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

Abstract

The application discloses a top cover assembly, an energy storage device and an electric equipment, and relates to the technical field of energy storage. The top cover assembly comprises a top cover, a pole, an injection layer and a first insulation oxide layer. The top cover comprises opposite first and second surfaces, and a pole hole penetrating through the first and second surfaces is formed in the top cover. A nanoscale micropore is formed on the hole wall of the pole hole and a region surrounding the pole hole on the first surface. The pole is arranged in the pole hole. The injection layer is formed on the nanoscale micropore of the hole wall and between the hole wall and the outer circumferential surface of the pole, and is also formed on the region with the nanoscale micropore on the first surface of the top cover. The first insulation oxide layer is formed on the region on the first surface of the top cover which is not covered by the injection layer. 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 after discharge to reactivate the active materials and continue to be used. Their recyclable nature has made them an increasingly popular power source for electrical devices.

[0003] As the demand for secondary batteries gradually increases, people's requirements for their performance in all aspects are also getting higher and higher, especially the requirements 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 this application, and therefore may include information that does not constitute prior art known to ordinary technicians in this field. Summary of the Invention

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

[0006] To achieve the above application objectives, 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 formed on the top cover passing through the first surface and the second surface;

[0009] A pole, the pole being inserted into the pole hole;

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

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

[0012] In the top cover assembly provided by 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 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 more quickly through the top cover, 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 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] An adapter plate is located on the side of the insulating member facing away from the top cover and is connected to the pole; the distance between the edge of the adapter plate's orthographic projection on the top cover and the edge of the insulating member's orthographic projection on the top cover is a, and a≤5mm.

[0017] The top cover assembly provided in this embodiment has a first insulating oxide layer formed on the top cover. Therefore, the distance between the edge of the positive projection of the adapter plate on the top cover and the edge of the positive 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 from being too large, and avoiding the formation of bumps on the insulating member, 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; 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 more quickly through the top cover, 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 part on the top cover, that is, the shape and size of the adapter and the insulating part are completely consistent. The insulating part ensures the reliability of insulation between the adapter and the top cover, while avoiding the insulating part 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 is provided with an explosion-proof hole on the top cover, the explosion-proof valve is arranged on the explosion-proof hole, the orthographic projection of the explosion-proof valve on the top cover and the orthographic projection of the insulating member on the top cover have no overlapping part; 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 this embodiment is configured so that the orthographic projection of the explosion-proof valve on the top cover has no overlapping portion with 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 will not be unable to reach the explosion-proof valve in time for discharge, thereby reducing the risk of battery explosion. 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 one 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. This avoids the situation where the battery explodes due to the increased 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 one embodiment of the present application, the top cover and the explosion-proof valve are made of the same material, and the first insulating oxide layer and the second insulating oxide layer are made of the same material.

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

[0027] According to an embodiment of the present application, an orthographic projection area 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 correspond to those of the insulating member, that is, the area on the first surface of the top cover not covered by the insulating member can 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, which reduces 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 riser of the top cover connected to the tread, thereby facilitating 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 located 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 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 passing through the first surface and the second surface;

[0035] Covering the top cover to expose only a second area of ​​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 this 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 more quickly through the top cover, 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 one embodiment of the present application, after forming the pole hole penetrating the first surface and the second surface on the top cover and before covering the top cover, the manufacturing method further includes:

[0041] forming nanoscale micropores on the hole wall of the pole hole and a first area 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 a nano injection molding process.

[0043] The manufacturing method of the top cover assembly provided by the embodiment first forms nanoscale micropores on the hole wall of the pole hole of the top cover and the first surface and the region surrounding the pole hole; then, by shielding the top cover, only the second region other than the first region on the first surface is exposed; then, a first insulating oxide layer is formed on the region of the first surface of the top cover which is not covered by the insulating member; after the first insulating oxide layer is formed, the insulating member is formed on the region with the nanoscale micropores by the injection molding process, that is, the hole wall of the pole hole and the region surrounding the pole hole on the first surface of the top cover, so that the bonding strength between the insulating member and the top cover is improved.

[0044] According to yet another aspect of the present application, a power storage device is provided, the power storage device comprising:

[0045] a housing formed with a receiving space with an opening, a third insulating oxide layer formed on the inner wall of the housing;

[0046] an electrode assembly disposed in the receiving space, and the electrode assembly directly abutting against or having a gap with the third insulating oxide layer formed on the inner wall of the housing, the gap only having gas and / or electrolyte;

[0047] a top cover assembly described above covering the opening, the electrode assembly being electrically connected with the pole.

[0048] The power storage device provided by the embodiment forms insulation between the pole and the top cover by the insulating member on the hole wall of the pole hole, and forms insulation between the top cover when the insulating member on the region surrounding the pole hole is formed for the subsequent setting of the adapter piece; on the first surface of the top cover, the insulating member is only located on the region surrounding the pole hole and does not cover the entire first surface of the top cover; insulation is formed on the region of the first surface of the top cover which is not covered by the insulating member by setting a first insulating oxide layer, 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 more quickly dissipated through the top cover, thereby improving the heat dissipation performance of the top cover assembly; in addition, by relatively reducing the area of the insulating member, the insulating member is prevented from being formed with a protrusion or other structure which blocks the flow of gas, so that when the battery cell is in thermal runaway and gas is generated, the gas can be promptly discharged from the explosion-proof valve of the top cover, reducing the risk of explosion of the battery and improving the safety of the power storage device.

[0049] According to still another aspect of the present application, a power utilization device is provided, characterized in that the power utilization device comprises the power storage device described above, and the power storage device supplies power to the power utilization device.

[0050] In the electrical equipment provided by this embodiment, in the energy storage device and the top cover assembly, 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 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 part 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 part, and the thickness of the first insulating oxide layer is greatly reduced relative to the insulating part, 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; 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 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 accompanying drawings.

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

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

[0055] Figure 3 An exploded diagram 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 structural diagram 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 in accordance with an embodiment of the present application;

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

[0061] Figure 9 A flow chart of a method for manufacturing a top cover assembly provided in accordance with 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 tab; 230, negative electrode tab;

[0067] 300, top cover assembly; 310, top cover; 320, pole; 321, positive pole; 322, negative pole; 330, insulator; 331, positive insulator; 332, negative insulator; 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 many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. Like reference numerals in the figures represent like or similar structures, and thus their detailed description will be omitted.

[0070] Because the energy people need is highly temporal and spatially dependent, in order to rationally utilize energy and improve its efficiency, 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, and then release it in a specific form based on future application needs. As we all know, the current main way to generate green electricity is to replace fossil energy with green energy.

[0071] Current green energy sources mainly include solar energy, wind energy, and hydropower. 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 (insufficient 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 curtailment" due to insufficient electricity demand or insufficient grid acceptance capacity.

[0072] And to solve the problem of insufficient power demand or insufficient grid accommodation, it must rely on energy storage devices. That is, through energy storage devices, the electrical energy is converted into other forms of energy through physical or chemical means for storage, and when needed, the energy stored in the energy storage device is converted into electrical energy and released. Simply put, the energy storage device is like a large "power bank". When the light energy and wind energy are sufficient, the electrical energy is stored, and when needed, the stored electrical energy is released.

[0073] Current energy storage (i.e. energy storage) application scenarios are relatively wide, including power generation side energy storage, grid side energy storage, renewable energy grid connected energy storage, and user side energy storage, etc. The corresponding types of energy storage devices include:

[0074] (1) Large energy storage containers applied in grid side energy storage scenarios, which can be used as high-quality active and reactive power regulation power sources in the grid, realizing load matching in time and space, enhancing renewable energy consumption capacity, and having great significance in grid system backup, relieving peak load power supply pressure and peak regulation;

[0075] (2) Small and medium-sized energy storage cabinets applied in industrial and commercial energy storage scenarios (banks, shopping malls, etc.) on the user side and small household energy storage boxes applied in household energy storage scenarios on the user side, the main operation mode is "peak clipping and valley filling". Because there is a big price difference in electricity charges according to the electricity demand at peak and valley positions, after users have energy storage equipment, in order to reduce costs, they usually charge the energy storage cabinet / box during the low electricity price period; During the peak electricity price period, the electricity in the energy storage device is released for use, in order to achieve the purpose of saving electricity charges. In addition, in remote areas, as well as areas with high incidence of natural disasters such as earthquakes and hurricanes, the existence of household energy storage devices is equivalent to the user providing a backup power source for himself and the grid, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0076] Taking the household energy storage scenario in the user side energy storage as an example, Figure 1 shows a household energy storage system, which includes an energy storage device 1 and an electrical energy conversion device 2 (such as a photovoltaic panel), and a user load 3 (such as street lamps, household appliances, etc.), the energy storage device 1 is a small energy storage box, which can be installed on the outdoor wall through wall hanging. Specifically, the electrical energy conversion device 2 can convert solar energy into electrical energy during the low electricity price period, and store it through the energy storage device 1, and then supply it to the user load 3 for use during the peak electricity price period, or supply it to the user load 3 for use when the grid is powered off / power off.

[0077] In conjunction with the aforementioned physical or electrochemical energy storage, taking electrochemical energy storage as an example, energy storage device 1 includes at least one chemical battery, utilizing the chemical elements within the chemical battery as an energy storage medium, with the charging and discharging process achieved through chemical reactions or changes in the energy storage medium. Simply put, the electrical energy generated by solar energy or wind energy is stored in at least one set of chemical batteries through chemical reactions or changes in the energy storage medium. When external electrical energy usage reaches a peak, the energy stored in the at least one set of chemical batteries is released for use through chemical reactions or changes in the energy storage medium, or transferred to areas with power shortages for reuse.

[0078] In related technologies, when the battery cells generate 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 cells to be overheated and cause thermal runaway.

[0079] To address the above technical issues, 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. The single cell 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, or rectangular, etc., and the embodiments of the present application do not impose any restrictions on 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 housing 100 , an electrode assembly 200 and a top cover assembly 300 . The housing 100 is formed with a receiving space having an opening 110 . The top cover assembly 300 covers the opening 110 of the housing 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. A pole hole penetrating the first surface and the second surface is formed on the top cover 310; the pole 320 is arranged in 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 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 of ​​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, nanoscale micropores are formed on the 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 wall of the pole hole and the area surrounding the pole hole on the first surface of the top cover 310 using a nano-injection molding process. By forming the nanoscale micropores on the wall of the pole hole of the top cover 310 and the area surrounding the pole hole on the first surface, and by forming the insulating member 330 using an injection molding process in the area where the nanoscale micropores are pre-formed, namely, the wall of the pole hole and the area surrounding the pole hole on the first surface, the bonding strength between the insulating member 330 and the top cover 310 is improved.

[0085] Nanoinjection molding refers to a nanomolding process that combines metal and plastic using nanotechnology. The metal top cover 300 is first nano-processed, and then the plastic insulating member 330 is directly injection-molded onto the metal top cover 300, allowing the metal and plastic to be integrally formed, ultimately combining the top cover 300 and insulating member 330 into a single 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 further includes an adapter plate 360, which is located on the side of the insulating member 330 facing away from the top cover 310 and is connected to the pole 320; the insulating member 330 forms insulation between the adapter plate 360 ​​and the top cover 310, and the electrode assembly 200 is electrically connected to the pole 320 through the adapter plate 360.

[0088] The distance between the edge of the adapter plate 360 ​​projected onto the top cover 310 and the edge of the insulating member 330 projected onto 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 adapter plate 360 ​​projected onto the top cover 310 and the edge of the insulating member 330 projected onto the top cover 310 here refer to the outer edge of the adapter plate 360 ​​and the outer edge of the insulating member 330. By ensuring that the distance between the edge of the positive projection of the adapter plate 360 ​​on the top cover 310 and the edge of the positive projection of the insulating member 330 on the top cover 310 is ≤5mm, the shape and size of the adapter plate 360 ​​and the insulating member 330 correspond to each other, thereby achieving insulation between the adapter plate 360 ​​and the top cover 310, avoiding the insulating member 330 from being too large, and avoiding the formation of bumps on the insulating member 330, 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 formed by a redox reaction of electroplating. For example, the insulating oxide layer may be formed by electroplating on the area of ​​the first surface of the top cover 310 not covered by the insulating member 330 by vapor deposition. Alternatively, the insulating oxide layer may be formed by electrophoresis on the area of ​​the first surface of the top cover 310 not covered by the insulating member 330 by electroplating. For example, the insulating oxide layer may be formed by electroplating on the area of ​​the first surface of the top cover 310 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 on the metal surface through an oxidation reaction. 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 the 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: oxidation treatment by immersing the metal in a chemical solution with an oxidant, such as anodic oxidation method and chemical oxidation method; 3. Electrochemical oxidation method: applying an electric current in the electrolyte, such as anodic oxidation 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 areas 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 this application is not limited to this. It can form a dense insulating oxide film through an oxidation reaction on its surface. By oxidizing the surface of the top cover 310 to form a dense insulating oxide film, the insulating oxide film is a denatured 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, further reducing 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 piece 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, if Figure 3As shown, the electrode assembly 200 includes multiple tabs, including at least one positive tab 220 and at least one negative tab 230; the single battery 10 includes multiple adapters 360, including at least one positive adapter 361 and at least one negative adapter 362; the single battery 10 includes multiple posts 320, including at least one positive post 321 and at least one negative post 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 post 321 is connected to the positive adapter 361, and the negative post 322 is connected to the negative adapter 362.

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

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

[0097] The negative tab 230 of the battery cell 210 is electrically connected to the negative electrode post 322 via 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 insulator 332 on the top cover 310 is a, where 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 insulator 332, or the edge of the negative electrode insulator 332 and the edge protruding from the negative electrode adapter 362, are in contact with each other.

[0098] In one embodiment, 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. By ensuring that the orthographic projection of the adapter plate 360 ​​on the top cover 310 and the orthographic projection of the insulating member 330 on the top cover 310 completely overlap, that is, the shape and size of the adapter plate 360 ​​and the insulating member 330 are completely consistent, the insulating member 330 ensures the reliability of the insulation between the adapter plate 360 ​​and the top cover 310, while preventing the insulating member 330 from being too large. This allows the gas to be discharged promptly from the explosion-proof valve of the top cover 310 when the battery cell 210 thermally runs away and produces gas, thereby reducing the risk of explosion.

[0099] Among them, such as Figures 4 to 6 As shown, the orthographic projection of the positive electrode adapter 361 on the top cover 310 completely overlaps with the orthographic projection of the positive electrode insulator 331 on the top cover 310, and the orthographic projection of the negative electrode adapter 362 on the top cover 310 completely overlaps with the orthographic projection of the negative electrode insulator 332 on the top cover 310. This allows the top cover 310 and the electrode assembly 200, excluding the positive electrode insulator 331 and the negative electrode insulator 332, to form an exhaust and heat dissipation path, thereby improving heat dissipation. Furthermore, this allows gas generated by the battery cells 210 to be concentrated at the top cover 310, allowing for timely venting when the gas pressure is high, reducing the risk of explosion and improving battery reliability. Furthermore, by reducing the size of 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 battery cell 10. When multiple battery cells 10 are grouped, the total weight of the grouped battery cells 10 can be reduced, thereby reducing the weight of the energy storage device, achieving lightweight design and enhancing product market competitiveness.

[0100] Of course, the orthographic projection of the positive electrode adapter 361 on the top cover 310 may completely coincide 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 coincide 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 coincide 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 coincide with the orthographic projection of the negative electrode insulating member 332 on the top cover 310. This application does not impose any restrictions on this.

[0101] In one embodiment, Figures 3 to 6As shown, the positive electrode insulator 331 has a recess formed therein for the positive electrode post 321. The positive electrode post 321 includes a fixing portion located within the recess. The recess is quasi-rectangular, aligning the positive electrode post 321 with the positive electrode insulator 331 in both the width direction X and the length direction Y. This allows for quick assembly of the positive electrode post 321 and the positive electrode insulator 331, while also improving assembly accuracy. The negative electrode insulator 332 has a recess formed therein for the negative electrode post 322. The negative electrode post 322 includes a fixing portion located within the recess. The recess is quasi-rectangular, aligning the negative electrode post 322 with the negative electrode insulator 332 in both the width direction X and the length direction Y. This allows for quick assembly of the negative electrode post 322 and the negative electrode insulator 332, while also improving 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 in the insulating member 330. By aligning the end of the pole 320 located on the insulating member 330 with the surface of the insulating member 330 away from the top cover 310, the adapter 360 is facilitated to electrically connect with the pole 320 on the insulating member 330. Of course, the end of the pole 320 located on the insulating member 330 can be arranged to protrude from the surface of the insulating member 330 away from the top cover 310, and this application is not limited to this.

[0103] Among them, when the insulating member 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 member 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 through the injection molding process, and finally the insulating member 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, Figures 2 to 4 and Figure 7 As shown, the top cover assembly 300 further includes an explosion-proof valve 340, which is provided 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 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 other methods; 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 the internal gas pressure of the battery being too high and causing an explosion.

[0109] When the explosion-proof valve 340 is installed in the explosion-proof hole by welding or other methods, a second insulating oxide layer 420 can be formed on the surface of the explosion-proof valve 340 facing the insulating member 330 before welding the explosion-proof valve 340. Alternatively, after welding the explosion-proof valve 340, the second insulating oxide layer 420 can be formed on the surface of the explosion-proof valve 340 facing the insulating member 330 using the same process as the top cover 310. In this case, the second insulating oxide layer 420 and the first insulating oxide layer 410 are the same insulating oxide layer. When a notch is formed in the top cover 310, and the portion surrounded by the notch serves as the explosion-proof valve 340, the second insulating oxide layer 420 can be formed on the surface of the explosion-proof valve 340 facing the insulating member 330 using the same process as the top cover 310. In this case, the second insulating oxide layer 420 and the first insulating oxide layer 410 are the same insulating oxide layer.

[0110] Specifically, by forming a notch on the top cover 310 and using the portion surrounded by the notch as the explosion-proof valve 340 , the material of the explosion-proof valve 340 is the same as that of the top cover 310 , and the second insulating oxide layer 420 is made of the same material as the first insulating oxide layer 410 , thereby reducing process costs and improving process efficiency.

[0111] Among them, such as Figure 4As shown, the orthographic projection of the explosion-proof valve 340 on the top cover 310 does not overlap with the orthographic projection of the insulating member 330 on the top cover 310. By ensuring that 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 do not overlap, 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 will not be able to 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 battery's gas production not being able to be discharged in time and causing an explosion, 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, which is located between the positive electrode post 321 and the negative electrode post 322. Electrolyte is injected into the battery cell 210 through the injection hole 350, and the electrolyte can evenly infiltrate the battery cell 210, ensuring the electrolyte infiltration efficiency. The injection hole 350 is provided with a sealing plug 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 arranged in the accommodation space, and the electrode assembly 200 is insulated from the shell 100 by the third insulating oxide layer 430. The single battery 10 provided by the application has the following advantages: the electrode assembly 200 is arranged in the accommodation space, the third insulating oxide layer 430 is formed on the inner surface of the shell 100, and the electrode assembly 200 is insulated from the shell 100 by the third insulating oxide layer 430, that is, the insulation between the electrode assembly 200 and the shell 100 is directly achieved, avoiding the arrangement of other insulating structural members between the shell 100 and the electrode assembly 200, so that the heat generated by the electrode assembly 200 can directly pass through the shell 100 and be dissipated, the heat transmission path is short, the heat dissipation is fast, and the problem of thermal runaway of the electrode assembly 200 caused by excessively high temperature of the electrode assembly 200 is avoided; at the same time, when the electrode assembly 200 produces gas due to thermal runaway, the gas can not be blocked by other insulating structural members arranged between the shell 100 and the electrode assembly 200 and can be discharged in time through the top cover 310, thereby reducing the risk of explosion of the battery.

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

[0116] As shown in the figure, Figure 2 The shell 100 and the top cover assembly 300 cooperate to form a quadrangular prism shell, and the square battery includes an electrode assembly 200 and an electrolyte in the shell 100. The electrode assembly 200 includes an electrode core 210, a positive electrode tab 220 and a negative electrode tab 230. The electrode core 210 has a positive electrode tab, a negative electrode tab and a diaphragm arranged between the positive electrode tab and the negative electrode tab, which are stacked with each other. The positive electrode tab, the negative electrode tab and the diaphragm arranged between the positive electrode tab and the negative electrode tab are wound to obtain a wound electrode core 210. Alternatively, the electrode core 210 can be a stacked electrode core 210.

[0117] In one embodiment, the electrode assembly 200 directly abuts against the inner sidewall of the housing 100 or there is a gap between the electrode assembly 200 and the inner sidewall of the housing 100 , and only gas and / or electrolyte are present in the gap. A third insulating oxide layer 430 is formed on the inner wall of the shell 100. 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, which avoids the problem of the battery cell 210 being overheated and causing thermal runaway 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, the need to provide other insulating structural members between the inner wall of the shell 100 and the electrode assembly 200 is avoided, thereby reducing the weight of the shell 100 and thus reducing the weight of the single cell 10. When multiple single cells 10 are grouped, the total weight of the multiple grouped single cells 10 can be reduced, thereby reducing the weight of the energy storage device and achieving lightweighting.

[0118] In one embodiment, the end of the electrode assembly 200 away from the top cap assembly 300 directly abuts the bottom surface of the housing 100. A third insulating oxide layer 430 is formed on the bottom surface of the housing 100. The end of the electrode assembly 200 away from the top cap assembly 300 directly abuts the bottom of the housing 100. The third insulating oxide layer 430 achieves insulation between the bottom of the electrode assembly 200 and the bottom of the housing 100, eliminating the need for other insulating components, such as a bottom support plate. This allows heat generated by the electrode assembly 200 to dissipate directly through the bottom of the housing 100, resulting in a shorter heat transfer path and faster heat dissipation, thereby avoiding the problem of excessive temperature of the battery cell 210 causing thermal runaway 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 blocked by other insulating structural components between the bottom of the housing 100 and the bottom of the electrode assembly 200 and will not be able to reach the top cap 310 in time and be discharged through the explosion-proof valve, thereby reducing the risk of explosion. In addition, the need to provide other insulating structural members between the shell 100 and the electrode assembly 200 is avoided, thereby reducing the weight of the shell 100 and thus reducing the weight of the single cell 10. When multiple single cells 10 are grouped, the total weight of the multiple grouped single cells 10 can be reduced, thereby reducing the weight of the energy storage device and achieving lightweighting.

[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. This allows the insulating oxide layers to be formed using the same oxidation process, which can reduce manufacturing costs and improve manufacturing efficiency. Of course, the top cover 310 and the housing 100 may also be made of different materials, and the insulating oxide layers formed on the top cover 310 and the housing 100 may also be different, and this application does not impose any restrictions on 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 serves 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 fall within the scope of protection 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 that of the first insulating oxide layer 410 , which is not limited in this application.

[0122] In one embodiment, the top cover 310 further includes a side wall connecting the first surface and the second surface. No insulating oxide layer is formed on the second surface and the side wall, which facilitates 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; since 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, the first insulating oxide layer 410 may be formed on the portion of the riser connected to the first surface due to process reasons, 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 when the top cover 310 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 further provides a method for manufacturing a top cover assembly, the 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 is formed on the top cover and passes through the first surface and the second surface;

[0127] S300, shielding the top cover 310, exposing only a second area of ​​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, Figure 9 As shown, between steps S100 and S300, the manufacturing method further includes step S200, forming nanoscale micropores on the wall of the pole hole and a first region surrounding the pole hole on the first surface. Insulating member 330 is formed by injection molding between the wall of the pole hole and the outer peripheral surface of pole 320, as well as on the first region of the first surface. Nanoscale micropores are first formed on the wall of the pole hole and the region surrounding the pole hole on the first surface of top cover 310; then, by shielding top cover 310, only a second region outside the first region on the first surface is exposed; then, a first insulating oxide layer 410 is formed on the region of the first surface of top cover 310 not covered by insulating member 330; after forming first insulating oxide layer 410, insulating member 330 is then formed by injection molding on the region where the nanoscale micropores are formed, namely, the wall of the pole hole and the region surrounding the pole hole on the first surface, thereby improving the bonding strength between insulating member 330 and top cover 310.

[0133] Among them, the surface of the metal top cover 300 can be nano-processed first, and then the plastic insulating member 330 can be directly injection molded on the surface of the metal top cover 300, so that the metal and plastic can 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 method, electrochemical method and laser processing; among them, the physical method is to use metal powder at the micron scale or nanopowder at the nanoscale 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, and 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 an oxidation insulation treatment, the insulating member 330 is then formed on the top cover 310 through an injection molding process, and the pole 320 is then assembled to the insulating member 330 and the top cover 310. If nano-scale micropores are to be formed in the region of the top cover 310 where the insulating member 330 is to be formed, the top cover 310 can be treated to form the nano-scale micropores before the oxidation insulation process, and then the top cover 310 can be subjected to an oxidation treatment; this avoids damage to the first insulating oxide layer 410 caused by the nano-scale micropores 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 areas of the first surface not covered by the insulating member 330 exposed for oxidation.

[0137] In the process of oxidizing the shell 100, the sacrificial layer can be used to cover all areas of the shell 100 except the inner surface, and only the inner surface is exposed for insulation oxidation treatment to form the third insulation oxide layer 430. Of course, when the shell 100 is an aluminum shell, for example, all surfaces of the shell 100 can be oxidized, that is, the third insulation oxide layer 430 is formed on all surfaces, so that the wear resistance of the outer surface of the shell 100 is improved through the third insulation oxide layer 430, and the insulation performance of the shell 100 is improved.

[0138] The sacrificial layer can be formed of a material that does not participate in the oxidation reaction, such as paraffin or the like. The paraffin can be plated on the surface that does not need to be oxidized. The paraffin has high plasticity, which facilitates the exposure of the predetermined surface through processing, and also facilitates removal in the oxidation process. Alternatively, the sacrificial layer can be covered on the surface that does not need to be oxidized by pasting or the like, which is not limited in the present application.

[0139] The embodiments of the present application also provide a power utilization device, which can be an energy storage device, a vehicle, an energy storage container, etc. The power utilization device comprises the energy storage device described in the above embodiments, and the energy storage device supplies power to the power utilization device. In the power utilization device provided by the present application, the insulating piece 330 located on the hole wall of the pole hole forms insulation between the pole 320 and the top cover 310 in the top cover assembly 300 of the energy storage device, and the insulating piece 330 located on the area surrounding the pole hole forms insulation between the top cover 310 when the subsequent adapter piece is arranged. On the first surface of the top cover 310, the insulating piece 330 is only located in the area surrounding the pole hole, and does not cover the first surface of the top cover 310. The area of the first surface of the top cover 310 that is not covered by the insulating piece 330 is insulated by arranging the first insulation oxide layer 410, and the thickness of the first insulation oxide layer 410 is greatly reduced compared with the insulating piece 330, so that the heat generated in the battery can be more quickly dissipated 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 piece 330, the insulating piece 330 is prevented from forming a structure with a protrusion or the like that blocks the flow of gas, so that when the battery cell 210 produces gas due to thermal runaway, the gas can be timely discharged from the explosion-proof valve of the top cover 310, thereby reducing the risk of explosion of the battery and improving the safety of the power utilization device.

[0140] In the embodiments of the present application, the term "a plurality of" refers to two or more, unless otherwise explicitly limited. The terms "mount", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, "connect" can be fixed connection, or detachable connection, or integrally connected; "connected" can be directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0141] In the description of the application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the device or unit referred to must have a particular direction, be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation on the application.

[0142] In the description of the present application, the description of the term "one 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. In the present application, the illustrative description 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 is only a preferred embodiment of the application, and is not intended to limit the application. Those skilled in the art can make various modifications and changes to the application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the application shall be included in the protection scope of the application.

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, a pole hole penetrating the first surface and the second surface being formed on the top cover (310); A pole (320), the pole (320) being 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 an area 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, wherein: 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, wherein: The top cover assembly (300) further includes: An adapter plate (360), the adapter plate (360) is located on a side of the insulating member (330) facing away from the top cover (310) and is connected to the pole (320); a distance a 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) is provided, and a≤5mm.

4. The top cover assembly according to claim 3, wherein: 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, wherein: The top cover assembly (300) further includes: An explosion-proof valve (340) is provided, 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 portion; 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, wherein: 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, wherein: 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, wherein: The top cover (310) further comprises a side wall connecting the first surface and the second surface, a step structure being formed on the side wall, the step structure comprising a tread and a riser, the tread connecting the riser and the second surface, and the riser connecting 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 in the portion connected to the tread.

10. The top cover assembly according to claim 1, wherein: 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 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 the third insulating oxide layer (430) formed on the inner wall of the housing (100) or having a gap therebetween, wherein only gas and / or electrolyte is present in the gap; 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 includes the energy storage device according to claim 13, and the energy storage device supplies power to the electrical equipment.

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