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 The present disclosure claims priority to Chinese Patent Application No. 202222451774.9, filed on September 15, 2022, entitled "Battery Cell, Battery Module, and Battery Pack". The entire content of the above application is incorporated herein by reference.

[0002] Technical Field The present disclosure relates to the technical field of cells, and more specifically, to a cell, a battery module, and a battery pack. [Background Art]

[0003] In the related art, the temperature of a battery is mainly detected through a plurality of thermistors. A relatively small number of data points are provided for temperature collection, these have a single arrangement form, and can only be arranged at the end portions of the cell. The collected data is single, and it is difficult to collect the maximum temperature and the minimum temperature inside the cell. In addition, data collection is susceptible to the influence of electromagnetic interference, which brings about data drift, reduced test accuracy, and great difficulty in arrangement. [Summary of the Invention] [Means for Solving the Problems]

[0004] The present disclosure is intended 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. In order to perform temperature measurement on the cell with high temperature measurement accuracy, low environmental impact, reasonable space occupation, and high arrangement convenience, lattice temperature measurement points are arranged on a cell body.

[0005] The present disclosure further provides a battery module comprising the above cell.

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

[0007] The cell according to this disclosure includes a cell body and an optical fiber. Multiple grid temperature measurement points are formed on the optical fiber. The optical fiber is placed on the cell body.

[0008] In the cell according to this disclosure, grid temperature measurement points are placed on the cell body to perform temperature measurements on the cell. In this way, on the one hand, the number and placement of grid temperature measurement points are more rational, the data sample is richer, the cell temperature measurement is more accurate, and preparations for subsequent cell temperature control are made. On the other hand, optical fibers have a small geometric size, fewer constraints due to physical structure, are easy to place, can be placed without changing the cell structure, and are not affected by electromagnetic interference. Thus, the acquisition accuracy is high and the data is accurate.

[0009] The battery module described herein includes the aforementioned multiple cells.

[0010] The battery pack described herein includes the battery module described above.

[0011] Some of the additional aspects and benefits of this disclosure are provided in the following description, which will become apparent from the following description or through the implementation of this disclosure. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram of a battery pack according to one embodiment of the present disclosure. [Figure 2] This is a schematic diagram of the fitting between the temperature measuring assembly and the cell according to the first embodiment of the present disclosure. [Figure 3] This is a schematic diagram of the fitting between the temperature measuring assembly and the cell according to a second embodiment of the present disclosure. [Explanation of Symbols]

[0013] Battery pack 1000; Cells 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 [Modes for carrying out the invention]

[0014] Embodiments of this disclosure are described in detail below. Examples of embodiments are shown in the accompanying drawings. The same or similar elements, or elements having the same or similar function, are denoted by the same or similar reference numerals throughout this description. The embodiments described below with reference to the accompanying drawings are illustrative and used solely to illustrate this disclosure and should not be construed as limitations on this disclosure.

[0015] Hereinafter, the cell 2000, battery module, and battery pack 1000 according to embodiments of this disclosure will be described with reference to Figures 1 to 3.

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

[0017] Multiple grid temperature measurement points 11 are formed on the optical fiber 10.

[0018] In this disclosure, the optical fiber 10 is placed on the cell body 200 and has a grid pre-etched on it as a grid temperature measurement point 11. The optical fiber 10 can be signal-connected to a computer 20 located 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 placed 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 to realize temperature measurement of the cell body 200. It should be understood that the battery pack 1000 has multiple cells 2000. The battery pack 1000 further has a thermal management system for performing thermal management for the cells 2000. The computer 20 is located outside the cell 2000 and is built as part of the thermal management system.

[0019] It should be noted that a grating is an optical device composed of numerous parallel slits with regularly changing intervals, for example, an equidistant grating of parallel slits of the same spacing width. The above-mentioned numerous parallel slits with regularly changing intervals are engraved on the fiber core of the optical fiber 10 through the photosensitivity of the material of the optical fiber 10 so that a grating is formed. However, the flexible use of the grating lies in its ability to achieve multi-point detection. Theoretically, countless gratings of different wavelengths can be engraved within a single optical fiber 10 to achieve dispersed monitoring of the same physical parameter or multiple physical parameters. An optical fiber 10 with multiple gratings engraved on it is formed as an optical fiber grating string. By precisely positioning the distance between two reflection points, optical wave signals that satisfy the conditions are reflected by the grating, and signals with different wavelengths are substantially not reflected. Through connection of the grating to a demodulator, the optical wave wavelengths of independent radiated waves emitted by a signal source can be measured. When the grating is affected by temperature changes or stress field changes, the grating pitch changes, and the wavelength of the reflected waves also changes accordingly, radiating different wavelengths and achieving the temperature measurement function of the grating temperature measurement point 11 based on different wavelengths.

[0020] Based on the above, the grid temperature measurement points 11 are arranged in regions with drastic temperature changes and regions where temperature needs to be collected according to the size and heat field distribution of the cell body 200 (for example, as shown in Figure 2 and Figure 3, the plurality of grid temperature measurement points 11 are arranged at equal intervals in the height direction and length direction of the cell body 200). In addition, the optical fiber 10 has a small geometric size, with a diameter of only one hundred or hundreds of microns. In this way, not only the physical constraints caused by the laminated structure of the bus bars and the cell body 200 can be overcome, but also the constraints are reduced, thereby realizing various forms of arrangement and reasonable arrangement of the grid temperature measurement points 11. Since a larger number of measurement points indicates richer collected data, the maximum temperature and minimum temperature of the cell body 200 can be collected, and the positions of the maximum temperature point and the minimum temperature point can be determined. More abundant samples indicates more accurate temperature measurement of the cell 2000, which further facilitates the subsequent temperature control of the cell body 200. In addition, temperature measurement via the optical fiber 10 is not affected by electromagnetic interference, so the data is more accurate and the collection accuracy is high.

[0021] In the cell 2000 according to the embodiment of the present disclosure, the grid temperature measurement points 11 are arranged on the cell body 200 to perform temperature measurement on the cell body 200. In this way, on one hand, the number and arrangement positions of the grid temperature measurement points 11 can be more reasonable, and the data samples can 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 constrained by the physical structure, has low arrangement difficulty, can be arranged without changing the structure of the cell body 200, and is not affected by electromagnetic interference. Thus, the collection accuracy is high and the data is accurate.

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

[0023] The cell body 200 and the optical fiber 10 may be fixed by a plurality of methods, for example, using a thermally conductive structural adhesive, or the optical fiber 10 is fixed to the bare cell 220 or the housing 210 through arrangement such as a fixing support, a fixing groove, or the like.

[0024] For illustration, as shown in FIG. 3, the optical fiber 10 is arranged on a side surface of the housing 210 facing the bare cell 220, and / or the optical fiber 10 is arranged on a side surface of the housing 210 opposite to the bare cell 220. Specifically, the side surface may be collectively defined by the height direction and the length direction shown in FIG. 1.

[0025] In some embodiments, the housing 210 has a large cell surface facing or opposite to the bare cell 220. The optical fiber 10 is arranged on the large cell surface. Alternatively, an outer surface of the bare cell 220 may have the large cell surface, and the optical fiber 10 may be arranged 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 has a plurality of surfaces, and 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, in order to directly or indirectly achieve temperature measurement of the cell body 200 and improve data accuracy, the temperature of the bare cell 220 or the housing 210 can be measured through the optical fiber 10. The optical fiber 10 is arranged relative to the large cell surface. The quantity and position of the grating temperature measurement points 11 can be reasonably set according to the heat field distribution. A relatively large heat generation amount on the large cell surface indicates more accurate measurement.

[0027] In some embodiments, grooves or fixing supports can be located on the housing 210. The optical fiber 10 is embedded in the groove or positioned on the fixing support. In this specification, the grooves or fixing supports can be located inside or outside the housing 210. Correspondingly, the optical fiber 10 may be located in a groove or on a fixing support located inside the housing 210, or it may be located in a groove or on a fixing support located on the surface of the housing 210 facing the bare cell 220. The optical fiber 10 may be further positioned in a groove or on a fixing support on the surface of the housing 210 opposite the bare cell 220. In other words, the optical fiber 10 is located outside the housing 210. The specific position of the optical fiber 10 is not limited herein. In some other embodiments, the optical fiber 10 may be located 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 can be fixed to the housing 210 or the bare cell 220 using a thermally conductive structural adhesive.

[0028] It should also be noted that the optical fiber 10 may have relatively high resistance to electrolytes. Therefore, the optical fiber may be placed inside 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 rationally determined according to placement requirements.

[0029] As shown in Figures 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 way, the wire may extend from the same side of the input and output terminals to shorten the overall length of the optical fiber 10, thereby further reducing costs.

[0030] In some embodiments, the optical fiber 10 is positioned at least one end face of the cell body 200 in the longitudinal or widthwise direction and extends along the widthwise or longitudinal direction. In addition, the optical fiber 10 is bent. The projection of the optical fiber 10 along the height direction shown in Figure 1 overlaps at least partially. Specifically, the optical fiber 10 is positioned at least one end face of the cell body 200 in the longitudinal direction, the optical fiber 10 extends along the longitudinal direction and the optical fiber 10 is bent, and / or the optical fiber 10 is positioned at least one end face of the cell body 200 in the widthwise direction, the optical fiber 10 extends along the widthwise direction and the optical fiber 10 is bent. Through such arrangement of the wire, the number of bends of the optical fiber 10 can be reduced while satisfying the condition that the optical fiber 10 covers the large cell surface of the bare cell 220, thereby reducing the conductivity loss of the optical fiber 10 and reducing the possibility of breakage of the extension wire of the optical fiber 10 in order to improve measurement accuracy and operational stability and extend the service life of the temperature measurement assembly 100 composed of the optical fiber 10.

[0031] In this specification, as shown in Figures 2 and 3, the surface defined in the longitudinal and vertical directions of the cell body 200 by the optical fiber 10 is arranged in an arc shape. In other words, the optical fiber 10 is positioned at one end of the cell body 200 along the longitudinal direction shown in Figure 1, extends to the other end of the cell body 200, is then bent once along the vertical direction shown in Figure 1, and after the bend, extends continuously along the longitudinal direction shown in Figure 1 from the other end of the cell body 200 to the end of the cell body 200, and is then bent again in the vertical direction shown in Figure 1. The above process may be repeated multiple times to allow the optical fiber 10 to extend in the longitudinal direction and bend in the vertical direction multiple times so that the projections of the optical fiber 10 in the vertical direction overlap at least partially and are arranged in an "arc" shape at the terminal portion of the cell body 200. In this way, more grid temperature measurement points 11 are positioned in the widthwise or longitudinal direction of the cell body 200, thereby improving the accuracy and effectiveness of temperature measurement. The grid temperature measurement points 11 can be reasonably positioned for the heat field distribution, but this is not limited to the foregoing.

[0032] In some embodiments, the grid temperature measurement points 11 are arranged in an array, which may be arranged in rows in the length direction and columns in the height direction as shown in Figure 1, so that multiple grid temperature measurement points 11 are distributed at intervals within multiple temperature measurement areas, in order 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 section 12 is constructed as a plurality of first sections extending in a first direction and spaced apart in a second direction. Each of the first sections 12 is provided with the same number of grid temperature measurement points 11. The second section 13 is located at the ends of two adjacent first sections 12 on the same side and connects the two first sections 12. The first direction is the length direction or the width direction. The second direction is the height direction. In other words, the first section 12 extends in the length direction as shown in Figure 1, with a plurality of first sections 12 distributed over the large cell surface of the bare cell 220, and the projections of the plurality of first sections 12 along the height direction of the cell body 200 overlapping. Each first section 12 is provided with multiple grid temperature measurement points 11, and the number of grid temperature measurement points 11 in each first section 12 is the same in order 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 Figure 1 so that the first sections 12 are connected in a continuous and orderly manner, in order to facilitate the placement of the optical fiber 10, and is connected to the ends of two adjacent first sections 12 on the same side. In this way, the optical fiber 10 is positioned as a whole at one end of the cell body 200 along the length direction shown in Figure 1, extends to the other end of the cell body 200, then the optical fiber 10 is bent once along the height direction shown in Figure 1, and after bending, the optical fiber 10 extends continuously along the length direction shown in Figure 1 from the other end of the cell body 200 to the end of the cell body 200, and then bent again in the height direction shown in Figure 1. The above process may be repeated multiple times so that more grid temperature measurement points 11 are positioned in the widthwise or lengthwise direction of the cell body 200, thereby improving the accuracy and effectiveness of the temperature measurement.

[0034] In some embodiments, the distance between two adjacent grid temperature measurement points 11 in the same first section 12 is the same so that the grid 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 grid temperature measurement points 11 located in two adjacent first sections 12 and precisely facing each other in a second direction is the same. In other words, the distance between two adjacent first sections 12 is equal, and the number of grid temperature measurement points 11 in the same first section 12 is the same as the distance between two adjacent grid temperature measurement points 11. Thus, the grid temperature measurement points 11 located in two adjacent first sections 12 are positioned precisely facing each other in a second direction. In this case, the distances between the multiple grid temperature measurement points 11 in the two adjacent first sections 12 are all the same in order to allow the grid temperature measurement points 11 to be uniformly distributed on the optical fiber 10, thereby improving the accuracy and effectiveness of temperature measurement.

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

[0037] The optical fiber 10 described above can be placed on each cell body 200 of the cell 2000. Multiple relatively short optical fibers 10 may be connected to the computer 20, or a relatively long optical fiber 10 may be used and placed consecutively on multiple cells 2000 to achieve an arrangement where multiple cells 2000 share a single optical fiber 10. Furthermore, the same optical fiber 10 may be placed 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 also achieving location and numerical verification 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 embodiments of this disclosure, a large amount of data can be detected at locations where temperature measurement is required, and the cell 2000 described above is used so that the measured data does not experience data drift caused by electromagnetic interference and is highly accurate. In addition, the temperature field of the entire battery module may be measured in order to monitor the entire battery module in real time, thereby facilitating the triggering of auxiliary thermal management strategies and improving the operational stability and safety of use of the battery module.

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

[0040] For example, one optical fiber 10 may be placed for every 2000 cells and then pulled out as a whole from the side or integrated with a busbar, extending the wire through gaps or existing structures in the existing structure, thereby minimizing changes to the overall structure of the battery module and effectively reducing costs.

[0041] In a battery pack 1000 according to one embodiment of a third aspect of this disclosure, the battery module in the above embodiment is employed and has the same technical effects as the above battery module. Details are not repeated herein.

[0042] In this specification, descriptions given with reference to terms such as “one embodiment,” “several embodiments,” “exemplary embodiment,” “one example,” “specific example,” and “several examples” mean that certain features, structures, materials, or properties described with reference to an embodiment or example are included in at least one embodiment or example of this disclosure. In this specification, the exemplary descriptions of the above terms do not necessarily refer to the same embodiment or example. In addition, certain features, structures, materials, or properties described may be combined in an appropriate manner in any one or more embodiments or examples.

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

Claims

1. Cell (2000), A cell body (200) and an optical fiber (10), wherein a plurality of lattice temperature measurement points (11) are formed on the optical fiber (10), and the optical fiber (10) is arranged on the cell body (200). Equipped with, The cell body (200) comprises a housing (210) and a bare cell (220) disposed in the housing (210). The optical fiber (10) is positioned on the side of the housing (210) facing the bare cell (220), and / or The optical fiber (10) is positioned on the side of the housing (210) opposite to the bare cell (220). Cell (2000).

2. The cell (2000) according to claim 1, wherein a groove is provided on the housing (210) and the optical fiber (10) is embedded in the groove.

3. The cell (2000) according to claim 1, wherein the input terminal and output terminal of the optical fiber (10) are located at the same end of the cell body (200) and extend from the cell body (200).

4. The optical fiber (10) is located at least one end face in the longitudinal direction of the cell body (200), 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 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. The cell (2000) according to claim 1.

5. The cell (2000) according to claim 1, wherein the optical fiber (10) is arranged in an arc shape on a surface defined by the length and height directions of the cell body (200).

6. The cell (2000) according to claim 1, wherein the grid temperature measurement points (11) are arranged in an array.

7. The optical fiber (10) is A first section (12), the first section (12) is constructed as a plurality of first sections extending in a first direction and spaced apart in a second direction, and each of the first sections (12) is provided with the same number of grid temperature measurement points (11), A second section (13), the second section (13) is located at the ends of two adjacent first sections (12) on the same side, connecting the two first sections (12), the first direction being the length direction or width direction, and the second direction being the height direction, A cell (2000) according to claim 6, comprising:

8. The cell (2000) according to claim 7, wherein the distance between two adjacent grid temperature measurement points (11) in the same first interval is the same.

9. The cell (2000) according to claim 7, wherein the distance between two grid temperature measurement points (11) located in two adjacent first sections and precisely facing each other in the second direction is the same.

10. A battery module comprising a plurality of cells (2000) as described in claim 1.

11. A battery pack (1000) comprising the battery module described in claim 10.

12. The battery pack (1000) according to claim 11, further comprising a computer (20), wherein the computer (20) is connected to the output terminal and input terminal of the optical fiber (10).

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