Electrode assembly, battery cell, and battery
Patent Information
- Application Number
- CN202522209436.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-17
- Publication Date
- 2026-11-03
- Estimated Expiration
- 2035-10-17
AI Technical Summary
In existing technologies, lithium plating at the negative electrode is a serious problem during battery charging, leading to performance degradation and safety hazards. Furthermore, existing testing methods require disassembling the battery cell, which is complex and affects accuracy.
Design an electrode assembly comprising a negative electrode, a separator, and an optical fiber bundle. The detection part of the optical fiber bundle is disposed in the mounting groove of the separator and is connected to a monitoring module through a connection part to monitor the lithium plating information of the negative electrode in real time. It is also isolated from the electrolyte by a protective layer to avoid corrosion.
This technology enables real-time monitoring of the lithium plating state of the negative electrode without disassembling the electrode assembly, improving the safety and monitoring accuracy during battery use and extending the service life of the detection and connection parts.
Smart Images
Figure CN224934778U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of energy storage technology, and in particular to an electrode assembly, a cell, and a battery. Background Technology
[0002] Batteries, as key devices for modern energy storage and conversion, play a vital role in various electronic devices, electric vehicles, and energy storage systems. However, charging is an unavoidable and extremely important part of battery use. But during battery charging, there exists a serious hidden danger that affects battery performance and safety—lithium plating at the negative electrode.
[0003] Lithium plating at the negative electrode refers to the excessive deposition of lithium ions on the surface of the negative electrode during charging, forming metallic lithium. This phenomenon is particularly pronounced under certain conditions, especially in low-temperature environments and fast-charging scenarios, where the risk of lithium plating in batteries increases dramatically. Low temperatures slow down the diffusion rate of lithium ions, causing the deposition rate on the negative electrode surface to exceed the rate at which they embed into the negative electrode material, thus making lithium plating more likely. In fast-charging scenarios, the high current causes lithium ions to rush to the negative electrode rapidly. If the embedding capacity of the negative electrode material cannot keep up, lithium plating will also occur.
[0004] The negative impacts of lithium plating on the negative electrode of a battery are multifaceted. First, it severely degrades battery performance. The deposited lithium metal can no longer participate in normal electrochemical reactions and increases the battery's internal resistance, leading to reduced charge and discharge efficiency, accelerated capacity decay, and ultimately, a shortened battery lifespan. More seriously, the dendritic lithium formed by lithium plating poses a significant danger. These dendritic lithium metals act like sharp needles, and as the plating progresses, they may gradually grow and puncture the battery's internal separator. As a crucial insulating layer between the positive and negative electrodes, puncture of the separator will trigger an internal short circuit. An internal short circuit causes a sharp increase in internal current, generating a large amount of heat, which can potentially lead to serious safety accidents such as battery fires and explosions, posing a significant threat to people's lives and property.
[0005] The testing methods in related technologies often require disassembling the battery cells, which is not only complex and time-consuming, but may also cause further damage to the cells during disassembly, affecting the accuracy of the test results. Furthermore, disassembling the cells makes it impossible to monitor the battery in real time during use. Utility Model Content
[0006] This application provides an electrode assembly that can obtain lithium plating information of the negative electrode without disassembly, thereby at least partially solving the above-mentioned technical problems.
[0007] To achieve the above objectives, according to a first aspect of this application, an electrode assembly is provided, comprising: Negative electrode plate; A separator, wherein the negative electrode sheet is disposed on one side of the separator, and a mounting groove is provided on one side of the separator; and, The fiber bundle has a connected detection part and a connecting part. The detection part is disposed in the mounting groove and is used to detect the lithium plating information of the negative electrode. The connecting part is used to connect to a monitoring module so that the lithium plating information can be transmitted to the monitoring module.
[0008] Optionally, the electrode assembly further includes a protective layer disposed in the mounting groove and covering the detection portion to isolate the detection portion from the electrolyte located between the negative electrode and the diaphragm.
[0009] Electrolytes are corrosive, but by covering the detector with a protective layer, the detector can be isolated from the electrolyte located between the negative electrode and the diaphragm, preventing the detector from being corroded by the electrolyte and thus greatly extending the service life of the detector.
[0010] Optionally, the ratio of the average depth of the mounting groove to the average thickness of the diaphragm is between 1 / 3 and 1 / 2; this average depth of the mounting groove satisfies the installation requirements of the detection unit and the protective layer, while avoiding affecting the structural strength of the diaphragm due to excessive depth; and / or, The ratio of the average thickness of the detection section to the average depth of the mounting groove is between 1 / 2 and 2 / 3; this average thickness setting of the detection section satisfies the requirement for detecting lithium plating information of the negative electrode sheet while preventing it from protruding from the separator and squeezing the negative electrode sheet; and / or, The ratio of the average thickness of the protective layer to the average depth of the mounting groove is between 1 / 3 and 1 / 2. This protective layer can effectively separate the probe from the electrolyte and prevent it from protruding from the diaphragm and squeezing the negative electrode sheet.
[0011] Optionally, the protective layer includes adhesive, and the probe can be fixed in the mounting groove by the adhesive; The adhesive includes at least one of UV adhesive, ion-conductive adhesive, and fluorinated adhesive.
[0012] By installing the probe in the mounting groove and then injecting glue into the mounting groove to form a protective layer covering the probe, not only can the probe be isolated from the electrolyte located between the negative electrode and the separator, but the probe can also be fixed in the mounting groove to ensure the stability of the connection between the probe and the mounting groove.
[0013] Optionally, an overflow space is formed between the end of the probe away from the connector and the end of the mounting groove, and the overflow space is at least able to receive a portion of the glue overflowing from the probe.
[0014] When glue is injected into the mounting groove to form a protective layer covering the detector, excess glue can flow into the overflow space, thereby preventing the glue from overflowing into the mounting groove and solidifying on the diaphragm to form a protrusion.
[0015] Optionally, the distance between the end of the probe furthest from the connector and the end of the mounting groove is between 2mm and 3mm. This distance ensures effective containment of any excess adhesive spilled at the probe while avoiding affecting the length of the probe.
[0016] Optionally, the electrode assembly further includes a positive electrode plate, with the negative electrode plate and the positive electrode plate respectively disposed on opposite sides of the separator. Separating the positive and negative electrode plates by the separator prevents direct contact between them and avoids short circuits.
[0017] Optionally, both the diaphragm and the negative electrode are wound together, and the mounting groove is arranged circumferentially along the diaphragm so that the probe is wound between the diaphragm and the negative electrode.
[0018] The separator and the negative electrode are wound together to form a multi-layered spiral structure. The detector is placed in the mounting groove of the separator and wound together with the separator. Therefore, the detector forms a spiral detection structure between the separator and the negative electrode. When the detection light is transmitted along the axial direction of the detector, it can be emitted from the side perpendicular to its axial direction (optical fiber lateral coupling) to detect the lithium plating information of the negative electrode along the radial direction of the spiral negative electrode, which can more comprehensively detect the lithium plating information on the spiral negative electrode.
[0019] Optionally, the connecting part has a relaxation section, which is connected to the detection part. The relaxation section is bent to release the stress when the detection part is wound, so as to avoid excessive stress in the detection part, which may lead to a decrease in the performance of the optical fiber ring or even damage to the optical fiber.
[0020] Optionally, the electrode assembly includes an isolation component disposed outside the connection portion, the isolation component being used to isolate the connection portion from the electrolyte inside the battery cell.
[0021] By using an isolation component covering the connection part, the isolation component can be isolated from the electrolyte inside the cell, preventing the connection part from being corroded by the electrolyte, thereby greatly extending the service life of the connection part.
[0022] Optionally, the isolation component includes a flexible sealing layer, a curing layer, and a metal sleeve, which are sequentially fitted over the connecting portion to encapsulate it. In this three-layer encapsulation structure, the flexible sealing layer provides stress buffering and primary sealing, the curing layer provides structural support and an absolute barrier, and the metal sleeve provides mechanical protection and resistance to compression. Together, they form a protective system that combines flexibility, rigidity, chemical inertness, and mechanical strength, ensuring signal integrity and reliability during the use of the connecting portion.
[0023] Optionally, the flexible sealing layer includes a fluororubber ring, which can buffer stress, prevent the optical fiber from being crushed or broken, and provide an initial seal; and / or, The cured layer includes nano-ceramic epoxy adhesive, which forms a hard and dense chemical barrier outside the joint, completely preventing the penetration of corrosive electrolyte components such as hydrofluoric acid (HF) and protecting the joint from corrosion; and / or, The metal sleeve, including a titanium alloy sleeve, provides the strongest mechanical protection, preventing the connection from being punctured by electrode burrs or crushed by external forces during assembly and use.
[0024] According to a second aspect of this application, a battery cell is provided, including the electrode assembly described in the first aspect above.
[0025] According to a third aspect of this application, a battery is provided, comprising: The battery cell as described in the second aspect above; and, A monitoring module is connected to the connection part of the battery cell.
[0026] In the electrode assembly of this application embodiment, the detection unit can monitor the lithium plating state of the negative electrode in real time and transmit relevant information to the monitoring module through the connection unit, thereby realizing continuous monitoring of lithium plating information, including whether lithium plating has occurred on the negative electrode and the specific degree of lithium plating. This monitoring process does not require disassembly of the electrode assembly, significantly improving the safety of the cells and batteries using this electrode assembly during use. In addition, since the detection unit is located in the mounting groove of the separator, its position is more stable, which helps to ensure higher reliability and accuracy when detecting lithium plating information of the negative electrode.
[0027] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0028] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.
[0029] Figure 1 This is a schematic diagram of the structure of the positive electrode, negative electrode and separator when they are wound up according to the exemplary embodiments of this disclosure.
[0030] Figure 2 This is a schematic diagram of the structure of the positive electrode, negative electrode and separator provided in the exemplary embodiments of this disclosure when unfolded.
[0031] Figure 3 This is a schematic diagram of the structure of the fiber bundle and diaphragm as provided in the exemplary embodiment of this disclosure.
[0032] Figure 4 This is a schematic diagram of the structure of the optical fiber bundle provided in an exemplary embodiment of this disclosure.
[0033] Figure 5 This is a cross-sectional view of the detector, diaphragm, and protective layer provided in an exemplary embodiment of this disclosure.
[0034] Figure 6 This is a cross-sectional view of the isolation component and connection portion provided in an exemplary embodiment of this disclosure.
[0035] Figure 7 This is a control block diagram of the monitoring module and fiber optic bundle provided in an exemplary embodiment of this disclosure.
[0036] Explanation of reference numerals in the attached figures: 1. Electrode assembly; 11. Positive electrode; 12. Negative electrode; 13. Separator; 131. Mounting groove; 132. Glue overflow space; 14. Fiber optic bundle; 141. Detector section; 142. Connector section; 1421. Relaxation section; 15. Protective layer; 16. Isolation assembly; 161. Flexible sealing layer; 162. Curing layer; 163. Metal sleeve; 2. Monitoring module. Detailed Implementation
[0037] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.
[0038] According to the first aspect of this application, in conjunction with Figure 1-3 An electrode assembly 1 is provided, comprising a negative electrode 12, a separator 13, and an optical fiber bundle 14. The negative electrode 12 is disposed on one side of the separator 13, and the separator 13 has a mounting groove 131 on the side facing the negative electrode 12. The optical fiber bundle 14 has a connected detection part 141 and a connecting part 142. The detection part 141 is disposed in the mounting groove 131 and is used to detect lithium plating information of the negative electrode 12. The connecting part 142 is used to connect to a monitoring module 2 so that the lithium plating information can be transmitted to the monitoring module 2.
[0039] When electrode assembly 1 is in operation, the detection unit 141 can monitor the lithium plating state of the negative electrode 12 in real time and transmit relevant information to the monitoring module 2 through the connection unit 142, thereby realizing continuous monitoring of lithium plating information such as whether lithium plating has occurred on the negative electrode 12 and the specific degree of lithium plating; and this monitoring process does not require disassembly of electrode assembly 1, which significantly improves the safety of cells and batteries using this electrode assembly 1 during use. In addition, since the detection unit 141 is located in the mounting groove 131 of the separator 13, its position is more stable, which helps to ensure higher reliability and accuracy when detecting lithium plating information of the negative electrode 12.
[0040] For example, when the negative electrode 12 is disposed on one side of the separator 13, the negative electrode 12 may be directly attached to the separator 13; the negative electrode 12 may be disposed with a gap between it and the separator 13; or a portion of the negative electrode 12 may be directly attached to a portion of the separator 13, while another portion of the negative electrode 12 may be disposed with a gap between it and another portion of the separator 13.
[0041] In some embodiments, combined with Figure 4 It is understood that the electrode assembly 1 also includes a protective layer 15, which is disposed in the mounting groove 131 and covers the detection part 141 to isolate the detection part 141 from the electrolyte located between the negative electrode 12 and the separator 13.
[0042] The electrolyte has a certain degree of corrosiveness. By providing a protective layer 15 covering the detection part 141, the detection part 141 can be isolated from the electrolyte located between the negative electrode plate 12 and the diaphragm 13, thus preventing the detection part 141 from being corroded by the electrolyte and greatly extending the service life of the detection part 141.
[0043] When the detection unit 141 monitors the negative electrode 12, the protective layer 15 allows the laser to penetrate. The laser emitted by the detection unit 141 can pass through the protective layer 15 and irradiate the surface of the negative electrode 12. The laser reflected from the surface of the negative electrode 12 can also pass through the protective layer 15 again and return to the detection unit 141, thereby realizing real-time monitoring of the lithium plating state of the negative electrode 12.
[0044] In some embodiments, the ratio of the average depth of the mounting groove 131 to the average thickness of the diaphragm 13 is between 1 / 3 and 1 / 2; the average depth of the mounting groove 131 is set to meet the installation requirements of the probe 141 and the protective layer 15, while avoiding the impact on the structural strength of the diaphragm 13 due to excessive depth; and / or, The ratio of the average thickness of the detection section 141 to the average depth of the mounting groove 131 is between 1 / 2 and 2 / 3; this average thickness setting of the detection section 141 satisfies the requirement for detecting lithium plating information of the negative electrode 12, while also preventing it from protruding from the separator 13 and squeezing the negative electrode 12; and / or, The ratio of the average thickness of the protective layer 15 to the average depth of the mounting groove 131 is between 1 / 3 and 1 / 2. The protective layer 15 can effectively separate the probe 141 from the electrolyte and prevent it from protruding from the diaphragm 13 and squeezing the negative electrode 12.
[0045] For example, the ratio of the average depth of the mounting groove 131 to the average thickness of the diaphragm 13 can be 1 / 3 or 1 / 2; it is understood that the ratio of the average depth of the mounting groove 131 to the average thickness of the diaphragm 13 can also be other values, and this embodiment is not limited thereto; and / or, The ratio of the average thickness of the detection section 141 to the average depth of the mounting groove 131 can be 1 / 2 or 2 / 3; it is understood that the ratio of the average thickness of the detection section 141 to the average depth of the mounting groove 131 can also be other values, and this embodiment does not impose any limitations on this; and / or, The ratio of the average thickness of the protective layer 15 to the average depth of the mounting groove 131 can be 1 / 3 or 1 / 2; it is understood that the ratio of the average thickness of the protective layer 15 to the average depth of the mounting groove 131 can also be other values, and this embodiment does not limit this.
[0046] In some embodiments, the protective layer 15 includes adhesive, and the probe 141 can be fixed in the mounting groove 131 by the adhesive; The adhesive includes at least one of UV adhesive, ion-conductive adhesive, and fluorinated adhesive.
[0047] By installing the probe 141 into the mounting groove 131 and then injecting glue into the mounting groove 131 to form a protective layer 15 covering the probe 141, not only can the probe 141 be isolated from the electrolyte located between the negative electrode 12 and the separator 13, but the probe 141 can also be fixed in the mounting groove 131 to ensure the connection stability between the probe 141 and the mounting groove 131.
[0048] For example, a mounting groove 131 is formed on the diaphragm 13 using a laser, the detection part 141 of the fiber bundle 14 is installed in the mounting groove 131, UV adhesive is applied in the mounting groove 131 and cured for 10 seconds to form a protective layer 15 covering the detection part 141.
[0049] In some embodiments, an overflow space 132 is formed between the end of the probe 141 away from the connector 142 and the end of the mounting groove 131, and the overflow space 132 is able to receive at least part of the glue overflowing from the probe 141.
[0050] When glue is injected into the mounting groove 131 to form a protective layer 15 covering the probe part 141, excess glue can flow into the overflow space 132, thereby preventing the glue from overflowing from the mounting groove 131 and solidifying on the diaphragm 13 to form a protrusion.
[0051] In some embodiments, the distance between the end of the probe 141 furthest from the connector 142 and the end of the mounting groove 131 is between 2mm and 3mm. This distance ensures effective adhesion of any excess adhesive spilled from the probe 141 while avoiding affecting the length of the probe 141.
[0052] For example, the distance between the end of the probe 141 away from the connector 142 and the end of the mounting groove 131 can be 2mm, 2.5mm, or 3mm; it is understood that the distance between the end of the probe 141 away from the connector 142 and the end of the mounting groove 131 can also be other values, and this embodiment does not limit it.
[0053] In some embodiments, the electrode assembly 1 further includes a positive electrode 11, and a negative electrode 12, which are respectively disposed on opposite sides of the separator 13. The separator 13 separates the positive electrode 11 and the negative electrode 12, preventing them from coming into direct contact and avoiding short circuits.
[0054] In some embodiments, combined with Figure 5 It can be seen that both the diaphragm 13 and the negative electrode 12 are wound together, and the mounting groove 131 is arranged around the diaphragm 13 so that the probe 141 is wound between the diaphragm 13 and the negative electrode 12.
[0055] The separator 13 and the negative electrode 12 are wound together to form a multi-layered spiral structure. The detector 141 is placed in the mounting groove 131 of the separator 13 and is wound together with the separator 13. Therefore, the detector 141 forms a spiral detection structure located between the separator 13 and the negative electrode 12. When the detection light is emitted from the side of the detector 141, it detects the lithium plating information of the negative electrode 12 along the radial direction of the spiral negative electrode 12, which can more comprehensively detect the lithium plating information on the spiral negative electrode 12.
[0056] For example, the positive electrode 11, the separator 13, and the negative electrode 12 are all wound together; specifically, the positive electrode 11, the separator 13, and the negative electrode 12 can be wound into a cuboid structure or into a cylindrical structure, which can be selected according to the needs of the battery cell.
[0057] In some embodiments, the connector 142 has a relaxation section 1421, which is connected to the detector 141. The relaxation section 1421 is bent to release the stress when the detector 141 is wound, so as to avoid excessive stress on the detector 141, which may lead to a decrease in the performance of the fiber optic ring or even damage to the fiber.
[0058] For example, the relaxation segment 1421 can be bent into an arc or ring shape, and its length can be between 2mm and 3mm, specifically 2mm or 3mm; the length of the relaxation segment 1421 can also be other values, and this embodiment does not limit it.
[0059] In some embodiments, combined with Figure 6 It is known that the electrode assembly 1 includes an isolation component 16, which is disposed outside the connection portion 142 and is used to isolate the connection portion 142 from the electrolyte inside the battery cell.
[0060] By providing an isolation component 16 covering the connection portion 142, the isolation component 16 can be isolated from the electrolyte inside the battery cell, preventing the connection portion 142 from being corroded by the electrolyte, thereby greatly extending the service life of the connection portion 142.
[0061] In some embodiments, the isolation component 16 includes a flexible sealing layer 161, a curing layer 162, and a metal sleeve 163. The flexible sealing layer 161, the curing layer 162, and the metal sleeve 163 are sequentially sleeved over the connecting portion 142 to encapsulate the connecting portion 142. In the three-layer encapsulation structure outside the connecting portion 142, the flexible sealing layer 161 is responsible for stress buffering and primary sealing, the curing layer 162 is responsible for structural support and absolute barrier, and the metal sleeve 163 is responsible for mechanical protection and compression resistance. Together, they constitute a protective system that combines flexibility, rigidity, chemical inertness, and mechanical strength, ensuring the signal integrity and reliability of the connecting portion 142 during use.
[0062] For example, the cross-section of the connecting part 142 can be circular, rectangular or other shape, and the cross-section of the detection part 141 can be circular, rectangular or other shape.
[0063] In some embodiments, the flexible sealing layer 161 includes a fluororubber ring capable of buffering stress, preventing the optical fiber from being crushed or broken, and providing an initial seal; and / or, The cured layer 162 includes a nano-ceramic epoxy adhesive, which forms a hard and dense chemical barrier on the outside of the joint 142, completely preventing the penetration of corrosive electrolyte components such as hydrofluoric acid (HF) and protecting the joint 142 from corrosion; and / or, The metal sleeve 163 includes a titanium alloy sleeve, providing the strongest mechanical protection against the connection 142 being punctured by electrode burrs or crushed by external forces during assembly and use.
[0064] For example, when encapsulating the connector 142, a fluororubber ring is first pressed onto the outside of the connector 142 at a pressure of 5 MPa. Then, nano-ceramic epoxy resin is injected into the fluororubber ring, and finally, a titanium alloy sleeve is laser-welded to fit over the nano-ceramic epoxy resin; wherein, the nano-ceramic epoxy resin is cured at 80°C for 2 hours.
[0065] It needs to be explained that, in combination Figure 7 It can be seen that the process of detecting lithium plating information of negative electrode 12 is as follows: Emitting probe light: The fiber bundle 14 transmits a laser beam of a specific wavelength sequentially along the axial direction of the connector 142 and the detector 141, and at the detector 141, the probe point on the side perpendicular to the axial direction of the detector 141 illuminates the surface of the negative electrode 12 opposite to it (lateral coupling of the fiber).
[0066] Receiving reflected light: Under normal conditions (lithium ions are normally embedded in graphite), the surface of the negative electrode 12 is relatively smooth, and the light signal reflected back to the optical fiber is strong. However, when lithium plating occurs, metallic lithium precipitates in irregular forms such as dendrites, making the surface of the negative electrode 12 rough and uneven. This causes strong scattering and absorption of light, resulting in a significant weakening of the light signal reflected back to the detector 141, so that the detector 141 can detect the lithium plating information of the negative electrode 12.
[0067] Signal analysis and judgment: The light signal reflected back to the detection unit 141 can be transmitted to the monitoring module 2 through the connection unit 142. The monitoring module 2 can determine whether lithium plating has occurred at the negative electrode 12 corresponding to the detection point of the detection unit 141, as well as the degree of lithium plating and other lithium plating information by monitoring the change of the intensity of the reflected light in real time.
[0068] According to a second aspect of this application, a battery cell is provided, including the electrode assembly 1 of any of the above embodiments.
[0069] For example, the end of the connection portion 142 away from the detection portion 141 is located outside the battery cell for connection to the monitoring module 2.
[0070] According to a third aspect of this application, a battery is provided, including a battery cell as described in any of the above embodiments and a monitoring module 2, wherein the monitoring module 2 is connected to the connection portion 142 of the battery cell.
[0071] For example, the monitoring module is an optical sensing monitoring system that integrates optical hardware and software algorithms, capable of emitting optical signals through the fiber bundle 14, receiving return signals, and analyzing the signals to diagnose lithium plating.
[0072] In the description of this application, "and / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Additionally, the character " / ", unless otherwise specified, generally indicates that the related objects before and after it are in an "or" relationship.
[0073] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0074] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.
[0075] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.
[0076] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.
Claims
1. An electrode assembly, characterized in that, include: Negative electrode plate; A diaphragm, wherein the negative electrode sheet is disposed on one side of the diaphragm, and a mounting groove is provided on one side of the diaphragm; and, The fiber bundle has a connected detection part and a connecting part. The detection part is disposed in the mounting groove and is used to detect the lithium plating information of the negative electrode. The connecting part is used to connect to a monitoring module so that the lithium plating information can be transmitted to the monitoring module.
2. The electrode assembly according to claim 1, characterized in that, The electrode assembly further includes a protective layer disposed in the mounting groove and covering the detection part to isolate the detection part from the electrolyte located between the negative electrode and the diaphragm.
3. The electrode assembly according to claim 2, characterized in that, The ratio of the average depth of the mounting groove to the average thickness of the diaphragm is between 1 / 3 and 1 / 2; and / or, The ratio of the average thickness of the detection part to the average depth of the mounting groove is between 1 / 2 and 2 / 3; and / or, The ratio of the average thickness of the protective layer to the average depth of the mounting groove is between 1 / 3 and 1 / 2.
4. The electrode assembly according to claim 2, characterized in that, The protective layer includes adhesive, and the detection part can be fixed in the mounting groove by the adhesive. The adhesive includes at least one of UV adhesive, ion-conductive adhesive, and fluorinated adhesive.
5. The electrode assembly according to claim 4, characterized in that, An overflow space is formed between the end of the probe that is away from the connector and the end of the mounting groove, and the overflow space is able to receive at least part of the glue that overflows from the probe.
6. The electrode assembly according to claim 5, characterized in that, The distance between the end of the probe furthest from the connector and the end of the mounting groove is between 2mm and 3mm.
7. The electrode assembly according to any one of claims 1-6, characterized in that, The electrode assembly further includes a positive electrode plate, and the negative electrode plate and the positive electrode plate are respectively disposed on opposite sides of the separator.
8. The electrode assembly according to any one of claims 1-6, characterized in that, Both the diaphragm and the negative electrode are wound together, and the mounting groove is arranged circumferentially along the diaphragm so that the detection part is wound between the diaphragm and the negative electrode.
9. The electrode assembly according to claim 8, characterized in that, The connecting part has a relaxation section, which is connected to the detection part. The relaxation section is bent to release the stress when the detection part is wound.
10. The electrode assembly according to any one of claims 1-6, characterized in that, The electrode assembly includes an isolation component disposed outside the connection portion, which is used to isolate the connection portion from the electrolyte inside the battery cell.
11. The electrode assembly according to claim 10, characterized in that, The isolation component includes a flexible sealing layer, a curing layer, and a metal sleeve, which are sequentially fitted over the connecting portion to encapsulate it.
12. The electrode assembly according to claim 11, characterized in that, The flexible sealing layer includes a fluororubber ring; and / or, The cured layer comprises nano-ceramic epoxy adhesive; and / or, The metal sleeve includes a titanium alloy sleeve.
13. A battery cell, characterized in that, Includes the electrode assembly as described in any one of claims 1-12.
14. A battery, characterized in that, include: The battery cell as described in claim 13; and, A monitoring module is connected to the connection part of the battery cell.