Battery management method and device, storage medium, electric device, battery, and system

Abstract

The present application discloses a battery management method and device, a storage medium, an electric device, a battery, and a system. The battery management method comprises: acquiring first center wavelength change data of an optical fiber sensor and second center wavelength change data of the optical fiber sensor, wherein the optical fiber sensor at least comprises a first mode and a second mode, a center wavelength in the first mode and a center wavelength in the second mode are respectively changed along with the temperature and the stress, the first center wavelength change data is generated in the charge change of a battery in the first mode, and the second center wavelength change data is generated in the charge change of the battery in the second mode; and on the basis of the first center wavelength change data and the second center wavelength change data, determining battery data of the charge change of the battery. Therefore, the adverse risks of the sudden decrease of the battery capacity, breakage of electrode sheets or battery cells and the like caused by abnormal battery data can be effectively mitigated, improving the safety performance of battery use.

Description

Battery management method, device, storage medium, power device, battery and system

[0001] This application claims priority to Chinese patent application number 2023115807173, filed on November 24, 2023, entitled “Battery management method, device, storage medium, electrical device, battery and system”, which is incorporated herein by reference in its entirety.

Technical field

[0002] The present application relates to the field of battery technology, and in particular to battery management methods, equipment, storage media, electrical devices, batteries, and systems. [Background Technology]

[0003] Energy conservation and emission reduction are key to sustainable development, promoting the adjustment of energy structure and driving the development and application of battery technology. The key to the development of battery technology lies in electrochemical energy storage technology. Due to its advantages such as high energy density, good cycle life, high operating voltage, environmental friendliness, and low self-discharge, it has been widely used in portable electronics, electric vehicles, and energy storage systems.

[0004] During use, the battery may become overheated or experience large expansion force, which may even exceed the maximum value allowed by the design, resulting in a drop in capacity, or rupture of the electrodes or cells. Therefore, relevant measures can be taken in a targeted manner by determining the changes in battery data.

[0005] [Summary of the invention]

[0006] The main purpose of this application is to provide a battery management method, equipment, storage medium, power device, battery and system, aiming to solve the above-mentioned technical problems existing in the prior art.

[0007] To address the above-mentioned issues, the present application provides a battery management method, comprising: obtaining first central wavelength change data and second central wavelength change data of an optical fiber sensor; wherein the optical fiber sensor includes at least a first mode and a second mode, the central wavelength in the first mode and the central wavelength in the second mode change with temperature and stress, respectively; the first central wavelength change data is generated by the first mode when the battery is in a state of charge change, and the second central wavelength change data is generated by the second mode when the battery is in a state of charge change; and based on the first central wavelength change data and the second central wavelength change data, determining battery data of the battery's charge change. Thus, the optical fiber sensor has a first mode and a second mode, and the central wavelength in the first mode and the central wavelength in the second mode change with temperature and stress, respectively. Battery data of the battery in a state of charge change can be obtained using a single optical fiber sensor having the first mode and the second mode, alleviating the high cost problem caused by multiple optical fiber sensors. Furthermore, it can effectively mitigate the adverse risks of battery water leakage, electrode or cell rupture, and other adverse risks caused by abnormal battery data, thereby improving the safety performance of battery use.

[0008] In some embodiments, the step of determining battery data associated with battery charge variation based on the first and second center wavelength variation data includes: establishing a first relationship between the first center wavelength variation data and a first temperature coefficient and a first stress coefficient in a first mode; establishing a second relationship between the second center wavelength variation data and a second temperature coefficient and a second stress coefficient in a second mode; and solving the first and second relationships to obtain battery charge variation expansion force data and battery temperature data. Thus, by establishing the first and second relationships and solving the first and second relationships, battery charge variation expansion force data and battery temperature data can be quickly and accurately obtained, further preventing adverse consequences caused by excessive battery temperature and / or expansion force, and improving battery safety.

[0009] In some embodiments, the battery management method further includes issuing a thermal runaway warning if the battery temperature data is greater than or equal to a preset temperature threshold. This allows timely measures to mitigate the risk of thermal runaway caused by excessive battery temperature, thereby improving battery safety.

[0010] In some embodiments, after solving the first and second relationship equations to obtain battery charge-dependent expansion force data and battery temperature data, the battery management method further comprises: obtaining battery health data and the maximum expansion force under charge under the battery health data to obtain multiple sets of expansion force fitting data; performing curve fitting on the multiple sets of expansion force fitting data to obtain a battery expansion force variation equation; and determining the battery health state based on the expansion force variation equation. Thus, by fitting the multiple sets of expansion force fitting data to obtain a battery expansion force variation equation, the battery health state can be predicted based on the expansion force variation equation to perform battery risk assessment, thereby facilitating targeted battery management and improving battery safety.

[0011] In some embodiments, the step of determining the battery's state of health based on the expansion force variation equation includes: determining a predicted expansion force value for a first preset health value based on the expansion force variation equation; comparing the predicted expansion force value with an expansion force threshold corresponding to the first preset health value to obtain a first comparison result; and determining the battery's state of health based on the first comparison result. Thus, the predicted expansion force value for the first preset health value can be obtained using the expansion force variation equation, and the predicted expansion force value can be compared with the expansion force threshold to determine the battery's state of health. This allows for a simple prediction of the battery's state of health, facilitates targeted battery management, and improves battery safety.

[0012] In some embodiments, the step of determining the battery health state based on the first comparison result includes: if the predicted expansion force value is less than or equal to the corresponding expansion force threshold, determining that the battery is in a state where the expansion force is within the limit; and if the predicted expansion force value is greater than the corresponding expansion force threshold, determining that the battery is in a state where the expansion force is exceeded. Thus, the predicted expansion force value is compared with the expansion force threshold. If the predicted expansion force value is greater, the battery is determined to be in a state where the expansion force is exceeded, thus accurately concluding that the battery is in an unhealthy state. If the predicted expansion force value is smaller, the battery is determined to be in a state where the expansion force is within the limit, thus accurately concluding that the battery is in a healthy state. This facilitates targeted battery management and improves battery safety.

[0013] In some embodiments, the step of determining the battery's state of health based on the expansion force variation equation includes: determining the rate of change of the expansion force variation equation at a second preset health value; comparing the rate of change with a preset rate of change threshold to obtain a second comparison result; and determining the battery's lithium deposition state based on the second comparison result. Thus, by determining the rate of change of the expansion force variation equation at the second preset health value and comparing the rate of change with the preset rate of change threshold to determine the battery's lithium deposition state, the battery's lithium deposition state can be determined in a simple manner, facilitating targeted battery management and improving battery safety.

[0014] In some embodiments, the step of determining the lithium deposition state of the battery based on the second comparison result includes: if the rate of change is less than or equal to a preset rate of change threshold, determining that the battery is in a non-lithium deposition state; if the rate of change is greater than the preset rate of change threshold, determining that the battery is in a lithium deposition state. Thus, the rate of change is compared with the preset rate of change threshold. When the rate of change is greater, it is determined that the battery is in a lithium deposition state, i.e., accurately concluding that the battery is in an unhealthy state. When the rate of change is smaller, it is determined that the battery is in a non-lithium deposition state, i.e., accurately concluding that the battery is in a healthy state. This facilitates targeted battery management and improves battery safety.

[0015] To solve the above problems, the present application provides a battery management device, which includes a processor and a memory. The memory stores a computer program, and the processor is used to execute the computer program to implement the above battery management method.

[0016] To solve the above problems, the present application provides a computer-readable storage medium having program instructions stored thereon, which implement the above battery management method when the program instructions are executed by a processor.

[0017] To solve the above problems, the present application provides a battery system, which includes a battery cell, an optical fiber sensor and a battery management device. The optical fiber sensor has at least two modes, and the battery management device is used to execute the above battery management method.

[0018] To address the above-mentioned issues, the present application provides a battery comprising: a housing, a fiber optic sensor, and a battery management device. The fiber optic sensor is disposed within the housing and has a first mode and a second mode. The central wavelength in the first mode and the central wavelength in the second mode change with temperature and stress, respectively. The battery management device is connected to the fiber optic sensor and is configured to determine battery data based on the central wavelength in the first mode and the central wavelength in the second mode. Thus, the fiber optic sensor has a first mode and a second mode, and a single fiber optic sensor can be used to obtain battery data as the battery changes in charge. This alleviates the high cost associated with multiple fiber optic sensors and effectively mitigates adverse risks such as battery water leakage, electrode or cell rupture, and other adverse risks caused by abnormal battery data, thereby improving the safety of battery use.

[0019] In some embodiments, the optical fiber sensor includes a tilted Bragg grating optical fiber sensor. Thus, a single optical fiber sensor can be used to decouple and monitor the battery temperature and expansion force during use in real time, thereby reducing costs and manufacturing difficulty.

[0020] In some embodiments, the battery further includes an optical demodulator, which is communicatively coupled to the battery management device and configured to transmit light to the fiber optic sensor and receive light returned from the fiber optic sensor. Thus, the optical demodulator can demodulate the light and convert the optical signal into an electrical signal, enabling the battery management device to obtain battery data based on the relevant data.

[0021] In some embodiments, the battery further includes a circulator, wherein the optical fiber sensor is configured to reflect a portion of the light to the optical demodulator and transmit a portion of the light to the circulator, and the circulator is configured to reflect the portion of the light transmitted by the optical fiber sensor back to the optical demodulator. Thus, by providing the circulator to reflect the portion of the transmitted light to the optical demodulator, the optical demodulator can simultaneously receive and demodulate two light beams, thereby improving the demodulation efficiency of the optical demodulator and facilitating the battery management device to obtain battery data based on the relevant data.

[0022] In order to solve the above problems, the present application provides an electrical device, which includes the above-mentioned battery.

Brief Description of the Drawings

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] FIG1 is a schematic structural diagram of a vehicle according to one or more embodiments;

[0025] FIG2 is a schematic diagram of an exploded structure of a battery pack according to one or more embodiments;

[0026] FIG3 is a first structural schematic diagram of a battery according to one or more embodiments;

[0027] FIG4 is a schematic diagram showing a change in the central wavelength of an optical fiber sensor according to one or more embodiments;

[0028] FIG5 is a second structural diagram of a battery according to one or more embodiments;

[0029] FIG6 is a flow chart of a battery management method according to one or more embodiments;

[0030] FIG7 is a flowchart illustrating a method for determining a battery health state according to one or more embodiments;

[0031] FIG8 is a schematic diagram of a structure according to one embodiment of one or more battery systems;

[0032] FIG9 is a schematic diagram of the structure of one or more battery management devices according to an embodiment;

[0033] FIG10 is a block diagram of an embodiment of a computer storage medium according to one or more embodiments. [Specific implementation method]

[0034] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0036] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0037] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0038] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0039] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0040] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do 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 the embodiments of the present application.

[0041] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0042] Currently, market developments indicate that batteries are increasingly being used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As battery applications continue to expand, market demand is also growing.

[0043] Batteries mentioned in this field can be categorized as either primary batteries or rechargeable batteries, depending on whether they are rechargeable. Primary batteries are also called "disposable" batteries or primary batteries because once they are depleted, they cannot be recharged and must be discarded. Rechargeable batteries are also called secondary batteries, secondary batteries, or storage batteries. Rechargeable batteries are manufactured using different materials and processes than primary batteries. Their advantage is that they can be reused multiple times after charging, and their output current capacity is higher than that of most primary batteries. Common types of rechargeable batteries include lead-acid batteries, nickel-metal hydride batteries, and lithium-ion batteries. Lithium-ion batteries offer advantages such as light weight, high capacity (1.5 to 2 times that of nickel-metal hydride batteries of the same weight), no memory effect, and a very low self-discharge rate. Consequently, despite their relatively high price, they are widely used. Lithium-ion batteries are also widely used in pure electric vehicles and hybrid vehicles. While the capacity of lithium-ion batteries used for these applications is relatively low, they offer high output, high charging current, and a long service life, albeit at a higher cost.

[0044] The batteries described in the embodiments of this application are either rechargeable batteries or disposable batteries. The embodiments disclosed herein will be described primarily using lithium-ion batteries as an example. It should be understood that the embodiments disclosed herein are applicable to any other suitable type of rechargeable battery. The batteries described in the embodiments disclosed herein can be directly or indirectly used in appropriate devices to power such devices.

[0045] The present application provides an electrical device, which may include but is not limited to mobile phones, tablets, laptops, electric toys, electric tools, battery-powered vehicles, electric cars, ships, spacecraft, and the like. The electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the spacecraft may include airplanes, rockets, space shuttles, and spacecraft. The electrical device may include a battery, which may provide electrical energy to the device to achieve corresponding functions.

[0046] The present application also provides an electric vehicle, which may include a battery pack.

[0047] Please refer to FIG. 1 , which is a schematic structural diagram of a vehicle according to one or more embodiments.

[0048] Vehicle 1 can be a fuel-powered vehicle, a gas-powered vehicle, or a new energy vehicle. The latter can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle. Vehicle 1 is internally provided with a battery pack 2, which can be located at the bottom, front, or rear of vehicle 1. Battery pack 2 can be used to power vehicle 1, for example, as an operating power source for vehicle 1. Vehicle 1 also includes a controller 3 and a motor 4. Controller 3 controls battery pack 2 to power motor 4, for example, to meet the power requirements of vehicle 1 for starting, navigation, and driving.

[0049] In some embodiments of the present application, the battery pack 2 can serve not only as the operating power source of the vehicle 1, but also as the driving power source of the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0050] In order to improve the performance of electrical devices, the present application also provides a battery pack. See FIG2 , which is a schematic diagram of the exploded structure of a battery pack according to one or more embodiments.

[0051] The shape of the battery pack may include but is not limited to a square, cylindrical, or other arbitrary shapes.

[0052] In some embodiments, the battery pack 2 may include a case 20 and a battery 10, with the battery 10 contained within the case 20. The case 20 is used to provide a storage space for the battery 10, and the case 20 may adopt a variety of structures. In some embodiments, the case 20 may include a first portion 21 and a second portion 22, the first portion 21 and the second portion 22 covering each other, and the first portion 21 and the second portion 22 jointly defining a storage space for accommodating the battery 10. The second portion 22 may be a hollow structure with one end open, and the first portion 21 may be a plate-like structure, with the first portion 21 covering the open side of the second portion 22, so that the first portion 21 and the second portion 22 jointly define a storage space; the first portion 21 and the second portion 22 may also be hollow structures both with one side open, with the open side of the first portion 21 covering the open side of the second portion 22.

[0053] The battery 10 may include battery cells. Within the battery pack 2, there may be multiple battery cells, which may be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a combination of series and parallel connections. Multiple battery cells may be directly connected in series, in parallel, or in a hybrid configuration, and then the entire structure of the multiple battery cells is housed within the housing 20. Alternatively, the battery pack 2 may comprise multiple battery cells connected in series, in parallel, or in a hybrid configuration to form a battery module, which is then connected in series, in parallel, or in a hybrid configuration to form a single unit housed within the housing 20. The battery pack 2 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells.

[0054] Battery cell production methods include laminated and wound methods. Laminated batteries offer uniform current collection, low internal resistance, and high specific power. However, to achieve high precision, they require extremely high mold accuracy, high equipment investment, and a complex process, resulting in low production efficiency. Wound batteries are simple to produce, with moderate equipment precision requirements during the production and assembly processes. They offer high production efficiency and low costs. In terms of performance, wound batteries offer excellent high and low temperature resistance, rapid charging, an extremely long lifespan, stable high output voltage, a sturdy structure, and strong shock resistance.

[0055] The battery 10 may also include battery cells and other functional components. For example, the battery 10 may also include a control chip and / or a sensor, etc.

[0056] However, the battery data of the battery 10 will continue to change during use. For example, the battery temperature may be too high or the battery expansion force may be too large, which may even exceed the maximum value allowed by the design, thereby causing the capacity to drop or the electrode or battery cell to rupture. Therefore, relevant measures can be taken in a targeted manner by determining the changes in the battery data.

[0057] In order to solve the technical problems existing in the relevant embodiments, the present application provides a battery. See FIG3 , which is a first structural schematic diagram of a battery according to one or more embodiments.

[0058] The battery 10 includes a housing 100, a fiber optic sensor 200 and a battery management device 300. The fiber optic sensor 200 is arranged in the housing 100. The central wavelength of the fiber optic sensor 200 can change with temperature and stress. The battery management device 300 can collect relevant data on the change of the central wavelength of the fiber optic sensor 200, etc.

[0059] The outer shell 100 may be formed with a space for accommodating bare cells and other functional components. Specifically, the outer shell 100 may include an end cap and a shell. The end cap refers to a component that covers the opening of the shell to isolate the internal environment of the shell from the external environment. Without limitation, the shape of the end cap can be adapted to the shape of the shell to match the shell. Optionally, the end cap can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap is not easily deformed when squeezed or collided, so that the battery cell can have a higher structural strength and improved safety performance. Functional components such as electrode terminals may be provided on the end cap. The electrode terminal can be used to electrically connect to the bare cell for outputting or inputting electrical energy of the battery 10. In some embodiments, the electrode terminal may include a pole. The pole may include a positive pole and a negative pole for outputting current and connecting to an external circuit. In some embodiments, the end cap may also be provided with an explosion-proof component for releasing internal pressure when the internal pressure or temperature of the battery cell reaches a threshold. The end cap can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, and plastic, and this is not particularly limited in the present embodiment. In some embodiments, an insulating member can be provided on the inner side of the end cap to isolate the electrical connection components within the housing from the end cap to reduce the risk of short circuits. Exemplary insulating members can be plastic, rubber, and the like.

[0060] The shell is a component used to cooperate with the end cap to form the internal environment of the battery cell, wherein the formed internal environment can be used to accommodate bare cells, electrolytes and other components. The shell and the end cap can be independent components, and an opening can be set on the shell, and the internal environment of the battery cell is formed by covering the opening with the end cap at the opening. Without limitation, the end cap and the shell can also be integrated. Specifically, the end cap and the shell can form a common connection surface before other components are put into the shell, and when the interior of the shell needs to be encapsulated, the end cap is covered with the shell. The shell can be of various shapes and sizes, such as rectangular, cylindrical, hexagonal, etc. Specifically, the shape of the shell can be determined according to the specific shape and size of the electrode assembly. The material of the shell can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose special restrictions on this.

[0061] The optical fiber sensor 200 is a multi-mode optical fiber sensor. Specifically, the optical fiber sensor 200 has at least a first mode and a second mode. The central wavelength in the first mode and the central wavelength in the second mode change with temperature and stress, respectively.

[0062] For example, in the spectrum diagram of some typical tilted Bragg grating fiber sensors, there are multiple peaks, each peak represents a mode, and the types of modes can be divided into core mode (fiber core mode), ghost mode (ghost mode) and cladding mode. The above-mentioned first mode and second mode can be any two modes selected from them.

[0063] 4 , which is a schematic diagram illustrating changes in the center wavelengths of two modes of an optical fiber sensor according to one or more embodiments.

[0064] In this embodiment, the optical fiber sensor 200 has at least two modes. The solid line in the figure represents the center wavelength in the first mode, and the dashed line represents the center wavelength in the second mode. In the first mode, the initial center wavelength of the optical fiber sensor 200 is λ11. When the optical fiber sensor 200 is affected by external factors, its center wavelength in the first mode will change accordingly. For example, when the optical fiber sensor 200 is affected by temperature and / or stress, its center wavelength will shift from λ11 to λ12. The change in the center wavelength of the optical fiber sensor 200 is the difference between λ11 and λ12. In the second mode, the initial center wavelength of the optical fiber sensor 200 is λ21. When the optical fiber sensor 200 is affected by external factors, its center wavelength in the second mode will shift accordingly. For example, when the optical fiber sensor 200 is affected by temperature and / or stress, its center wavelength will shift from λ21 to λ22. The change in the center wavelength of the optical fiber sensor 200 is the difference between λ21 and λ22.

[0065] The battery management device 300 is connected to the optical fiber sensor 200. The battery management device 300 can be located inside or outside the housing 100. The battery management device 300 can be a battery management system (BMS), or a battery management unit (BMU) of a battery management system, or a controller such as a central control platform of a vehicle or energy storage system. A battery management device 300 can act on one or more battery cells at the same time. The battery management device 300 can be connected to the optical fiber sensor 200 for communication. For example, the battery management device 300 can be directly connected to the optical fiber sensor 200 for wired communication, or the optical fiber sensor 200 can be connected to other devices, and the battery management device 300 can be connected to the other devices for wired or wireless communication, etc. Among them, wireless communication can include Bluetooth communication, radio frequency communication, or optical communication, etc.

[0066] The battery management device 300 is used to determine battery data based on the central wavelength in the first mode and the central wavelength in the second mode. Battery data includes, but is not limited to, expansion force data and battery temperature data. The optical fiber sensor 200 is located within the housing 100. Factors that significantly influence the central wavelength of the optical fiber sensor 200 include changes in battery temperature and battery stress. These changes are primarily caused by the battery 10's charge and discharge processes. Changes in battery stress are primarily caused by the expansion of the battery 10 after use. Once the battery management device 300 determines the central wavelength in the first mode and the central wavelength in the second mode, it determines battery data based on the different effects of temperature and stress on the central wavelength in the two modes.

[0067] Through the above-mentioned embodiment, the optical fiber sensor 200 has a first mode and a second mode, and the battery data of the battery 10 during charge changes can be obtained through one optical fiber sensor 200, thereby alleviating the high cost problem caused by multiple optical fiber sensors 200, and can also effectively alleviate the adverse risks such as battery 10 diving, pole piece or battery cell rupture due to abnormal battery data, thereby improving the safety performance of the battery 10.

[0068] Furthermore, the optical fiber sensor 200 includes a tilted Bragg grating optical fiber sensor. The tilted Bragg grating optical fiber sensor may include a cladding and a core, wherein the cladding is coated on the outside of the core, and the radial dimension of the cladding may be less than or equal to 125 μm, for example, the radial dimension of the cladding may be 50 μm, 40 μm, 30 μm, 60 μm, 55 μm, 45 μm, etc.

[0069] The basic principle of a tilted Bragg grating fiber sensor is to create a grating region with a periodic refractive index distribution at a specific location on the optical fiber. This grating region is tilted relative to the fiber core, and the tilt angle can range from 1° to 45°. When light is incident on the fiber sensor 200, light waves of specific wavelengths will be reflected by the grating region, while light waves of some wavelengths will be transmitted. The transmitted light can form at least two modes of the fiber sensor 200. The length of the grating region is not limited and can be between 0.1 cm and 1 cm. The transmitted center wavelength signal is related to the grating period and the effective refractive index of the fiber core. When the temperature, structure, or position of the sensed material changes, the grating period or the effective refractive index of the core membrane will change, thereby changing the center wavelength of at least two modes of the fiber sensor 200. As a result, battery data of the battery 10 during charge changes can be obtained using a single fiber sensor 200, alleviating the high cost problem caused by multiple fiber sensors 200.

[0070] Referring to FIG. 5 , FIG. 5 is a second structural schematic diagram of a battery according to one or more embodiments.

[0071] The battery 10 also includes an optical demodulator 400, which is communicatively connected to the battery management device 300. The optical demodulator 400 is used to emit light to the fiber optic sensor 200 and receive light transmitted back from the fiber optic sensor 200. The optical demodulator 400 can be used to convert the optical signal collected by the fiber optic sensor 200 into an electrical signal for collection and processing by the battery management device 300. For example, the optical demodulator 400 may include a light source, a photodetection unit, and a signal processing unit. The light source can be used to emit broad-spectrum light from one end of the optical fiber to the grating region of the fiber optic sensor 200, and then transmit it out from the other end of the optical fiber. In this case, the transmitted light contains the battery data information. The photodetection unit of the optical demodulator 400 receives the transmitted light, converts the transmitted signal light into an electrical signal, and processes the electrical signal through the signal processing unit for transmission to the battery management device 300. Thus, the transmitted light can be read by the optical demodulator 400 and the optical signal can be converted into an electrical signal, so that the battery management device 300 can obtain the battery data according to the relevant data.

[0072] Furthermore, the battery 10 further includes a circulator 500. The optical fiber sensor 200 is configured to reflect a portion of the light to the optical demodulator 400 and transmit a portion of the light to the circulator 500. The circulator 500 is configured to transmit the portion of the light transmitted by the optical fiber sensor 200 to the optical demodulator 400. The circulator 500 may be an optical fiber circulator 500, which is primarily configured to implement bidirectional optical signal transmission on a single optical fiber. The circulator 500 may be located at the rear end of the optical fiber sensor 200. A portion of the light from the optical fiber sensor 200 is reflected to be received by the optical demodulator 400, while the remaining portion of the light may transmit the optical fiber sensor 200 and be emitted from the rear end of the optical fiber sensor 200 to the circulator 500. The circulator 500 transmits the light emitted from the rear end of the optical fiber sensor 200 to the optical demodulator 400 for reception. In other embodiments, the fiber optic sensor 200 itself can be modified to replace the function of the circulator 500. Specifically, a reflective coating can be provided on the end face of the fiber optic sensor 200, such as a layer of SiO2, silver, or gold deposited on the end face. The highly reflective properties of the coating can be used to reflect the light transmitted by the fiber optic sensor 200, which carries the battery information, and transmit it back along the original path to the optical demodulator 400. The reflective coating eliminates the need to re-export the fiber optic sensor 200 end from the battery, nor does it require a circulator to connect the fiber end to receive and transmit the transmitted signal, thereby reducing production difficulty and device cost.

[0073] In some embodiments, the battery 10 may include an electrode assembly disposed within the housing 100, with the optical fiber sensor 200 connected to the electrode assembly. The electrode assembly is the component within the battery 10 where electrochemical reactions occur. The housing 100 may contain one or more electrode assemblies. The electrode assembly is primarily formed by winding or stacking positive and negative electrode sheets, typically with a separator between the positive and negative electrodes. The portions of the positive and negative electrodes containing active material constitute the main body of the electrode assembly, while the portions of the positive and negative electrodes without active material each constitute a tab. The positive and negative tabs may be located together at one end of the main body or separately at opposite ends. During the charge and discharge process of the battery 10, the positive and negative active materials react with the electrolyte, and the tabs connect to the electrode terminals to form a current circuit. As a crucial component of the battery 10, the electrode assembly is susceptible to high temperatures and significant stress concentration in certain locations after long-term use. This can lead to difficulties in electrolyte infiltration, circuit breaker, and even lithium deposition and electrode fracture.

[0074] Furthermore, the electrode assembly may be arranged to cover at least a portion of the optical fiber sensor 200, or at least a portion of the optical fiber sensor 200 may be connected to the outer surface of the electrode assembly. The electrode assembly may be wound or stacked. For example, when the electrode assembly is wound, the optical fiber sensor 200 may be located at the initial winding position of the electrode assembly, or at the middle position of the winding of the electrode assembly, or at the outer surface of the electrode assembly. For example, when the electrode assembly is stacked, the optical fiber sensor 200 may be located inside or outside the electrode assembly. Specifically, the optical fiber sensor 200 may be located on the surface of the larger surface of the electrode assembly or at a side corner.

[0075] To address the technical issues in the related embodiments, this application provides a battery management method, which can be applied to the batteries of any of the above embodiments. Referring to FIG6 , FIG6 is a flowchart of the battery management method according to one or more embodiments. Specifically, the method includes the following steps S601 to S602.

[0076] Step S601: Acquire first center wavelength variation data of the optical fiber sensor and second center wavelength variation data of the optical fiber sensor.

[0077] The optical fiber sensor has at least two modes, specifically a first mode and a second mode. The central wavelengths in the first mode and the second mode change with temperature and stress, respectively. Data on the first and second central wavelength changes can be obtained through detection. As shown in Figure 4, the solid line represents the central wavelength in the first mode, and the dashed line represents the central wavelength in the second mode. In the first mode, the optical fiber sensor's initial central wavelength is λ11. When the optical fiber sensor is affected by external factors, its central wavelength in the first mode changes accordingly. For example, when the optical fiber sensor is affected by temperature and / or stress, its central wavelength changes from λ11 to λ12. The change in the central wavelength of the optical fiber sensor is the difference between λ11 and λ12. In the second mode, the optical fiber sensor's initial central wavelength is λ21. When the optical fiber sensor is affected by external factors, its central wavelength in the second mode changes accordingly. For example, when the optical fiber sensor is affected by temperature and / or stress, its central wavelength changes from λ21 to λ22. The change in the central wavelength of the optical fiber sensor is the difference between λ21 and λ22.

[0078] The first center wavelength variation data is generated during the first mode when the battery changes charge, and the second center wavelength variation data is generated during the second mode when the battery changes charge. Battery SOC, or state of charge, reflects the remaining capacity of a battery. Its numerical value is defined as a ratio of the battery capacity and is often expressed as a percentage. For example, 100% SOC indicates a fully charged battery, while 0% SOC indicates a fully discharged battery. During the charging or discharging process, the battery SOC changes, meaning the battery undergoes a charge change. The internal state of the battery (such as its internal temperature and expansion force) changes with the battery's charge. For example, during continuous charging, the internal temperature of the battery increases. As the battery changes from one charge value to another, the internal state of the battery changes, thereby affecting the center wavelength in the first mode and the center wavelength in the second mode, respectively. For example, after charging a battery from 0% SOC to 100% SOC, both the battery temperature and expansion force change.

[0079] Step S602: Determine battery data of battery charge change based on the first center wavelength change data and the second center wavelength change data.

[0080] Battery data includes but is not limited to expansion force data, battery temperature data, etc. First center wavelength variation data is generated in a first mode, and second center wavelength variation data is generated in a second mode. Since the first mode and the second mode are different modes of the same optical fiber sensor, the factors affecting the variation of the first center wavelength and the factors affecting the variation of the second center wavelength are the same. By measuring the wavelength variation patterns of the first mode and the second mode, a matrix can be established, and then the battery data can be obtained by analyzing the matrix.

[0081] Through the above implementation, the optical fiber sensor has a first mode and a second mode, and the battery data of the battery during charge change can be obtained through a single optical fiber sensor, thereby alleviating the high cost problem caused by multiple optical fiber sensors. It can also effectively alleviate adverse risks such as battery diving, electrode or cell rupture due to abnormal battery data, thereby improving the safety performance of battery use.

[0082] Furthermore, based on the first center wavelength change data and the second center wavelength change data, the step of determining the battery data of the battery charge change includes: establishing a first relationship between the first center wavelength change data and the first temperature coefficient and the first stress coefficient in the first mode; establishing a second relationship between the second center wavelength change data and the second temperature coefficient and the second stress coefficient in the second mode; solving the first relationship and the second relationship to obtain the expansion force data and battery temperature data of the battery charge change.

[0083] Specifically, the first relationship can be the following calculation formula: δλ1=K1F *F+K 1T *T

[0084] Among them, δλ1 represents the first central wavelength change data, K 1F represents the first stress coefficient, K 1T represents the first temperature coefficient, F represents the expansion force data, and T represents the battery temperature data.

[0085] The second relationship can be expressed as follows: δλ2=K 2F *F+K 2T *T

[0086] Among them, δλ2 represents the second center wavelength change data, K 2F represents the second stress coefficient, K 2T represents the second temperature coefficient, F represents the expansion force data, and T represents the battery temperature data.

[0087] The first and second central wavelength variation data can be obtained through testing, and the first and second stress coefficients, first and second temperature coefficients can be obtained through experimentation. By combining the first and second relationship equations to form two linear equations, and solving these two linear equations, the expansion force data and battery temperature during battery charge variation can be obtained.

[0088] By establishing the first and second relationship equations and solving them through the above-described implementation, the battery charge-dependent expansion force data and battery temperature data can be quickly and accurately obtained. This can further prevent adverse consequences caused by excessive battery temperature and / or expansion force, thereby improving the safety performance of battery use.

[0089] Furthermore, the battery management method also includes: if the battery temperature data is greater than or equal to a preset temperature threshold, a thermal runaway warning is issued. The preset temperature threshold can be set according to actual conditions. For example, the preset temperature threshold is between 60°C and 75°C. Specifically, the preset temperature threshold is 60°C, 65°C, 70°C, 73°C or 75°C, etc. When the battery temperature is high, the battery may be at risk of thermal runaway, thereby issuing a thermal runaway warning to remind the user to perform preprocessing. Among them, the thermal runaway warning includes but is not limited to voice prompts, display prompts, etc. As a result, timely measures can be taken to alleviate the risk of thermal runaway due to excessively high battery temperature and improve the safety performance of battery use.

[0090] 7 , which is a schematic diagram of a process for determining a battery health status according to one or more embodiments, specifically, including the following steps S701 to S703 .

[0091] Step S701: obtaining battery health data of a battery and a maximum expansion force of a charge change under the battery health data, and obtaining multiple sets of expansion force fitting data.

[0092] Battery health data can be collected through battery management equipment. Battery health data (SOH) reflects the battery's health, that is, the percentage of the battery's fully charged capacity relative to its rated capacity. For example, the battery health of a new battery is 100% SOH, while the health of a retired power battery is generally 80% SOH. After long-term use, the battery's health gradually deteriorates. This deterioration in battery health affects the battery's expansion force at different states of charge. When the battery's health reaches a specific value, charging and discharging can be performed based on that specific value to obtain multiple expansion force data based on that specific value. The maximum expansion force value is selected from the multiple expansion force data, and the maximum expansion force data at that battery health level and the battery health level are combined as a set of expansion force fitting data. This step is repeated to obtain the maximum expansion force corresponding to different battery health levels, thereby obtaining multiple sets of expansion force fitting data. Exemplarily, when the battery health is 100% SOH, the battery is charged and discharged, and the expansion force is detected during the charging and discharging process to obtain the expansion force data when the health is 100% SOH, and then the maximum expansion force is selected from the expansion force data to obtain the maximum expansion force corresponding to the health of 100% SOH, and used as a set of expansion force fitting data; by analogy, when the battery health decreases to 99% SOH, the maximum expansion force corresponding to the battery health of 99% SOH is obtained; when the battery health decreases to (100-n)% SOH, the maximum expansion force corresponding to the health of (100-n)% SOH is obtained, thereby obtaining multiple sets of expansion force fitting data.

[0093] Step S702: performing curve fitting on multiple sets of expansion force fitting data to obtain an expansion force variation equation of the battery.

[0094] The multiple sets of expansion force fitting data may include: multiple sets of expansion force fitting data consisting of all battery health states and maximum expansion forces during the process of the battery health decreasing from one battery health state to another. By fitting the multiple sets of expansion force fitting data, an expansion force variation equation can be obtained with battery health as the independent variable and expansion force as the dependent variable. The battery expansion force variation equation can be used to predict the corresponding expansion force of the battery when the battery health reaches a specific value.

[0095] Step S703: Determine the health status of the battery based on the expansion force variation equation.

[0096] The health status of a battery may include, but is not limited to, whether the battery has an excessive expansion force, or whether the battery is experiencing lithium deposition, etc. After determining the expansion force variation equation, the expansion force data corresponding to the remaining battery health levels, as well as the slopes at different positions in the expansion force variation equation, can be obtained to determine the health status of the battery. As the battery health level changes, the expansion force variation equation can be updated in real time to more accurately determine the health status of the battery. Thus, by fitting multiple sets of expansion force fitting data, the battery's expansion force variation equation can be obtained, and the battery's health status can be predicted based on the expansion force variation equation to conduct a risk assessment of the battery, thereby facilitating targeted battery management and improving the safety of battery use.

[0097] In some embodiments, the step of determining the health state of the battery based on the expansion force change equation (step S703) includes: determining an expansion force prediction value of a first preset health value based on the expansion force change equation; comparing the expansion force prediction value with the expansion force threshold corresponding to the first preset health value to obtain a first comparison result; and determining the health state of the battery based on the first comparison result.

[0098] The first preset health value can be set based on actual conditions, for example, 80% SOH, 70% SOH, and so on. The first preset health value can also be determined based on the current battery health value. For example, if the current battery health value is 80% SOH, the first preset health value can be reduced by a preset decrease value of 1% SOH. That is, if the current battery health value is 80% SOH, the first preset health value is 79% SOH. After determining the first preset health value, the first preset health value can be directly substituted into the expansion force variation equation to obtain the predicted expansion force value corresponding to the first preset health value. The expansion force threshold can be set based on actual conditions. Different battery health levels can correspond to different expansion force thresholds. The expansion force threshold can be the maximum expansion force specification allowed by the corresponding battery health level. By comparing the predicted expansion force value with the corresponding expansion force threshold, the battery health state can be determined. This allows for a simple prediction of the battery health state, facilitating targeted battery management and improving battery safety.

[0099] Furthermore, the step of determining the health status of the battery based on the first comparison result includes: if the expansion force prediction value is less than or equal to the corresponding expansion force threshold, determining that the battery is in an expansion force within-limit state; if the expansion force prediction value is greater than the corresponding expansion force threshold, determining that the battery is in an expansion force exceeding-limit state.

[0100] For example, when the first preset state of health is 70% SOH, the corresponding expansion force threshold is F1, and the predicted expansion force value is F2. When F2 is greater than F1, it indicates that the battery's expansion force is within the limit when the battery health is at the first preset state of health. It can be predicted that the battery will be in a healthy state when the battery health drops to the first preset state of health. When F2 is less than F1, it indicates that the battery's expansion force is within the limit when the battery health is at the first preset state of health. It can be predicted that the battery will be in an unhealthy state when the battery health drops to the first preset state of health. This may lead to adverse risks such as battery leakage, electrode or cell rupture, etc. Therefore, the predicted expansion force value is compared with the expansion force threshold. If the predicted expansion force value is greater, it is determined that the battery is in an expansion force exceeding limit, thus accurately concluding that the battery is in an unhealthy state. If the predicted expansion force value is smaller, it is determined that the battery is in a healthy state, thus accurately concluding that the battery is in a healthy state. This facilitates targeted battery management and improves battery safety.

[0101] Optionally, the step of determining the health state of the battery based on the expansion force change equation (step S903) includes: determining the rate of change of the expansion force change equation at a second preset health value; comparing the rate of change with a preset rate of change threshold to obtain a second comparison result; and determining the lithium plating state of the battery based on the second comparison result.

[0102] The rate of change of the expansion force with the battery health can be obtained by differentiating the expansion force change equation. The second preset health value can be equal to the current health value of the battery, and the second preset value can be ≤95% SOH. After obtaining the second preset health value, the rate of change of the expansion force change equation at the second preset health value can be obtained by differentiating the expansion force change equation. The preset change rate threshold can be set according to actual conditions, and the preset change rate threshold corresponding to different battery healths may be different. By comparing the change rate with the corresponding preset change rate threshold, it can be determined whether the battery is in a lithium plating state. Therefore, by determining the change rate of the expansion force change equation at the second preset health value and comparing the change rate with the preset change rate threshold, the lithium plating state of the battery is determined, so that the lithium plating state of the battery can be judged in a simple way, which facilitates targeted management of the battery and improves the safety performance of battery use.

[0103] Furthermore, the step of determining the lithium deposition state of the battery based on the second comparison result includes: if the change rate is less than or equal to a preset change rate threshold, determining that the battery is in a non-lithium deposition state; if the change rate is greater than the preset change rate threshold, determining that the battery is in a lithium deposition state.

[0104] Exemplarily, when the second preset health value is 90% SOH, the corresponding rate of change is R1, and the corresponding preset rate of change threshold is R2. When R1 is greater than R2, it indicates that the battery is in a lithium deposition state when the battery health is the second preset health value, and it can be judged that the battery is in an unhealthy state when the battery health is reduced to the second preset health value. When R1 is less than R2, it indicates that the battery is in a non-lithium deposition state when the battery health is the second preset health value, and it can be judged that the battery is in a healthy state when the battery health is reduced to the second preset health value. In some embodiments, an intermediate rate of change threshold may also be included, and the intermediate rate of change threshold is greater than the preset rate of change threshold. When the rate of change is greater than the preset rate of change threshold and less than the intermediate rate of change threshold, the battery is in a mild lithium deposition state; when the rate of change is greater than the intermediate rate of change threshold, the battery is in a severe lithium deposition state. Therefore, the change rate is compared with the preset change rate threshold. When the change rate is large, it is determined that the battery is in a lithium deposition state, that is, it is accurately concluded that the battery is in an unhealthy state. When the change rate is small, it is determined that the battery is in a non-lithium deposition state, that is, it is accurately concluded that the battery is in a healthy state, which facilitates targeted management of the battery and improves the safety performance of battery use.

[0105] In order to solve the technical problems existing in the relevant embodiments, the present application provides a battery system. See Figure 8, which is a structural diagram according to an embodiment of one or more battery systems.

[0106] The battery system 600 includes a battery unit 101 , an optical fiber sensor 200 and a battery management device 300 . The optical fiber sensor 200 has at least two modes. The battery management device 300 is used to execute the battery management method of any of the above embodiments.

[0107] The battery unit 101 can be a battery cell or battery pack, or other energy storage element to be tested. The optical fiber sensor 200 can include, but is not limited to, a tilted Bragg grating optical fiber sensor. The battery management device 300 can be a battery management system (BMS), or a battery management unit (BMU) of a battery management system, or a controller such as a central control platform of a vehicle or energy storage system.

[0108] The battery management method of this embodiment can be applied to a battery management device. The battery management device of this application can be a server, a mobile device, or a system comprising a server and a mobile device. Accordingly, the various components of the mobile device, such as the various units, subunits, modules, and submodules, can be all located in the server, all located in the mobile device, or separately located in the server and the mobile device.

[0109] Furthermore, the server described above may be either hardware or software. When the server is hardware, it may be implemented as a distributed server cluster consisting of multiple servers, or as a single server. When the server is software, it may be implemented as multiple software programs or software modules, such as software or software modules for providing a distributed server, or as a single software program or software module, without further limitation.

[0110] In order to solve the technical problems existing in related embodiments, the present application provides a battery management device. Refer to Figure 9, which is a structural diagram of an embodiment of one or more battery management devices.

[0111] The battery management device 300 includes a processor 310 and a memory 320 . The memory 320 stores a computer program. The processor 310 is configured to execute the computer program to implement the battery management method of any of the above embodiments.

[0112] The processor 310 may be an integrated circuit chip with signal processing capabilities. The processor 310 may also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component. The general-purpose processor may be a microprocessor or any conventional processor.

[0113] The battery management method of the above embodiment can be presented in the form of a computer program. The present application proposes a computer storage medium that carries the computer program. Please refer to Figure 10, which is a structural diagram of an embodiment of a computer storage medium according to one or more embodiments.

[0114] The computer storage medium 700 of this embodiment includes a computer program 710 , which can be executed to implement the above-mentioned battery management method.

[0115] The computer storage medium 700 in this embodiment can be a medium that can store program instructions, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, or it can also be a server that stores the program instructions. The server can send the stored program instructions to other devices for execution, or it can also execute the stored program instructions itself.

[0116] In addition, if the above functions are implemented as software functions and sold or used as independent products, they can be stored in a storage medium readable by a mobile terminal. That is, the present application also provides a storage device storing program data, which can be executed to implement the methods of the above embodiments. The storage device can be, for example, a USB flash drive, an optical disk, a server, etc. In other words, the present application can be embodied in the form of a software product, which includes a number of instructions for causing a smart terminal to execute all or part of the steps of the methods described in each embodiment.

[0117] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present application belong.

[0118] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (which can be a personal computer, server, network device, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0119] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery management method, characterized in that: The battery management method comprises: Acquire first central wavelength change data of the optical fiber sensor and second central wavelength change data of the optical fiber sensor; wherein the optical fiber sensor includes at least a first mode and a second mode, the central wavelength in the first mode and the central wavelength in the second mode change with temperature and stress respectively, the first central wavelength change data is generated when the first mode changes during a battery charge change, and the second central wavelength change data is generated when the second mode changes during a battery charge change; Battery data of the battery charge change is determined based on the first center wavelength change data and the second center wavelength change data.

2. The battery management method according to claim 1, characterized in that: The step of determining the battery data of the battery charge change based on the first center wavelength change data and the second center wavelength change data comprises: Establishing a first relationship between the first central wavelength variation data and a first temperature coefficient and a first stress coefficient in the first mode; Establishing a second relationship between the second central wavelength variation data and the second temperature coefficient and the second stress coefficient in the second mode; The first relational expression and the second relational expression are solved to obtain the expansion force data of the battery charge change and the battery temperature data.

3. The battery management method according to claim 2, characterized in that: The battery management method further comprises: If the battery temperature data is greater than or equal to a preset temperature threshold, a thermal runaway warning is issued.

4. The battery management method according to any one of claims 1 to 3, characterized in that: The battery data includes expansion force data and battery temperature data, and the battery management method further includes: Acquire battery health data of the battery and a maximum expansion force of charge change under the battery health data to obtain multiple sets of expansion force fitting data; Performing curve fitting on the multiple sets of expansion force fitting data to obtain an expansion force variation equation of the battery; The health state of the battery is determined based on the expansion force variation equation.

5. The battery management method according to claim 4, characterized in that: The step of determining the health state of the battery based on the expansion force variation equation comprises: Determine the expansion force prediction value of the first preset health value based on the expansion force variation equation; Comparing the predicted expansion force value with the expansion force threshold corresponding to the first preset health value to obtain a first comparison result; A state of health of the battery is determined based on the first comparison result.

6. The battery management method according to claim 5, characterized in that: The step of determining the health status of the battery based on the first comparison result comprises: If the predicted expansion force value is less than or equal to the corresponding expansion force threshold, it is determined that the battery is in an expansion force within-limit state; If the predicted expansion force value is greater than the corresponding expansion force threshold, it is determined that the battery is in an expansion force exceeding limit state.

7. The battery management method according to claim 4, characterized in that: The step of determining the health state of the battery based on the expansion force variation equation comprises: Determining a rate of change of the expansion force change equation at a second preset health value; Comparing the change rate with a preset change rate threshold to obtain a second comparison result; The lithium plating state of the battery is determined based on the second comparison result.

8. The battery management method according to claim 7, characterized in that: The step of determining the lithium deposition state of the battery based on the second comparison result comprises: If the change rate is less than or equal to the preset change rate threshold, it is determined that the battery is in a non-lithium deposition state; If the change rate is greater than the preset change rate threshold, it is determined that the battery is in a lithium deposition state.

9. A battery management device, characterized in that: The battery management device comprises a processor and a memory, wherein a computer program is stored in the memory, and the processor is used to execute the computer program to implement the battery management method according to any one of claims 1 to 8.

10. A computer-readable storage medium having program instructions stored thereon, characterized in that: When the program instructions are executed by a processor, the battery management method according to any one of claims 1 to 8 is implemented.

11. A battery system, characterized in that: The battery system comprises a battery cell, an optical fiber sensor and a battery management device, wherein the optical fiber sensor has at least two modes, and the battery management device is used to execute the battery management method according to any one of claims 1 to 8.

12. A battery, characterized in that: The battery comprises: shell; The optical fiber sensor is arranged in the housing, and the optical fiber sensor has a first mode and a second mode, and the center of the first mode is The wavelength and the central wavelength in the second mode change with temperature and stress respectively; A battery management device is connected to the optical fiber sensor, and is used to determine battery data based on the central wavelength in the first mode and the central wavelength in the second mode.

13. The battery according to claim 12, characterized in that The optical fiber sensor comprises a tilted Bragg grating optical fiber sensor.

14. The battery according to claim 12 or 13, characterized in that: The battery further includes an optical demodulator, which is communicatively connected to the battery management device and is used to emit light to the optical fiber sensor and receive light returned by the optical fiber sensor.

15. The battery according to claim 14, characterized in that The battery further includes a circulator, the optical fiber sensor is used to reflect part of the light to the optical demodulator and transmit part of the light to the circulator, and the circulator is used to transmit part of the light transmitted by the optical fiber sensor to the optical demodulator.

16. An electrical device, characterized in that: The electrical device comprises the battery according to any one of claims 12 to 15.

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