring, fundamentally eliminating monitoring dead angles, and improving system safety.

[0042] During the operation of the battery system, there are strong electromagnetic interference sources such as large current charging and discharging, relay action, BMS communication signals, and fan motor start-stop. The signal output by the concentration sensor is usually a weak electric signal of millivolt or microampere level, which is easily affected by electromagnetic interference and can produce false jumps. If this signal is misjudged by the controller as a sudden increase in concentration, it may trigger false alarms and affect the normal operation of the system. Conversely, if the interference signal masks the real leakage signal, it may lead to missed alarms and affect the normal operation of the system.

[0043] Therefore, an electromagnetic shielding cable is used for electrical connection between the concentration sensor and the controller. In this way, the cable with a shielding layer (such as copper mesh, aluminum foil, or double shielding) can effectively block the coupling interference of external electric and magnetic fields, suppress noise, and ensure that the signal received by the controller truly reflects the state of the single battery, improving the accuracy and reliability of the early warning system.

[0044] The outer side of the electromagnetic shielding cable is wrapped with a corrosion-resistant material (such as fluoroplastic (FEP / PFA), polyurethane (PU), cross-linked polyolefin, or silicone rubber), which can effectively block the intrusion of corrosive media and ensure that the shielding cable maintains its complete structure and electrical performance during long-term operation.

[0045] The application also discloses an embodiment of a single battery explosion-proof valve opening recognition method, which is described with reference to Figure 1 The method includes the following steps S1-S3: S1, obtaining the electrolyte concentration of the explosion-proof valve region of one or more than two single batteries in the box; S2, determining whether any electrolyte concentration is greater than zero; S3, if yes, issuing a start signal, and the start signal is used to control the early warning device to issue a warning prompt.

[0046] In the step S1 of acquiring the electrolyte concentration of the explosion-proof valve area on one or more than two single batteries in the box, the electrolyte concentration of the explosion-proof valve area on each single battery in the box is acquired, so that comprehensive coverage detection of all single batteries in the box is realized.

[0047] In the step S2 of judging whether the electrolyte concentration is greater than zero, whether the change amount of any electrolyte concentration is greater than a preset threshold is judged, so as to adapt to different initial conditions and ensure consistent early warning performance under various complex working conditions.

[0048] The controller is usually a central processing unit (CPU), and can be configured with a corresponding operating system, a control interface and the like. Specifically, the controller can be a digital logic control unit capable of being used for automatic control, such as a single-chip microcomputer, a digital signal processing (DSP), an advanced RISC machine (ARM) processor and the like. The control instructions can be loaded into the memory at any time for storage and execution. Meanwhile, the CPU instructions and data memory, input and output units, power modules, digital and analog units and the like can be built in. The actual use can be set, and the embodiments of the application do not limit this.

[0049] It should be noted that in several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are only schematic. For example, the flowcharts and block diagrams in the drawings show the possible implementation architectures, functions and operations of the devices, methods and computer program products according to the embodiments of the present application. In this regard, each block in the flowcharts or block diagrams can represent a module, a program segment or a part of code, which contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions noted in the blocks can occur in different orders from those noted in the drawings. For example, two consecutive blocks can actually be executed substantially in parallel, and sometimes they can be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and the combination of blocks in the block diagrams and / or flowcharts, can be implemented by a dedicated hardware-based system for executing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0050] It should be noted that, in the present text, the terms "comprises", "comprising", or any other variant thereof, are intended to cover the non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0051] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; even though the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can be made to the technical solutions recorded in the foregoing embodiments, or equivalent replacements can be made to some or all of the technical features; and these modifications or replacements do not cause the nature of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery management system, characterized by, The application relates to a battery management system comprising a plurality of concentration sensors, a controller and an early warning device, wherein the concentration sensors and the early warning device are electrically connected to the controller. The plurality of concentration sensors are distributed in a battery box. The concentration sensors are used for detecting the electrolyte concentration of the explosion-proof valve area of one or more than one single battery and sending the electrolyte concentration to the controller. The controller is used for acquiring the electrolyte concentration from the concentration sensors and sending a starting signal to the early warning device when any electrolyte concentration is greater than zero. The early warning device is used for sending an early warning prompt when the starting signal is received.

2. The battery management system of claim 1, wherein, The controller is used for sending the starting signal when the change of any electrolyte concentration is greater than a preset threshold.

3. The battery management system of claim 1, wherein, Each concentration sensor corresponds to the explosion-proof valve of one single battery.

4. The battery management system of claim 1, wherein, The concentration sensors and the controller are electrically connected by using electromagnetic shielding cables.

5. The battery management system of claim 4, wherein, The outer side of the electromagnetic shielding cables is wrapped by a corrosion-resistant material.

6. A method for identifying opening of an explosion vent of a single battery, characterized by, The application relates to a battery management system comprising a plurality of concentration sensors, a controller and an early warning device, wherein the concentration sensors and the early warning device are electrically connected to the controller. The application relates to a battery management system comprising a plurality of concentration sensors, a controller and an early warning device, wherein the concentration sensors and the early warning device are electrically connected to the controller. The application relates to a battery management system comprising a plurality of concentration sensors, a controller and an early warning device, wherein the concentration sensors and the early warning device are electrically connected to the controller. The application relates to a battery management system comprising a plurality of concentration sensors, a controller and an early warning device, wherein the concentration sensors and the early warning device are electrically connected to the controller.

7. The method of claim 6, wherein the method further comprises: The application relates to a battery management system comprising a plurality of concentration sensors, a controller and an early warning device, wherein the concentration sensors and the early warning device are electrically connected to the controller.

8. The method of claim 6, wherein the method further comprises: The application relates to a battery management system comprising a plurality of concentration sensors, a controller and an early warning device, wherein the concentration sensors and the early warning device are electrically connected to the controller.

9. A power supply device, characterized by comprising: The application relates to a battery management system comprising a plurality of concentration sensors, a controller and an early warning device, wherein the concentration sensors and the early warning device are electrically connected to the controller. The application relates to a battery management system comprising a plurality of concentration sensors, a controller and an early warning device, wherein the concentration sensors and the early warning device are electrically connected to the controller. The application relates to a battery management system comprising a plurality of concentration sensors, a controller and an early warning device, wherein the concentration sensors and the early warning device are electrically connected to the controller.

10. The power supply device according to claim 9, wherein ​

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