Battery cell, battery, and power consumption device

Abstract

A battery cell (7), a battery (2), and an electric power consumption device. The battery cell (7) includes a housing (20), an electrode assembly (11), and an optical fiber (8). The electrode assembly (11) is housed within the housing (20). The optical fiber (8) includes a first segment (81) and a second segment (82). The first segment (81) is bonded to the electrode assembly (11), and the second segment (82) is connected to the first segment (81) and extends outside the housing (20). The axes of the first segment (81) and the second segment (82) are alternately arranged. The optical fiber (8) is used to acquire the state signal of the battery cell (7). The embodiment realizes simultaneously monitoring the temperature change and strain of the battery cell, and can improve the operation safety and stability of the battery cell (7).

Description

Cross - reference to related applications

[0001] This application claims the priority of Chinese Patent Application No. 202211531135.1, titled "Battery Cell, Battery and Power - consuming Device", filed on December 01, 2022, and the entire content of the same application is incorporated herein by reference.

Technical Field

[0002] This application relates to the field of batteries, and particularly to battery cells, batteries and power - consuming devices.

Background Art

[0003] Battery cells are widely applied to electronic devices, such as mobile communication devices, notebook computers, electric bicycles, electric vehicles, electric airplanes, electric ships, electric toys and electric tools. The battery cells may include nickel - chromium battery cells, nickel - hydrogen battery cells, lithium - ion battery cells and secondary alkaline zinc - manganese battery cells, etc.

[0004] Currently, how to improve the safety performance of battery cells and how to timely monitor and control the operating conditions of battery cells are one of the research focuses in this field.

Summary of the Invention

[0005] In view of the above problems, this application provides a battery cell, a battery and a power - consuming device that can monitor and control the operating conditions of the battery cell and improve the safety and stability of the operation of the battery cell.

[0006] According to a first aspect, the present application provides a battery cell, which includes a housing, an electrode assembly, and an optical fiber. The electrode assembly is housed within the housing. The optical fiber includes a first segment and a second segment. The first segment is bonded to the electrode assembly. The second segment is connected to the first segment and extends outside the housing. The axes of the first segment and the second segment are alternately arranged. The optical fiber is used to acquire the state signal of the battery cell.

[0007] In the technical solution of the embodiment of the present application, the optical fiber includes a first segment and a second segment that are connected to each other. The first segment is bonded to the electrode assembly, which can improve the detection sensitivity of the optical fiber to the temperature or strain of the electrode assembly and improve the accuracy and efficiency of the state monitoring of the battery cell. The second segment extends outside the housing and is used to transmit the internal state information of the electrode assembly to the outside. The axes of the first segment and the second segment are alternately arranged, and the second segment does not contact the electrode assembly. Due to the photo-thermal effect, it causes changes in the central wavelength of the Bragg mode and the central wavelength of the Ghost mode of the single-mode optical fiber. The above changes can reflect the thickness change and surface temperature change of the electrode assembly. Therefore, the above structure can realize the simultaneous monitoring of the temperature change and strain of the battery cell and improve the operation safety and stability of the battery cell.

[0008] In some embodiments, the state signal includes a Ghost signal and a Bragg signal. The Ghost signal is used to acquire the strain information of the battery cell, and the Bragg signal is used to acquire the temperature information of the battery cell. By acquiring the change situation of the Ghost signal and the Bragg signal in the single-mode optical fiber, the above signals have high test sensitivity and fast speed for the strain and temperature changes of the battery cell, and can effectively monitor the changes in the state information of the battery cell.

[0009] In some embodiments, the diameter of the first segment is not equal to the diameter of the second segment, or the diameter of the first segment is equal to the diameter of the second segment. In the above technical solution, the equal diameters of the first segment and the second segment can facilitate the manufacture and assembly of the optical fiber. The unequal diameters of the first segment and the second segment can facilitate the connection of one second segment to a plurality of first segments simultaneously, and at the same time, a plurality of monitoring points of the battery cell can be monitored.

[0010] In some embodiments, the length of the second segment is L1, where 1 mm ≤ L1 ≤ 2 cm. The second segment is used to connect the first segment and external signaling devices. By setting a reasonable length of the second segment, it can be ensured that the information collected in the first segment is transmitted, and at the same time, the space occupied by the second segment is reduced.

[0011] In some embodiments, the first segment and the second segment are connected by welding. The welding connection method can ensure the stability of signal transmission in the optical fiber and the strength of the connection between the first segment and the second segment. At the same time, the melting operation is simple and the connection efficiency is high.

[0012] In some embodiments, the optical fiber further includes a third segment. The third segment is connected to one end of the first segment away from the second segment, and a Bragg grating is provided on the third segment. By installing a Bragg grating on the optical fiber, spectral information including Bragg mode and Ghost mode can be obtained. The change in the Ghost mode intensity of the Bragg grating spectrum exhibits a certain response relationship with strain, and the drift of the Bragg wavelength in the Bragg grating spectrum exhibits a certain response relationship with temperature. The spectrum demodulator simultaneously analyzes the spectra of these two modes, thereby simultaneously obtaining the strain and temperature change information of the battery cell to be measured.

[0013] In some embodiments, the third segment and the second segment are integrally formed. The above structure can improve the manufacturing efficiency of the third segment.

[0014] In some embodiments, the length of the third segment is L2, where 1 mm ≤ L2 ≤ 5 cm. By setting a reasonable length of the third segment, the accuracy of the spectral signal can be guaranteed, and at the same time, the occupied space of the third segment can be made as small as possible.

[0015] In some embodiments, the electrode assembly includes electrode plates and separators that are stacked, and at least a part of the third segment is provided between the electrode plate and the separator of the battery cell, or at least a part of the third segment is provided between two separators of the battery cell. The optical fiber is installed at the above position, and the local temperature and thickness change conditions during the operation process of the battery cell can be obtained more accurately, further improving the monitoring efficiency and accuracy of the battery cell.

[0016] In some embodiments, the number of the second segments is plural, and the plural second segments are connected to at least one first segment, and each second segment is connected to at least one electrode assembly respectively. Each second segment can obtain information of at least one monitoring point, and the plural second segments can obtain plural monitoring information simultaneously. The above structure can install plural monitoring points on the same battery cell, or install monitoring points on plural battery cells respectively. The same first segment can be connected to plural second segments. The above structure can increase the monitoring points of the battery cell, simplify the structure of the first segment, guarantee the transmission of the spectral signal, simplify the optical fiber structure, and improve the efficiency of information transmission.

[0017] According to a second aspect, an embodiment of the present application provides a method for monitoring a battery cell to monitor state information of the battery cell. The monitoring method includes obtaining initial state information of the battery cell, including an initial Ghost mode signal and an initial Bragg mode signal, based on an initial probe signal of an optical fiber; obtaining first state information of the battery cell, including a first Ghost mode signal and a first Bragg mode signal, based on a first probe signal of the optical fiber; obtaining distortion information of the battery based on a difference between the initial Ghost mode signal and the first Ghost mode signal; and obtaining temperature change information of the battery based on a difference between the initial Bragg mode signal and the first Bragg mode signal.

[0018] The above detection method can simultaneously obtain information on local temperature changes and thickness changes of the battery cell, has a fast acquisition speed, high accuracy, realizes real-time monitoring of the state of the battery cell, and can guarantee the operation safety and stability of the battery cell.

[0019] In some embodiments, the initial Ghost mode signal is the highest intensity value M0 of the Ghost mode spectrum at time T0, and the first Ghost mode signal is the highest intensity value M1 of the Ghost mode spectrum at time T1. By calculating the difference between the highest intensity value M0 of the Ghost mode spectrum at the initial time and the highest intensity value M1 of the Ghost mode spectrum at time T1, thickness change information of the battery cell can be obtained.

[0020] In some embodiments, the initial Bragg mode signal is the wavelength λ0 corresponding to the highest intensity value of the Bragg mode spectrum at time T0, and the first Bragg mode signal is the wavelength λ1 corresponding to the highest intensity value of the Bragg mode spectrum at time T1. By calculating the difference between the wavelength λ0 corresponding to the highest intensity value of the Bragg mode spectrum at time T0 and the wavelength λ1 corresponding to the highest intensity value of the Bragg mode spectrum at time T1, the temperature change information of the battery cell can be obtained.

[0021] In some embodiments, Obtain the wavelength difference Δλ1 between the wavelength λ1 corresponding to the highest intensity value of the Bragg mode spectrum at time T1 and the wavelength λ0 corresponding to the highest intensity value of the Bragg mode spectrum at time T0, And obtain the temperature change information ΔT1 according to the step of obtaining the temperature change information ΔT1 based on the wavelength difference Δλ1. Here, the temperature change information ΔT1 is in a direct proportional relationship with the wavelength difference Δλ1, and the temperature changes by 1°C every time the Bragg mode wavelength shifts by 10 pm to 14 pm.

[0022] In some embodiments, Obtain the strain information ΔL1 according to the following steps, Obtain the intensity difference ΔM1 between the highest intensity value M0 of the Ghost mode spectrum at time T0 and the highest intensity value M1 of the Ghost mode spectrum at time T1, Obtain the stress information ΔF1 based on the intensity difference ΔM1, And obtain the strain information ΔL1 based on the stress information ΔF1 and the Young's modulus of the optical fiber. Here, the intensity difference ΔM1 and the strain information ΔF1 are in a direct proportional relationship, and the strain increases by 1 N every time the intensity decreases by 0.22 to 0.23 dB.

[0023] According to a third aspect, an embodiment of the present application provides a battery including a battery cell, a signal transmitter, a signal receiver, and a signal analyzer in any of the above embodiments. The signal transmitter is connected to the second segment of the optical fiber of the battery cell, and the signal transmitter is used to transmit a probe signal to the optical fiber. The signal receiver is connected to the second segment of the optical fiber, and the signal receiver is used to receive a status signal returned from the optical fiber. The signal analyzer is connected to the signal receiver and is used to convert the status signal into status information of the battery cell.

[0024] In the above technical solution, the signal transmitter can transmit a signal to the optical fiber, the signal receiver can receive a status signal reflected from the optical fiber, and the signal analyzer can obtain real-time temperature change and thickness change values of the battery cell by converting the status into status information according to the signal.

[0025] According to a fourth aspect, an embodiment of the present application provides a power consumption device, which includes a battery in any of the above embodiments, and the battery is used to provide electrical energy.

[0026] The above description is only an overview of the technical solution of the present application. In order to understand the technical means of the present application more clearly, it may be implemented according to the content of the specification. And in order to make the above and other objects, features and advantages of the present application more clearly and understandably, the following will specifically describe the specific embodiments of the present application.

[0027] Hereinafter, with reference to the drawings, the features, advantages and technical effects of exemplary embodiments of the present application will be described.

Brief Description of the Drawings

[0028]

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Embodiments for Carrying Out the Invention

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will clearly describe the technical solutions in the embodiments of this application while combining with the drawings in the embodiments of this application. Obviously, the described embodiments are some of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of this application.

[0030] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the technical field of this application. In this application, the terms used in the description of the application are only for describing specific embodiments and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the description of the specification, claims, and drawings of this application are intended to cover non-exclusive "including". The terms "first", "second", etc. in the description of the specification, claims, or drawings of this application are not for describing a specific order or primary-secondary relationship, but for distinguishing different objects.

[0031] The "embodiment" referred to in this application means that a specific feature, structure, or characteristic described in combination with the embodiment may be included in at least one embodiment of this application. The appearance of this phrase at each position in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments.

[0032] In the description of this application, unless otherwise specifically defined or limited, the terms "attachment", "connection", "linkage", and "installation" should be understood in a broad sense. For example, it may be a fixed connection, a removable connection, or an integral connection. It may be a direct connection or an indirect connection through an intermediate medium, or it may be a communication within two elements. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific situation.

[0033] The term "and / or" in this application is merely used to describe the relationship of relevant objects and indicates that three relationships may exist. For example, A and / or B may represent three cases: A alone, the combination of A and B, and B alone. Also, the character " / " in this application generally indicates that the relevant objects before and after are in an "or" relationship.

[0034] In the embodiments of this application, the descriptions with the same reference numerals represent the same members. For the sake of brevity, in different embodiments, the detailed descriptions of the same members are omitted. It should be understood that the dimensions such as the thickness and aspect ratio of various members in the embodiments of this application shown in the drawings, as well as the dimensions such as the thickness and aspect ratio of the entire integrated device, are only for illustrative purposes and do not constitute any limitation to this application.

[0035] The term "plurality" that appears in this application refers to two or more (including two).

[0036] In this application, the battery cell may include, for example, a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, etc., and the embodiments of this application are not limited thereto. The battery cell may exhibit a cylindrical shape, a flat shape, a rectangular parallelepiped shape, or other shapes, etc., and the embodiments of this application are not limited thereto either. Generally, battery cells are classified into three types: cylindrical battery cells, square battery cells, and pouch battery cells in a packaging manner, and the embodiments of this application are not limited thereto either.

[0037] The battery mentioned in the embodiments of this application includes one or more battery cells and is a single physical module that provides a higher voltage and capacity. For example, the battery mentioned in this application may include a battery module, a battery pack, etc. Generally, a battery includes a housing for packaging one or more battery cells. The housing can avoid the influence of liquid or other foreign substances on the charging or discharging of the battery cell.

[0038] The battery cell includes an electrode unit and an electrolyte. The electrode unit includes at least one electrode assembly, and the electrode assembly includes a positive electrode plate, a negative electrode plate, and a separator member. The battery cell operates mainly by the movement of metal ions between the positive electrode plate and the negative electrode plate. The positive electrode plate includes a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode current collector. The positive electrode current collector includes a positive electrode current collecting portion and a positive electrode convex portion protruding from the positive electrode current collecting portion. The positive electrode active material layer is coated on the positive electrode current collecting portion, and at least a part of the positive electrode convex portion is not coated with the positive electrode active material layer, and the positive electrode convex portion serves as a positive electrode tab. Taking a lithium-ion battery as an example, the material of the positive electrode current collector may be aluminum, the positive electrode active material layer includes a positive electrode active material, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, or lithium manganate, etc. The negative electrode plate includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector includes a negative electrode current collecting portion and a negative electrode convex portion protruding from the negative electrode current collecting portion. The negative electrode active material layer is coated on the negative electrode current collecting portion, and at least a part of the negative electrode convex portion is not coated with the negative electrode active material layer, and the negative electrode convex portion serves as a negative electrode tab. The material of the negative electrode current collector may be copper, the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material may be carbon or silicon, etc. To ensure that it does not fuse even when a large current flows, the number of positive electrode tabs is plural and they are laminated, and the number of negative electrode tabs is plural and they are laminated. The material of the separator member may be PP (polypropylene) or PE (polyethylene), etc. Note that the electrode assembly may have a wound structure or a laminated structure, and the embodiments of the present application are not limited thereto.

[0039] In the following embodiments, for the convenience of explanation, an example is given where the power consumption device is a vehicle.

[0040] Figure 1 is a schematic diagram of the structure of a vehicle according to some embodiments of the present application. As shown in Figure 1, a battery 2 is installed inside the vehicle 1, and the battery 2 may be installed at the bottom, head, or tail of the vehicle 1. The battery 2 may be used for power supply of the vehicle 1. For example, the battery 2 may be used as the operating power source of the vehicle 1.

[0041] The vehicle 1 may further include a controller 3 and a motor 4. The controller 3 is used to control the battery 2 to supply power to the motor 4, for example, for starting the vehicle 1, navigation, and operating power consumption requirements during driving.

[0042] In some embodiments of the present application, the battery 2 can not only be used as the operating power source of the vehicle 1, but also as the driving power source of the vehicle 1 to provide driving power to the vehicle 1 instead of gasoline or natural gas, or instead of a part of them.

[0043] Figure 2 is an exploded schematic diagram of a battery according to some embodiments of the present application. As shown in Figure 2, the battery 2 includes a housing 5 and a battery module (not shown). A plurality of battery cells constitute the battery module, and the battery module is housed in the housing 5.

[0044] The housing 5 is used to house the battery cells, and the housing 5 may have various structures. In some embodiments, the housing 5 may include a first part 51 and a second part 52. The first part 51 and the second part 52 are overlapped with each other, and the first part 51 and the second part 52 jointly define an accommodation space 53 for housing the battery cells. The second part 52 may have a hollow structure with one end open. The first part 51 has a plate-like structure, and the first part 51 is placed on the open side of the second part 52 to form the housing 5 having the accommodation space 53. Both the first part 51 and the second part 52 may have a hollow structure with one side open, and the open side of the first part 51 is placed on the open side of the second part 52 to form the housing 5 having the accommodation space 53. Of course, the first part 51 and the second part 52 may have various shapes, such as a cylindrical body, a rectangular parallelepiped, etc.

[0045] In order to improve the sealing performance after connecting the first part 51 and the second part 52, a sealing material may be installed between the first part 51 and the second part 52. For example, a sealant, a sealing ring, etc. may be installed.

[0046] Assuming that the first part 51 covers the top of the second part 52, the first part 51 is also called the upper housing lid, and the second part 52 is also called the lower housing.

[0047] In the battery 2, the number of battery cells 7 may be one or more. When there are a plurality of battery cells 7, the plurality of battery cells 7 may be connected in series, in parallel, or in series-parallel. Series-parallel connection means that there are both series connection and parallel connection in the plurality of battery cells 7. The plurality of battery cells 7 may be directly connected in series, in parallel, or in series-parallel, and the whole composed of the plurality of battery cells 7 may be housed in the housing 5. Of course, the plurality of battery cells 7 may be first connected in series, in parallel, or in series-parallel to form a battery module, and the plurality of battery modules may be connected in series, in parallel, or in series-parallel to form the whole and be housed in the housing 5.

[0048] FIG. 3 is a schematic exploded view of battery cells in a battery according to some embodiments of the present application. In some embodiments, there are a plurality of battery cells 7, and the plurality of battery cells 7 are first connected in series, in parallel, or in series-parallel to form a battery module. The plurality of battery modules are further connected in series, in parallel, or in series-parallel to form the whole and are housed in the housing. Electrical connection between the plurality of battery cells 7 in the battery module is realized through a bus bar member, so as to realize the parallel connection, series connection, or series-parallel connection of the plurality of battery cells 7 in the battery module.

[0049] The battery cell 7 of the embodiment of the present application includes an electrode unit 10, a case 20, and an end cap assembly 30. The case 20 has an opening 21, the electrode unit 10 is housed in the case 20, and the end cap assembly 30 is used to connect the case 20 and cover the opening 21.

[0050] The electrode unit 10 includes at least one electrode assembly 11. Exemplarily, the electrode unit 10 in FIG. 3 includes two electrode assemblies 11. The electrode assembly 11 includes a positive electrode plate, a negative electrode plate, and a separator member. The electrode assembly 11 may be a wound electrode assembly, a stacked electrode assembly, or other forms of electrode assemblies.

[0051] The electrode unit 10 includes at least one electrode assembly 11. That is, in the battery cell 7, the number of electrode assemblies 11 accommodated in the case 20 may be one or plural.

[0052] The battery cell 7 generally includes a housing 70. The housing 70 includes a case 20 and an end cap assembly 30. The case 20 has a hollow structure with one side open. The end cap assembly 30 covers the opening of the case 20 to form a seal connection and form an accommodation cavity for accommodating the electrode unit 10 and the electrolyte.

[0053] The end cap assembly 30 further includes electrode terminals 25. In some embodiments, two electrode terminals 25 are provided, and the two electrode terminals 25 are defined as a positive electrode terminal and a negative electrode terminal, respectively. The positive electrode terminal and the negative electrode terminal are electrically connected to the positive electrode tab portion and the negative electrode tab portion of the electrode assembly 11, respectively, and are used to output the current generated by the electrode assembly 11.

[0054] The end cap assembly 30 further includes a pressure relief mechanism 24, and the pressure relief mechanism 24 is used to release the internal pressure or temperature of the battery cell 7 when the internal pressure or temperature of the battery cell 7 reaches a predetermined value. Exemplarily, the pressure relief mechanism 24 is located between the positive electrode terminal and the negative electrode terminal, and the pressure relief mechanism 24 may be a member such as an explosion-proof valve, an explosion-proof sheet, a gas valve, a pressure relief valve, or a safety valve.

[0055] In some embodiments, the case 20 may have a hollow structure with openings on both opposite sides. The end cap assembly 30 includes two end cap assemblies 30, and the two end cap assemblies 30 are respectively sealed and connected to cover the two openings of the case 20 to form an accommodation cavity for accommodating the electrode unit 10 and the electrolyte. In some examples, the positive electrode terminal and the negative electrode terminal may be mounted on the same end cap assembly 30. In another example, the positive electrode terminal and the negative electrode terminal are respectively mounted on the two end cap assemblies 30.

[0056] During the operation process of the battery cell 7, the temperature of the electrode assembly 11 gradually increases. When the temperature of the electrode assembly 11 rises to a certain level, the internal pressure of the electrode assembly also increases, and the stability of the internal environment of the case 20 significantly decreases. At the same time, the crystallization on the surface of the electrode assembly 11 causes the thickness thereof to tend to increase. When the crystallization on the surface of the electrode assembly reaches a certain degree, there is a possibility of breaking through the separator and causing a short circuit inside the electrode assembly. Moreover, when the thickness of the electrode assembly 11 increases to a certain degree, it causes deformation of the case 20 and uneven distribution of the electrode liquid, which similarly causes instability in the operation of the battery cell 7 and leads to safety accidents.

[0057] In view of the above problems, the inventor designed a battery cell including a housing, an electrode assembly, and an optical fiber. The electrode assembly is accommodated within the housing. In the technical solution of the embodiment of the present application, the optical fiber includes a first segment and a second segment that are connected to each other. The first segment is bonded to the electrode assembly, which can improve the detection sensitivity of the optical fiber to the temperature or strain of the electrode assembly and improve the accuracy and efficiency of the state monitoring of the battery cell. The second segment extends outside the housing and is used to transmit the internal state information of the electrode assembly to the outside. The axes of the first segment and the second segment are alternately arranged, and the second segment does not contact the electrode assembly, and due to the photo-thermal effect, it causes changes in the central wavelength of the Bragg mode and the central wavelength of the Ghost mode of the single-mode optical fiber. The above changes can reflect the change in the thickness and the change in the surface temperature of the electrode assembly. Therefore, the above structure realizes the simultaneous monitoring of the temperature change and the strain of the battery cell and can improve the operation safety and stability of the battery cell.

[0058] Hereinafter, Figures 4 to 7 will continue to be referred to. Figure 4 is a schematic structural diagram of an optical fiber 8 of a battery cell 7 according to an embodiment of the present application. Figure 5 is a spectrum diagram of the optical fiber 8 of the battery cell 7 according to an embodiment of the present application. Figure 6 is a schematic structural diagram of the optical fiber 8 of the battery cell 7 according to an embodiment of the present application. Figure 7 is a schematic connection structure diagram of a tape 83 and a third segment of the battery cell 7 according to an embodiment of the present application.

[0059] Referring to FIGS. 3 to 5 together, an embodiment of the present application provides a battery cell 7 including a housing, an electrode assembly 11, and an optical fiber 8. The electrode assembly 11 is housed within the housing. The optical fiber 8 includes a first segment 81 and a second segment 82. The first segment 81 is bonded to the electrode assembly 11, and the second segment 82 is connected to the first segment 81 and extends outside the housing, and the axes of the first segment 81 and the second segment 82 are alternately arranged. The optical fiber 8 is used to acquire the state signal of the battery cell 7.

[0060] Exemplarily, the optical fiber 8 may be a single-mode optical fiber. During the operation process of the battery 2, when temperature and thickness changes occur near the monitoring point of the optical fiber 8, the optical field of the core mode of the optical fiber 8 is modulated, and changes in the central wavelength of the Bragg mode spectrum and the intensity of the Ghost mode as shown in FIG. 5 appear on the spectrum demodulator. Since the axes of the first segment 81 and the second segment 82 of the optical fiber 8 are alternately arranged, the second segment 82 contacts the surface of the measurement target position of the electrode assembly 11, and the intensity of the Ghost mode in its spectrum exhibits a linear response to strain. Since the second segment 82 does not contact the surface of the measurement target position of the electrode assembly 11, the influence of strain on the Bragg mode wavelength of the single-mode optical fiber 8 is avoided. Therefore, the strain situation of this measurement target position can be analyzed by observing the change in the intensity of the Ghost mode.

[0061] Furthermore, due to the thermo-optical effect, the temperature change of the electrode assembly 11 causes simultaneous drift of the Bragg mode central wavelength and the Ghost mode central wavelength of the optical fiber 8, but only the Bragg mode wavelength drift caused by the temperature change is linear. Therefore, the temperature change situation of the measurement target part can be obtained by analyzing the change in the Bragg mode central wavelength.

[0062] In the technical solution of the embodiment of the present application, the optical fiber 8 includes a first segment 81 and a second segment 82 that are connected to each other. The first segment 81 is bonded to the electrode assembly 11, which can improve the detection sensitivity of the optical fiber 8 to the temperature or strain of the electrode assembly 11, and can improve the accuracy and efficiency of the state monitoring of the battery cell 7. The second segment 82 extends outside the housing and is used to transmit the internal state information of the electrode assembly 11 to the outside. The axes of the first segment 81 and the second segment 82 are alternately installed, and the second segment 82 does not contact the electrode assembly 11. Due to the photo-thermal effect, the change in the central wavelength of the Bragg mode and the central wavelength of the Ghost mode of the single-mode optical fiber 8 is caused. The above changes can reflect the change in the thickness and the surface temperature of the electrode assembly 11. Therefore, the above structure can realize the simultaneous monitoring of the temperature change and strain of the battery cell 7, and can improve the operation safety and stability of the battery cell 7.

[0063] In some embodiments of the present application, the diameter of the first segment 81 is not equal to the diameter of the second segment 82, or the diameter of the first segment 81 is equal to the diameter of the second segment 82. In the above technical solution, the equal diameters of the first segment 81 and the second segment 82 can facilitate the manufacture and assembly of the optical fiber 8. The unequal diameters of the first segment 81 and the second segment 82 can facilitate the connection of one second segment 82 to a plurality of first segments 81 at the same time, and it is easy to monitor a plurality of monitoring points at the same time. The above structure may be installed as required and is not limited here.

[0064] As shown in FIG. 5, in some embodiments of the present application, the state signal acquired by the optical fiber 8 includes a Ghost signal X and a Bragg signal Y. The Ghost signal X is used to acquire the strain information of the battery cell 7, and the Bragg signal Y is used to acquire the temperature information of the battery cell 7. By acquiring the change status of the Ghost signal X and the Bragg signal Y in the single-mode optical fiber 8, the temperature change and strain of the electrode assembly are analyzed. The above signals have high test sensitivity to the strain and temperature changes of the battery cell 7, and a fast response speed, and can effectively monitor the changes in the state information of the battery cell 7.

[0065] In some embodiments of the present application, the length of the second segment 82 is L1, and 1 mm ≤ L1 ≤ 2 cm. The second segment 82 may be a communication silica optical fiber and is used to connect the spectrum demodulation system. By setting a reasonable length of the second segment 82, it is possible to ensure the transmission of the information collected in the first segment 81, and at the same time reduce the space occupied by the second segment 82.

[0066] In some embodiments of the present application, the first segment 81 and the second segment 82 are connected by a welding method. The welding connection method can ensure the stability of signal transmission in the optical fiber 8 and the strength of the connection between the first segment 81 and the second segment 82. At the same time, the melting operation is simple and the connection efficiency is high.

[0067] As shown in FIG. 6, in some embodiments of the present application, the optical fiber 8 further includes a third segment. The third segment is connected to one end of the first segment 81 away from the second segment 82, and a Bragg grating is provided on the third segment.

[0068] The Bragg grating includes a plurality of refractive members arranged inside the third segment according to a certain rule, and the Bragg grating of the optical fiber 8 serves to selectively retroreflect a single wavelength from the wavelength band propagating from the optical fiber 8. By installing the Bragg grating, spectral information including the Bragg mode and the Ghost mode can be obtained. The change in the Ghost mode intensity of the Bragg grating spectrum exhibits a certain response relationship with strain, and the drift of the Bragg wavelength in the Bragg grating spectrum exhibits a certain response relationship with temperature. The spectrum demodulator simultaneously analyzes the spectra of these two modes, thereby simultaneously acquiring the strain and temperature change information of the battery cell 7 to be measured.

[0069] As shown in FIG. 7, in some embodiments of the present application, between the third segment and the electrode assembly 11 is adhered by a tape 83. By connecting with the tape 83, the stability of the connection between the third segment and the electrode assembly 11 can be guaranteed, and the accuracy of the optical fiber 8 to acquire information can be improved.

[0070] In some embodiments of the present application, between the third segment and the second segment 82 is an integrally formed structure. The above structure can improve the manufacturing efficiency of the third segment.

[0071] In some embodiments of the present application, the length of the third segment is L2, and 1 mm ≤ L2 ≤ 5 cm. By setting a reasonable length of the third segment, the accuracy of the spectral signal can be guaranteed, and at the same time, the occupied space of the third segment can be made as small as possible.

[0072] In some embodiments of the present application, the electrode assembly 11 includes electrode plates and separators that are stacked and installed, and at least a part of the third segment is provided between the electrode plate and the separator of the battery cell 7, or at least a part of the third segment is provided between two separators of the battery cell 7. The optical fiber 8 is installed at the above position, and can more accurately obtain the local temperature and thickness change conditions during the operation of the battery cell 7, further improving the monitoring efficiency and accuracy of the battery cell 7.

[0073] In some embodiments of the present application, the number of the second segments 82 is plural, and the plural second segments 82 are connected to at least one first segment 81, and each second segment 82 is respectively connected to at least one electrode assembly 11.

[0074] In some other embodiments of the present application, the number of the second segments 82 is plural, the plural second segments 82 are connected to at least one first segment 81, and the plural second segments 82 are all installed at different positions of the same electrode assembly 11.

[0075] Each second segment 82 can obtain the information of at least one monitoring point, and the plural second segments 82 can obtain plural monitoring information simultaneously. The above structure can install plural monitoring points on the same battery cell 7, or install monitoring points on plural battery cells 7 respectively. The same first segment 81 can be connected to the plural second segments 82. The above structure increases the monitoring points of the battery cell 7, simplifies the structure of the first segment 81, ensures the transmission of the spectral signal, simplifies the structure of the optical fiber 8, and improves the efficiency of information transmission.

[0076] In some embodiments, the optical fiber 8 is a single-mode optical fiber, and the single-mode optical fiber includes a core and a protective layer disposed around the core. The core diameter is 4 μm (micrometers) or more and 9 μm or less. Optionally, the core diameter is 9 μm.

[0077] In some embodiments, the intersection distance H between the axis of the first segment 81 and the axis of the second segment 82 is 4 μm ≤ H ≤ 9 μm. The intersection distance between the axis of the first segment 81 and the axis of the second segment 82 should be set within a reasonable range to ensure the stability of signal transmission and, at the same time, ensure that different-intensity Ghost signals can be obtained when the light ray is subjected to stress. Therefore, the intersection of the axis of the first segment 81 and the axis of the second segment 82 should not exceed the core diameter of the single-mode optical fiber.

[0078] As shown in FIG. 8, the embodiment of the present application further provides a method for monitoring a battery cell for monitoring the state information of the battery cell 7. The monitoring method of the battery 2 is In S01, based on the initial probe signal of the optical fiber, obtaining the initial state information of the battery cell, including the initial Ghost mode signal and the initial Bragg mode signal; In S02, based on the first probe signal of the optical fiber, obtaining the first state information of the battery cell, including the first Ghost mode signal and the first Bragg mode signal; In S03, obtaining the strain information of the battery 2 based on the difference between the initial Ghost mode signal and the first Ghost mode signal; In S04, obtaining the temperature change information of the battery 2 based on the difference between the initial Bragg mode signal and the first Bragg mode signal.

[0079] The above detection method can simultaneously obtain information on local temperature changes and thickness changes of the battery cell 7, has a high acquisition speed and high accuracy, realizes real-time monitoring of the state of the battery cell 7, and can ensure the operation safety and stability of the battery cell 7.

[0080] In some embodiments of the present application, the initial Ghost mode signal is the maximum intensity value M0 of the Ghost mode spectrum at time T0, and the first Ghost mode signal is the maximum intensity value M1 of the Ghost mode spectrum at time T1. By calculating the difference between the maximum intensity value M0 of the Ghost mode spectrum at the initial time and the maximum intensity value M1 of the Ghost mode spectrum at time T1, the thickness change information of the battery cell 7 can be obtained.

[0081] In some embodiments of the present application, the initial Bragg mode signal is the wavelength λ0 corresponding to the maximum intensity value of the Bragg mode spectrum at time T0, and the first Bragg mode signal is the wavelength λ1 corresponding to the maximum intensity value of the Bragg mode spectrum at time T1. By calculating the difference between the wavelength λ0 corresponding to the maximum intensity value of the Bragg mode spectrum at time T0 and the wavelength λ1 corresponding to the maximum intensity value of the Bragg mode spectrum at time T1, the temperature change information of the battery cell 7 can be obtained.

[0082] In some embodiments of the present application, obtain the wavelength difference Δλ1 between the wavelength λ1 corresponding to the maximum intensity value of the Bragg mode spectrum at time T1 and the wavelength λ0 corresponding to the maximum intensity value of the Bragg mode spectrum at time T0, and obtain the temperature change information ΔT1 based on the wavelength difference Δλ1. Here, the temperature change information ΔT1 is in a direct proportional relationship with the wavelength difference Δλ1, and the temperature changes by 1 °C every time the Bragg mode wavelength shifts by 10 pm to 14 pm.

[0083] In some embodiments of the present application, obtain the strain information ΔL1 by the following steps, Obtain the intensity difference ΔM1 between the maximum intensity value M0 of the Ghost mode spectrum at time T0 and the maximum intensity value M1 of the Ghost mode spectrum at time T1. Obtain stress information ΔF1 based on the intensity difference ΔM1. Obtain strain information ΔL1 based on the stress information ΔF1 and the Young's modulus of the optical fiber. Here, the intensity difference ΔM1 and the strain information ΔF1 are in a direct proportional relationship, and for every 0.22 - 0.23 dB decrease in intensity, the strain increases by 1 N. Exemplarily, the strain information ΔL1 (unit is με) = ΔF1 / A * 1000, where A in the formula represents the Young's modulus of the optical fiber.

[0084] In the embodiments of the present application, in the spectral information including the Bragg mode and the Ghost mode obtained by the optical fiber 8, there are the following various situations: First, the peaks of the Bragg mode and the Ghost mode shift, but the maximum intensity value of the Ghost mode spectrum does not change. In this case, it is determined that the temperature at the monitoring point has changed, but no strain has occurred.

[0085] Second, the peaks of the Bragg mode and the Ghost mode shift and the maximum intensity value of the Ghost mode spectrum decreases. As can be understood, when the maximum intensity value of the Ghost mode spectrum changes, it can be determined that strain has occurred. Further, 1) when Δλ = 0, it can be determined that only strain has occurred at the monitoring point and no temperature change has occurred, 2) when Δλ > 0, it can be determined that both a temperature change and strain have occurred at the monitoring point. At this time, first, the shift amount ΔX of the Ghost mode peak and the Bragg mode peak generated corresponding to the amount of strain and the influence on the strain spectrum may be calculated. Next, when calculating the temperature change corresponding to the monitoring point, the shift amount ΔX of the peak due to the above strain should be subtracted from the actual shift amount, that is, the shift amount Δλ of the Bragg mode peak due to the temperature change.

[0086] The embodiments of the present application further provide a battery 2, which includes the battery cell 7, the signal transmitter, the signal receiver, and the signal analyzer in any of the above embodiments. The signal transmitter is connected to the second segment 82 of the optical fiber 8 of the battery cell 7, and the signal transmitter is used to transmit a probe signal to the optical fiber 8. The signal receiver is connected to the second segment 82 of the optical fiber 8, and the signal receiver is used to receive the status signal returned from the optical fiber 8. The signal analyzer is connected to the signal receiver and is used to convert the status signal into the status information of the battery cell 7.

[0087] In the above technical solution, the signal transmitter can transmit a signal to the optical fiber 8, the signal receiver can receive the status signal reflected from the optical fiber 8, and the signal analyzer can convert the status into status information according to the signal, so as to obtain the real-time temperature change and thickness change values of the battery cell 7.

[0088] The embodiments of the present application further provide a power consumption device, which includes the battery 2 in any of the above embodiments, and the battery 2 is used to provide electrical energy.

[0089] Since the battery 2 and the power consumption device in the present application both include the battery cell 7 in the embodiments of the present application, therefore, the above structure can realize simultaneously monitoring the temperature change and distortion of the battery cell 7, and can improve the operation safety and stability of the battery cell 7, which will not be further described here.

[0090] Embodiment 1 This embodiment provides a battery cell and a method for monitoring the battery cell. The battery cell includes a housing, an electrode assembly, and an optical fiber. The electrode assembly is housed within the housing. The optical fiber includes a first segment and a second segment. The first segment is bonded to the electrode assembly. The second segment is connected to the first segment and extends outside the housing. The axes of the first segment and the second segment are alternately arranged. The optical fiber is used to acquire the state signal of the battery cell. The state signal acquired by the optical fiber includes a Ghost signal X and a Bragg signal Y. The Ghost signal is used to acquire the strain information of the battery cell. The Bragg signal is used to acquire the temperature information of the battery cell. The length of the second segment is L1, where 1 mm ≤ L1 ≤ 2 cm. The first segment and the second segment are connected by a welding method. The optical fiber further includes a third segment. The third segment is connected to one end of the first segment away from the second segment. A Bragg grating is provided on the third segment. The third segment and the electrode assembly are adhered by a tape. The third segment and the second segment have an integrally formed structure. The length of the third segment is L2, where 1 mm ≤ L2 ≤ 5 cm. The electrode assembly includes electrode plates and separators that are stacked and installed. At least a part of the third segment is provided between two separators of the battery cell.

[0091] One end of the first segment away from the case is connected to a signal transmitter device, a signal receiver device, and a signal analysis device respectively. The signal transmitter device can transmit a signal to the optical fiber. The signal receiver device can receive the state signal reflected from the optical fiber. The signal analysis device acquires the real-time temperature change and thickness change values of the battery cell by converting the state into state information according to the signal.

[0092] A signal transmitter transmits a signal to an optical fiber, and a temperature sensor is installed in a battery cell to obtain the real-time temperature of the electrode assembly. As shown in FIG. 9, a signal receiver obtains Ghost mode signals and Bragg mode signals at different temperatures.

[0093] As can be seen from FIG. 9, with the increase in temperature, there is no significant change in the intensity of the Ghost mode, nor is there a significant change in the intensity of the Bragg mode. However, the significant drift of the wavelength with respect to the temperature change varies linearly. Referring also to FIG. 10, line Z is a fitting curve based on the temperature change of the Bragg wave peak in FIG. 9. The Bragg wave peak shifts to the right with the increase in temperature, and its sensitivity shifts by about 12 pm (picometers) per degree Celsius.

[0094] Example 2 This example provides a battery cell and a method for monitoring the battery cell. The battery cell in this example is the same as that in Example 1, and a temperature sensor is not installed in the battery cell in this example.

[0095] Charge and discharge operations are performed on the battery cell using three different rates, and a signal device obtains probe signals of different times of the optical fiber and converts the probe signals into temperature signals. The monitoring results are as shown in Table 1.

[0096]

Table 1

[0097] Referring to FIGS. 11 to 13 together, FIGS. 11 to 13 are temperature change spectra in the charge and discharge process of the battery cell at different charge and discharge rates.

[0098] FIG. 11 shows a curve of the temperature of the battery cell changing with the voltage change at a charge and discharge rate of 0.33C. With the increase in voltage, the battery cell exhibits a significant increase in temperature, and with the decrease in voltage, the temperature of the battery cell also decreases.

[0099] Figure 12 shows a curve in which the temperature of the battery cell changes with the voltage change at a 0.75C charge-discharge rate. As the voltage increases, the battery cell exhibits a significant temperature increase, and as the voltage decreases, the temperature of the battery cell also decreases.

[0100] Figure 13 shows a curve in which the temperature of the battery cell changes with the voltage change at a 1.0C charge-discharge rate. As the voltage increases, the battery cell exhibits a significant temperature increase, and as the voltage decreases, the temperature of the battery cell also decreases.

[0101] The above experimental results are consistent with the actual temperature change rule of the battery cell. Therefore, the battery cell according to the embodiment of the present application can accurately and efficiently monitor the change of the battery cell temperature. The safety and stability of the operation of the battery cell can be guaranteed. Moreover, the battery cell of the present application has a simple structure and is easy to popularize and apply.

[0102] Example 3 This embodiment provides a battery cell and a method for monitoring the battery cell. The battery cell in this embodiment is the same as that in Embodiment 1, and a temperature sensor is not installed in the battery cell in this embodiment.

[0103] A signal is transmitted to the optical fiber by a signal transmitting device, and different magnitudes of pressure are applied to the battery cell. As shown in Figure 14, a Ghost mode signal and a Bragg mode signal at different pressures are acquired by a signal receiving device.

[0104] As can be seen from Figure 14, as the pressure increases, both the Ghost mode peak and the Bragg peak mode have a certain drift. Moreover, the intensity of the Bragg mode also changes significantly, while the intensity of the Ghost mode shows a tendency to gradually decrease with the increase of pressure. Referring to Figure 15 together, line W is a fitting curve based on the pressure change of the Ghost mode peak intensity in Figure 14. The intensity of the Ghost mode peak shifts downward with the increase of pressure, and its sensitivity decreases by about 0.222 dB for every 1N increase.

[0105] Example 4 This example provides a battery cell and a method for monitoring the battery cell. The battery cell in this example is the same as that in Example 1, and a temperature sensor is not installed in the battery cell in this example.

[0106] Charge and discharge operations are performed on the battery cell using three different rates, and different-time probe signals of the optical fiber are obtained by a signal device, and the probe signals are converted into pressure signals. The monitoring results are as shown in Table 2.

[0107] [Table 2]

[0108] Referring to FIGS. 16 to 18 together, FIGS. 16 to 18 are the strain change spectra in the charge and discharge process of the battery cell at different charge and discharge rates. Strain calculation formula: ΔL1 = ΔF1 / A * 1000, where ΔL1 in the formula represents the strain at the monitoring point, ΔF1 represents the stress at a single monitoring point, and A represents the Young's modulus of the optical fiber. The Young's modulus of the optical fiber in this example is 70.

[0109] FIG. 16 shows the curve of the stress of the battery cell changing with the voltage change at a 0.33C charge and discharge rate. It is calculated by the stress-strain conversion formula. As the voltage increases, the battery cell shows a significant increase in strain, and as the voltage decreases, the strain of the battery cell also decreases accordingly.

[0110] FIG. 17 shows the curve of the stress of the battery cell changing with the voltage change at a 0.75C charge and discharge rate. It is calculated by the stress-strain conversion formula. As the voltage increases, the battery cell shows a significant increase in strain, and as the voltage decreases, the strain of the battery cell also decreases accordingly.

[0111] FIG. 18 shows a curve in which the stress of a battery cell changes with a change in voltage at a 1.0C charge-discharge rate. It was calculated by a stress-strain conversion formula. As the voltage increases, the battery cell exhibits a significant increase in strain, and as the voltage decreases, the strain of the battery cell also decreases accordingly.

[0112] The above experimental results are consistent with the actual strain change rule of the battery cell. Therefore, the battery cell according to the embodiment of the present application can accurately and efficiently monitor the change in the strain of the battery cell. The safety and stability of the operation of the battery cell can be guaranteed. Moreover, the battery cell of the present application has a simple structure and is easy to popularize and apply.

[0113] The present application has been described with reference to preferred embodiments, but various improvements can be made thereto without departing from the scope of the present application, and the members thereof can be replaced with equivalents. In particular, as long as there is no structural collision, each technical feature mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the specification, but includes all technical solutions included within the scope of the claims.

Description of Reference Numerals

[0114] 1: Vehicle, 10: Electrode unit, 11: Electrode assembly, 2: Battery, 20: Case, 21: Opening, 24: Pressure relief mechanism, 25: Electrode terminal, 3: Controller, X: Ghost signal, Y: Bragg signal, 4: Motor, 5: Housing, 51: First part, 52: Second part, 53: Accommodation space, 7: Battery cell, 8: Optical fiber, 81: First segment, 82: Second segment, 83: Tape.

Claims

1. A battery cell, comprising: a housing; an electrode assembly housed within the housing; and an optical fiber including a first segment and a second segment, wherein the first segment is bonded to the electrode assembly, the second segment is connected to the first segment and extends outside the housing, and the axes of the first segment and the second segment are alternately arranged, and the optical fiber is used to obtain a state signal of the battery cell.

2. The state signal includes a Ghost signal and a Bragg signal, the Ghost signal is used to obtain strain information of the battery cell, and the Bragg signal is used to obtain temperature information of the battery cell. The battery cell according to claim 1.

3. The diameter of the first segment is not equal to the diameter of the second segment, or the diameter of the first segment is equal to the diameter of the second segment. The battery cell according to claim 2.

4. The length of the second segment is L １ where 1 mm ≤ L １ ≤ 2 cm. The battery cell according to claim 2

5. The first segment and the second segment are connected by welding. The battery cell according to claim 2.

6. The optical fiber further includes a third segment, the third segment is connected to an end of the first segment away from the second segment, and a Bragg grating is provided on the third segment. The battery cell according to claim 2.

7. The third segment and the second segment have an integrally formed structure. The battery cell according to claim 6.

8. The length of the third segment is L ２ where 1 mm ≤ L ２ ≤ 5 cm, the battery cell according to claim 6

9. The electrode assembly includes electrode plates and separators stacked thereon, and at least a part of the third segment is provided between the electrode plates and the separators of the battery cell, or at least a part of the third segment is provided between two separators of the battery cell. The battery cell according to any one of claims 6 to 8.

10. The number of the second segments is plural, the plural second segments are connected to at least one first segment, and each second segment is connected to at least one electrode assembly respectively. The battery cell according to claim 9.

11. A method for monitoring a battery cell, which is used for monitoring the state information of the battery cell, and the monitoring method includes: Obtaining initial state information of the battery cell, including an initial Ghost mode signal and an initial Bragg mode signal, based on an initial probe signal of an optical fiber; Obtaining first state information of the battery cell, including a first Ghost mode signal and a first Bragg mode signal, based on a first probe signal of the optical fiber; Obtaining strain information of the battery based on a difference between the initial Ghost mode signal and the first Ghost mode signal; Obtaining temperature change information of the battery based on a difference between the initial Bragg mode signal and the first Bragg mode signal. A method for monitoring a battery cell includes the above steps.

12. The initial Ghost mode signal is T ０ the maximum intensity value M of the Ghost mode spectrum at the time ０ and is The first Ghost mode signal is T １ the maximum intensity value M of the Ghost mode spectrum at time １ The monitoring method according to claim 11, wherein the monitoring method is as described above.

13. The initial Bragg mode signal is T ０ the wavelength λ corresponding to the highest intensity value of the Bragg mode spectrum at time T ０ and is The first Bragg mode signal is T １ The wavelength λ corresponding to the highest intensity value of the Bragg mode spectrum at time １ The monitoring method according to claim 11, which is

14. T １ The wavelength λ corresponding to the maximum intensity value of the Bragg mode spectrum at time T １ and T ０ The wavelength λ corresponding to the maximum intensity value of the Bragg mode spectrum at time T ０ The wavelength difference Δλ between them １ is obtained, the wavelength difference Δλ １ Based on this, temperature change information ΔT １ is obtained through steps, and the temperature change information ΔT １ is obtained. Here, the temperature change information ΔT １ is in a directly proportional relationship with the wavelength difference Δλ １ and for every 1 °C change in temperature, the Bragg mode wavelength shifts by 10 pm to 14 pm. The monitoring method according to any one of claims 11 to 13.

15. Obtain the strain information ΔL by the following steps １ and T ０ The maximum intensity value M of the Ghost mode spectrum at time T ０ and T １ The maximum intensity value M of the Ghost mode spectrum at time T １ The intensity difference ΔM between them １ is obtained, the intensity difference ΔM １ Based on this, stress information ΔF １ is obtained, the stress information ΔF １ and the strain information ΔL based on the Young's modulus of the optical fiber １ are obtained, Here, the intensity difference ΔM １ and the strain information ΔF １ are in a direct proportional relationship, and for every 0.22 to 0.23 dB decrease in intensity, the strain increases by 1 N The monitoring method according to any one of Claims 12 to 14.

16. A battery, including: The battery cell according to any one of Claims 1 to 10; A signal transmitter device connected to a second segment of an optical fiber of the battery cell, and the signal transmitter device is used for transmitting a probe signal to the optical fiber; A signal receiver device connected to a second segment of the optical fiber, and the signal receiver device is used for receiving a state signal returned from the optical fiber; A signal analysis device connected to the signal receiver device, and the signal analysis device is used for converting the state signal into state information of the battery cell. A battery includes the above components.

17. A power consumption device including the battery according to Claim 16, and the battery is used for providing electrical energy.

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