Lithium battery with leakage detection function

Abstract

The utility model discloses a lithium battery with leakage detection function, pool casing and battery management system still include leakage detection structure layer, leakage detection structure layer sets up between adjacent lithium battery monomer or sets up between lithium battery monomer and battery casing inner wall, leakage detection structure layer includes insulating base layer, leakage substance collection layer and at least a pair of detection electrode. Through built -in leakage detection structure layer, realize lithium battery leakage hidden danger's accurate capture and efficient protection, and the beneficial effect is remarkable. Its leakage substance collection layer can targeted adsorption leaky electrolyte, accommodate lithium dendrite, combines porous surface design, and leakage substance capture efficiency is improved greatly, and the problem of traditional detection lag, misjudgment is solved. Multilayer composite collection layer and conductive fiber layer optimize electrode contact, make resistance change signal clear measurable, and the detection sensitivity is improved significantly.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, specifically to a lithium battery with leakage detection function. Background Technology

[0002] Lithium-ion batteries, as core energy storage components in the new energy field, are widely used in electric vehicles, energy storage power stations, and other scenarios. However, their safety performance has always been a focus of industry attention. During long-term charge-discharge cycles, existing lithium-ion batteries are prone to electrolyte leakage or abnormal lithium dendrite growth due to problems such as separator damage and electrode burrs, which can lead to leakage between individual cells, short circuits, or even fires.

[0003] Currently, lithium battery leakage detection relies heavily on current / voltage anomaly monitoring in the battery management system or externally installed insulation resistance sensors. These methods suffer from drawbacks such as slow response and difficulty in accurately locating internal leakage sources. Especially for trace electrolyte leaks and early lithium dendrite growth, traditional detection methods are prone to false alarms or missed alarms, failing to provide early warnings of potential risks. This not only affects battery lifespan but also poses a serious threat to equipment operational safety. Summary of the Invention

[0004] In order to overcome the shortcomings of existing technical solutions, this utility model provides a lithium battery with leakage detection function, which can effectively solve the problems mentioned in the background technology.

[0005] The technical solution adopted by this utility model to solve its technical problem is: A lithium battery with leakage current detection function includes a lithium battery cell, a battery casing, and a battery management system, and further includes a leakage current detection structure layer. The leakage current detection structure layer is disposed between adjacent lithium battery cells or between a lithium battery cell and the inner wall of the battery casing. The leakage current detection structure layer includes: An insulating substrate layer, wherein the insulating substrate layer is conductive to the surface of the lithium battery cell; A leakage material collection layer is applied to the conductive surface of the insulating substrate, and the leakage material collection layer is made of a material that can adsorb or contain electrolyte or lithium dendrites. At least one pair of detection electrodes are embedded inside the leakage material collection layer or attached to the outer surface of the leakage material collection layer, and the detection electrodes are electrically connected to the detection circuit of the battery management system.

[0006] As a further description of the above technical solution, the leakage current collection layer is a multi-layer composite structure, and the leakage current collection layer includes: The adsorption layer near the insulating substrate is composed of an electrophilic material with a microporous or mesoporous structure. The conductive fiber layer disposed on the outside of the adsorption layer is woven or stacked from conductive metal fibers or carbon fibers. The containment layer disposed on the outside of the conductive fiber layer is composed of a flexible polymer matrix capable of containing lithium dendrites. The detection electrode is at least partially disposed in the conductive fiber layer.

[0007] As a further description of the above technical solution, the surface of the leakage material collection layer facing the lithium battery cell has a porous structure, and the pore size of the porous structure ranges from 0.1 μm to 50 μm.

[0008] As a further description of the above technical solution, the leakage current detection structure layer also includes an insulating sealing frame, which is arranged around the edge of the insulating base layer, the leakage current collection layer and the detection electrode, and forms a sealed connection with the insulating base layer.

[0009] As a further description of the above technical solution, a high insulation barrier layer is also provided between the leakage detection structure layer and the lithium battery cell.

[0010] As a further description of the above technical solution, the battery management system also includes a leakage current alarm, which is connected to the detection circuit signal.

[0011] As a further description of the above technical solution, the leakage material collection layer also includes self-healing microcapsules containing an insulating sealant.

[0012] Compared with the prior art, the beneficial effects of this utility model are: The lithium battery with leakage detection function of this utility model has at least one of the following beneficial effects during use: By incorporating a built-in leakage detection structure layer, it achieves precise detection and efficient protection against potential lithium battery leakage, yielding significant benefits. Its leakage material collection layer can specifically adsorb leaking electrolyte and accommodate lithium dendrites. Combined with a porous surface design of 0.1μm-50μm, it greatly improves the efficiency of leakage material capture, solving the problems of lag and misjudgment in traditional detection methods. The multi-layered composite collection layer and conductive fiber layer optimize electrode contact, making resistance change signals clearly measurable and significantly improving detection sensitivity.

[0013] The insulating sealing frame and high-insulation barrier layer form a double protection, preventing signal crosstalk and leakage current propagation without affecting normal battery charging and discharging. Combined with a leakage current alarm for proactive early warning, the self-healing microcapsules quickly seal leakage points, effectively preventing fault escalation and reducing the risk of short circuits and fires. The detection structure layer offers flexible installation, adaptable to different lithium battery specifications. The multi-layer sealing design ensures long-term stable operation in complex environments while reducing lithium dendrite damage to the separator, delaying battery performance degradation, and comprehensively improving the safety and reliability of lithium battery use. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the first overall structure of a lithium battery with leakage detection function according to the present invention; Figure 2 This is a schematic diagram of the second overall structure of a lithium battery with leakage detection function according to the present invention; Figure 3 This is a schematic diagram of the second integral side structure of a lithium battery with leakage detection function according to the present invention; Figure 4 This is a partial structural diagram of a lithium battery with leakage detection function according to the present invention.

[0015] Numbering on the map: 1. Battery casing; 101. Lithium battery cell; 102. Insulating sealing frame; 103. High insulation barrier layer; 2. Battery management system; 201. Leakage alarm; 3. Leakage detection structure layer; 301. Insulating base layer; 302. Leakage material collection layer; 303. Detection electrode; 304. Adsorption layer; 305. Conductive fiber layer. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] like Figure 1-4 As shown, this utility model provides a lithium battery with leakage detection function, including a lithium battery cell 101, a battery casing 1, and a battery management system 2, and also includes a leakage detection structure layer 3. The leakage detection structure layer 3 is disposed between adjacent lithium battery cells 101 or between a lithium battery cell 101 and the inner wall of the battery casing 1. The leakage detection structure layer 3 includes: An insulating substrate 301 has a conductive surface facing the lithium battery cell 101. A leakage material collection layer 302 is disposed on the conductive surface of the insulating substrate layer 301. The leakage material collection layer 302 is made of a material that can adsorb or contain electrolyte or lithium dendrites. When a lithium battery leaks current, electrolyte leakage or abnormal lithium dendrite growth is likely to occur. The leakage material collection layer 302 directly contacts the lithium battery cell 101 through its porous structure (0.1μm-50μm pore size). Its adsorption layer 304 (electrolyte-friendly microporous material) quickly adsorbs the leaking electrolyte, the containment layer (flexible polymer) encapsulates the growing lithium dendrites, and the conductive fiber layer 305 enhances the contact conductivity between the leakage material and the detection electrode 303.

[0018] At least one pair of detection electrodes 303 are embedded inside the leakage material collection layer 302 or attached to the outer surface of the leakage material collection layer 302, and the detection electrodes 303 are electrically connected to the detection circuit of the battery management system 2.

[0019] The detection electrode 303 is embedded in the conductive fiber layer 305 or attached to the surface of the collection layer. Under normal conditions, the electrodes maintain a high resistance due to the insulating properties of the insulating substrate layer 301 and the collection layer. When the collection layer adsorbs electrolyte or encapsulates lithium dendrites, the resistance value between the electrodes decreases significantly or undergoes a sudden change. The detection electrode 303 transmits the resistance change signal to the detection circuit of the battery management system 2.

[0020] The battery management system 2 compares the resistance to a preset threshold. When the resistance is detected to be below the threshold or there is a sudden change, the leakage alarm 201 is triggered to issue an alarm signal. If the collection layer contains self-healing microcapsules, the local stress caused by leakage will cause the microcapsules to rupture, releasing insulating sealant to seal and repair the leakage point, preventing further leakage. The insulating sealing frame 102 and the high insulating barrier layer 103 form a double protection, preventing the detection structure layer itself from affecting the normal operation of the battery, while also preventing leakage from spreading.

[0021] This embodiment uses a built-in leakage detection structure layer 3 to capture potential leakage hazards such as electrolyte leakage or lithium dendrite growth in real time. Combined with the battery management system 2, it realizes leakage early warning and auxiliary repair, which greatly improves the safety and reliability of lithium battery use.

[0022] Furthermore, the leakage current collection layer 302 is a multi-layer composite structure, and the leakage current collection layer 302 includes: The adsorption layer 304 near the insulating substrate layer 301 is composed of an electrophilic material with a microporous or mesoporous structure. The adsorption layer 304 utilizes the material's hydrophilicity and porous structure to quickly adsorb the electrolyte (which is mostly an organic conductive liquid) leaking from the lithium battery cell 101, ensuring that the leaked material is captured as soon as possible and preventing its spread.

[0023] The conductive fiber layer 305 disposed on the outside of the adsorption layer 304 is woven or laid up from conductive metal fibers or carbon fibers. It is conductive. When the adsorption layer 304 adsorbs electrolyte (conductive) or lithium dendrites (conductive) and extends to this point, it can transfer the conductivity of the leakage material to the detection electrode 303 embedded therein, thereby strengthening the electrical contact between the electrode and the leakage material (solving the problem of weak signal caused by insufficient conductivity of a single adsorption layer 304).

[0024] The containment layer disposed on the outside of the conductive fiber layer 305 is composed of a flexible polymer matrix capable of containing lithium dendrites. The containment layer utilizes flexibility and a certain degree of ductility to encapsulate lithium dendrites (which are needle-shaped conductive crystals that easily pierce the membrane) that grow from the monomer, restricting their further growth and diffusion. At the same time, it keeps the lithium dendrites in contact with the conductive fiber layer 305 to ensure stable electrical signals.

[0025] The detection electrode 303 is at least partially disposed in the conductive fiber layer 305.

[0026] After the electrode portion is embedded in the conductive fiber layer 305, the resistance change of the fiber layer caused by the introduction of leakage material can be directly sensed, avoiding detection failure caused by "poor contact" between the electrode and the leakage material.

[0027] Furthermore, the surface of the leakage material collection layer 302 facing the lithium battery cell 101 has a porous structure, and the pore size of the porous structure ranges from 0.1 μm to 50 μm.

[0028] The electrolyte leaking from lithium batteries consists of small liquid molecules (typically <0.1 μm in diameter). Pores larger than 0.1 μm allow the electrolyte to rapidly penetrate into the internal adsorption layer 304. Lithium dendrites are micron-sized needle-like crystals (initially about 1-10 μm in diameter, reaching up to 50 μm in maturity). Pores smaller than 50 μm guide the growth of lithium dendrites into the collection layer (rather than diffusing into other areas of the battery), while avoiding insufficient structural strength of the collection layer due to excessively large pore sizes. The porous structure increases the contact area between the collection layer and the lithium battery cell 101, improving the capture efficiency of leaked material (even tiny leaks can be captured through the porous channels).

[0029] Furthermore, the leakage current detection structure layer 3 also includes an insulating sealing frame 102, which surrounds the edge of the insulating base layer 301, the leakage current material collection layer 302 and the detection electrode 303, and forms a sealed connection with the insulating base layer 301.

[0030] It prevents the electrolyte or lithium dendrites captured by the collection layer from overflowing from the edge of the structural layer, avoids the diffusion of leakage material to other areas of the battery (such as adjacent cells or inside the casing), and prevents secondary leakage or interference with other detection units.

[0031] It forms a closed space with the insulating substrate layer 301, ensuring that the leakage material in the collection layer only interacts with the detection electrode 303 of this structural layer, avoiding signal crosstalk between different detection units. At the same time, it enhances the overall strength of the structural layer and prevents the collection layer or electrode from falling off when the battery vibrates or is impacted.

[0032] Furthermore, a high-insulation barrier layer 103 is provided between the leakage detection structure layer 3 and the lithium battery cell 101.

[0033] The high-insulation barrier layer 103 blocks the interference of electric field / charge transfer during normal operation of the lithium battery cell 101 on the detection electrode 303. The high-insulation material itself has the characteristics of high and low temperature resistance and chemical corrosion resistance. Even if the detection structure layer fails, it can still serve as an additional insulation barrier to reduce the risk of short circuit between cells.

[0034] Furthermore, the battery management system 2 also includes a leakage current alarm 201, which is connected to the detection circuit signal.

[0035] When the detection circuit detects that the resistance value between the detection electrodes 303 is lower than a preset threshold or / and the resistance value changes abruptly, the leakage current alarm 201 triggers an alarm signal.

[0036] The alarm system provides early warning of battery leakage through audible and visual alarms (such as buzzers and warning lights) or electrical signal outputs (such as CAN bus notifications to the vehicle controller). Early warning can prevent minor leakage from developing into serious malfunctions, reducing the frequency of battery repairs or replacements.

[0037] Furthermore, the leakage material collection layer 302 also includes self-healing microcapsules containing an insulating sealant.

[0038] Self-healing microcapsules (such as epoxy resin or silicone rubber sealants encapsulated in urea-formaldehyde resin) can quickly fill leakage points (such as gaps in the monomer shell or damage to the diaphragm). After curing, they form an insulating sealing layer, blocking further electrolyte leakage or the path of continuous lithium dendrite growth. The sealant also isolates the leaking material from the detection electrode 303, indirectly inhibiting the continuous decrease in resistance and buying time for subsequent processing.

[0039] In summary, the leakage material collection layer 302 specifically adsorbs electrolyte and accommodates lithium dendrites, directly capturing the leakage source and avoiding the lag and misjudgment of traditional detection methods. The conductive fiber layer 305 optimizes the contact between the electrode and the leakage material, ensuring clear and measurable resistance change signals and significantly improving detection sensitivity. It provides early warning of potential leakage hazards, preventing short circuits, fires, and other safety accidents caused by leakage, thus reducing usage risks. The self-healing microcapsules and insulating sealing structure form active protection, quickly blocking even minor leakage and extending the battery's safe service life. The leakage detection structure layer 3 uses an insulating base layer 301 and a high-insulation barrier layer 103, without affecting the normal charge-discharge cycle of the lithium battery cell 101. While accommodating lithium dendrites, the collection layer reduces puncture damage to the battery separator caused by lithium dendrites, delaying battery performance degradation. The detection structure layer can be flexibly placed between battery cells or between a cell and the casing, adapting to different lithium battery designs. The multi-layer composite structure and sealing design ensure long-term stability of the detection function, unaffected by the complex internal environment of the battery (temperature, humidity, etc.).

[0040] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A lithium battery with leakage current detection function, comprising a lithium battery cell, a battery casing, and a battery management system, characterized in that, It also includes a leakage current detection structure layer, which is disposed between adjacent lithium battery cells or between a lithium battery cell and the inner wall of the battery casing. The leakage current detection structure layer includes: An insulating substrate layer, wherein the insulating substrate layer is conductive to the surface of the lithium battery cell; A leakage material collection layer is applied to the conductive surface of the insulating substrate, and the leakage material collection layer is made of a material that can adsorb or contain electrolyte or lithium dendrites. At least one pair of detection electrodes are embedded inside the leakage material collection layer or attached to the outer surface of the leakage material collection layer, and the detection electrodes are electrically connected to the detection circuit of the battery management system.

2. A lithium battery with leakage detection function according to claim 1, characterized in that: The leakage current collection layer is a multi-layer composite structure, comprising: The adsorption layer near the insulating substrate is composed of an electrophilic material with a microporous or mesoporous structure. The conductive fiber layer disposed on the outside of the adsorption layer is woven or stacked from conductive metal fibers or carbon fibers. The containment layer disposed on the outside of the conductive fiber layer is composed of a flexible polymer matrix capable of containing lithium dendrites. The detection electrode is at least partially disposed in the conductive fiber layer.

3. A lithium battery with leakage detection function according to claim 1 or 2, characterized in that: The surface of the leakage material collection layer facing the lithium battery cell has a porous structure with a pore size ranging from 0.1 μm to 50 μm.

4. A lithium battery with leakage detection function according to claim 1, characterized in that: The leakage current detection structure layer also includes an insulating sealing frame, which surrounds the edge of the insulating base layer, the leakage current collection layer and the detection electrode, and forms a sealed connection with the insulating base layer.

5. A lithium battery with leakage detection function according to claim 1, characterized in that: A high-insulation barrier layer is also provided between the leakage detection structure layer and the lithium battery cell.

6. A lithium battery with leakage detection function according to claim 1, characterized in that: The battery management system also includes a leakage current alarm, which is connected to the detection circuit signal.

7. A lithium battery with leakage detection function according to claim 1, characterized in that: The leakage material collection layer also includes self-healing microcapsules containing an insulating sealant.

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