Battery cells, battery modules, and battery packs

Abstract

A battery cell (2000), a battery module, and a battery pack (1000). The battery cell (2000) includes a battery cell body (200) and an optical fiber (10), wherein a plurality of grating temperature measurement points (11) are formed on the optical fiber (10), and the optical fiber (10) is disposed on the battery cell body (200).

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This disclosure claims priority to Chinese Patent Application No. 202222451774.9, entitled "Battery Cell, Battery Module, and Battery Pack," filed on September 15, 2022. The entire contents of the above application are incorporated herein by reference.

[0002] Technical Field The present disclosure relates to the technical field of cells, and more particularly to cells, battery modules, and battery packs. [Background technology]

[0003] In related art, battery temperature is primarily detected through multiple thermistors. Relatively few data points are provided for temperature collection, and these have a single configuration and can only be placed at the end of the cell. The collected data is single, making it difficult to collect the maximum and minimum temperatures within the cell. Additionally, data collection is susceptible to electromagnetic interference, resulting in data drift, reduced test accuracy, and significant placement difficulties. Summary of the Invention [Means for solving the problem]

[0004] The present disclosure aims to solve at least one of the technical problems in the related art. Therefore, an object of the present disclosure is to provide a cell. To perform temperature measurement on the cell with high temperature measurement accuracy, low environmental impact, reasonable space occupation, and convenient placement, grid temperature measurement points are arranged on the cell body.

[0005] The present disclosure further provides a battery module having the above-described cell.

[0006] The present disclosure further provides a battery pack having the above battery module.

[0007] A cell according to the present disclosure includes a cell body and an optical fiber, wherein a plurality of grating temperature measurement points are formed on the optical fiber, and the optical fiber is disposed on the cell body.

[0008] In the cell according to the present disclosure, lattice temperature measurement points are arranged on the cell body to perform temperature measurements on the cell. In this way, on the one hand, the number and arrangement of lattice temperature measurement points are more reasonable, data samples are more abundant, and cell temperature measurement is more accurate, providing preparation for subsequent cell temperature control. On the other hand, optical fiber has a small geometric size, is less restricted by physical structure, is less difficult to arrange, can be arranged without changing the cell structure, and is not affected by electromagnetic interference. Thus, collection precision is high and data is accurate.

[0009] A battery module according to the present disclosure includes a plurality of the cells described above.

[0010] A battery pack according to the present disclosure includes the battery module described above.

[0011] Additional aspects and advantages of the disclosure will be set forth in part in the description that follows, and in part will be apparent from the description, or may be learned through practice of the disclosure. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram of a battery pack according to one embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic diagram of a fit between a temperature measurement assembly and a cell according to a first embodiment of the present disclosure. [Figure 3] FIG. 10 is a schematic diagram of a fit between a temperature measurement assembly and a cell according to a second embodiment of the present disclosure. [Explanation of symbols]

[0013] Battery pack 1000; cell 2000 Temperature measurement assembly 100, cell body 200 Optical fiber 10, optical fiber temperature measurement point 11, first section 12, second section 13 Computer 20 Housing 210 and bare cell 220 DETAILED DESCRIPTION OF THE INVENTION

[0014]

[0023] The embodiments of the present disclosure will be described in detail below. Examples of the embodiments are shown in the accompanying drawings. The same or similar elements or elements having the same or similar functions are designated by the same or similar reference numerals throughout the description. The embodiments described below with reference to the accompanying drawings are examples and are used only to explain the present disclosure and cannot be construed as limitations on the present disclosure.

[0015] A cell 2000, a battery module, and a battery pack 1000 according to an embodiment of the present disclosure will now be described with reference to FIGS.

[0016] As shown in FIGS. 1, 2, and 3, a cell 2000 according to an embodiment of the first aspect of the present disclosure includes a cell body 200 and an optical fiber 10.

[0017] A plurality of grating temperature measurement points 11 are formed in the optical fiber 10 .

[0018] In the present disclosure, the optical fiber 10 is disposed on the cell body 200, and a grating is previously engraved on the optical fiber 10 as the grating temperature measurement points 11. The optical fiber 10 can be signal-connected to a computer 20 disposed outside the cell 2000 to form a temperature measurement assembly 100. In other words, the temperature measurement assembly 100 includes the optical fiber 10 and the computer 20. The optical fiber 10 is disposed on the cell body 200. The computer 20 is connected to the input and output terminals of the optical fiber 10. The computer 20 includes at least a signal source and a demodulator to convert the optical signal into a temperature signal and realize temperature measurement of the cell body 2000. It should be understood that the battery pack 1000 includes a plurality of cells 2000. The battery pack 1000 further includes a thermal management system for performing thermal management on the cells 2000. The computer 20 is disposed outside the cell 2000 and is constructed as part of the thermal management system.

[0019] It should be noted that a grating is an optical device consisting of a number of parallel slits with regularly varying spacing, such as an equidistant grating with the same spacing width in the form of parallel slits. The number of parallel slits with regularly varying spacing is inscribed on the fiber core of the optical fiber 10 through the photosensitivity of the material of the optical fiber 10 to form a grating. However, the flexibility of using gratings lies in their ability to achieve multi-point sensing. In theory, countless gratings with different wavelengths can be inscribed within a single optical fiber 10 to achieve distributed monitoring of the same or multiple physical parameters. An optical fiber 10 with multiple gratings inscribed on it is formed as an optical fiber grating string. By accurately positioning the distance between two reflection points, lightwave signals that meet the conditions are reflected by the grating, while signals with different wavelengths are not substantially reflected. By connecting the grating to a demodulator, the lightwave wavelengths of the independent radiation waves emitted by the signal source can be measured. When the grating is affected by temperature or stress field changes, the grating pitch changes, and the wavelength of the reflected wave also changes accordingly, resulting in different wavelengths being emitted, thereby achieving the temperature measurement function of the grating temperature measurement point 11 based on the different wavelengths.

[0020] Based on the above, the lattice temperature measurement points 11 are arranged in areas with intense temperature changes and in areas where temperature needs to be collected according to the size and thermal field distribution of the cell body 200 (for example, as shown in Figures 2 and 3, multiple lattice temperature measurement points 11 are arranged equidistantly along the height and length of the cell body 200). In addition, the optical fiber 10 has a small geometric size, with a diameter of only a few hundred microns. This not only overcomes the physical constraints imposed by the stacked structure of the busbar and cell body 200, but also reduces the constraints, thereby realizing various forms of arrangement and rational placement of the lattice temperature measurement points 11. A larger sample volume indicates more abundant collected data, allowing the highest and lowest temperatures of the cell body 200 to be collected and the locations of the highest and lowest temperature points to be determined. A larger sample volume indicates more accurate temperature measurement of the cell 200, which makes subsequent temperature control of the cell body 200 easier. Furthermore, temperature measurement through the optical fiber 10 is not affected by electromagnetic interference, resulting in more accurate data and higher collection accuracy.

[0021] In the cell 2000 according to the embodiment of the present disclosure, the lattice temperature measurement points 11 are arranged on the cell body 200 to perform temperature measurements on the cell body 200. In this way, on the one hand, the number and arrangement positions of the lattice temperature measurement points 11 may be more reasonable, and data samples may be more abundant, which facilitates temperature control of the cell body 200. On the other hand, the optical fiber 10 has a small geometric size, is less restricted by the physical structure, is less difficult to arrange, can be arranged without changing the structure of the cell body 200, and is not affected by electromagnetic interference. In this way, the collection precision is high and the data is accurate.

[0022] 2 and 3 , according to some embodiments of the present disclosure, the cell body 200 includes a housing 210 and a bare cell 220 disposed within the housing 210. The optical fiber 10 is disposed on the housing 210 or the bare cell 220.

[0023] The cell body 200 and the optical fiber 10 may be secured in a number of ways, for example using a thermally conductive structural adhesive, or the optical fiber 10 is secured to the bare cell 220 or housing 210 through the arrangement of fixed supports, fixing grooves, etc.

[0024] Illustratively, as shown in FIG. 3, the optical fiber 10 is disposed on a side of the housing 210 facing the bare cell 220, and / or the optical fiber 10 is disposed on a side of the housing 210 opposite the bare cell 220. Specifically, the side can be defined together by the height direction and length direction shown in FIG.

[0025] In some embodiments, the housing 210 has a large cell surface facing or opposite the bare cell 220. The optical fiber 10 is disposed on the large cell surface. Alternatively, the outer surface of the bare cell 220 may have the large cell surface. The optical fiber 10 may be disposed on the large cell surface of the bare cell 220. It should be understood that the bare cell 220, the housing 210, or the cell body 200 may have multiple surfaces. The large cell surface refers to the surface having the largest area among all surfaces of the bare cell 220, the housing 210, or the cell body 200.

[0026] Based on the above, the temperature of the cell body 200 can be measured directly or indirectly, and the temperature of the bare cell 220 or the housing 210 can be measured through the optical fiber 10 to improve data accuracy. The optical fiber 10 is positioned relative to the large cell surface. The number and location of the grating temperature measurement points 11 can be reasonably set according to the thermal field distribution. The relatively large heat generation on the large cell surface indicates more accurate measurement.

[0027] In some embodiments, a groove or a fixed support may be disposed on the housing 210. The optical fiber 10 is embedded in the groove or disposed on a fixed support. As used herein, the groove or fixed support may be disposed inside or outside the housing 210. Correspondingly, the optical fiber 10 may be disposed in a groove or on a fixed support located inside the housing 210, or the optical fiber 10 may be disposed in a groove or on a fixed support located on the surface of the housing 210 facing the bare cell 220. The optical fiber 10 may also be disposed in a groove or on a fixed support on the surface of the housing 210 opposite the bare cell 220. In other words, the optical fiber 10 is disposed on the outside of the housing 210. The specific location of the optical fiber 10 is not limited herein. In some other embodiments, the optical fiber 10 may be disposed on the side of the housing 210 facing the bare cell 220 or on the bare cell 220. In this case, the optical fiber 10 may be fixed to the housing 210 or the bare cell 220 using a thermally conductive structural adhesive.

[0028] It should be noted that the optical fiber 10 may also have a relatively high resistance to electrolytes. Therefore, the optical fiber may be disposed within the housing 210, allowing for more accurate detection of the temperature field. In addition, the optical fiber 10 has a small geometric size and high scalability, allowing its position to be reasonably set according to deployment requirements.

[0029] 2 and 3, in some embodiments of the present disclosure, the input and output terminals of the optical fiber 10 are located at the same end of the cell body 200 and extend from the cell body 200 for connection to the computer 20. In this manner, wires may extend from the same side of the input and output terminals to shorten the overall length of the optical fiber 10, which can further reduce costs.

[0030] In some embodiments, the optical fiber 10 is disposed on at least one end face in the length direction or width direction of the cell body 200 and extends along the width direction or length direction. In addition, the optical fiber 10 is bent. The protrusions of the optical fiber 10 along the height direction shown in FIG. 1 at least partially overlap. Specifically, the optical fiber 10 is disposed on at least one end face in the length direction of the cell body 200, the optical fiber 10 extends along the length direction, and the optical fiber 10 is bent, and / or the optical fiber 10 is disposed on at least one end face in the width direction of the cell body 200, the optical fiber 10 extends along the width direction, and the optical fiber 10 is bent. This arrangement of the wire can reduce the number of bends of the optical fiber 10 while still satisfying the condition that the optical fiber 10 covers the large cell surface of the bare cell 220, thereby improving measurement accuracy and operational stability and extending the service life of the temperature measurement assembly 100 composed of the optical fiber 10. This reduces the conductivity loss of the optical fiber 10 and reduces the possibility of breakage of the extension wire of the optical fiber 10.

[0031] 2 and 3, the surface defined by the optical fiber 10 in the length and height directions of the cell body 200 is arranged in an arcuate shape. In other words, the optical fiber 10 is arranged at the end of the cell body 200 along the length direction shown in FIG. 1, extends to the other end of the cell body 200, and then bent once along the height direction shown in FIG. 1. After being bent, the optical fiber 10 extends continuously along the length direction shown in FIG. 1 from the other end of the cell body 200 to the end of the cell body 200, and then bent again along the height direction shown in FIG. 1. The above process may be repeated multiple times to allow the optical fiber 10 to extend multiple times along the length direction and bend multiple times along the height direction, so that the protrusions of the optical fiber 10 in the height direction at least partially overlap and are arranged in a "bow" shape at the end portion of the cell body 200. In this way, more grating temperature measurement points 11 are arranged along the width or length of the cell body 200, thereby improving the accuracy and effectiveness of the temperature measurement. The grid temperature measurement points 11 can be arranged reasonably for the thermal field distribution, which is not limited in this specification.

[0032] In some embodiments, the lattice temperature measurement points 11 are arranged in an array that may be arranged in longitudinal rows and vertical columns as shown in FIG. 1 so that multiple lattice temperature measurement points 11 are distributed at intervals within multiple temperature measurement areas to improve the temperature measurement accuracy of each temperature measurement area and to help obtain the numerical values ​​and locations of the highest and lowest temperature points.

[0033] In some embodiments, the optical fiber 10 includes a first section 12 and a second section 13. The first sections 12 are constructed as multiple first sections extending in a first direction and spaced apart in a second direction. Each first section 12 is provided with the same number of grating temperature measurement points 11. The second sections 13 are disposed at the ends of two adjacent first sections 12 on the same side, connecting the two first sections 12. The first direction is the length direction or width direction. The second direction is the height direction. In other words, the first sections 12 extend in the length direction shown in FIG. 1, with the multiple first sections 12 distributed over the large cell surface of the bare cell 220, and the protrusions of the multiple first sections 12 along the height direction of the cell body 200 overlapping each other. Each first section 12 is provided with multiple lattice temperature measurement points 11, and the number of lattice temperature measurement points 11 in each first section 12 is the same to achieve temperature detection at multiple heights on the large cell surface of the bare cell 220. In addition, the second section 13 extends in the height direction shown in FIG. 1 so that the first sections 12 are connected consecutively and neatly, facilitating the arrangement of the optical fiber 10, and is connected to the ends of two adjacent first sections 12 on the same side. In this manner, the optical fiber 10 is entirely arranged at one end of the cell body 200 along the length direction shown in FIG. 1 and extends to the other end of the cell body 200, and then the optical fiber 10 is bent once along the height direction shown in FIG. 1. After being bent, the optical fiber 10 extends continuously from the other end of the cell body 200 to the end of the cell body 200 along the length direction shown in FIG. 1, and then is bent again in the height direction shown in FIG. 1. The above process may be repeated multiple times so that more grid temperature measurement points 11 are positioned across the width or length of the cell body 200, thereby improving the accuracy and effectiveness of the temperature measurement.

[0034] In some embodiments, the distance between two adjacent lattice temperature measurement points 11 in the same first section 12 is the same so that the lattice temperature measurement points 11 are uniformly distributed on the first section 12 and the temperature measurement is more accurate and precise.

[0035] In some embodiments, the distance between two grating temperature measurement points 11 located in two adjacent first sections 12 and exactly opposite each other in the second direction is the same. In other words, the distance between each two adjacent first sections 12 is equal, and the number of grating temperature measurement points 11 in the same first section 12 is the same as the distance between two adjacent grating temperature measurement points 11. Therefore, the grating temperature measurement points 11 located in two adjacent first sections 12 are arranged exactly opposite each other in the second direction. In this case, the distances between the multiple grating temperature measurement points 11 in the two adjacent first sections 12 are all the same to allow the grating temperature measurement points 11 to be uniformly distributed on the optical fiber 10, thereby improving the accuracy and effectiveness of the temperature measurement.

[0036] As shown in FIG. 1, a battery module according to an embodiment of the second aspect of the present disclosure includes a plurality of cells 2000 in the above embodiment.

[0037] The optical fiber 10 can be arranged on each cell body 200 of the cells 2000. A plurality of relatively short optical fibers 10 can be connected to the computer 20, or a relatively long optical fiber 10 can be employed and arranged continuously on the plurality of cells 2000 to achieve an arrangement in which a single optical fiber 10 is shared by a plurality of cells 2000. Furthermore, the same optical fiber 10 can be arranged on all cell bodies 200 of the entire battery module to later detect the temperature field of the entire battery module and trigger different thermal management policies, thereby achieving location and numerical confirmation of the highest and lowest temperature points of a single cell body 200 and the entire battery pack 1000.

[0038] In the battery module according to the embodiment of the present disclosure, the above-mentioned cell 2000 is used to achieve a large amount of data detection at the location where temperature measurement is required, and the measurement data is free from data drift caused by electromagnetic interference and has high accuracy. In addition, the temperature field of the entire battery module may be measured to monitor the entire battery module in real time, which facilitates the triggering of auxiliary thermal management strategies and improves the operational stability and usage safety of the battery module.

[0039] In some embodiments, the battery module further includes a bus bar, with the output and input terminals of the optical fiber 10 integrated into the bus bar.

[0040] Illustratively, one optical fiber 10 is placed for each cell 2000, and then the entire optical fiber 10 can be pulled out from the side or integrated with a bus bar to extend the wire through gaps in or existing structures, thereby minimizing changes to the overall structure of the battery module and effectively reducing costs.

[0041] The battery pack 1000 according to an embodiment of the third aspect of the present disclosure employs the battery module in the above embodiment and has the same technical effects as the battery module, and the details will not be repeated here.

[0042] In the description herein, when a description is given with reference to terms such as "one embodiment," "some embodiments," "exemplary embodiment," "one example," "specific example," and "some examples," it means that the particular feature, structure, material, or characteristic described with reference to an embodiment or example is included in at least one embodiment or example of the present disclosure. As used herein, exemplary references to such terms do not necessarily refer to the same embodiment or example. In addition, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0043] While embodiments of the present disclosure have been illustrated and described, it will be apparent to those skilled in the art that various changes, modifications, substitutions, and variations can be made to the embodiments without departing from the principles and spirit of the present disclosure, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A cell (2000), A cell body (200) and an optical fiber (10), wherein a plurality of grating temperature measurement points (11) are formed on the optical fiber (10), and the optical fiber (10) is disposed on the cell body (200). A cell (2000) comprising:

2. The cell (2000) of claim 1, wherein the cell body (200) comprises a housing (210) and a bare cell (220) disposed on the housing (210), and the optical fiber (10) is disposed on the housing (210) or the bare cell (220).

3. the optical fiber (10) is disposed on the side of the housing (210) facing the bare cell (220), the side being the large cell surface of the housing; and / or The optical fiber (10) is disposed on a side of the housing (210) opposite the bare cell (220), the side being the large cell surface of the housing. A cell (2000) according to claim 1 or 2.

4. The cell (2000) according to claim 2 or 3, wherein the outer surface of the bare cell (220) has a large cell surface, and the optical fiber (10) is disposed on the large cell surface.

5. The cell (2000) according to any one of claims 2 to 4, wherein a groove is provided on the housing (210), and the optical fiber (10) is embedded in the groove.

6. A cell (2000) according to any one of claims 1 to 5, wherein the input and output terminals of the optical fiber (10) are at the same end of the cell body (200) and extend from the cell body (200).

7. The optical fiber (10) is disposed on at least one end face of the cell body (200) in the longitudinal direction, the optical fiber (10) extends along the longitudinal direction, the optical fiber (10) is bent, and / or The optical fiber (10) is arranged on at least one end surface in the width direction of the cell body (200), the optical fiber (10) extends along the width direction, and the optical fiber (10) is bent. A cell (2000) according to any one of claims 1 to 6.

8. The cell (2000) according to any one of claims 1 to 7, wherein the optical fibers (10) are arranged in an arcuate shape on a surface defined by the length and height directions of the cell body (200).

9. The cell (2000) according to any one of claims 1 to 8, wherein the grid temperature measurement points (11) are arranged in an array.

10. The optical fiber (10) a first section (12) extending in a first direction and constructed as a plurality of first sections spaced apart in a second direction, each of the first sections (12) being provided with the same number of grating temperature measurement points (11); a second section (13) arranged at the ends of two adjacent first sections (12) on the same side, connecting the two first sections (12), the first direction being a length direction or width direction, and the second direction being a height direction; The cell (2000) of claim 9, comprising:

11. The cell (2000) according to claim 10, wherein the distance between two adjacent grid temperature measurement points (11) in the same first section is the same.

12. 11. The cell (2000) according to claim 10, wherein the distance between two lattice temperature measurement points (11) located in two adjacent first sections and exactly opposite each other in the second direction is the same.

13. A battery module comprising a plurality of cells (2000) according to any one of claims 1 to 12.

14. 14. The battery module of claim 13, further comprising a bus bar, wherein the output and input terminals of the optical fiber (10) are integrated with the bus bar.

15. A battery pack (1000) comprising a battery module according to claim 13 or 14.

16. 16. The battery pack (1000) of claim 15, further comprising a computer (20), said computer (20) adapted to connect to the output terminal and the input terminal of said optical fiber (10).

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