Battery cell assembly, battery monomer, battery and power utilization device

Abstract

The embodiment of the utility model provides a battery cell assembly, a battery monomer, a battery and a power utilization device. The battery cell assembly comprises a pole piece assembly, the optical fiber is provided with a sensor array, and sensors in the sensor array are all optical fiber sensors.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and more specifically, to a battery cell assembly, a battery cell, a battery, and an electrical device. Background Art

[0002] After long-term cycling of the battery, the battery cell may produce gas or expand, which may cause the battery cell to deform. If the battery cell deformation exceeds a certain degree, it may lead to serious battery cell safety accidents and create safety hazards.

[0003] In the prior art, strain gauges are usually installed on the outside of the battery to detect the degree of deformation of the battery cell. However, if the deformation of the battery cell is caused by gas production or expansion of the battery cell, the strain gauge installed on the outside of the battery will not detect it until the battery cell deformation accumulates to a certain extent. The deformation detection has a lag, resulting in low reliability of deformation detection. Summary of the Invention

[0004] The present application provides a battery cell assembly, a battery cell, a battery and an electrical device, which can improve the reliability of battery cell status detection.

[0005] In a first aspect, an embodiment of the present application provides a battery cell assembly, comprising:

[0006] Pole piece assembly;

[0007] An optical fiber is provided on the pole piece assembly, and the optical fiber is provided with a sensor array, and the sensors in the sensor array are all optical fiber sensors.

[0008] The battery cell assembly of the embodiment of the present application can detect the internal status information of the battery cell through the sensor array by arranging an optical fiber with an integrated sensor array on the pole piece assembly, thereby realizing real-time detection of the internal status of the battery cell and improving the reliability of the internal status detection of the battery cell.

[0009] In some embodiments, the sensor array includes at least one of the following: a strain sensor, a temperature sensor, and a pressure sensor.

[0010] The battery cell assembly of this embodiment enables real-time detection of the temperature, pressure, and deformation within the battery cell. Furthermore, the basic deformation corresponding to the temperature value detected by the temperature sensor in the sensor array can be used to perform temperature compensation on the deformation detected by the strain sensor in the sensor array and the pressure value detected by the pressure sensor in the sensor array. This eliminates or reduces the impact of temperature on deformation and pressure detection, allowing the compensated deformation and pressure values ​​to more accurately reflect the deformation and pressure conditions at the sensor array's location, thereby improving the accuracy and reliability of deformation and pressure detection in the battery cell assembly.

[0011] In some embodiments, the strain sensor is a strain grating inscribed in the optical fiber; the temperature sensor is a temperature grating inscribed in the optical fiber; and the pressure sensor is a pressure grating inscribed in the optical fiber.

[0012] The strain grating, the temperature grating and the pressure grating have different wavelength ranges.

[0013] In the battery cell assembly of this embodiment, a single grating can function as a sensor. By inscribing gratings corresponding to different wavelengths in the optical fiber, corresponding sensors can be obtained. This allows the demodulator to accurately demodulate the sensor signals of each sensor based on changes in the intensity, wavelength, frequency, phase, and polarization state of the received light, improving the reliability of obtaining the internal state of the battery cell.

[0014] In some embodiments, the grating is of a type of: Bragg grating, chirped grating, long period grating, blazed grating or phase grating.

[0015] In some embodiments, the temperature sensor is located between the strain sensor and the pressure sensor, thereby improving the reliability of temperature compensation.

[0016] In some embodiments, the optical fibers are arranged in a plurality; the plurality of optical fibers are evenly arranged inside the pole piece assembly.

[0017] The battery cell assembly of this embodiment can achieve uniform detection of the internal state of the electrode assembly, and can improve the accuracy of the detection of the internal state of the battery cell.

[0018] In some embodiments, the pole piece assembly is a wound structure including N turns, where N is an integer greater than 2;

[0019] The optical fibers are respectively arranged in the innermost circle, the middle circle and the outermost circle of the pole piece assembly.

[0020] The battery cell assembly of this embodiment can realize the coil-level status detection of the electrode assembly from the inside to the outside.

[0021] In some embodiments, the optical fiber is provided with a plurality of sensor arrays, and the plurality of sensor arrays are evenly arranged in the optical fiber.

[0022] The battery cell assembly of this embodiment can achieve uniform detection of the coil-level status and improve the reliability of the detection of the internal status of the battery cell.

[0023] In some embodiments, the pole piece assembly is a wound structure including N turns, where N is an integer greater than 2;

[0024] The optical fiber is arranged on a target circle, the target circle is composed of a plane and a curved surface, and the target circle is any circle among the N circles;

[0025] The sensor array is disposed in the optical fiber at positions corresponding to the following positions: a center position of the plane, a center position of the curved surface, and a center position of a connecting line between the plane and the curved surface.

[0026] The battery cell assembly of this embodiment can realize reliable monitoring of the coil-level status, thereby improving the reliability of the status detection of the electrode assembly.

[0027] In some embodiments, the optical fiber has a thickness of less than 10 microns.

[0028] The battery core assembly of this embodiment can reduce the impact of the optical fiber on the pole piece assembly.

[0029] In some embodiments, the optical fiber is fixed by packaging glue.

[0030] In a second aspect, an embodiment of the present application provides a battery cell, comprising:

[0031] Battery cell housing;

[0032] As described in the first aspect, the battery cell assembly is arranged in the battery cell shell.

[0033] In some embodiments, the optical fiber is further disposed outside the battery cell housing.

[0034] The battery cell of this embodiment can realize real-time detection of the internal state of the battery cell by disposing an optical fiber integrated with a sensor array inside the battery cell assembly, thereby improving the reliability of the battery cell state detection.

[0035] In some embodiments, the thickness of the optical fiber disposed outside the battery cell housing is less than 50 microns.

[0036] The battery cell of this embodiment can reduce the influence of the optical fiber on the battery cell.

[0037] In some embodiments, the battery cell further comprises:

[0038] a laser, the laser being disposed in the battery cell housing and electrically connected to the first end of the optical fiber;

[0039] A demodulator is arranged in the battery cell housing, the demodulator is electrically connected to the second end of the optical fiber, and the demodulator is used to demodulate the sensing signals of the sensors in the sensor array to obtain status information of the target position, where the target position is the setting position of the sensor array.

[0040] In the battery cell of this embodiment, the demodulator can accurately demodulate the sensing signals of each sensor based on changes in the intensity, wavelength, frequency, phase, polarization state, etc. of the received light, thereby improving the reliability of obtaining the internal state of the battery cell.

[0041] In some embodiments, when the sensor array includes strain sensors, temperature sensors, and pressure sensors, the demodulator is configured to:

[0042] Demodulating the sensing signal of the strain sensor to obtain a first deformation amount of the target position;

[0043] Demodulating the sensing signal of the temperature sensor to obtain a target temperature value of the target position;

[0044] The sensing signal of the pressure sensor is demodulated to obtain a first pressure value of the target position.

[0045] The battery cell assembly of this embodiment can realize real-time detection of the temperature, pressure and deformation inside the battery cell.

[0046] In a third aspect, an embodiment of the present application further provides a battery, comprising:

[0047] Battery housing;

[0048] As described in the second aspect, the battery cell is disposed in the battery housing.

[0049] The battery provided in the embodiment of the present application can realize real-time detection of the internal state of the battery cell because the optical fiber is provided inside the battery cell, thereby improving the reliability of the battery cell state detection.

[0050] In some embodiments, the optical fiber is further disposed outside the battery housing.

[0051] The battery of this embodiment can realize external status detection of battery cells and enrich the status detection methods.

[0052] In some embodiments, when the sensor array includes a strain sensor, a temperature sensor, and a pressure sensor, and the battery cell includes a demodulator, the battery further includes:

[0053] A battery management system is provided in the battery housing and is electrically connected to the demodulator. The battery management system is used to:

[0054] Subtracting a basic deformation value corresponding to the target temperature value from the first deformation value to obtain a second deformation value of the target position;

[0055] Subtracting a base pressure value corresponding to the target temperature value from the first pressure value to obtain a second pressure value at the target position;

[0056] The first deformation amount is the deformation amount of the target position detected by the strain sensor, and the first pressure value is the pressure value of the target position detected by the pressure sensor.

[0057] The battery of this embodiment can perform temperature compensation for deformation and pressure, thereby improving the reliability of deformation and pressure detection.

[0058] In some embodiments, when the battery cell includes a demodulator, the battery further includes:

[0059] A battery management system is provided in the battery housing and is electrically connected to the demodulator. The battery management system is used to:

[0060] comparing the target deformation variable output by the demodulator with a deformation variable threshold, and outputting deformation abnormality warning information when the target deformation variable is greater than the deformation variable threshold;

[0061] comparing the target pressure value output by the demodulator with a pressure threshold, and outputting pressure abnormality warning information when the target pressure value is greater than the pressure threshold;

[0062] The target deformation amount is the first deformation amount or the second deformation amount of the target position; and the target pressure value is the first pressure value or the second pressure value of the target position.

[0063] In this embodiment, when the target deformation value of a battery cell exceeds the deformation value threshold, a deformation anomaly warning message is output to warn that the cell deformation has exceeded the maximum deformation value. When the target pressure value exceeds the pressure value threshold, a deformation anomaly warning message is output to warn that the cell deformation has exceeded the maximum pressure value. If the cell continues to operate, it may cause a serious cell safety accident. This allows the user to stop the cell, thereby improving battery safety.

[0064] In some embodiments, when the optical fiber is further provided on the outside of the battery housing, the deformation abnormality warning information is used to indicate the cause of the abnormal deformation of the battery; the pressure abnormality warning information is used to indicate the cause of the abnormal pressure of the battery.

[0065] In this way, the user can know the cause of battery deformation or pressure.

[0066] In some embodiments, the battery management system is further configured to:

[0067] When the target position is located on the pole piece assembly, it is determined that the abnormal deformation of the battery is caused by abnormal deformation inside the battery cell assembly; when the target position is located outside the battery casing, it is determined that the abnormal deformation of the battery is caused by external force on the battery, and the target position is the setting position of the sensor array;

[0068] When the target position is located on the pole piece assembly, it is determined that the abnormal deformation of the battery is caused by abnormal internal pressure of the battery cell assembly; when the target position is located outside the battery shell, it is determined that the abnormal deformation of the battery is caused by external force.

[0069] In some embodiments, the battery further comprises:

[0070] A battery management system is provided in the battery housing and is electrically connected to the demodulator. The battery management system is used to:

[0071] Using the target location and the state information of the target location, training a state prediction model;

[0072] The state prediction model is used to predict state information of a second position, where the second position is located inside the pole piece assembly or outside the battery cell housing.

[0073] The battery cell of this embodiment can use the state prediction model to predict the state of each position, which can enrich the way of obtaining the battery state.

[0074] In a fourth aspect, an embodiment of the present application further provides an electrical device, including:

[0075] The battery according to the third aspect.

[0076] The electrical device provided in the embodiment of the present application can realize real-time detection of the internal state of the battery cell due to the sensor array integrated inside the battery cell, thereby improving the accuracy of the detection of the internal state of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. 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 the drawings without creative work.

[0078] Figure 1 A schematic top view of a battery cell assembly provided in an embodiment of the present application;

[0079] Figure 2 is a schematic structural diagram of a sensor array provided in an embodiment of the present application;

[0080] Figure 3 This is an external schematic diagram of a battery cell provided in an embodiment of the present application.

[0081] In the drawings, the drawings are not drawn to scale. DETAILED DESCRIPTION

[0082] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0083] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only 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 drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0084] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the 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.

[0085] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0086] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0087] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0088] The term "plurality" used in this application refers to two or more (including two).

[0089] In this application, battery cells may include lithium-ion secondary battery cells, lithium-ion primary battery cells, lithium-sulfur battery cells, sodium-lithium-ion battery cells, sodium-ion battery cells, or magnesium-ion battery cells, and the embodiments of this application are not limited thereto. Battery cells may be cylindrical, flat, rectangular, or in other shapes, and the embodiments of this application are not limited thereto.

[0090] In the embodiments of this application, Figure 1 As shown, the battery cell assembly includes a pole piece assembly 10 and an optical fiber 20 , and the optical fiber 20 is arranged on the pole piece assembly 10 .

[0091] Optical fiber 20 is provided with a sensor array 21. The sensors in the sensor array are all optical fiber sensors. Sensor array 21 can be used to detect status information of the location where sensor array 21 is set. The status information may include at least one of the following: temperature, deformation, pressure, etc.

[0092] The electrode assembly 10 may include a positive electrode sheet, a negative electrode sheet, and a separator separating the positive electrode sheet from the negative electrode sheet.

[0093] In some embodiments, as Figure 1 As shown, the electrode assembly 10 can be obtained by winding the positive electrode sheet, the negative electrode sheet and the separator. Figure 1 : is a top view schematic diagram of a battery cell assembly. In this embodiment, the pole piece assembly 10 is a wound structure, including N turns (also referred to as N layers, one turn is considered a layer), where N is an integer greater than 1, and the optical fiber can be arranged on the surface of the turns of the pole piece assembly 10, specifically, on the inner surface or outer surface of the turns of the pole piece assembly 10.

[0094] In other embodiments, the electrode assembly 10 may be formed by stacking a positive electrode, a negative electrode, and a separator. In this embodiment, the electrode assembly 10 is a laminated structure including N layers, where N is an integer greater than 1. The sensor array 21 may be disposed on a surface of a layer of the electrode assembly 10, specifically, on an inner or outer surface of a layer of the electrode assembly 10.

[0095] In an embodiment of the present application, by arranging an optical fiber with an integrated sensor array on the pole piece assembly, the state information inside the battery cell can be detected through the sensor array, thereby achieving real-time detection of the state inside the battery cell and improving the reliability of the detection of the internal state of the battery cell.

[0096] In some embodiments, the sensor array 21 may include at least one of the following: a strain sensor, a temperature sensor, and a pressure sensor.

[0097] The strain sensors in the sensor array 21 can be used to detect the deformation amount of the arrangement position of the sensor array 21 .

[0098] The temperature sensor in the sensor array 21 can be used to detect the temperature value of the location where the sensor array 21 is set.

[0099] The pressure sensor in the sensor array 21 can be used to detect the pressure value at the location where the sensor array 21 is set.

[0100] In this way, real-time detection of the temperature, pressure and deformation inside the battery cell can be achieved.

[0101] In some embodiments, the temperature sensor can also perform temperature compensation on the sensing signals detected by the strain sensor and the pressure sensor. In this embodiment, the temperature sensor can be located between the strain sensor and the pressure sensor, thereby improving the reliability of the temperature compensation.

[0102] In some embodiments, as Figure 2 As shown, the strain sensor is a strain grating 211 inscribed in the optical fiber 20; the temperature sensor is a temperature grating 212 inscribed in the optical fiber 20; and the pressure sensor is a pressure grating 213 inscribed in the optical fiber 20;

[0103] The strain grating 211 , the temperature grating 212 , and the pressure grating 213 have different wavelength ranges.

[0104] In this embodiment, a grating can serve as a sensor. By inscribing gratings corresponding to different wavelength ranges in the optical fiber 20, corresponding sensors can be obtained. In this way, the demodulator can accurately demodulate the sensing signals of each sensor based on changes in the intensity, wavelength, frequency, phase, and polarization state of the received light, thereby improving the reliability of obtaining the internal state of the battery cell.

[0105] In the embodiments of the present application, the grating type may be a Bragg grating, a chirped grating, a long-period grating, a blazed grating, or a phase grating. It is understood that the grating type may be the same or different for different gratings, depending on actual needs and is not limited in the embodiments of the present application.

[0106] In some embodiments, the number of optical fibers provided may be one. In this embodiment, for a wound pole piece assembly 10, the optical fiber may be provided at the innermost coil of the pole piece assembly 10; for a laminated pole piece assembly 10, the optical fiber may be provided in the middle layer of the pole piece assembly 10. This allows for instant detection of the internal state of the battery cell for deformation from the inside out.

[0107] In other embodiments, the number of optical fibers can be multiple. In this embodiment, multiple optical fibers can be evenly arranged on the pole piece assembly 10, so that the internal state of the pole piece assembly 10 can be evenly detected, which can improve the accuracy of the internal state detection of the battery cell.

[0108] In some optional implementations, for the pole piece assembly 10 of the winding structure, such as Figure 1 As shown, the optical fibers can be respectively arranged in the innermost circle 11, the middle circle 12 and the outermost circle 13 of the pole piece assembly 10.

[0109] In this way, the coil-level state detection of the pole piece assembly 10 from the inside to the outside can be achieved. Furthermore, the cause of the deformation (or the cause of the pressure) can be analyzed by comparing the deformation variables (or pressure values) detected by the optical fibers set in each coil. For example, if the deformation variable (or pressure value) detected by the optical fibers set in the outer coil is greater than the deformation variable (or pressure value) detected by the optical fibers set in the inner coil, it means that the deformation (or pressure) is generated from the outside to the inside, and the cause of the deformation (or pressure) may be external, such as deformation (or pressure) caused by external force compression; if the deformation variable (or pressure value) detected by the optical fibers set in the inner coil is greater than the deformation variable (or pressure value) detected by the optical fibers set in the inner coil, it means that the deformation (or pressure) is generated from the inside to the outside, and the cause of the deformation (or pressure) may be internal, such as deformation caused by gas generation or expansion of the battery cell. In this way, the reliability of the state detection can be further improved.

[0110] Furthermore, the optical fiber 20 may include multiple sensor arrays 21, each evenly distributed throughout the optical fiber 20. For example, the sensor arrays 21 may be located at representative locations within the optical fiber 20, such as the center and inflection points of each winding structure. This allows for uniform detection of each winding structure, improving the reliability of detecting the internal state of the battery cell.

[0111] In an optional implementation, the optical fiber is arranged on a target circle, the target circle is composed of a plane and a curved surface, and the target circle is any circle among N circles;

[0112] The sensor array 21 is disposed in the optical fiber 20 at positions corresponding to the following positions: the center position of the plane, the center position of the curved surface, and the center position of the connecting line between the plane and the curved surface.

[0113] The pole piece assembly 10 is comprised of a flat surface and a curved surface. Specifically, it comprises two flat surfaces and two curved surfaces. In some embodiments, the flat surface may be referred to as a large surface, and the curved surface may be referred to as a corner. The edge of the corner is the connecting line between the flat surface and the curved surface. In an optional implementation, a sensor array 21 may be provided on the large surface and the corner.

[0114] As an example, Figure 1 As shown, a sensor array 21 can be set at the center of the plane, a sensor array 21 can be set at the center of the curved surface, and a sensor array 21 can be set at the center of the connecting line between the curved surface and the plane. In this way, reliable monitoring of the coil-level status can be achieved, thereby improving the reliability of the status detection of the pole piece assembly 10.

[0115] For the pole piece assembly 10 of the laminated structure, similarly, multiple sensor arrays 21 can be respectively arranged at the bottom layer, the middle layer and the top layer of the pole piece assembly 10. In this way, the layer status detection of the pole piece assembly 10 from the inside to the outside can be achieved.

[0116] In some embodiments, the thickness of the optical fiber is less than 10 microns. Further, the thickness of the optical fiber can be less than 5 microns. In this way, the impact of the optical fiber on the pole piece assembly 10 can be reduced.

[0117] The embodiments of the present application do not limit the method for fixing the optical fiber. In some embodiments, the optical fiber is fixed by packaging glue.

[0118] The embodiment of the present application further provides a battery cell, comprising a battery cell housing 30 and a battery cell assembly provided in the embodiment of the present application, wherein the battery cell assembly is disposed in the battery cell housing 30 .

[0119] The battery cell of the embodiment of the present application can realize real-time detection of the internal state of the battery cell by disposing an optical fiber integrated with a sensor array inside the battery cell assembly, thereby improving the reliability of the battery cell state detection.

[0120] In some embodiments, an optical fiber may be provided on the outside of the cell housing to detect cell deformation and pressure caused by external forces such as squeezing, collision, or scraping, thus enabling status detection from the inside out and from the outside in.

[0121] The number of optical fibers installed on the outside of the cell shell can be one or more, and the selection of the installation position is representative and can fully reflect the state of the outside of the cell. In some optional implementations, the sensor array 21 can be installed on the large surface, side surface, bottom surface and four corners of the cell shell. For easy understanding, please refer to Figure 3 .

[0122] In some embodiments, the thickness of the optical fiber disposed outside the battery cell housing may be less than 50 microns, thereby reducing the impact of the optical fiber on the battery cell.

[0123] In some embodiments, the battery cell further comprises:

[0124] A laser is disposed in the battery cell housing and is electrically connected to the first end of the optical fiber;

[0125] The demodulator is arranged in the battery cell shell and is electrically connected to the second end of the optical fiber. The demodulator is used to demodulate the sensing signals of the sensors in the sensor array 21 to obtain the status information of the target position, which is the setting position of the sensor array 21.

[0126] The laser and demodulator are located outside the battery cell assembly. The laser is used to emit laser light toward the first end of the optical fiber 20, and the demodulator is used to extract the optical signal from the second end of the optical fiber 20. Therefore, the first end of the optical fiber 20 can be considered the input light port, and the second end of the optical fiber 20 can be considered the output light port.

[0127] In this way, the demodulator can accurately demodulate the sensing signals of each sensor based on changes in the intensity, wavelength, frequency, phase, polarization state, etc. of the received light, thereby improving the reliability of obtaining the internal state of the battery cell.

[0128] In some embodiments, when the sensor array 21 includes strain sensors, temperature sensors, and pressure sensors, the demodulator can be specifically used to:

[0129] Demodulating the sensing signal of the strain sensor to obtain a first deformation amount of the target position;

[0130] Demodulate the sensing signal of the temperature sensor to obtain the target temperature value at the target position;

[0131] The sensing signal of the pressure sensor is demodulated to obtain a first pressure value at the target position.

[0132] In this way, deformation, temperature and pressure detection can be achieved.

[0133] An embodiment of the present application further provides a battery, comprising: a battery housing and a battery cell provided in an embodiment of the present application, wherein the battery cell is disposed in the battery housing.

[0134] In practical applications, a battery may include one or more battery cells.

[0135] The battery may be a battery module or a battery pack. In the case of a battery module, the battery module may include at least one battery cell. In the case of a battery pack, the battery pack may include at least one battery module.

[0136] Since the optical fiber is provided inside the battery cell, the internal state of the battery cell can be detected immediately, thereby improving the reliability of the battery cell state detection.

[0137] In some embodiments, an optical fiber is further provided on the outside of the battery housing, thereby enabling external status detection of the battery cell and enriching the methods of status detection.

[0138] In some embodiments, when the sensor array 21 includes strain sensors, temperature sensors, and pressure sensors, and the battery cell includes a demodulator, the battery may further include: a battery management system (BMS), which is disposed in the battery housing and is electrically connected to the demodulator.

[0139] Battery management systems can be used for:

[0140] Subtract the basic deformation corresponding to the target temperature value from the first deformation to obtain the second deformation at the target position;

[0141] Subtract the base pressure value corresponding to the target temperature value from the first pressure value to obtain a second pressure value at the target position;

[0142] The first deformation amount is the deformation amount of the target position detected by the strain sensor, and the first pressure value is the pressure value of the target position detected by the pressure sensor.

[0143] In this embodiment, the BMS can use the basic deformation variable corresponding to the temperature value detected by the temperature sensor in the sensor array 21 to perform temperature compensation on the deformation variable detected by the strain sensor in the sensor array 21 and the pressure value detected by the pressure sensor in the sensor array 21. The first deformation variable is the deformation variable before temperature compensation, the second deformation variable is the deformation variable after temperature compensation, the first pressure value is the pressure value before temperature compensation, and the second pressure value is the pressure value after temperature compensation. In this way, the influence of temperature on deformation and pressure detection is eliminated or reduced, so that the compensated deformation variable and pressure value more accurately reflect the deformation and pressure conditions of the setting position of the sensor array 21, thereby improving the accuracy and reliability of deformation detection and pressure detection of battery cell components.

[0144] The basic deformation variable (or basic pressure value) corresponding to the temperature value can reflect the influence of temperature on deformation (or pressure) detection. The basic deformation variable (or basic pressure value) corresponding to the temperature value can be tested. During the testing phase, the temperature of the battery cell assembly can be changed by changing the environment in which the battery cell assembly is located, thereby making the temperature value detected by the temperature sensor in the sensor array 21 in the battery cell assembly different. The deformation variable (or pressure value) detected by the strain sensor (or pressure sensor) in the sensor array 21 in each environment is used as the basic deformation variable (or basic pressure value) corresponding to the temperature value detected by the temperature sensor in the sensor array 21, and the basic deformation variable (or basic pressure value) corresponding to different temperature values ​​is obtained.

[0145] It is understandable that the degree of influence of temperature on deformation (or pressure) may be different at different positions in the electrode assembly. Therefore, for sensor arrays 21 at different positions, the basic deformation value (or basic pressure value) corresponding to the same temperature value may be different, which is determined based on actual test results.

[0146] In some embodiments, the battery management system is further configured to:

[0147] Compare the target deformation variable output by the demodulator with the deformation variable threshold, and output deformation abnormality warning information when the target deformation variable is greater than the deformation variable threshold;

[0148] Compare the target pressure value output by the demodulator with the pressure threshold, and output a pressure abnormality warning message when the target pressure value is greater than the pressure threshold;

[0149] The target deformation value is the first deformation value or the second deformation value of the target position; and the target pressure value is the first pressure value or the second pressure value of the target position.

[0150] The deformation threshold may be: the maximum deformation allowed for the battery cell under normal operation. The pressure threshold may be: the maximum pressure allowed for the battery cell under normal operation.

[0151] When the target deformation variable is greater than the deformation variable threshold, a deformation abnormality warning message is output to warn that the battery cell deformation has exceeded the maximum deformation variable. If the battery cell continues to work, it may cause a serious battery cell safety accident, so that the user can operate the battery cell to stop working, thereby improving the safety of battery use.

[0152] When the target pressure value is greater than the pressure value threshold, an abnormal deformation warning message is output to warn that the battery cell deformation has exceeded the maximum pressure value. If the battery cell continues to work, it may cause a serious battery cell safety accident, so that the user can operate the battery cell to stop working, thereby improving the safety of battery use.

[0153] Furthermore, when an optical fiber is further provided on the outside of the battery housing, the deformation abnormality warning information is used to indicate the cause of the abnormal deformation of the battery cell; the pressure abnormality warning information is used to indicate the cause of the abnormal pressure of the battery cell.

[0154] In some embodiments, the battery management system may also be used to:

[0155] When the target position is located on the pole piece assembly 10, it is determined that the abnormal deformation of the battery is caused by abnormal deformation inside the battery cell assembly; when the target position is located outside the battery casing, it is determined that the abnormal deformation of the battery is caused by external force;

[0156] When the target position is on the pole piece assembly 10, it is determined that the abnormal deformation of the battery cell is caused by abnormal internal pressure of the battery cell assembly; when the target position is outside the battery shell, it is determined that the abnormal deformation of the battery is caused by external force.

[0157] As can be seen from the above content, optical fibers can be set both inside and outside the battery cell assembly. The optical fibers set inside the battery cell assembly are used to detect the internal state of the battery cell assembly, and the optical fibers set outside the battery cell assembly are used to detect the external state of the battery cell assembly.

[0158] The demodulator and the battery management system can distinguish the optical fibers corresponding to the various state quantities (or pressure values) after demodulation.

[0159] If the target state quantities (or target pressure values) greater than the state quantity threshold are all optical fibers arranged inside the battery cell assembly, it can be determined that the deformation (or pressure) occurs inside the battery cell assembly, and the cause of the deformation (or pressure) is the deformation (or pressure generation) inside the battery cell assembly.

[0160] If the target state quantities (or target pressure values) greater than the state quantity threshold are all optical fibers arranged outside the battery cell assembly, it can be determined that the deformation (or pressure) occurs outside the battery cell assembly, and the cause of the deformation (or pressure) is the deformation (or pressure) of the outside of the battery cell assembly.

[0161] If the target state quantity (or target pressure value) greater than the state quantity threshold corresponds to an optical fiber arranged outside the battery cell assembly and an optical fiber arranged inside the battery cell assembly, the battery management system can determine the cause of deformation (or pressure cause) by first detecting the setting position of the optical fiber corresponding to the target state quantity (or target pressure value) greater than the state quantity threshold.

[0162] The setting position of the optical fiber corresponding to the target state quantity (or target pressure value) that is previously detected to be greater than the state quantity threshold is the optical fiber set outside the battery cell assembly, indicating that the deformation (or pressure) inside the battery cell assembly is caused by external deformation (or pressure), and the state cause is the external deformation of the battery cell assembly (or pressure).

[0163] The setting position of the optical fiber corresponding to the target state quantity (or target pressure value) that is previously detected to be greater than the state quantity threshold is the optical fiber set inside the battery cell assembly, indicating that the deformation (or pressure) outside the battery cell assembly is caused by the internal deformation (or pressure), and the state cause is the internal deformation of the battery cell assembly (or the generation of pressure).

[0164] In this way, the causes of deformation and stress generation can be accurately identified.

[0165] In some embodiments, the battery management system may also be used to:

[0166] The target position and the state information of the target position are used to train the state prediction model. The target position is the location where the optical fiber is installed;

[0167] The state prediction model is used to predict the state information of the second position, where the second position is located inside the pole piece assembly 10 or outside the battery cell housing.

[0168] In this embodiment, a state prediction model can be established, and the state information detected by the optical fiber can be used to train the state prediction model and calibrate the state prediction model. Thereafter, the state prediction model can be used to predict the state of each location.

[0169] In specific implementation, a state prediction model can be established for the inside and outside of the battery cell respectively.

[0170] For the state prediction model inside the battery cell, the state information detected by the optical fiber arranged inside the battery cell can be used to train the state prediction model, and then the state prediction model is used to predict the state information of each position inside the battery cell.

[0171] For the state prediction model outside the battery cell, the state information detected by the optical fiber arranged outside the battery cell can be used to train the state prediction model, and then the state prediction model is used to predict the state information of each position outside the battery cell.

[0172] In this way, the status of each battery position can be predicted, and the method of obtaining the battery status can be enriched.

[0173] An embodiment of the present application also provides an electrical device, including the battery provided in the embodiment of the present application.

[0174] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0175] In the embodiments of this application:

[0176] 1) Optical fibers are arranged inside the battery cell electrodes, and distributed pressure, strain, and temperature sensor arrays are integrated inside the optical fibers. These sensors are distributed on the battery cell electrodes to collect pressure, temperature, and deformation signals at the electrode level, thereby determining the stress, temperature, and deformation degree inside the battery cell. The multi-parameter and multi-position display of the electrode status inside the battery cell is more accurate and rapid.

[0177] A fiber-optic distributed sensor array integrates temperature, pressure, and strain sensors, all of which are fiber-optic sensors. By inscribing numerous gratings into a long optical fiber, each grating functions as a single strain sensor. Fiber optics are then placed within the electrode, such as on the outermost, middle, and innermost surfaces and corners, to measure changes in pressure, temperature, and strain distribution from the inside out.

[0178] Distributed deformation sensors built into the pole piece layer directly measure the degree of deformation pressure within the battery cell, more accurately determining the pressure and strain within the cell. This allows for faster detection and early warning of cells exhibiting abnormal deformation pressure, enabling non-destructive testing without disassembling the cell. Sensors with varying numbers of turns are distributed throughout the winding structure, covering both large surfaces and corners, forming a three-dimensional monitoring and sensing network. This provides real-time feedback on measurement results, enabling the construction of a three-dimensional simulation model of cell force and heat, enabling prediction of force and heat at every location within the cell.

[0179] 2) The temperature sensor can not only reflect the temperature conditions inside the battery cell, but also perform temperature compensation on the deformation and pressure signals measured by the integrated deformation and pressure sensors, thereby eliminating the interference of temperature changes on deformation testing.

[0180] Temperature is a significant factor influencing fiber optic test signals. Temperature fluctuations cannot be completely eliminated in a battery system, meaning that both the inside and outside of the battery cannot maintain a constant temperature. This is primarily due to factors such as resistance and heat release during the charge and discharge process. By integrating temperature sensors with deformation and pressure sensors to form a sensor array, the surrounding temperature can be measured simultaneously with deformation and pressure. This allows for temperature compensation of deformation and pressure signals, eliminating the impact of temperature on deformation and pressure tests and enabling deformation and pressure tests to more accurately reflect the deformation of the battery cell and electrode itself.

[0181] 3) In addition to the internal arrangement of temperature, pressure, and deformation sensor arrays, sensors are arranged on the outside of the cell shell, module, and battery pack, such as the large surface, four corners, and sides, to further determine the deformation, pressure, and temperature status of the cell. This can reflect abnormal conditions such as stress and deformation caused by external extrusion, collision, and scraping of the battery pack, module, or cell.

[0182] When cells, modules, and battery packs are deformed by external forces such as squeezing, collision, or scraping, the deformation is further transmitted to the interior of the cells. At this time, the signal is transmitted from the outside to the inside. Sensors are placed on the exterior of the cell housing, modules, and battery packs, such as the large surfaces, corners, and sides, to further determine the deformation state of the cells. Combined with internal sensing technology, deformation pressure detection can be achieved from the inside out and from the outside in.

[0183] In some embodiments:

[0184] Step 1: Implant deformation, pressure, and temperature sensors into the electrode.

[0185] The deformation, temperature and pressure are combined into a sensing unit. Each sensing unit works as a single strain sensor array. Multiple sensing units are distributed in one optical fiber, and one optical fiber is distributed in the battery cell electrode. The arrangement is as follows: Figure 1 shown.

[0186] At the pole piece level, optical fibers with concentrated sensing units are distributed on the pole piece surface, with sensing units arranged at the four corners, the middle of the edge, and the center of the pole piece for monitoring. In the thickness direction of the battery cell, optical fibers are arranged on the outermost, middle, and innermost pole pieces of the winding structure to measure the temperature, pressure, and deformation of different windings, determine the signal changes from the outside to the inside of the battery cell winding structure, and form a three-dimensional sensing monitoring network. An interactive coupling simulation model of the force field and thermal field at the pole piece level is established to predict the thermal, force, and deformation parameters of a single pole piece or pole pieces with different layers at any position. The model is calibrated using measured data to further optimize the model prediction accuracy.

[0187] by Figure 1 Taking the winding structure of the pole piece assembly as an example, the following description is made:

[0188] The positive electrode, separator and negative electrode of the battery cell are wound, and optical fibers are arranged in the outermost layer, middle layer and innermost layer of the wound structure.

[0189] Several sensor arrays are integrated into one optical fiber. Each sensor array unit includes temperature, pressure and deformation grating parts. After a single sensor array is amplified, Figure 2 As shown, the integrated optical fiber is mainly composed of three gratings in different wavelength ranges, among which the temperature grating is in the middle, which can perform temperature compensation with the pressure and deformation measurement grating next to it.

[0190] The grating types can be: Bragg grating, chirp grating, long period grating, blazed grating, phase grating, etc.

[0191] Each layer is a separate optical fiber. Light enters the fiber and exits at the end. The exiting light is then demodulated by a demodulator, displaying the temperature, pressure, and deformation corresponding to each area. The optical fiber inside the electrode is secured to the electrode surface with encapsulation adhesive. The diameter of the encapsulated optical fiber should be less than 10 μm to avoid affecting the interface of the battery cell.

[0192] Step 2: Arrange deformation and temperature sensors on the outside of the battery cell, module, and battery pack.

[0193] At the cell housing, module, and battery pack levels, optical fibers containing concentrated sensor units are distributed across the cell housing, module, and battery pack surfaces, with sensor units placed at the four corners, edges, and center to collect sensor signals. This creates a three-level sensor network for the cell housing, module, and battery pack. This network monitors external mechanical abuse, such as scraping, squeezing, and vibration, for the battery pack, module, and cell housing. This allows for real-time monitoring of external forces, heat, and deformation, and establishes an interactively coupled simulation model for force and thermal fields. This allows for prediction of thermal and force parameters at any external location, and allows for model calibration using measured data to further optimize model prediction accuracy.

[0194] by Figure 2 For example, the following description is given:

[0195] The optical fiber with the integrated sensor array is fixed to the battery cell, module, and battery pack using encapsulant on the large surfaces and sides. The optical fiber is located at the four corners, the center, and the middle of the edge line of the battery cell, module, and battery pack. There are two separate optical fibers on the large surface and one on the side. The optical fiber has incident light and outgoing light at the end. The outgoing light is then sent to the demodulator for demodulation, indicating the temperature, pressure, and deformation conditions corresponding to each area. The optical fiber on the outside of the battery cell can be fixed tightly to the battery cell with encapsulant. The surface of the module and battery pack, including the encapsulated optical fiber, should have a diameter of less than 50μm to avoid affecting the battery cell layout.

[0196] Step 3: Measure the effect of temperature on strain detection and perform temperature compensation.

[0197] For cells, modules, and battery packs equipped with internal and external temperature, deformation, pressure, and temperature sensors, the corresponding deformation variables X0 and pressure P0 at different locations and temperatures T are measured under varying environmental conditions. These values ​​are used as the baseline deformation and pressure X0 and P0 at that temperature T. Subsequent deformation tests should subtract these baseline deformation and pressure X0 and P0 to eliminate the effects of temperature fluctuations on strain and pressure.

[0198] Step 4: Measure the deformation, pressure and temperature data of each position under the actual state.

[0199] Take the temperature T, deformation and pressure X1 and P1 corresponding to different positions of the battery cells, modules and battery packs where the internal and external temperature deformation sensors are arranged. The basic deformation and pressure X0 at the position are determined according to the temperature. After eliminating the influence of temperature fluctuations on strain and pressure, the real deformation X=X1-X0 and P=P1-P0.

[0200] Step 5: Detection, early warning and judgment of deformation.

[0201] When the actual deformation value X at any location on a cell, module, or battery pack is compared with the deformation warning value X*, a deformation warning is issued for that location if X>X*. If the deformation warning first appears in the module or battery pack, an external force abnormality warning is issued. If the deformation warning first appears inside the cell, an internal deformation abnormality warning is issued.

[0202] Step 6: Detection, early warning and judgment of local overvoltage.

[0203] When the actual pressure P at any location on a cell, module, or battery pack is compared with the pressure warning value P*, a pressure warning is issued for that location if P>P*. If the pressure warning first appears in the module or battery pack, a warning of an external force anomaly is issued. If the pressure warning first appears inside the cell, a warning of an internal pressure anomaly is issued.

[0204] 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 of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery cell assembly comprising: Pole piece assembly; An optical fiber is provided on the pole piece assembly, and the optical fiber is provided with a sensor array, and the sensors in the sensor array are all optical fiber sensors.

2. The battery cell assembly according to claim 1, wherein: The sensor array includes at least one of the following: a strain sensor, a temperature sensor, and a pressure sensor.

3. The battery cell assembly according to claim 2, wherein: The strain sensor is a strain grating inscribed in the optical fiber; the temperature sensor is a temperature grating inscribed in the optical fiber; and the pressure sensor is a pressure grating inscribed in the optical fiber. The strain grating, the temperature grating and the pressure grating have different wavelength ranges.

4. The battery cell assembly according to claim 3, wherein: The type of the grating is: Bragg grating, chirp grating, long period grating, blazed grating or phase grating.

5. The battery cell assembly according to claim 2, wherein: The temperature sensor is located between the strain sensor and the pressure sensor.

6. The battery cell assembly according to claim 1, wherein: There are multiple optical fibers arranged; the multiple optical fibers are evenly arranged on the pole piece assembly.

7. The battery cell assembly according to claim 6, wherein: The pole piece assembly is a wound structure, comprising N turns, where N is an integer greater than 2; The optical fibers are respectively arranged in the innermost circle, the middle circle and the outermost circle of the pole piece assembly.

8. The battery cell assembly according to claim 1, wherein: The optical fiber is provided with a plurality of sensor arrays, and the plurality of sensor arrays are evenly arranged in the optical fiber.

9. The battery cell assembly according to claim 8, wherein: The pole piece assembly is a wound structure, comprising N turns, where N is an integer greater than 2; The optical fiber is arranged on a target circle, the target circle is composed of a plane and a curved surface, and the target circle is any circle among the N circles; The sensor array is disposed in the optical fiber at positions corresponding to the following positions: a center position of the plane, a center position of the curved surface, and a center position of a connecting line between the plane and the curved surface.

10. The battery cell assembly according to claim 1, wherein: The thickness of the optical fiber is less than 10 microns.

11. The battery cell assembly according to claim 1, wherein: The optical fiber is fixed by packaging glue.

12. A battery cell comprising: Battery cell housing; The battery cell assembly according to any one of claims 1 to 11, wherein the battery cell assembly is arranged in the battery cell shell.

13. The battery cell according to claim 12, wherein: The optical fiber is also arranged outside the battery cell shell.

14. The battery cell according to claim 13, wherein: The thickness of the optical fiber disposed outside the battery cell housing is less than 50 microns.

15. The battery cell according to claim 12, wherein: The battery cell further comprises: a laser, the laser being disposed in the battery cell housing and electrically connected to the first end of the optical fiber; A demodulator is arranged in the battery cell housing, the demodulator is electrically connected to the second end of the optical fiber, and the demodulator is used to demodulate the sensing signals of the sensors in the sensor array to obtain status information of the target position, where the target position is the setting position of the sensor array.

16. The battery cell according to claim 15, wherein: In the case where the sensor array includes strain sensors, temperature sensors, and pressure sensors, the demodulator is used to: Demodulating the sensing signal of the strain sensor to obtain a first deformation amount of the target position; Demodulating the sensing signal of the temperature sensor to obtain a target temperature value of the target position; The sensing signal of the pressure sensor is demodulated to obtain a first pressure value of the target position.

17. A battery comprising: Battery housing; The battery cell according to any one of claims 12 to 16, wherein the battery cell is disposed in the battery housing.

18. The battery according to claim 17, wherein The optical fiber is also arranged outside the battery housing.

19. The battery according to claim 17, wherein In the case where the sensor array includes a strain sensor, a temperature sensor, and a pressure sensor, and the battery cell includes a demodulator, the battery further includes: A battery management system is provided in the battery housing and is electrically connected to the demodulator. The battery management system is used to: Subtracting a basic deformation value corresponding to the target temperature value from the first deformation value to obtain a second deformation value of the target position; Subtracting a base pressure value corresponding to the target temperature value from the first pressure value to obtain a second pressure value at the target position; Wherein, the first deformation amount is the deformation amount of the target position detected by the strain sensor, and the first pressure value is the pressure value of the target position detected by the pressure sensor.

20. The battery according to claim 17, wherein In the case where the battery cell includes a demodulator, the battery further includes: A battery management system is provided in the battery housing and is electrically connected to the demodulator. The battery management system is used to: comparing the target deformation variable output by the demodulator with a deformation variable threshold, and outputting deformation abnormality warning information when the target deformation variable is greater than the deformation variable threshold; comparing the target pressure value output by the demodulator with a pressure threshold, and outputting pressure abnormality warning information when the target pressure value is greater than the pressure threshold; The target deformation amount is the first deformation amount or the second deformation amount of the target position, and the target position is the setting position of the sensor array; the target pressure value is the first pressure value or the second pressure value of the target position.

21. The battery according to claim 20, wherein In the case where the optical fiber is further provided on the outside of the battery housing, the deformation abnormality warning information is used to indicate the cause of the abnormal deformation of the battery; the pressure abnormality warning information is used to indicate the cause of the abnormal pressure of the battery.

22. The battery according to claim 20, wherein The battery management system is also used for: When the target position is located on the pole piece assembly, it is determined that the abnormal deformation of the battery is caused by abnormal deformation inside the battery cell assembly; when the target position is located outside the battery casing, it is determined that the abnormal deformation of the battery is caused by external force on the battery; When the target position is located on the pole piece assembly, it is determined that the abnormal deformation of the battery is caused by abnormal internal pressure of the battery cell assembly; when the target position is located outside the battery shell, it is determined that the abnormal deformation of the battery is caused by external force.

23. The battery according to claim 18, wherein In the case where the battery cell includes a demodulator, the battery further includes: A battery management system is provided in the battery housing and is electrically connected to the demodulator. The battery management system is used to: Training a state prediction model using a target position and state information of the target position, wherein the target position is a setting position of the sensor array; The state prediction model is used to predict state information of a second position, where the second position is located inside the pole piece assembly or outside the battery housing.

24. An electrical device comprising: A battery as claimed in any one of claims 17 to 23.

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