Pole piece assembly, pole core, battery cell and battery

Abstract

The utility model discloses a pole piece assembly, a pole core, a battery cell and a battery. The pole piece assembly comprises a positive pole piece and a sampling module, wherein the sampling module comprises a composite film and a sampling piece; the composite film is fixedly arranged at the end part of the positive plate; the sampling piece is arranged in the composite membrane. By adopting the scheme, the abnormal condition of the battery cell can be found in time, so that the risk of fire and explosion of the battery system is reduced, and the problem that information in the battery cell is difficult to collect in time is solved. And meanwhile, the function of collecting the internal information of the battery cell in the later period can be conveniently realized on the basis of completely not changing the pole piece assembly. Moreover, the scheme is completely compatible with an existing battery cell mass production line, a manufacturing process and related equipment do not need to be newly added, the production cost can be greatly reduced, and mass production can be quickly promoted. In addition, according to the scheme, the sampling piece and the composite film are integrated into one sampling module, high integration is achieved, and cost is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field especially relates to a pole piece subassembly, pole core, electric core and battery. BACKGROUND

[0002] With the development of energy storage technology, the integration degree of energy storage system is required higher and higher. With the improvement of integration degree, the cost of energy storage system will also be reduced accordingly. The large capacity and large size electric core not only can reduce the watt-hour cost at the electric core end, but also can improve the unit area energy density at the system end, reduce the number of system integrated parts, thereby reducing the initial investment cost and the whole life cycle watt-hour cost of energy storage system. Therefore, the demand for large size and large capacity energy storage electric core is more and more urgent in the field of large energy storage, especially in the long time energy storage market.

[0003] However, with the increase of the capacity of the electric core, more heat is generated inside during the charging and discharging process, especially when the electric core is subjected to thermal abuse, electrical abuse and mechanical abuse, the heat generated and accumulated inside makes the temperature of the electric core rise rapidly, the risk of thermal runaway is intensified, and even fire and explosion occur. The greater the capacity, the greater the damage. Therefore, how to discover abnormal electric cores in advance and handle them in time to avoid the occurrence of thermal runaway and reduce the risk of fire and explosion of energy storage system has become the focus of the industry.

[0004] However, the current information collection and monitoring of the electric core mainly focuses on the outside of the electric core, which cannot collect the information inside the electric core in time and accurately, and the collected signals have hysteresis, so that abnormal electric cores cannot be discovered in time and corresponding protection treatment is carried out, resulting in thermal runaway of the electric core, even fire and explosion, and even major safety accidents. UTILITY MODEL CONTENTS

[0005] The utility model provides a kind of pole piece subassembly, pole core, electric core and battery to solve the problem of difficult to collect information inside electric core in time.

[0006] According to one aspect of the utility model, a pole piece assembly is provided, which includes a positive pole piece and a sampling module, the sampling module includes a composite film and a sampling piece;

[0007] The composite film is fixedly arranged at the end of the positive pole piece;

[0008] The sampling piece is arranged inside the composite film.

[0009] In the optional embodiment of the utility model, the thickness of the composite film is 50-300um.

[0010] In the optional embodiment of the utility model, the thickness of the composite film is 15-300um.

[0011] In the optional embodiment of the utility model, the composite film is one of PP composite film, PE composite film.

[0012] In the optional embodiment of the utility model, the sampling member includes one of a sensor and a sampling line.

[0013] In the optional embodiment of the utility model, the sensor includes at least one of an optical fiber sensor, a gas sensor, a MEMS sensor, a temperature sensor, a pressure sensor and a smoke sensor.

[0014] In the optional embodiment of the utility model, the sensor includes an optical fiber sensor, and the diameter of the optical fiber sensor is 30-250 um, or;

[0015] The sensor includes a MEMS sensor, the length and width of the MEMS sensor are both 2-5 mm, and the thickness of the MEMS sensor is 0.5-2.5 mm.

[0016] In the optional embodiment of the utility model, the sampling line includes at least one of a thermocouple, a thermal resistance, an optical fiber, a grating, a third electrode and a reference electrode, and / or;

[0017] The sampling line is packaged as an FPC flexible plate.

[0018] In the optional embodiment of the utility model, the sampling line includes a third electrode, the third electrode is a copper wire, and the diameter of the copper wire is 10-200 um.

[0019] In the optional embodiment of the utility model, the composite film has adhesive, and the composite film is pasted to the end of the positive plate through the adhesive.

[0020] According to another aspect of the utility model, a pole core is provided, the pole core includes a positive pole lug, a negative pole lug and the pole piece assembly of any one of the embodiments of the utility model, and the positive pole lug is electrically connected with the positive plate.

[0021] According to another aspect of the utility model, an electric core is provided, the electric core includes a cover plate and the pole core of any one of the embodiments of the utility model.

[0022] The cover plate has a positive pole column, a negative pole column and a sampling pole column.

[0023] The sampling member is electrically connected with the sampling pole column, the positive pole lug is electrically connected with the positive pole column, and the negative pole lug is electrically connected with the negative pole column.

[0024] According to another aspect of the utility model, a battery is provided, the battery includes the electric core of any one of the embodiments of the utility model.

[0025] The technical scheme of the embodiment of the utility model discloses a composite film is arranged at the end of the positive plate, and a sampling piece is arranged inside the composite film, so that after the electrode group is made into an electric core, the sampling piece can realize the function of collecting the internal information of the electric core, compared with arranging a sensor or a sampling line outside the electric core in the prior art, the present scheme can timely find the abnormal condition of the electric core, so as to reduce the risk of fire and explosion of the battery system, and solve the problem that the internal information of the electric core cannot be collected in time.

[0026] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the utility model, nor is it used to limit the scope of the utility model. Other features of the utility model will become apparent through the following description. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical scheme in the embodiments of the utility model, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can be obtained by those skilled in the art without creative labor.

[0028] Figure 1 is a structure schematic view of the electrode core formed by the electrode group provided in the first embodiment of the utility model;

[0029] Figure 2 is a structure schematic view of the electrode group provided in the first embodiment of the utility model;

[0030] Figure 3 is a structure schematic view of another electrode group provided in the first embodiment of the utility model;

[0031] Figure 4 is a structure schematic view of the cover plate of the electric core provided in the third embodiment of the utility model;

[0032] Figure 5 is a connection schematic view of the electrode core and the cover plate provided in the third embodiment of the utility model.

[0033] The components are as follows: 1. Cover plate; 11. Positive electrode post; 12. Negative electrode post; 13. Sampling electrode post; 14. Explosion-proof valve; 15. Cover plate body; 16. Liquid injection hole; 17. Adapter piece; 6. Sampling module; 61. Sampling component; 62. Composite membrane; 2. Electrode core; 2a. First electrode core; 2b. Second electrode core; 21. Positive electrode tab; 22. Negative electrode tab; 23. Positive electrode sheet; 4. Electrode tab solder mark; 5. Adapter piece solder mark. Detailed Implementation

[0034] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention 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 invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0035] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0036] Example 1

[0037] Embodiment 1 of this utility model provides an electrode assembly, such as Figure 1 and Figure 2 As shown, the electrode assembly includes a positive electrode 23 and a sampling module 6. The sampling module 6 includes a composite film 62 and a sampling element 61. The composite film 62 is fixedly disposed at the end of the positive electrode 23. The composite film 62 is a multilayer composite material formed by bonding two or more thin films together through a specific composite process. By disposing of the composite film 62 at the end of the positive electrode 23, it can act as a protective adhesive for the positive electrode 23 when the positive electrode 23 is wound into the electrode core 2. In some embodiments, the composite film 62 has an adhesive backing, and the composite film 62 is adhered to the end of the positive electrode 23 by the adhesive backing.

[0038] The sampling member 61 is arranged inside the composite film 62. The sampling member 61 refers to a component capable of collecting information inside the battery cell. In some embodiments, the sampling member 61 includes a sensor, which is a detection device capable of sensing measured information and converting the information into an electrical signal or other required form of information output according to certain rules. Different parameters can be detected according to different types of sensors. In some embodiments, the sampling member 61 includes a sampling line, which refers to a component capable of collecting and transmitting measured signals. By arranging the sampling member 61 inside the composite film 62, the composite film 62 can serve as the matrix support material and protective material of the sampling member 61, thereby fixing and protecting the sampling member 61.

[0039] In the above scheme, the composite film 62 is arranged at the end of the positive electrode sheet 23, and the sampling member 61 is arranged inside the composite film 62. Therefore, after the electrode sheet assembly is made into a battery cell, the sampling member 61 can collect information inside the battery cell. Compared with the related art in which a sensor or a sampling line is arranged outside the battery cell, the present scheme can timely discover abnormal conditions of the battery cell, thereby reducing the risk of fire and explosion of the battery system and solving the problem of difficult timely collection of information inside the battery cell. Meanwhile, since the end of the positive electrode sheet 23 in the related art is provided with a cutting protection adhesive, the present scheme integrates the sampling member 61 inside the composite film 62 arranged at the end of the positive electrode sheet 23, which can facilitate the collection of information inside the battery cell without changing the electrode sheet assembly. Meanwhile, the present scheme is fully compatible with the existing production line of the battery cell, does not need to add manufacturing procedures and related equipment, can greatly reduce the production cost, and can be quickly put into mass production. Meanwhile, the present scheme integrates the sampling member 61 and the composite film 62 into a sampling module 6, which realizes high integration and reduces the cost.

[0040] In an optional embodiment of the present application, the thickness of the composite film 62 can be microns to millimeters. In some embodiments, the thickness of the composite film 62 is 50-300 um. Preferably, the thickness of the composite film 62 is 15-300 um. Therefore, the positive electrode sheet 23 and the sampling member 61 can be protected, and the sampling member 61 can be fixed.

[0041] In an optional embodiment of the present application, the composite film 62 is one of a PP composite film and a PE composite film. The PE composite film has excellent corrosion resistance, electrical insulation and ductility, and good low-temperature performance. The PP composite film has good rigidity and impact resistance, and relatively high strength and hardness, and good heat resistance. Therefore, by making the composite film 62 one of the PP composite film and the PE composite film, the internal sampling member 61 can be better protected from corrosion by the electrolyte.

[0042] In an optional embodiment of the present application, as shown in Figure 1 andFigure 2 As shown in the figure, the sensor includes at least one of an optical fiber sensor, a gas sensor, a MEMS sensor, a temperature sensor, a pressure sensor, and a smoke sensor. That is, different sensors with different functions can be set according to specific detection requirements to achieve different detection requirements to detect different parameters inside the battery cell. For example, when the pressure inside the battery cell needs to be detected, the sensor includes a pressure sensor, and the pressure inside the battery cell can be detected through the pressure sensor. It can be understood that in other embodiments, when other parameters need to be detected, the sensor can be other types of sensors, which are not limited here.

[0043] In some embodiments, the sensor includes an optical fiber sensor, and the diameter of the optical fiber sensor is 30-250um. The optical fiber sensor can detect a variety of physical quantities, including pressure, temperature, flow, sound wave, and liquid level. By embedding the optical fiber sensor as the sampling piece 61 in the composite film 62 at the end of the positive electrode sheet 23, when the positive electrode sheet 23 is wound into a battery cell, the optical fiber sensor can detect a variety of different parameters inside the battery cell. At the same time, the diameter of the optical fiber sensor is 30-250um, which can be easily integrated inside the composite film 62.

[0044] In some embodiments, as shown in the figure, Figure 3 The sensor includes a MEMS sensor, and the length and width of the MEMS sensor are both 2-5mm, and the thickness of the MEMS sensor is 0.5-2.5mm. The MEMS sensor can detect a variety of physical quantities, including pressure, temperature, humidity, acceleration, angular velocity, etc. The MEMS sensor is a kind of miniaturized sensor, which is manufactured by using micro-electro-mechanical system (MEMS) technology, and has the advantages of small size, low power consumption, and fast response speed. By embedding the MEMS sensor as the sampling piece 61 in the composite film 62 at the end of the positive electrode sheet 23, when the positive electrode sheet 23 is wound into a battery cell, the MEMS sensor can detect a variety of different parameters inside the battery cell. At the same time, the length and width of the MEMS sensor are both 2-5mm, and the thickness of the MEMS sensor is 0.5-2.5mm, which can be easily integrated inside the composite film 62.

[0045] In the optional embodiment of the utility model, as shown in the figure, Figure 1 And Figure 2As shown, the sampling line includes at least one of a thermocouple, a thermal resistance, an optical fiber, a grating, a third electrode, and a reference electrode, that is, different functional sampling lines can be set according to specific detection requirements to detect different parameters inside the battery cell. In some embodiments, the sampling line includes a third electrode, and the third electrode is a copper wire with a diameter of 10-200 um. Through the third electrode, the potential of the negative electrode inside the battery cell can be monitored in real time, and lithium precipitation anomalies of the negative electrode can be found in time to eliminate safety hazards. Since the diameter of the copper wire is 10-200 um, it can be easily integrated inside the composite film 62. It can be understood that in other embodiments, when other parameters need to be detected, the sampling line can also be other types of components, and the specific structure of the sampling line is not specifically limited here, but is only used as an example.

[0046] In an optional embodiment of the present application, the sampling line is packaged as an FPC flexible board. By packaging the sampling line as an FPC flexible board, it can have good flexibility, heat dissipation, weldability, easy to assemble, high wiring density, and low comprehensive cost. In some embodiments, an electrolyte corrosion resistant coating can be applied to the FPC flexible board, and then a back adhesive treatment is performed to replace the cutting protection glue during the winding of the electrode piece assembly.

[0047] Embodiment two

[0048] As shown in Figure 1 and Figure 2 Embodiment two of the present application provides an electrode core 2, which includes a positive electrode lug 21, a negative electrode lug 22, and an electrode piece assembly of any embodiment of the present application, and the positive electrode lug 21 is electrically connected with the positive electrode piece 23. Among them, since the electrode core 2 is formed by winding the electrode piece assembly, at this time the sampling module 6 is located inside the electrode core 2, realizing the function of collecting the information inside the electrode core 2 conveniently. Since the battery cell is made of the electrode core 2, the information collected at this time is the information inside the battery cell. Compared with the related art of arranging sensors or sampling lines outside the battery cell, the present scheme can timely find abnormal conditions of the battery cell to reduce the risk of fire and explosion of the battery system, and solves the problem of difficult timely collection of information inside the battery cell.

[0049] Embodiment three

[0050] Embodiment three of the present application provides a battery cell, as shown in Figure 1 and Figure 4 The battery cell includes a cover plate 1 and an electrode core 2 of any embodiment of the present application; as shown in Figure 4 and Figure 5 The cover plate 1 has a positive electrode column 11, a negative electrode column 12, and a sampling electrode column 13; the sampling piece 61 is electrically connected with the sampling electrode column 13, the positive electrode lug 21 is electrically connected with the positive electrode column 11, and the negative electrode lug 22 is electrically connected with the negative electrode column 12.

[0051] Wherein, since the sampling member 61 is electrically connected with the sampling pole 13, and the sampling member 61 is located inside the battery cell, the sampling member 61 can collect the information inside the battery cell, and transmit to the external signal processor through the sampling pole 13. Compared with the related art of arranging the sensor or sampling line outside the battery cell, the present scheme can timely find the abnormal condition of the battery cell, so as to reduce the risk of fire and explosion of the battery system, and solve the problem of difficult to collect the information inside the battery cell in time.

[0052] In some embodiments, the cover plate 1 further comprises a cover plate body 15, a liquid injection hole 16 and an explosion-proof valve 14, the liquid injection hole 16, the explosion-proof valve 14, the positive pole 11, the negative pole 12 and the sampling pole 13 are all arranged on the cover plate body 15. Wherein, the liquid injection hole 16 is used for injecting electrolyte into the battery cell. The explosion-proof valve 14 is used for preventing explosion caused by excessive pressure inside the battery cell.

[0053] The following describes the manufacturing process of the battery cell according to the present scheme with a specific embodiment. As shown in Figure 1 and Figure 2 , the sampling member 61 is first built into the composite film 62 to form a sampling module 6, then the sampling module 6 is pasted to the end of the cut positive pole 23 through the back glue, then the sampling module 6 is wound to form the pole core 2. As shown in Figure 1 , the winding mode is the same as that in the related art, the difference is that the cut protection glue in the related art is replaced by the sampling module 6.

[0054] As shown in Figure 4 and Figure 5 , then the wound pole core 2 is assembled and welded with the cover plate 1. The pole core 2 comprises a first pole core 2a and a second pole core 2b. The positive pole lug 21 of the first pole core 2a and the positive pole lug 21 of the second pole core 2b are welded together with the adapter piece 17 through the pole lug welding mark 4 by ultrasonic welding, then the adapter piece 17 connected with the positive pole lug 21 is welded together with the positive pole 11 of the cover plate 1 through the adapter piece welding mark 5. The negative pole lug 22 of the first pole core 2a and the negative pole lug 22 of the second pole core 2b are welded together with the adapter piece 17 through the pole lug welding mark 4 by ultrasonic welding, then the adapter piece 17 connected with the negative pole lug 22 is welded together with the negative pole 12 of the cover plate 1 through the adapter piece welding mark 5. Then the sampling member 61 of the sampling module 6 is connected together with the sampling pole 13 on the cover plate 1, and the connection mode can be welding. Subsequently, the battery cell is formed through the processes of core combining, glue wrapping, Mylar wrapping, shell entering, sealing periphery welding, baking, liquid injection, formation, and capacity distribution, etc. The subsequent processes of core combining, glue wrapping, Mylar wrapping, shell entering, sealing periphery welding, baking, liquid injection, formation, and capacity distribution, etc. are completely consistent with the existing battery cell, and will not be described here.

[0055] Embodiment four

[0056] The utility model discloses a battery, the battery includes the electric core of any embodiment of the utility model.

[0057] Wherein, as Figure 4 And Figure 5 As shown in the drawing, the sampling module 6 is connected to the outside of the electric core through the sampling pole 13 arranged on the cover plate 1, so that the battery can conveniently obtain the information inside the electric core through the sampling pole 13, and the external signal processor can be conveniently connected with the sampling pole 13. The external signal processor can be integrated in the BMS system of the battery, so that the internal pressure, temperature, gas, smoke particles and other index parameters of the electric core can be collected in real time, and the internal information is transmitted to the external processor in real time for analysis and monitoring. Compared with the current traditional external sensor, the built-in sampling module 6 can not only find abnormal electric cores in advance, but also can monitor more electric core information, such as the internal pressure of the electric core, the gas composition generated in the electric core and other parameters related to the safety performance of the electric core. Therefore, the risk of fire and explosion caused by thermal runaway of the electric core can be avoided, and the safety and reliability of the battery can be greatly improved.

[0058] It should be understood that various forms of the flow shown above can be used to reorder, add or delete steps. For example, each step described in the utility model can be executed in parallel, sequentially or in a different order, as long as the desired results of the technical solution of the utility model can be achieved, which is not limited herein.

[0059] The above specific embodiments do not constitute a limitation on the protection scope of the utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. A pole piece assembly, characterized by, The positive electrode sheet and the sampling module are included, and the sampling module includes a composite film and a sampling piece. The composite film is fixedly arranged at the end of the positive electrode sheet. The sampling piece is arranged inside the composite film. The composite film is one of a PP composite film and a PE composite film. The composite film has an adhesive, and the composite film is attached to the end of the positive electrode sheet through the adhesive.

2. The pole piece assembly of claim 1, wherein, The thickness of the composite film is 50-300um.

3. The pole piece assembly of claim 2, wherein, The thickness of the composite film is 15-300um.

4. The pole piece assembly of any one of claims 1 to 3, wherein, The sampling piece includes one of a sensor and a sampling line.

5. The pole piece assembly of claim 4, wherein, The sensor includes at least one of an optical fiber sensor, a gas sensor, a MEMS sensor, a temperature sensor, a pressure sensor, and a smoke sensor.

6. The pole piece assembly of claim 5, wherein, The sensor includes an optical fiber sensor, and the diameter of the optical fiber sensor is 30-250um. The sensor includes a MEMS sensor, and the length and width of the MEMS sensor are both 2-5mm, and the thickness of the MEMS sensor is 0.5-2.5mm.

7. The pole piece assembly of claim 4, wherein, The sampling line includes at least one of a thermocouple, a thermal resistance, an optical fiber, a grating, a third electrode, and a reference electrode. The sampling line is packaged as an FPC flexible board.

8. The pole piece assembly of claim 7, wherein, The sampling line includes a third electrode, and the third electrode is a copper wire, and the diameter of the copper wire is 10-200um.

9. A core, characterized by: The positive electrode tab, the negative electrode tab, and the electrode sheet assembly of any one of claims 1-8 are included, and the positive electrode tab is electrically connected to the positive electrode sheet.

10. An electric cell characterized by: The cover plate and the electrode core of claim 9 are included. The cover plate has a positive electrode column, a negative electrode column, and a sampling electrode column. The sampling piece is electrically connected to the sampling electrode column, the positive electrode tab is electrically connected to the positive electrode column, and the negative electrode tab is electrically connected to the negative electrode column.

11. A battery, characterized by The electric core of claim 10 is included.

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