Battery cell shell, battery cell and battery

Abstract

The utility model discloses a battery cell shell, a battery cell and a battery, the battery cell shell comprises a shell body, the shell body is provided with an inner side surface facing one side of a pole group, and the inner side surface is provided with a porous coating. According to the battery cell shell disclosed by the utility model, the porous coating is arranged on the inner side surface of the shell body and can absorb gas generated in the charging and discharging processes of the battery cell, so that the internal pressure of the battery cell shell is reduced, the expansive force of the battery cell is effectively reduced, the safety of the battery cell can be improved, and the service life of the battery cell can be prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery shell, a battery and a battery. Background Art

[0002] In the related technology, during the charge and discharge process of lithium-ion batteries, as lithium ions are inserted and released, some impurities will be generated on the surface of the electrode group. These impurities will decompose to produce gases. These gases will cause a certain outward pressure on the battery cell, causing the battery cell shell to expand. Due to the effect of the battery cell expansion force, the safety performance and life of the battery cell are seriously affected. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the utility model is to provide a battery cell shell, which effectively reduces the expansion force of the battery cell, thereby improving the safety and service life of the battery cell.

[0004] The battery cell shell according to the first embodiment of the utility model includes: a shell body, wherein the shell body has an inner side surface facing the pole group, and the inner side surface is provided with a porous coating.

[0005] According to the battery cell shell of the embodiment of the utility model, a porous coating is provided on the inner side of the shell body. The porous coating can absorb the gas generated by the battery cell during the charging and discharging process, reduce the internal pressure of the battery cell shell, effectively reduce the expansion force of the battery cell, and thus improve the safety and service life of the battery cell.

[0006] According to some embodiments of the present invention, the shell body further has an outer side surface facing away from the pole group, and the outer side surface is provided with a foam coating.

[0007] According to some embodiments of the present invention, the foaming coating is an insulating coating.

[0008] According to some embodiments of the present invention, the insulating coating is a polypropylene coating.

[0009] According to some embodiments of the present invention, the porous coating is a porous carbon coating.

[0010] According to some embodiments of the present invention, the pore size of the porous carbon coating is d, which satisfies 50nm≤d≤500nm.

[0011] According to some embodiments of the present invention, the thickness of the porous coating is a, satisfying 0.5 mm ≤ a ≤ 4 mm.

[0012] According to some embodiments of the present invention, the thickness of the foaming coating is b, satisfying 0.5mm≤b≤4mm.

[0013] The battery cell according to the embodiment of the second aspect of the utility model includes: the battery cell shell according to the embodiment of the first aspect of the utility model.

[0014] According to the battery cell of the embodiment of the utility model, the expansion force of the battery cell is effectively reduced by providing the battery cell housing, thereby improving the safety and service life of the battery cell.

[0015] A battery according to an embodiment of the third aspect of the utility model includes: a battery cell according to an embodiment of the second aspect of the utility model.

[0016] According to the battery of the embodiment of the utility model, by providing the above-mentioned battery core, the expansion force of the battery core is effectively reduced, the safety and service life of the battery core can be improved, and the safety and service life of the battery can be further improved.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0019] Figure 1 is a schematic diagram of a battery cell according to some embodiments of the utility model;

[0020] Figure 2 It is a schematic diagram of a battery cell casing according to some embodiments of the utility model.

[0021] Reference numerals:

[0022] 100. Battery cell;

[0023] 10. Battery cell shell; 1. Shell body; 11. Inner side; 111. Porous coating; 12. Outer side; 121. Foaming coating;

[0024] 20. Battery cell cover. DETAILED DESCRIPTION

[0025] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0026] In the description of the present utility model, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0027] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0028] Reference below Figure 1-Figure 2 A cell housing 10 according to an embodiment of the present invention is described.

[0029] According to the first embodiment of the utility model, the battery cell case 10 includes a case body 1, the case body 1 encloses a receiving cavity with one end open, the electrode group is located in the receiving cavity, and a battery cover plate 20 is also provided at the opening of the receiving cavity to seal the electrode group. The case body 1 and the battery cover plate 20 can seal the electrode group, prevent dust or water in the external environment from entering the electrode group, and improve the safety of the electrode group.

[0030] During the process of charging and discharging, the battery cell 100 will generate some impurities on the surface of the pole group. These impurities will decompose and generate gases. These gases will cause a certain outward pressure on the battery cell 100, causing the battery cell shell 10 to expand, seriously affecting the safety performance and service life of the battery cell 100. Therefore, the present application provides a porous coating 111 on the inner side 11 of the shell body 1, and the inner side 11 of the shell body 1 is the side of the shell body 1 facing the pole group. The porous coating 111 is located on the inner side 11 of the shell body 1, and the porous coating 111 has pores. The pores can absorb the gas generated by the battery cell 100 during the process of charging and discharging, reduce the expansion force of the gas on the battery cell shell 10 from the internal source, reduce the internal pressure of the battery cell shell 10, and effectively reduce the expansion force of the battery cell 100, thereby improving the safety and service life of the battery cell 100.

[0031] According to the battery cell shell 10 of the embodiment of the utility model, a porous coating 111 is provided on the inner side 11 of the shell body 1. The porous coating 111 can absorb the gas generated by the battery cell 100 during the charging and discharging process, reduce the internal pressure of the battery cell shell 10, and effectively reduce the expansion force of the battery cell 100, thereby improving the safety and service life of the battery cell 100.

[0032] According to some embodiments of the present invention, referring to Figure 1-Figure 2 The shell body 1 also has an outer side surface 12, which is the side of the shell body 1 away from the pole group, and the outer side surface 12 is provided with a foaming coating 121. When a single battery cell 100 is subjected to external impact or internal short circuit, the battery cell 100 fails and is accompanied by rapid internal temperature rise or even rupture of the battery cell shell 10. At this time, the high temperature, high pressure and released gas will act as reaction conditions to cause the foaming coating 121 outside the shell body 1 to undergo a foaming reaction, and the gas diffuses into the foaming coating 121 to generate a foaming material. The foaming material has a certain volume, which can isolate the failed battery cell 100 from other battery cells 100, effectively inhibit the transmission of high temperature to other battery cells 100, reduce the collision and extrusion caused by the expansion of the failed battery cell 100, and slow down the chain reaction of multiple battery cells 100.

[0033] By providing a porous coating 111 on the inner side 11 of the shell body 1 and a foaming coating 121 on the outer side 12 of the shell body 1, the porous coating 111 is used to absorb the gas during the discharge process of the charging core 100, and the foaming coating 121 can play a role in isolating the adjacent battery cells 100. After the battery cell 100 fails, the foaming coating 121 undergoes a foaming reaction, and the foaming coating 121 can isolate the failed battery cell 100 from other normal battery cells 100, and can prevent the spread of thermal runaway of the battery cell 100. Under the joint action of the porous coating 111 and the foaming coating 121, the safety performance and service life of the battery cell 100 can be improved.

[0034] According to some embodiments of the present invention, referring to Figure 1-Figure 2 The foam coating 121 is an insulating coating, and the insulating coating has insulating properties. The foam coating 121 has insulating properties and good surface protection, and can replace the insulating polyester film outside the battery cell housing 10. The foam coating 121 can not only play an insulating role, but also can isolate the battery cell 100 with thermal runaway from other normal battery cells 100 after the foam coating 121 is foamed.

[0035] According to some embodiments of the present invention, referring to Figure 1-Figure 2 The insulating coating is a polypropylene coating, which is composed of polypropylene material. The polypropylene material has good compressive energy absorption characteristics, good impact resistance, light weight and good insulation performance.

[0036] According to some embodiments of the present invention, referring to Figure 1-Figure 2 The porous coating 111 is a porous carbon coating. The porous carbon coating has abundant pore channels and a large specific surface area, and can absorb more gas, further reducing the internal pressure of the battery cell shell 10 and effectively reducing the expansion force of the battery cell 100.

[0037] According to some embodiments of the present invention, referring to Figure 1-Figure 2 The pore size of the porous carbon coating is d, which satisfies 50nm≤d≤500nm. For example, the pore size of the porous carbon coating can be 50nm, 100nm, 200nm, 300nm, 400nm or 500nm. When the pore size of the porous carbon coating satisfies this range, more gas can be absorbed, and the internal pressure of the battery cell housing 10 can be effectively reduced.

[0038] According to some embodiments of the present invention, referring to Figure 1-Figure 2 , the thickness of the porous coating 111 is a, which satisfies 0.5 mm ≤ a ≤ 4 mm. For example, the thickness of the porous coating 111 can be 0.5 mm, 1 mm, 2 mm, 3 mm or 4 mm. When the thickness of the porous coating 111 satisfies this range, it will not only not increase the thickness of the housing body 1, but also can absorb more gas.

[0039] According to some embodiments of the present invention, referring to Figure 1-Figure 2 , the thickness of the foaming coating 121 is b, which satisfies 0.5 mm ≤ b ≤ 4 mm. For example, the thickness of the foaming coating 121 can be 0.5 mm, 1 mm, 2 mm, 3 mm or 4 mm. When the thickness of the foaming coating 121 satisfies this range, not only will the thickness of the shell body 1 not be increased, but also the foaming of the foaming coating 121 can effectively isolate the failed battery cell 100 from other normal battery cells 100.

[0040] The method for preparing the battery cell shell 10 comprises the following steps:

[0041] After cleaning and pre-treating the surface of the shell body 1, the porous carbon material is evenly coated on the inner side 11 of the shell body 1 by a common spraying process, and the coating thickness is 0.5mm-4mm, and the polypropylene material is evenly coated on the outer side 12 of the shell body 1, and the coating thickness is 0.5mm-4mm;

[0042] The coated battery cell housing 10 is placed at room temperature to dry for 12 to 24 hours and then dried;

[0043] The battery is naturally cooled to room temperature to obtain a battery cell case 10 .

[0044] The battery cell 100 according to the second embodiment of the utility model includes: the battery cell shell 10 according to the first embodiment of the utility model.

[0045] According to the battery cell 100 of the embodiment of the utility model, by providing the battery cell housing 10 , the expansion force of the battery cell 100 is effectively reduced, thereby improving the safety and service life of the battery cell 100 .

[0046] A battery according to an embodiment of the third aspect of the utility model includes: a battery cell 100 according to the embodiment of the second aspect of the utility model.

[0047] According to the battery of the embodiment of the utility model, by providing the above-mentioned battery cell 100, the expansion force of the battery cell 100 is effectively reduced, the safety and service life of the battery cell 100 can be improved, and the safety and service life of the battery can be further improved.

[0048] In the description of this specification, the description with reference to the terms "some embodiments", "optionally", "further" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0049] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A battery cell casing, characterized in that: include: The shell body has an inner side surface facing the pole group, the inner side surface is provided with a porous coating, and the shell body also has an outer side surface away from the pole group, the outer side surface is provided with a foaming coating.

2. The battery cell casing according to claim 1, characterized in that: The foaming coating is an insulating coating.

3. The battery cell casing according to claim 2, characterized in that: The insulating coating is a polypropylene coating.

4. The battery cell casing according to claim 1, characterized in that: The porous coating is a porous carbon coating.

5. The battery cell casing according to claim 4, characterized in that: The pore size of the porous carbon coating is d, which satisfies 50nm≤d≤500nm.

6. The battery cell casing according to claim 1, characterized in that: The thickness of the porous coating layer is a, which satisfies 0.5 mm ≤ a ≤ 4 mm.

7. The battery cell casing according to claim 1, characterized in that: The thickness of the foaming coating is b, which satisfies 0.5 mm ≤ b ≤ 4 mm.

8. A battery cell, characterized in that: include: The battery cell shell according to any one of claims 1 to 7.

9. A battery, characterized in that: include: The battery cell according to claim 8.

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