Top cover assembly and manufacturing method thereof, energy storage device and electric equipment

Abstract

The invention discloses a top cover assembly, an energy storage device and electric equipment, and relates to the technical field of energy storage. The top cover assembly comprises a top cover, a pole, an injection molding layer and a first insulating oxide layer, the top cover comprises a first surface and a second surface which are opposite to each other, and a pole hole penetrating through the first surface and the second surface is formed in the top cover; nanoscale micropores are formed in the hole wall of the pole hole and the area, surrounding the pole hole, on the first surface; the pole is arranged in the pole hole in a penetrating manner; the injection molding layer is formed on the nanoscale micropores of the hole wall, is positioned between the hole wall and the peripheral surface of the pole and is positioned on an area, where the nanoscale micropores are formed, of the first surface of the top cover; the first insulating oxide layer is formed on the area, not covered by the injection molding layer, of the first surface of the top cover; and the heat dissipation performance of the top cover assembly is improved.

Description

Technical Field

[0001] The present application relates to the field of energy storage technology, and in particular to a top cover assembly, a method for manufacturing a top cover assembly, an energy storage device, and electrical equipment. Background Art

[0002] Secondary batteries, also known as rechargeable batteries or storage batteries, are batteries that can be recharged to activate the active materials after being discharged and continue to be used. The recyclable nature of secondary batteries has made them gradually become the main power source for electrical equipment.

[0003] As the demand for secondary batteries gradually increases, people have higher and higher requirements for their performance in all aspects, especially for battery cycle performance and safety performance. The heat dissipation problem during the battery cycle is an important factor affecting the battery safety performance.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] A main purpose of the present application is to provide a top cover assembly, which improves the heat dissipation performance of the top cover assembly.

[0006] In order to achieve the above application purpose, this application adopts the following technical solutions:

[0007] According to one aspect of the present application, a top cover assembly is provided, the top cover assembly comprising:

[0008] A top cover, the top cover comprising a first surface and a second surface opposite to each other, and a pole hole penetrating the first surface and the second surface is formed on the top cover;

[0009] A pole, wherein the pole is inserted into the pole hole;

[0010] An insulating member, the insulating member is formed on the hole wall of the pole hole and is located between the hole wall and the outer peripheral surface of the pole, and on the area surrounding the pole hole on the first surface of the top cover;

[0011] A first insulating oxide layer is formed on a region of the first surface of the top cover that is not covered by the insulating member.

[0012] In the top cover assembly provided in this embodiment, the insulating member is formed on the hole wall of the pole hole and the area surrounding the pole hole on the first surface. The insulating member located on the hole wall of the pole hole forms insulation between the pole and the top cover, and the insulating member located on the area surrounding the pole hole forms insulation between the top covers when the adapter is subsequently set; on the first surface of the top cover, the insulating member is only located in the area surrounding the pole hole and does not completely cover the first surface of the top cover; insulation is formed by setting a first insulating oxide layer on the area of ​​the first surface of the top cover that is not covered by the insulating member, and the thickness of the first insulating oxide layer is greatly reduced relative to the insulating member, so that the heat generated in the battery can be dissipated through the top cover more quickly, thereby improving the heat dissipation performance of the top cover assembly; in addition, by relatively reducing the area of ​​the insulating member, it is avoided that the insulating member forms a structure such as a bump that blocks the flow of gas, so that when the battery cell produces gas due to thermal runaway, the gas can be discharged from the explosion-proof valve of the top cover in time, reducing the risk of battery explosion and improving the safety of the battery.

[0013] According to one embodiment of the present application, nanoscale micropores are formed on the hole wall of the pole hole and the area on the first surface where the insulating member is formed, and the insulating member is formed on the hole wall of the pole hole and the area surrounding the pole hole on the first surface of the top cover by a nano injection molding process.

[0014] The top cover assembly provided in this embodiment forms nano-scale micropores on the hole wall of the pole hole of the top cover and the area surrounding the pole hole on the first surface; a first insulating oxide layer is formed on the area of ​​the first surface of the top cover that is not covered by the insulating member; after the first insulating oxide layer is formed, an insulating member is formed on the area where the nano-scale micropores are formed through an injection molding process, thereby improving the bonding strength between the insulating member and the top cover.

[0015] According to one embodiment of the present application, the top cover assembly further includes:

[0016] The adapter plate is located on the side of the insulating member away from the top cover and is connected to the pole; the distance between the edge of the projection of the adapter plate on the top cover and the edge of the projection of the insulating member on the top cover is a, and a≤5mm.

[0017] The top cover assembly provided in the present embodiment has a first insulating oxide layer formed on the top cover. Therefore, the distance between the edge of the orthographic projection of the adapter plate on the top cover and the edge of the orthographic projection of the insulating member on the top cover can be ≤5mm, so that the shape and size of the adapter plate and the insulating member correspond to each other, thereby achieving insulation between the adapter plate and the top cover, avoiding the insulating member being too large, and avoiding the formation of bumps on the insulating member, so that when the battery cell produces gas due to thermal runaway, the gas can be discharged from the explosion-proof valve of the top cover in time, reducing the risk of explosion; at the same time, the area of ​​the insulating member is reduced, so that the area of ​​the top cover not covered by the insulating member can be directly exposed, so that the heat generated in the battery can be dissipated through the top cover more quickly, thereby improving the heat dissipation performance of the top cover assembly.

[0018] According to one embodiment of the present application, the orthographic projection of the adapter plate on the top cover completely overlaps with the orthographic projection of the insulating member on the top cover.

[0019] The top cover assembly provided in this embodiment makes the orthographic projection of the adapter on the top cover completely overlap with the orthographic projection of the insulating component on the top cover, that is, the shape and size of the adapter and the insulating component are completely consistent. The insulating component ensures the reliability of insulation between the adapter and the top cover, and at the same time avoids the insulating component being too large, so that when the battery cell thermally runs away and produces gas, the gas can be discharged from the explosion-proof valve of the top cover in time, reducing the risk of explosion.

[0020] According to one embodiment of the present application, the top cover assembly further includes:

[0021] An explosion-proof valve, wherein an explosion-proof hole is formed on the top cover, the explosion-proof valve is arranged on the explosion-proof hole, and the orthographic projection of the explosion-proof valve on the top cover has no overlapping part with the orthographic projection of the insulating member on the top cover; a second insulating oxide layer is formed on the surface of the explosion-proof valve facing the insulating member.

[0022] The top cover assembly provided in the present embodiment has no overlapping part between the orthographic projection of the explosion-proof valve on the top cover and the orthographic projection of the insulating member on the top cover, that is, the explosion-proof valve and the insulating member are staggered, and the explosion-proof valve is directly connected to the space between the top cover and the electrode assembly. When the electrode assembly produces gas due to thermal runaway, the gas will not be blocked by the insulating member and cannot reach the explosion-proof valve in time for discharge, thereby reducing the risk of explosion of the battery. At the same time, a second insulating oxide layer is formed on the surface of the explosion-proof valve facing the insulating member to form insulation between the explosion-proof valve and the electrode assembly.

[0023] According to an embodiment of the present application, the density of the first insulating oxide layer is greater than the density of the second insulating oxide layer.

[0024] The top cover assembly provided in this embodiment makes the density of the first insulating oxide layer greater than the density of the second insulating oxide layer, that is, the maximum surface tension of the second insulating oxide layer is smaller and is relatively easy to crack, thereby facilitating the opening of the explosion-proof valve, avoiding the situation in which the battery explodes due to the increase in the opening conditions of the explosion-proof valve caused by the provision of the second insulating oxide layer on the explosion-proof valve, thereby ensuring the reliability of the battery.

[0025] According to an embodiment of the present application, the top cover is made of the same material as the explosion-proof valve, and the first insulating oxide layer is made of the same material as the second insulating oxide layer.

[0026] In the top cover assembly provided in this embodiment, the insulating oxide layer formed on the top cover and the shell is made of the same material, so that the insulating oxide layer can be formed by the same oxidation process, which can reduce manufacturing costs and improve manufacturing efficiency.

[0027] According to an embodiment of the present application, an area of ​​the orthographic projection of the first insulating oxide layer on the first surface is 50% to 80% of the area of ​​the first surface.

[0028] In the top cover assembly provided in this embodiment, the shape and size of the adapter plate and the insulating member correspond, that is, the area on the first surface of the top cover not covered by the insulating member may be 50% to 80% of the area of ​​the first surface, that is, the area of ​​the insulating member is 20% to 50% of the area of ​​the first surface, thereby reducing the area of ​​the insulating member so that the area of ​​the top cover not covered by the insulating member can be directly exposed, so that the heat generated in the battery can be dissipated more quickly through the top cover, thereby improving the heat dissipation performance of the top cover assembly.

[0029] According to one embodiment of the present application, the top cover also includes a side wall connecting the first surface and the second surface, a step structure is formed on the side wall, the step structure includes a tread and a riser, the tread connects the riser and the second surface, and the riser connects the tread and the first surface; the first insulating oxide layer is not formed on the second surface, the tread and the riser, at least on the portion connected to the tread.

[0030] In the top cover assembly provided in this embodiment, the first insulating oxide layer is not formed on at least the portion of the tread and the riser of the top cover connected to the tread, so as to facilitate welding of the top cover and the shell.

[0031] According to an embodiment of the present application, the end of the pole located on the insulating member is flush with the surface of the insulating member away from the top cover.

[0032] The top cover assembly provided in this embodiment facilitates electrical connection between the adapter plate and the pole on the insulating member by making the end of the pole on the insulating member flush with the surface of the insulating member away from the top cover.

[0033] According to another aspect of the present application, a method for manufacturing a top cover assembly is provided, the manufacturing method comprising:

[0034] Providing a top cover, the top cover comprising a first surface and a second surface opposite to each other, and forming a pole hole on the top cover that passes through the first surface and the second surface;

[0035] The top cover is shielded to expose only a second area on the first surface other than the first area surrounding the pole hole;

[0036] forming a first insulating oxide layer on the second region of the first surface;

[0037] Inserting the pole into the pole hole;

[0038] An insulating member is formed between the hole wall of the pole hole and the outer peripheral surface of the pole, and on the first region of the first surface.

[0039] In the manufacturing method of the top cover assembly provided in the present embodiment, the insulating part located on the hole wall of the pole hole forms insulation between the pole and the top cover, and the insulating part located on the area surrounding the pole hole forms insulation between the top covers when the adapter is subsequently set; the thickness of the first insulating oxide layer formed is greatly reduced relative to the insulating part, so that the heat generated in the battery can be dissipated through the top cover more quickly, thereby improving the heat dissipation performance of the top cover assembly; in addition, by relatively reducing the area of ​​the insulating part, it is avoided that the insulating part forms a structure such as a bump that blocks the flow of gas, so that when the battery cell produces gas due to thermal runaway, the gas can be discharged from the explosion-proof valve of the top cover in time, reducing the risk of battery explosion and improving the safety of the battery.

[0040] According to an embodiment of the present application, after forming a pole hole penetrating the first surface and the second surface on the top cover and before shielding the top cover, the manufacturing method further includes:

[0041] Forming nanoscale micropores on the hole wall of the pole hole and on a first region surrounding the pole hole on the first surface;

[0042] Wherein, an insulating member is formed between the hole wall of the pole hole and the outer peripheral surface of the pole, and on the first region where the nanoscale micropores are formed, by nano injection molding process.

[0043] The manufacturing method of the top cover assembly provided in the present embodiment first forms nano-scale micropores on the hole wall of the pole hole of the top cover and the area surrounding the pole hole on the first surface; then, by shielding the top cover, only the second area outside the first area on the first surface is exposed; then, a first insulating oxide layer is formed on the area of ​​the first surface of the top cover that is not covered by the insulating member; after the first insulating oxide layer is formed, an insulating member is then formed on the area where the nano-scale micropores are formed, that is, the hole wall of the pole hole and the area surrounding the pole hole on the first surface, through an injection molding process, thereby improving the bonding strength between the insulating member and the top cover.

[0044] According to another aspect of the present application, there is provided an energy storage device, the energy storage device comprising:

[0045] A shell, wherein the shell is formed with a receiving space having an opening, and a third insulating oxide layer is formed on the inner wall of the shell;

[0046] an electrode assembly, wherein the electrode assembly is disposed in the accommodation space, and the electrode assembly directly abuts against the third insulating oxide layer formed on the inner wall of the shell or has a gap therebetween, and the gap only has gas and / or electrolyte;

[0047] The top cover assembly mentioned above covers the opening, and the electrode assembly is electrically connected to the pole.

[0048] In the energy storage device provided by this embodiment, the insulating member located on the hole wall of the pole hole forms insulation between the pole and the top cover, and the insulating member located in the area surrounding the pole hole forms insulation between the top covers when the adapter is subsequently set; on the first surface of the top cover, the insulating member is only located in the area surrounding the pole hole and does not completely cover the first surface of the top cover; insulation is formed by setting a first insulating oxide layer on the area of ​​the first surface of the top cover that is not covered by the insulating member, and the thickness of the first insulating oxide layer is greatly reduced relative to the insulating member, so that the heat generated in the battery can be dissipated through the top cover more quickly, thereby improving the heat dissipation performance of the top cover assembly; in addition, by relatively reducing the area of ​​the insulating member, it is avoided that the insulating member forms a structure such as a bump that blocks the flow of gas, so that when the battery cell produces gas due to thermal runaway, the gas can be discharged from the explosion-proof valve of the top cover in time, thereby reducing the risk of battery explosion and improving the safety of the energy storage device.

[0049] According to another aspect of the present application, an electric device is provided, characterized in that the electric device includes the above-mentioned energy storage device, and the energy storage device supplies power to the electric device.

[0050] In the electrical equipment provided in the present embodiment, in the energy storage device and the top cover assembly, the insulating member located on the hole wall of the pole hole forms insulation between the pole and the top cover, and the insulating member located in the area surrounding the pole hole forms insulation between the top covers when the adapter is subsequently set; on the first surface of the top cover, the insulating member is only located in the area surrounding the pole hole, and does not completely cover the first surface of the top cover; insulation is formed by setting a first insulating oxide layer on the area of ​​the first surface of the top cover that is not covered by the insulating member, and the thickness of the first insulating oxide layer is greatly reduced relative to the insulating member, so that the heat generated in the battery can be dissipated through the top cover more quickly, thereby improving the heat dissipation performance of the top cover assembly; in addition, by relatively reducing the area of ​​the insulating member, it is avoided that the insulating member forms a structure such as a bump that blocks the flow of gas, so that when the battery cell produces gas due to thermal runaway, the gas can be discharged from the explosion-proof valve of the top cover in time, thereby reducing the risk of battery explosion and improving the safety of the electrical equipment.

[0051] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The above and other features and advantages of the present application will become more apparent by describing in detail example embodiments thereof with reference to the attached drawings.

[0053] Figure 1 A schematic diagram of a household energy storage system provided for one embodiment of the present application;

[0054] Figure 2 A schematic diagram of the structure of a single cell provided in one embodiment of the present application;

[0055] Figure 3 An exploded view of the structure of a single cell provided in one embodiment of the present application;

[0056] Figure 4 An exploded view of the structure of a single cell provided in one embodiment of the present application from another perspective;

[0057] Figure 5 A schematic diagram of the structure of an injection molded part provided in one embodiment of the present application;

[0058] Figure 6 A schematic structural diagram of an injection molded part from another perspective provided in one embodiment of the present application;

[0059] Figure 7 A schematic diagram of a first side of a top cover assembly provided for one embodiment of the present application;

[0060] Figure 8 A schematic diagram of a housing provided for one embodiment of the present application;

[0061] Fig. 9 A flow chart of a method for manufacturing a top cover assembly provided for one embodiment of the present application.

[0062] Description of reference numerals:

[0063] 1. Energy storage device; 2. Electric energy conversion device; 3. User load;

[0064] 10. Single battery;

[0065] 100, housing; 110, opening;

[0066] 200, electrode assembly; 210, battery cell; 220, positive electrode ear; 230, negative electrode ear;

[0067] 300, top cover assembly; 310, top cover; 320, pole; 321, positive pole; 322, negative pole; 330, insulating member; 331, positive insulating member; 332, negative insulating member; 340, explosion-proof valve; 350, injection hole; 360, adapter; 361, positive adapter; 362, negative adapter;

[0068] 410, a first insulating oxide layer; 420, a second insulating oxide layer; 430, a third insulating oxide layer. DETAILED DESCRIPTION

[0069] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted.

[0070] Since the energy people need is highly temporal and spatial, in order to rationally use energy and improve energy utilization, it is necessary to use a medium or device to store one form of energy in the same form or convert it into another form of energy, and then release it in a specific form of energy based on future application needs. As we all know, the purpose of generating green electricity is currently mainly achieved by replacing fossil energy with green energy.

[0071] The current green energy mainly includes solar energy, wind energy, hydropower, etc. However, solar energy and wind energy generally have problems of strong intermittency and large volatility, which will cause unstable voltage of the green power grid (not enough electricity during peak hours and too much electricity during low hours). Unstable voltage will cause damage to electricity. Therefore, it may cause the problem of "wind and solar power abandonment" due to insufficient electricity demand or insufficient grid acceptance capacity.

[0072] To solve the problem of insufficient electricity demand or insufficient grid acceptance capacity, we must rely on energy storage devices. That is, the energy storage device converts electrical energy into other forms of energy through physical or chemical means and stores it, and then converts the energy stored in the energy storage device into electrical energy when needed. In simple terms, the energy storage device is similar to a large "power bank", which stores electrical energy when there is sufficient light energy and wind energy, and releases the stored electrical energy when needed.

[0073] At present, energy storage (i.e. energy storage) has a wide range of application scenarios, including power generation side energy storage, grid side energy storage, renewable energy grid-connected energy storage and user side energy storage. The corresponding types of energy storage devices include:

[0074] (1) Large energy storage containers used in grid-side energy storage scenarios can serve as high-quality active and reactive power regulation power sources in the grid, achieve load matching of electric energy in time and space, enhance the ability to absorb renewable energy, and are of great significance in grid system backup, relieving peak load power supply pressure, and peak and frequency regulation;

[0075] (2) The main operating mode of small and medium-sized energy storage cabinets used in industrial and commercial energy storage scenarios (banks, shopping malls, etc.) on the user side and small household energy storage boxes used in home energy storage scenarios on the user side is "peak shaving and valley filling". Since there is a large price difference in electricity charges at peak and valley locations according to electricity demand, after users have energy storage equipment, in order to reduce costs, they usually charge the energy storage cabinets / boxes during the low electricity price period; during the peak electricity price period, the electricity in the energy storage equipment is discharged for use to achieve the purpose of saving electricity bills. In addition, in remote areas and areas prone to natural disasters such as earthquakes and hurricanes, the existence of household energy storage devices is equivalent to users providing themselves and the power grid with backup power, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0076] Take the household energy storage scenario in user-side energy storage as an example to illustrate. Figure 1 A household energy storage system is shown, which includes an energy storage device 1 and an electric energy conversion device 2 (such as a photovoltaic panel), and a user load 3 (such as a street lamp, household appliances, etc.). The energy storage device 1 is a small energy storage box that can be mounted on an outdoor wall by wall hanging. Specifically, the electric energy conversion device 2 can convert solar energy into electric energy during the period of low electricity prices, and store it through the energy storage device 1, and then supply the user load 3 for use during the peak electricity price, or supply the user load 3 for use when the power grid is out of power / power outage.

[0077] In combination with the above-mentioned situation of storing energy by physical or electrochemical means, taking electrochemical energy storage as an example, the energy storage device 1 includes at least one chemical battery, using the chemical elements in the chemical battery as the energy storage medium, so as to realize the charging and discharging process through the chemical reaction or change of the energy storage medium. In simple terms, the electric energy generated by light energy and wind energy is stored in at least one group of chemical batteries through the chemical reaction or change of the energy storage medium, and when the use of external electric energy reaches a peak, the electric energy stored in at least one group of chemical batteries is released for use through the chemical reaction or change of the energy storage medium, or transferred to a place where the electric energy is scarce for use.

[0078] In the related art, when the battery cell generates heat during charging and discharging, the heat needs to pass through the lower plastic and aluminum cover of the top cover assembly. The heat transfer path is long and the heat dissipation is slow, which may cause the battery cell to be overheated and cause thermal runaway.

[0079] In view of the above technical problems, the embodiments of the present application provide an energy storage device, which may be, but is not limited to, a single cell, a battery module, a battery pack, a battery system, etc. As for the single cell, it may be a lithium-ion secondary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, a magnesium-ion battery, etc. The single cell may be cylindrical, flat, rectangular, etc., and the embodiments of the present application do not limit this.

[0080] Next, taking the energy storage device as a square single battery as an example, the specific details of the energy storage device are explained in detail.

[0081] Figure 2 The schematic diagram of the structure of a single cell provided by the embodiment of the present application is illustrated. Figure 2 As shown, the single battery 10 includes: a shell 100 , an electrode assembly 200 and a top cover assembly 300 . The shell 100 is formed with a receiving space having an opening 110 , and the top cover assembly 300 covers the opening 110 of the shell 100 .

[0082] In one embodiment, Figure 4 and Figure 7 As shown, the top cover assembly 300 includes a top cover 310, a pole 320, an insulating member 330 and a first insulating oxide layer 410, the top cover 310 includes a first surface and a second surface opposite to each other, and a pole hole penetrating the first surface and the second surface is formed on the top cover 310; the pole 320 is inserted into the pole hole; the insulating member 330 is formed on the hole wall of the pole hole and is located between the hole wall and the outer peripheral surface of the pole 320, as well as on the area surrounding the pole hole on the first surface of the top cover 310, that is, the insulating member 330 and the top cover 310 are stacked in the thickness direction Z; a first insulating oxide layer 410 is formed on the first surface of the top cover 310, and the first insulating oxide layer 410 is formed on the area of ​​the first surface of the top cover 310 that is not covered by the insulating member 330.

[0083] The top cover assembly 300 provided by the present application has an insulating member 330 located on the hole wall of the pole hole to form insulation between the pole 320 and the top cover 310, and an insulating member 330 located in the area surrounding the pole hole to form insulation between the top cover 310 when the adapter is subsequently set; on the first surface of the top cover 310, the insulating member 330 is only located in the area surrounding the pole hole and does not completely cover the first surface of the top cover 310; the area on the first surface of the top cover 310 not covered by the insulating member 330 is formed by setting a first insulating oxide layer 410 Insulation is achieved, and the thickness of the first insulating oxide layer 410 is greatly reduced relative to the insulating member 330, so that the heat generated in the battery can be dissipated more quickly through the top cover 310, thereby improving the heat dissipation performance of the top cover assembly 300; in addition, by relatively reducing the area of ​​the insulating member 330, it is avoided that the insulating member 330 forms a structure such as a bump that blocks the flow of gas, so that when the battery cell 210 produces gas due to thermal runaway, the gas can be discharged from the explosion-proof valve of the top cover 310 in time, reducing the risk of battery explosion and improving the safety of the battery.

[0084] In one embodiment, nano-scale micropores are formed on the hole wall of the pole hole and the area on the first surface where the insulating member 330 is formed, and the insulating member 330 is formed on the hole wall of the pole hole and the area surrounding the pole hole on the first surface of the top cover 310 by a nano injection molding process. By forming nano-scale micropores on the hole wall of the pole hole of the top cover 310 and the area surrounding the pole hole on the first surface, the insulating member 330 is formed on the area where the nano-scale micropores are preset, that is, the hole wall of the pole hole and the area surrounding the pole hole on the first surface by an injection molding process, thereby improving the bonding strength between the insulating member 330 and the top cover 310.

[0085] Among them, nano injection molding refers to nano molding technology, which is a process of combining metal and plastic with nano technology. The surface of the metal cover 300 can be nano-processed, and the insulating part 330 of the plastic material can be directly injection molded on the surface of the metal cover 300, so that the metal and plastic can be integrally molded, and finally the cover 300 and the insulating part 330 are combined into a product.

[0086] Among them, the nano-scale micropores on the top cover 300 can be processed by nano-scale microporation on the surface of the metal top cover 300 through a chemical solution, so that the surface of the metal top cover 300 and the insulating part 330 of the plastic material can be better combined, thereby improving the connection strength, so as to overcome the problem of reduced connection strength caused by reducing the contact area between the insulating part 330 and the top cover 300 due to reducing the size of the insulating part 330, thereby ensuring the connection strength and reliability between the insulating part 330 and the top cover 300.

[0087] In one embodiment, the top cover assembly 300 also includes a transfer plate 360, which is located on the side of the insulating member 330 away from the top cover 310 and is connected to the pole 320; the insulating member 330 forms insulation between the transfer plate 360 ​​and the top cover 310, and the electrode assembly 200 is electrically connected to the pole 320 through the transfer plate 360.

[0088] The distance between the edge of the orthographic projection of the adapter sheet 360 on the top cover 310 and the edge of the orthographic projection of the insulating member 330 on the top cover 310 is a, and a≤5mm, for example, 5mm, 4mm, 3mm, 2mm, 1mm, 0, etc. It should be noted that the edge of the orthographic projection of the adapter sheet 360 on the top cover 310 and the edge of the orthographic projection of the insulating member 330 on the top cover 310 here refer to the outer edge of the adapter sheet 360 and the outer edge of the insulating member 330. By making the distance between the edge of the orthographic projection of the adapter sheet 360 on the top cover 310 and the edge of the orthographic projection of the insulating member 330 on the top cover 310 ≤5mm, the shapes and sizes of the adapter sheet 360 and the insulating member 330 correspond to each other, thereby achieving insulation between the adapter sheet 360 and the top cover 310, avoiding the insulating member 330 from being too large, and avoiding the insulating member 330 from having bumps, so that when the battery cell 210 produces gas due to thermal runaway, the gas can be discharged from the explosion-proof valve of the top cover 310 in time, reducing the risk of explosion; at the same time, the area of ​​the insulating member 330 is reduced, so that the area of ​​the top cover 310 not covered by the insulating member 330 can be directly exposed, so that the heat generated in the battery can be dissipated more quickly through the top cover 310, thereby improving the heat dissipation performance of the top cover assembly 300.

[0089] In one embodiment, the first insulating oxide layer 410 may be an insulating oxide layer formed by a redox reaction of electroplating. For example, the insulating oxide layer may be formed by electroplating and depositing on the area of ​​the first surface of the top cover 310 that is not covered by the insulating member 330 by vapor deposition; or, the insulating oxide layer may be formed by electrophoresis by a redox reaction of electroplating. For example, the insulating oxide layer may be formed by electroplating and depositing on the area of ​​the first surface of the top cover 310 that is not covered by the insulating member 330 by vapor deposition.

[0090] In another embodiment, the first insulating oxide layer 410 may be an insulating oxide layer formed by an oxidation reaction on the metal surface. This process is mainly carried out by exposing the metal to an environment of oxygen or an oxidant to generate an oxide. The principle of oxidation treatment mainly includes two aspects: one is oxidation reaction, that is, the metal reacts chemically with oxygen to generate an oxide; the other is the formation and stability of the oxide, that is, the oxide forms a dense oxide film on the metal surface, which plays an insulating and protective role. Among them, the oxidation treatment methods include: 1. Thermal oxidation method: heating the metal to a certain temperature so that it reacts with oxygen to generate an oxide; this method is suitable for oxidation treatment at high temperature, such as hot immersion method, hot pressing method and thermal oxidation method; 2. Chemical oxidation method: by immersing the metal in a chemical solution with an oxidant, oxidation treatment under the condition, such as anodization method and chemical oxidation method; 3. Electrochemical oxidation method: by applying an electric current in the electrolyte, such as anodization method and electrochemical oxidation method.

[0091] When the top cover 310 is oxidized, a sacrificial layer may be used to cover all areas of the top cover 310 except the first surface, leaving only the area of ​​the first surface not covered by the insulating member 330 exposed for oxidation.

[0092] The top cover 310 is usually an aluminum cover plate, and the surface of the aluminum cover plate is oxidized to form a dense insulating oxide film as the first insulating oxide layer 410. Of course, the top cover 310 can also be other metal materials, and the present application does not limit this. It can form a dense insulating oxide film through an oxidation reaction on its surface. The surface of the top cover 310 is oxidized to form a dense insulating oxide film. The insulating oxide film is a modified layer formed on the surface of the top cover 310, that is, no additional other hierarchical structures are formed on the surface of the top cover 310, which further reduces the thickness of the area on the first surface of the top cover 310 that is not covered by the insulating member 330, thereby further improving the heat dissipation capacity of the top cover 310.

[0093] In one embodiment, the area of ​​the orthographic projection of the first insulating oxide layer 410 on the first surface is 50% to 80% of the area of ​​the first surface, for example 50%, 55%, 60%, 65%, 70%, 75%, 80%, etc.; the adapter plate 360 ​​corresponds to the shape and size of the insulating member 330, that is, the area on the first surface of the top cover 310 not covered by the insulating member 330 may be 50% to 80% of the area of ​​the first surface, that is, the area of ​​the insulating member 330 is 20% to 50% of the area of ​​the first surface, which reduces the area of ​​the insulating member 330, so that the area of ​​the top cover 310 not covered by the insulating member 330 can be directly exposed, so that the heat generated in the battery can be dissipated more quickly through the top cover 310, thereby improving the heat dissipation performance of the top cover assembly 300.

[0094] Specifically, Figure 3As shown, the electrode assembly 200 includes a plurality of tabs, including at least one positive tab 220 and at least one negative tab 230; the single battery 10 includes a plurality of adapters 360, including at least one positive adapter 361 and at least one negative adapter 362; the single battery 10 includes a plurality of poles 320, including at least one positive pole 321 and at least one negative pole 322. The positive adapter 361 is connected to the positive tab 220, and the negative adapter 362 is connected to the negative tab 230; the positive pole 321 is connected to the positive adapter 361, and the negative pole 322 is connected to the negative adapter 362.

[0095] Among them, Figure 4 As shown, the pole 320 includes a positive pole 321 and a negative pole 322, the adapter 360 includes a positive adapter 361 and a negative adapter 362, and the insulating member 330 includes a positive insulating member 331 and a negative insulating member 332. The positive insulating member 331 is located between the positive adapter 361 and the top cover 310 to achieve insulation between the positive adapter 361 and the top cover 310; the negative insulating member 332 is located between the negative adapter 362 and the top cover 310 to achieve insulation between the negative adapter 362 and the top cover 310.

[0096] Among them, the positive ear 220 of the battery cell 210 is electrically connected to the positive pole 321 through the positive adapter 361, and the distance between the edge of the positive projection of the positive adapter 361 on the top cover 310 and the edge of the positive projection of the positive insulating member 331 on the top cover 310 is a, a≤5mm, for example, 5mm, 4mm, 3mm, 2mm, 1mm, 0mm, etc. In the width direction X and the length direction Y of the top cover 310, the edge of the positive adapter 361 and the edge protruding from the positive insulating member 331, or the edge of the positive insulating member 331 and the edge protruding from the positive adapter 361.

[0097] The negative ear 230 of the battery cell 210 is electrically connected to the negative pole 322 through the negative electrode adapter 362. The distance between the edge of the negative projection of the negative electrode adapter 362 on the top cover 310 and the edge of the negative projection of the negative electrode insulating member 332 on the top cover 310 is a, a≤5mm, for example, 5mm, 4mm, 3mm, 2mm, 1mm, 0mm, etc. In the width direction X and the length direction Y of the top cover 310, the edge of the negative electrode adapter 362 and the edge protruding from the negative electrode insulating member 332, or the edge of the negative electrode insulating member 332 and the edge protruding from the negative electrode adapter 362.

[0098] In one embodiment, the orthographic projection of the adapter 360 on the top cover 310 completely overlaps with the orthographic projection of the insulating member 330 on the top cover 310. By making the orthographic projection of the adapter 360 on the top cover 310 completely overlap with the orthographic projection of the insulating member 330 on the top cover 310, that is, the shape and size of the adapter 360 and the insulating member 330 are completely consistent, the insulating member 330 ensures the reliability of the insulation between the adapter 360 and the top cover 310, and at the same time avoids the insulating member 330 from being too large, so that when the battery cell 210 produces gas due to thermal runaway, the gas can be discharged from the explosion-proof valve of the top cover 310 in time, reducing the risk of explosion.

[0099] Among them, Figures 4 to 6 As shown, the positive projection of the positive electrode adapter 361 on the top cover 310 completely overlaps with the positive electrode insulating member 331 on the top cover 310, and the negative electrode adapter 362 on the top cover 310 completely overlaps with the negative electrode insulating member 332 on the top cover 310, so that the top cover 310 and the electrode assembly 200 except the positive electrode insulating member 331 and the negative electrode insulating member 332 can form an exhaust and heat dissipation path, thereby improving the heat dissipation effect; at the same time, the gas produced by the battery cell 210 can be gathered at the top cover 310, so that the valve can be opened in time to exhaust when the gas pressure is high, reducing the risk of explosion and improving the reliability of the battery. In addition, by reducing the insulating member 330 to the same size as the adapter 360, the weight of the insulating member 330 is reduced, thereby reducing the weight of the single battery 10. When multiple single batteries 10 are grouped, the total weight of the multiple single batteries 10 after grouping can be reduced, thereby reducing the weight of the energy storage device, achieving lightweight and improving the market competitiveness of the product.

[0100] Of course, the orthographic projection of the positive electrode adapter 361 on the top cover 310 may completely overlap with the orthographic projection of the positive electrode insulating member 331 on the top cover 310, and the orthographic projection of the negative electrode adapter 362 on the top cover 310 may not completely overlap with the orthographic projection of the negative electrode insulating member 332 on the top cover 310; or, the orthographic projection of the positive electrode adapter 361 on the top cover 310 may not completely overlap with the orthographic projection of the positive electrode insulating member 331 on the top cover 310, and the orthographic projection of the negative electrode adapter 362 on the top cover 310 may completely overlap with the orthographic projection of the negative electrode insulating member 332 on the top cover 310, and the present application does not impose any restrictions on this.

[0101] In one embodiment, Figure 3 to Figure 6As shown, a depression of a positive pole column 321 is formed on the positive insulator 331, and the positive pole column 321 includes a fixing portion located in the depression; the depression is rectangular, so as to form an assembly position of the positive pole column 321 and the positive insulator 331 in the width direction X and the length direction Y, so as to realize the rapid assembly of the positive pole column 321 and the positive insulator 331, and to improve the assembly accuracy. A depression of a negative pole column 322 is formed on the negative insulator 332, and the negative pole column 322 includes a fixing portion located in the depression; the depression is rectangular, so as to form an assembly position of the negative pole column 322 and the negative insulator 332 in the width direction X and the length direction Y, so as to realize the rapid assembly of the negative pole column 322 and the negative insulator 332, and to improve the assembly accuracy.

[0102] In one embodiment, Figure 7 As shown, the end of the pole 320 located on the insulating member 330 is flush with the surface of the insulating member 330 away from the top cover 310, and the shape of the end of the pole 320 matches the shape of the pole hole formed on the insulating member 330. By making the end of the pole 320 located on the insulating member 330 flush with the surface of the insulating member 330 away from the top cover 310, it is convenient for the adapter 360 to be electrically connected to the pole 320 on the insulating member 330. Of course, the end of the pole 320 located on the insulating member 330 can be protruding from the surface of the insulating member 330 away from the top cover 310, and the present application does not limit this.

[0103] Among them, when the insulating part 330 is formed on the top cover 310 by injection molding, the pole 320 can be preset in the pole hole of the top cover 310, and there is a gap between the pole 320 and the hole wall of the pole hole of the top cover 310; then the insulating part material is formed on the first surface of the top cover 310, the hole wall of the pole hole and the outer peripheral surface of the pole 320 by the injection molding process, and finally the insulating part 330 is formed.

[0104] When the insulating member 330 is formed on the outer peripheral surface of the pole 320 by injection molding, nanoscale micropores can be formed on the outer peripheral surface of the pole 320 to enhance the bonding force between the insulating member 330 and the outer peripheral surface of the pole 320 , thereby enhancing the connection strength between the insulating member 330 and the pole 320 .

[0105] During the injection molding, the injection molding process can be controlled so that the end of the pole 320 located on the insulating member 330 is flush with the surface of the insulating member 330 away from the top cover 310 .

[0106] In one embodiment, Figure 3As shown, the electrode assembly 200 includes two battery cells 210, the positive electrode adapter plate 361 includes two positive electrode connecting parts, and the negative electrode adapter plate 362 includes two negative electrode connecting parts; the positive electrode ears 220 of the two battery cells 210 are respectively connected to the positive electrode connecting parts of the positive electrode adapter plate 361, and the negative electrode ears 230 of the two battery cells 210 are respectively connected to the two negative electrode connecting parts on the negative electrode adapter plate 362.

[0107] In one embodiment, Figure 2 to Figure 4 and Figure 7 As shown, the top cover assembly 300 further includes: an explosion-proof valve 340, which is disposed on the top cover 310. A second insulating oxide layer 420 is formed on the surface of the explosion-proof valve 340 facing the insulating member 330, so as to insulate the explosion-proof valve 340 from the electrode assembly 200.

[0108] Among them, an explosion-proof hole can be set on the top cover assembly 300, and the explosion-proof valve 340 can be installed on the explosion-proof hole by welding or the like; or, a notch can be formed on the top cover 310, and the part surrounded by the notch can be used as the explosion-proof valve 340; when the gas pressure inside the single battery 10 is greater than the set critical value, the explosion-proof valve 340 opens to exhaust gas to avoid explosion caused by excessive gas pressure inside the battery.

[0109] When the explosion-proof valve 340 is provided in the explosion-proof hole by welding or the like, the second insulating oxide layer 420 may be formed on the surface of the explosion-proof valve 340 facing the insulating member 330 before the explosion-proof valve 340 is welded; or, after the explosion-proof valve 340 is welded, the second insulating oxide layer 420 may be formed on the surface of the explosion-proof valve 340 facing the insulating member 330 by the same process as the top cover 310, and the second insulating oxide layer 420 is the same insulating oxide layer as the first insulating oxide layer 410. When a notch is formed on the top cover 310 and the portion surrounded by the notch is used as the explosion-proof valve 340, the second insulating oxide layer 420 may be formed on the surface of the explosion-proof valve 340 facing the insulating member 330 by the same process as the top cover 310, and the second insulating oxide layer 420 is the same insulating oxide layer as the first insulating oxide layer 410.

[0110] Among them, by forming a notch on the top cover 310, when the portion surrounded by the notch is used as the explosion-proof valve 340, the material of the explosion-proof valve 340 is the same as the material of the top cover 310, and the second insulating oxide layer 420 is the same as the material of the first insulating oxide layer 410, thereby reducing the process cost and improving the process efficiency.

[0111] Among them, Figure 4As shown, the orthographic projection of the explosion-proof valve 340 on the top cover 310 has no overlapping part with the orthographic projection of the insulating member 330 on the top cover 310. By making the orthographic projection of the explosion-proof valve 340 on the top cover 310 and the orthographic projection of the insulating member 330 on the top cover 310 have no overlapping part, that is, the explosion-proof valve 340 and the insulating member 330 are staggered, the explosion-proof valve 340 is directly connected to the space between the top cover 310 and the electrode assembly 200. When the electrode assembly 200 produces gas due to thermal runaway, the gas will not be blocked by the insulating member 330 and cannot reach the explosion-proof valve 340 in time for discharge, thereby reducing the risk of battery explosion.

[0112] Among them, the density of the first insulating oxide layer 410 on the first surface of the top cover 310 is greater than the density of the second insulating oxide layer 420 on the explosion-proof valve 340, that is, the density of the formed second insulating oxide layer 420 is relatively small, and the maximum tension of the second insulating oxide layer 420 is relatively small, that is, it is relatively easy to crack, thereby facilitating the opening of the explosion-proof valve 340, avoiding the situation where the opening conditions of the explosion-proof valve 340 are increased due to the provision of the second insulating oxide layer 420 on the explosion-proof valve 340, resulting in the gas produced by the battery cannot be discharged in time and explosion occurs, thereby ensuring the reliability of the battery.

[0113] In one embodiment, Figure 3 and Figure 4 As shown, the housing 100 is provided with an injection hole 350, and the injection hole 350 is located between the positive electrode column 321 and the negative electrode column 322. The electrolyte is injected into the battery cell 210 through the injection hole 350, and the electrolyte can evenly infiltrate the battery cell 210 to ensure the infiltration efficiency of the electrolyte. Among them, a sealing plug is provided on the injection hole 350 to block the injection hole 350 after the electrolyte is added.

[0114] In one embodiment, Figure 8As shown, the shell 100 is made of metal, and a third insulating oxide layer 430 is formed on the inner surface of the shell 100 ; the electrode assembly 200 is disposed in the accommodating space, and the electrode assembly 200 is insulated from the shell 100 by the third insulating oxide layer 430 . In the single cell battery 10 provided in the present application, the electrode assembly 200 is arranged in the accommodating space, and a third insulating oxide layer 430 is formed on the inner surface of the shell 100. The electrode assembly 200 is insulated from the shell 100 by the third insulating oxide layer 430, that is, the insulation of the electrode assembly 200 and the shell 100 is directly realized, avoiding the arrangement of other insulating structural parts between the shell 100 and the electrode assembly 200, so that the heat generated by the electrode assembly 200 can be directly dissipated through the shell 100, the heat transfer path is short, and the heat dissipation is fast, avoiding the problem of thermal runaway of the electrode assembly 200 caused by excessive temperature of the electrode assembly 200; at the same time, when the electrode assembly 200 produces gas due to thermal runaway, the gas will not be unable to reach the top cover 310 in time for discharge due to the obstruction of other insulating structural parts arranged between the shell 100 and the electrode assembly 200, thereby reducing the risk of battery explosion.

[0115] Among them, Figure 2 As shown, the single battery 10 is a square battery, that is, the single battery 10 can be a quadrangular prism battery, which is convenient for grouping. A quadrangular prism battery refers to a battery with a prism shape, but it is not strictly limited whether each side of the prism must be a straight line in the strict sense, and the corners between the sides are right angles, rounded corners or chamfered corners.

[0116] Among them, Figure 2 As shown, the housing 100 and the top cover assembly 300 cooperate to form a quadrangular prism-shaped housing, and the square battery includes an electrode assembly 200 and an electrolyte located in the housing 100. The electrode assembly 200 includes a battery cell 210, a positive electrode tab 220, and a negative electrode tab 230. The battery cell 210 has a positive electrode sheet, a negative electrode sheet, and a diaphragm sheet disposed between the positive electrode sheet and the negative electrode sheet stacked on each other. The positive electrode sheet and the negative electrode sheet and the diaphragm sheet disposed between the positive electrode sheet and the negative electrode sheet are wound to obtain a wound battery cell 210. Optionally, the battery cell 210 may be a stacked laminated battery cell 210.

[0117] In one embodiment, the electrode assembly 200 directly abuts against the inner wall of the shell 100 or there is a gap between the electrode assembly 200 and the inner wall of the shell 100, and there is only gas and / or electrolyte in the gap. A third insulating oxide layer 430 is formed on the inner wall of the shell 100, and the electrode assembly 200 is directly in contact with the inner wall of the shell 100 or there is only gas and / or electrolyte in the gap between the electrode assembly 200 and the inner wall of the shell 100. The insulation between the electrode assembly 200 and the inner wall of the shell 100 is achieved by the third insulating oxide layer 430, that is, no other insulating components are required between the electrode assembly 200 and the inner wall of the shell 100, so that the heat generated by the electrode assembly 200 can be directly dissipated through the side wall of the shell 100, the heat transfer path is short, and the heat dissipation is fast, thereby avoiding the problem of thermal runaway of the battery cell 210 caused by excessive temperature of the battery cell 210; at the same time, when the electrode assembly 200 produces gas due to thermal runaway, the gas will not be unable to reach the top cover 310 in time and be discharged through the explosion-proof valve due to the obstruction of other insulating structural components set between the side wall of the shell 100 and the side of the electrode assembly 200, thereby reducing the risk of explosion. In addition, it is avoided to set other insulating structural parts between the inner wall of the shell 100 and the electrode assembly 200, which reduces the weight of the shell 100 and thus reduces the weight of the single cell 10. When multiple single cells 10 are grouped, the total weight of the multiple single cells 10 after grouping can be reduced, thereby reducing the weight of the energy storage device and achieving lightweight.

[0118] In one embodiment, one end of the electrode assembly 200 away from the top cover assembly 300 directly abuts against the bottom surface of the shell 100. A third insulating oxide layer 430 is formed on the bottom surface of the shell 100, and one end of the electrode assembly 200 away from the top cover assembly 300 directly abuts against the bottom of the shell 100. The third insulating oxide layer 430 realizes the insulation between the bottom of the electrode assembly 200 and the bottom of the shell 100, and no other insulating components, such as a bottom support plate, are required, so that the heat generated by the electrode assembly 200 can be directly dissipated through the bottom of the shell 100, the heat transfer path is short, the heat dissipation is fast, and the problem of thermal runaway of the battery cell 210 caused by excessive temperature of the battery cell 210 is avoided; at the same time, when the electrode assembly 200 produces gas due to thermal runaway, the gas will not be blocked by other insulating structural components between the bottom of the shell 100 and the bottom of the electrode assembly 200 and cannot reach the top cover 310 in time and be discharged through the explosion-proof valve, thereby reducing the risk of explosion. In addition, it is avoided to set other insulating structural parts between the shell 100 and the electrode assembly 200, which reduces the weight of the shell 100 and thus reduces the weight of the single cell 10. When a plurality of single cells 10 are grouped, the total weight of the grouped plurality of single cells 10 can be reduced, thereby reducing the weight of the energy storage device and achieving lightweight.

[0119] In one embodiment, the top cover 310 and the housing 100 are made of the same material, and the insulating oxide layers formed on the top cover 310 and the housing 100 are the same, so that the insulating oxide layers can be formed by the same oxidation process, which can reduce manufacturing costs and improve manufacturing efficiency. Of course, the top cover 310 and the housing 100 can also be made of different materials, and the insulating oxide layers formed on the top cover 310 and the housing 100 can also be different, and this application does not limit this.

[0120] The material of the top cover 310 and the shell 100 can be, for example, aluminum alloy. Aluminum alloy has low density, high strength, good plasticity, can be processed into various profiles, and has excellent thermal conductivity and corrosion resistance. An aluminum oxide film can be formed on the surface of the aluminum alloy through an anodizing process, and the formed aluminum oxide film is used as an insulating oxide layer. Of course, those skilled in the art can also use other technical materials as the top cover 310 and the shell 100, and form an insulating oxide film through a corresponding oxidation process, and this application does not limit this. Any changes in the metal material of the top cover 310 and the shell 100 are within the protection scope of this application.

[0121] The third insulating oxide layer 430 on the surface of the shell 100 may be formed in the same manner as the first insulating oxide layer 410 , and the material of the third insulating oxide layer 430 may be the same as the material of the first insulating oxide layer 410 , which is not limited in the present application.

[0122] In one embodiment, the top cover 310 further includes a side wall connecting the first surface and the second surface, and no insulating oxide layer is formed on the second surface and the side wall, so as to facilitate welding of the top cover 310 and the housing 100 .

[0123] Among them, a step structure is formed on the side wall of the top cover 310, and the step structure includes a tread and a riser, the tread connects the riser and the second surface, and the riser connects the tread and the first surface; because the first insulating oxide layer 410 is formed on the area of ​​the first surface of the top cover 310 that is not covered by the insulating member 330, due to process reasons, the first insulating oxide layer 410 may be formed on the portion of the riser connected to the first surface, so the first insulating oxide layer 410 is not formed on the second surface, the tread and the riser, at least on the portion connected to the tread, so as to ensure the connection strength of the top cover 310 when it is subsequently welded to the shell 100.

[0124] Among them, the top cover 310 is provided with a pole hole, a liquid injection hole, and an explosion-proof valve hole (when the explosion-proof valve 340 is a separate component assembled on the top cover 310), and the hole walls of the pole hole, the liquid injection hole, and the explosion-proof valve hole do not need to be subjected to oxidation insulation treatment.

[0125] An embodiment of the present application also provides a method for manufacturing a top cover assembly, the manufacturing method comprising:

[0126] S100, providing a top cover 310, wherein the top cover 310 includes a first surface and a second surface opposite to each other, and a pole hole penetrating the first surface and the second surface is formed on the top cover;

[0127] S300, shielding the top cover 310, exposing only a second area on the first surface other than the first area surrounding the pole hole;

[0128] S400, forming a first insulating oxide layer 410 on the second region of the first surface;

[0129] S500, inserting the pole 320 into the pole hole;

[0130] S600 , forming an insulating member 330 between the hole wall of the pole hole and the outer peripheral surface of the pole 320 , and on the first area of ​​the first surface.

[0131] The manufacturing method of the top cover assembly provided in the present application is that the insulating member 330 located on the hole wall of the pole hole forms insulation between the pole 320 and the top cover 310, and the insulating member 330 located in the area surrounding the pole hole forms insulation between the top cover 310 when the adapter is subsequently set; the thickness of the formed first insulating oxide layer 410 is greatly reduced relative to the insulating member 330, so that the heat generated in the battery can be dissipated more quickly through the top cover 310, thereby improving the heat dissipation performance of the top cover assembly 300; in addition, by relatively reducing the area of ​​the insulating member 330, it is avoided that the insulating member 330 forms a structure such as a bump that blocks the flow of gas, so that when the battery cell 210 produces gas due to thermal runaway, the gas can be discharged from the explosion-proof valve of the top cover 310 in time, reducing the risk of battery explosion and improving the safety of the battery.

[0132] In one embodiment, Fig. 9 As shown, between step S100 and step S300, the manufacturing method further includes step S200, forming nano-scale micropores on the hole wall of the pole hole and the first area surrounding the pole hole on the first surface. Among them, the insulating member 330 is formed by injection molding between the hole wall of the pole hole and the outer peripheral surface of the pole 320, and on the first area of ​​the first surface. Nano-scale micropores are first formed on the hole wall of the pole hole of the top cover 310 and the area surrounding the pole hole on the first surface; then, the top cover 310 is blocked to expose only the second area outside the first area on the first surface; then, a first insulating oxide layer 410 is formed on the area of ​​the first surface of the top cover 310 that is not covered by the insulating member 330; after the first insulating oxide layer 410 is formed, the insulating member 330 is then formed on the area where the nano-scale micropores are formed, that is, the hole wall of the pole hole and the area surrounding the pole hole on the first surface by injection molding, thereby improving the bonding strength between the insulating member 330 and the top cover 310.

[0133] The surface of the metal top cover 300 may be nano-processed first, and then the insulating member 330 of the plastic material may be directly injection molded on the surface of the metal top cover 300, so that the metal and the plastic may be integrally molded, and finally the top cover 300 and the insulating member 330 are combined into a product.

[0134] Among them, the nano-scale micropores on the top cover 300 can be processed by nano-scale microporation on the surface of the metal top cover 300 through a chemical solution, so that the surface of the metal top cover 300 and the insulating part 330 of the plastic material can be better combined, thereby improving the connection strength, so as to overcome the problem of reduced connection strength caused by reducing the contact area between the insulating part 330 and the top cover 300 due to reducing the size of the insulating part 330, thereby ensuring the connection strength and reliability between the insulating part 330 and the top cover 300. For example, when the top cover 300 is an aluminum cover, the preparation of the micro-nano structure on the surface of the aluminum cover can be prepared by various methods such as physical, chemical solution method, magnetron sputtering, electrochemical method and laser processing; among them, the physical method is to use metal powder at the micron scale or nano powder at the nano scale to attach to the surface of the substrate, and then perform heat treatment to finally make a micro-nano structure; the chemical solution method is to deposit a certain concentration of aluminum ions on the surface of the substrate through a chemical reaction to finally obtain a micro-nano structure; the magnetron sputtering method usually uses a target material for sputtering, and can also prepare a better micro-nano structure by controlling the deposition conditions and methods; the electrochemical method is to use electrolysis to anodic oxidation of the substrate surface to form a micro-nano structure; laser processing uses photochemical reaction or laser scanning to prepare the micro-nano structure; the present disclosure does not limit the specific method of forming nanoscale micropores.

[0135] After the top cover 310 is subjected to oxidation insulation treatment, the insulating member 330 is then formed on the top cover 310 by injection molding, and then the pole 320 is assembled to the insulating member 330 and the top cover 310. If nano-scale micropores are formed in the region where the insulating member 330 is formed on the top cover 310, the top cover 310 can be treated before the oxidation insulation process to form nano-scale micropores, and then the top cover 310 is subjected to oxidation treatment; this avoids damage to the first insulating oxide layer 410 when the nano-scale micropores are formed after the oxidation treatment.

[0136] When the top cover 310 is oxidized, a sacrificial layer may be used to cover all areas of the top cover 310 except the first surface, leaving only the area of ​​the first surface not covered by the insulating member 330 exposed for oxidation.

[0137] When the shell 100 is oxidized, a sacrificial layer may be used to cover all areas of the shell 100 except the inner surface, leaving only the inner surface exposed for insulation oxidation treatment to form the third insulation oxide layer 430. Of course, for example, when the shell 100 is an aluminum shell, all surfaces of the shell 100 may be oxidized, that is, the third insulation oxide layer 430 is formed on all surfaces, so as to improve the wear resistance of the outer surface of the shell 100 through the third insulation oxide layer 430, and at the same time improve the insulation performance of the shell 100.

[0138] The sacrificial layer may be formed of a material that does not participate in the oxidation reaction, such as paraffin wax, which can be plated on a surface that does not need to be oxidized. Paraffin wax has high plasticity, which is convenient for exposing a preset surface through processing, and is also convenient for removal during the oxidation process. Alternatively, the sacrificial layer may be covered on a surface that does not need to be oxidized by pasting or the like, and this application does not limit this.

[0139] An embodiment of the present application also provides an electrical device, which may be an energy storage device, a vehicle, an energy storage container, etc. The electrical device includes the energy storage device described in the above embodiment, and the energy storage device supplies power to the electrical device. In the electrical device provided in the present application, in the top cover assembly 300 of the energy storage device, the insulating member 330 located on the hole wall of the pole hole forms insulation between the pole 320 and the top cover 310, and the insulating member 330 located on the area surrounding the pole hole forms insulation between the top cover 310 when the adapter is subsequently set; on the first surface of the top cover 310, the insulating member 330 is only located in the area surrounding the pole hole and does not completely cover the first surface of the top cover 310; the area of ​​the first surface of the top cover 310 not covered by the insulating member 330 is covered by a first insulating oxide layer 410 forms insulation, and the thickness of the first insulating oxide layer 410 is greatly reduced relative to the insulating member 330, so that the heat generated in the battery can be dissipated more quickly through the top cover 310, thereby improving the heat dissipation performance of the top cover assembly 300; in addition, by relatively reducing the area of ​​the insulating member 330, it is avoided that the insulating member 330 forms a structure such as a bump that blocks the flow of gas, so that when the battery cell 210 produces gas due to thermal runaway, the gas can be discharged from the explosion-proof valve of the top cover 310 in time, reducing the risk of battery explosion and improving the safety of electrical equipment.

[0140] In the application examples, the term "plurality" refers to two or more than two, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the application examples can be understood according to the specific circumstances.

[0141] In the description of the application embodiments, it is necessary to understand that the directions or positional relationships indicated by the terms "upper" and "lower" are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the application embodiments and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the application embodiments.

[0142] In the description of this specification, the description of the term "an embodiment" 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 application embodiment. 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.

[0143] The above are only preferred embodiments of the application embodiments and are not intended to limit the application embodiments. For those skilled in the art, the application embodiments may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application embodiments shall be included in the protection scope of the application embodiments.

Claims

1. A top cover assembly, characterized in that: include: A top cover (310), the top cover (310) comprising a first surface and a second surface opposite to each other, and a pole hole penetrating the first surface and the second surface is formed on the top cover (310); A pole (320), wherein the pole (320) is inserted into the pole hole; an insulating member (330), the insulating member (330) being formed on a hole wall of the pole hole and being located between the hole wall and an outer peripheral surface of the pole (320), and on a region surrounding the pole hole on the first surface of the top cover (310); A first insulating oxide layer (410) is formed on an area of ​​the first surface of the top cover (310) that is not covered by the insulating member (330).

2. The top cover assembly according to claim 1, characterized in that: Nanoscale micropores are formed on the hole wall of the pole hole and the area on the first surface where the insulating member (330) is formed. The insulating member (330) is formed on the hole wall of the pole hole and the area surrounding the pole hole on the first surface of the top cover (310) by a nano injection molding process.

3. The top cover assembly according to claim 1, characterized in that: The top cover assembly (300) further includes: An adapter plate (360), the adapter plate (360) being located on a side of the insulating member (330) facing away from the top cover (310) and being connected to the pole (320); a distance between an edge of an orthographic projection of the adapter plate (360) on the top cover (310) and an edge of an orthographic projection of the insulating member (330) on the top cover (310) being a, and a≤5 mm.

4. The top cover assembly according to claim 3, characterized in that: The orthographic projection of the adapter plate (360) on the top cover (310) completely overlaps with the orthographic projection of the insulating member (330) on the top cover (310).

5. The top cover assembly according to claim 1, characterized in that: The top cover assembly (300) further includes: An explosion-proof valve (340), wherein an explosion-proof hole is formed on the top cover (310), the explosion-proof valve (340) is arranged on the explosion-proof hole, and the orthographic projection of the explosion-proof valve (340) on the top cover (310) and the orthographic projection of the insulating member (330) on the top cover (310) have no overlapping parts; and a second insulating oxide layer (420) is formed on the surface of the explosion-proof valve (340) on the side facing the insulating member (330).

6. The top cover assembly according to claim 5, characterized in that: The density of the first insulating oxide layer (410) is greater than the density of the second insulating oxide layer (420).

7. The top cover assembly according to claim 5, characterized in that: The top cover (310) and the explosion-proof valve (340) are made of the same material, and the first insulating oxide layer (410) and the second insulating oxide layer (420) are made of the same material.

8. The top cover assembly according to claim 1, characterized in that: The orthographic projection area of ​​the first insulating oxide layer (410) on the first surface is 50% to 80% of the area of ​​the first surface.

9. The top cover assembly according to claim 1, characterized in that: The top cover (310) also includes a side wall connecting the first surface and the second surface, a step structure is formed on the side wall, and the step structure includes a tread and a riser, the tread connects the riser and the second surface, and the riser connects the tread and the first surface; the first insulating oxide layer (410) is not formed on the second surface, the tread, and the riser, at least on the portion connected to the tread.

10. The top cover assembly according to claim 1, characterized in that: The end of the pole (320) located on the insulating member (330) is flush with a surface of the insulating member (330) away from the top cover (310).

11. A method for manufacturing a top cover assembly, characterized in that: include: Providing a top cover (310), the top cover (310) comprising a first surface and a second surface opposite to each other, and forming a pole hole on the top cover (310) that passes through the first surface and the second surface; The top cover (310) is shielded to expose only a second area on the first surface other than a first area surrounding the pole hole; forming a first insulating oxide layer (410) on the second region of the first surface; Inserting a pole (320) into the pole hole; An insulating member (330) is formed between the hole wall of the pole hole and the outer peripheral surface of the pole (320), and on the first region of the first surface.

12. The manufacturing method according to claim 11, characterized in that: After forming a pole hole penetrating the first surface and the second surface on the top cover (310), and before shielding the top cover (310), the manufacturing method further comprises: Forming nanoscale micropores on the hole wall of the pole hole and on a first region surrounding the pole hole on the first surface; An insulating member (330) is formed between the hole wall of the pole hole and the outer peripheral surface of the pole (320), and on the first region where the nanoscale micropores are formed, by a nano injection molding process.

13. An energy storage device, characterized in that: include: A housing (100), wherein the housing (100) is formed with a receiving space having an opening (110), and a third insulating oxide layer (430) is formed on the inner wall of the housing (100); an electrode assembly (200), the electrode assembly (200) being arranged in the accommodation space, and the electrode assembly (200) being in direct contact with or having a gap with the third insulating oxide layer (430) formed on the inner wall of the shell (100), and the gap only having gas and / or electrolyte; The top cover assembly (300) according to any one of claims 1 to 10, wherein the top cover assembly (300) covers the opening (110), and the electrode assembly (200) is electrically connected to the pole (320).

14. An electrical device, characterized in that: The electrical equipment comprises the energy storage device described in claim 13, and the energy storage device supplies power to the electrical equipment.

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