Top cover, top cover assembly, energy storage device and energy storage system

Abstract

The disclosure provides a top cover, a top cover assembly, an energy storage device and an energy storage system, and relates to the technical field of energy storage. The top cover comprises a top surface and a back surface in a first direction, and an explosion-proof hole is formed in the top cover and penetrates the top surface and the back surface; wherein at least part of the area around the explosion-proof hole on the top surface is a bevel, the bevel extends along a second direction and / or a third direction away from the side of the explosion-proof hole, and the bevel is inclined towards the back surface in the extension direction; the second direction intersects the first direction, and the third direction intersects the first direction and the second direction. The top cover provided by the disclosure can improve the safety of the energy storage device.

Description

Technical Field

[0001] This disclosure relates to the field of energy storage technology, and more specifically, to a top cover, a top cover assembly, an energy storage device, and an energy storage system. Background Technology

[0002] Secondary batteries, also known as rechargeable batteries or storage batteries, are batteries that can be recharged after being discharged, allowing the active materials to be reactivated and reused. The recyclable nature of secondary batteries has made them a primary power source for electrical equipment.

[0003] As the demand for rechargeable batteries gradually increases, people are also placing higher demands on their performance in all aspects, especially on battery safety.

[0004] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this disclosure is to provide a top cover, a top cover assembly, an energy storage device, and an energy storage system that can improve the safety of the energy storage device.

[0006] According to one aspect of this disclosure, a top cover is provided for an energy storage device, the top cover including a top surface and a back surface along a first direction, and an explosion-proof hole is formed on the top cover penetrating the top surface and the back surface;

[0007] Wherein, at least a portion of the area surrounding the explosion-proof hole on the top surface is an inclined surface, the inclined surface extends toward the side away from the explosion-proof hole along a second direction and / or a third direction, and the inclined surface is inclined toward the back side in the extension direction; the second direction intersects the first direction, and the third direction intersects the first direction and the second direction.

[0008] In one exemplary embodiment of this disclosure, the inclined surface extends from the edge of the explosion-proof hole toward the side away from the explosion-proof hole.

[0009] In one exemplary embodiment of this disclosure, the size of the top cover in the second direction is greater than the size in the third direction, and the inclined surface extends in the third direction to the edge of the top cover.

[0010] In an exemplary embodiment of this disclosure, the top cover includes a top patch and a top cover body, the top patch and the top cover body being stacked along the first direction; the surface of the top patch facing away from the top cover body along the first direction is the top surface, and the inclined surface is formed on the top patch.

[0011] In one exemplary embodiment of this disclosure, the top patch has a gap between itself and the top cover body along the first direction in the region where the inclined surface is formed.

[0012] In one exemplary embodiment of this disclosure, the top patch is a uniform thickness structure along the first direction, at least in the region where the slope is formed.

[0013] In one exemplary embodiment of this disclosure, the height of the gap decreases in the first direction along the second direction and / or the third direction in the direction away from the explosion-proof hole.

[0014] In one exemplary embodiment of this disclosure, the gap surrounds the explosion-proof hole.

[0015] In one exemplary embodiment of this disclosure, a heat insulation element is provided in the gap between the top patch and the top cover body.

[0016] In one exemplary embodiment of this disclosure, the inclined surface includes a plurality of inclined planes surrounding the explosion-proof hole.

[0017] In one exemplary embodiment of this disclosure, the plurality of inclined planes includes a first inclined plane and a second inclined plane, wherein the first inclined plane and the second inclined plane are disposed opposite to each other along the second direction or the third direction.

[0018] In one exemplary embodiment of this disclosure, the size of the top cover in the second direction is greater than the size in the third direction, and the first inclined plane and the second inclined plane are disposed opposite to each other along the third direction.

[0019] In one exemplary embodiment of this disclosure, the plurality of inclined planes includes a third inclined plane, a fourth inclined plane, a fifth inclined plane, and a sixth inclined plane. The third inclined plane and the fourth inclined plane are disposed opposite each other along the third direction, and the fifth inclined plane and the sixth inclined plane are disposed opposite each other along the second direction.

[0020] In one exemplary embodiment of this disclosure, the inclined surface surrounds the explosion-proof hole, and the inclined surface is a continuous curved surface in the direction surrounding the explosion-proof hole.

[0021] In one exemplary embodiment of this disclosure, the bevel on the top patch is formed by a stamping process.

[0022] In an exemplary embodiment of this disclosure, the top patch is provided with a first explosion-proof through hole, and the top cover body is provided with a second explosion-proof through hole. The first explosion-proof through hole and the second explosion-proof through hole communicate to form the explosion-proof hole. In the first direction, the orthographic projection of the second explosion-proof through hole is located within the orthographic projection of the first explosion-proof through hole.

[0023] According to another aspect of this disclosure, a top cover assembly is provided, the top cover assembly comprising:

[0024] The aforementioned top cover;

[0025] An explosion-proof valve is provided on the explosion-proof port;

[0026] An insulating element, which is stacked along the first direction on one side of the back side of the top cover.

[0027] According to another aspect of this disclosure, an energy storage device is provided, the energy storage device comprising:

[0028] A housing, the housing including a receiving space with an opening;

[0029] An electrode assembly, wherein the electrode assembly is housed in the receiving space;

[0030] The aforementioned top cover assembly covers the opening.

[0031] According to another aspect of this disclosure, an energy storage system is provided, which includes the energy storage device described above.

[0032] The top cover provided in this disclosure has at least a portion of the area surrounding the explosion-proof hole on the top surface set as a slope, and the slope is inclined towards the back side in the extending direction, that is, a slope structure is formed in the area around the explosion-proof hole. When the battery cell experiences thermal runaway, after the explosion-proof valve opens to release gas, the continuous reaction inside the cell will cause the insulating parts to melt and be ejected. At the same time, the positive electrode foil forms aluminum beads and is ejected from the cell. At this time, the ejected plastic carbonized debris, aluminum beads and other substances will slide or disperse away from the explosion-proof hole on the slope due to gravity, thereby preventing the ejected high-temperature substances from accumulating around the explosion-proof hole, thereby reducing the temperature in the area around the explosion-proof hole, and preventing the aluminum beads from contacting the carbonized debris and igniting in the area around the explosion-proof hole, effectively improving the safety of the battery cell.

[0033] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0034] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0035] Figure 1This is a schematic diagram of an energy storage system provided in one embodiment of the present disclosure.

[0036] Figure 2 This is a schematic diagram of a battery pack provided according to one embodiment of the present disclosure.

[0037] Figure 3 An exploded view of a battery pack provided for one embodiment of this disclosure.

[0038] Figure 4 This is a schematic diagram of a battery cell provided in one embodiment of the present disclosure.

[0039] Figure 5 An exploded view of a single battery cell provided in one embodiment of this disclosure.

[0040] Figure 6 This is a top view of a top cover assembly provided in one embodiment of the present disclosure.

[0041] Figure 7 This is a schematic diagram of the rear side of a top cover assembly provided in one embodiment of the present disclosure.

[0042] Figure 8 An exploded view of the top cover and insulating components provided in one embodiment of this disclosure.

[0043] Figure 9 This is a schematic diagram of the top surface of a top cover provided in one embodiment of the present disclosure.

[0044] Figure 10 This is a schematic diagram of the back of the top cover provided in one embodiment of the present disclosure.

[0045] Figure 11 An exploded view of the top patch and top cover body provided in one embodiment of this disclosure.

[0046] Figure 12 This is a schematic diagram of a top patch provided in one embodiment of the present disclosure.

[0047] Figure 13 A schematic diagram of a top patch provided for another embodiment of this disclosure.

[0048] Figure 14 A cross-sectional view of the top cover provided in one embodiment of this disclosure.

[0049] Figure 15 for Figure 14 Enlarged view of point A in the middle.

[0050] Figure 16 This is a cross-sectional view of a battery cell provided in one embodiment of the present disclosure.

[0051] Figure 17 for Figure 16Enlarged view of point B in the middle.

[0052] Explanation of reference numerals in the attached figures:

[0053] 10. Energy storage device; 20. High-voltage cable; 30. First power conversion device; 40. Second power conversion device;

[0054] 50. Battery pack; 510. Battery housing; 511. Lower housing; 512. Housing cover; 520. Battery module;

[0055] 100. Battery cell; 110. Top cover assembly; 111. Top cover; 1111. Top patch; 1112. Top cover body; 1113. Gap; 112. Top surface; 113. Back surface; 114. Explosion-proof hole; 1141. First explosion-proof through hole; 1142. Second explosion-proof through hole; 115. Sloping surface; 1151. First sloping plane; 1152. Second sloping plane; 1153. Third sloping plane; 1154. Fourth sloping plane; 1155. Fifth sloping plane; 1156. Sixth sloping plane; 116. Explosion-proof valve; 117. Insulating component; 1170. Explosion-proof mesh; 1181. First terminal post; 1182. Second terminal post; 120. Housing; 121. Opening; 130. Electrode assembly;

[0056] Z, first direction; X, second direction; Y, third direction. Detailed Implementation

[0057] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted.

[0058] Because the energy people need is highly time- and space-dependent, in order to make rational use of energy and improve energy efficiency, it is necessary to use a medium or device to store one form of energy in the same way or by converting it into another form of energy, and then release it in a specific form of energy based on future application needs.

[0059] Currently, the generation of green electricity generally relies on solar, wind, and hydropower. However, wind and solar power are generally characterized by strong intermittency and large fluctuations, which can cause grid instability, insufficient power during peak demand periods, and excessive power during off-peak periods. Unstable voltage can also damage the power grid. Therefore, insufficient electricity demand or insufficient grid capacity may lead to the problem of "wind and solar curtailment." Solving these problems requires energy storage. This involves converting electrical energy into other forms of energy through physical or chemical means and storing it. When needed, this energy can be converted back into electrical energy and released. Simply put, energy storage is like a large "power bank," storing electrical energy when solar and wind power are abundant and releasing the stored electricity when needed.

[0060] Taking electrochemical energy storage as an example, this solution provides an energy storage device for use in energy storage systems. The energy storage device is equipped with a set of chemical batteries, which mainly use the chemical elements in the batteries as energy storage media. The charging and discharging process is accompanied by the chemical reaction or change of the energy storage media. Simply put, the electrical energy generated by wind and solar energy is stored in the chemical batteries. When the use of external electrical energy reaches its peak, the stored electricity is released for use, or transferred to places with a shortage of electricity for use.

[0061] Current energy storage applications are quite widespread, including generation-side energy storage, grid-side energy storage, and consumption-side energy storage. The corresponding types of energy storage devices include:

[0062] Large-scale energy storage power stations applied to wind and solar power plants can assist renewable energy generation in meeting grid connection requirements and improve the utilization rate of renewable energy. As a high-quality active / reactive power source on the power supply side, energy storage power stations can achieve load matching of electricity in time and space, enhance the absorption capacity of renewable energy, reduce instantaneous power fluctuations, reduce the impact on the power grid, improve the absorption of new energy generation, and are of great significance in grid system backup, alleviating peak load power supply pressure, and peak and frequency regulation.

[0063] Energy storage containers used on the grid side mainly function as peak shaving, frequency regulation, and grid congestion relief. In terms of peak shaving, they can achieve peak shaving and valley filling of electricity load, that is, charging the energy storage battery when the electricity load is low and releasing the stored electricity during the peak electricity load period, thereby achieving a balance between power production and consumption.

[0064] Small-scale energy storage cabinets applied to the electricity consumption side primarily function to facilitate self-consumption of electricity, peak-valley price arbitrage, capacity cost management, and improve power supply reliability. Depending on the application scenario, electricity consumption-side energy storage can be categorized into commercial and industrial energy storage cabinets, residential energy storage devices, and energy storage charging piles, generally used in conjunction with distributed photovoltaic (PV) systems. Commercial and industrial users can utilize energy storage for peak-valley price arbitrage and capacity cost management. In electricity markets implementing peak-valley pricing, charging the energy storage system during low electricity prices and discharging it during high electricity prices allows for arbitrage, reducing electricity costs. Furthermore, industrial enterprises subject to two-part tariffs can utilize energy storage systems to store energy during off-peak hours and discharge it during peak load periods, thereby reducing peak power and the maximum declared demand, ultimately lowering capacity costs. Residential PV systems combined with energy storage can improve self-consumption levels. High electricity prices and poor power supply stability drive demand for residential PV installations. Given that photovoltaic power generation occurs during the day, while user load is generally higher at night, configuring energy storage can better utilize photovoltaic power, improve self-consumption levels, and reduce electricity costs. Furthermore, energy storage is needed in areas such as communication base stations and data centers for backup power.

[0065] In some embodiments, such as Figure 1 As shown, the embodiments of this disclosure are illustrated using a shared energy storage scenario on the generation / distribution side as an example, but the energy storage device disclosed herein is not limited to such a scenario.

[0066] This disclosure provides an energy storage system, comprising: a high-voltage cable 20, a first power conversion device 30, a second power conversion device 40, and the energy storage device 10 provided in this disclosure. In some embodiments of the power generation scenario, the second power conversion device 40 can be a wind power conversion device. Since the electricity generated by wind power conversion is volatile, random, and intermittent, the unstable electricity output by the wind power conversion device can be stored in the energy storage device 10 through grid connection. The energy storage device 10 is connected to the high-voltage cable 20 and outputs smooth electricity to the power consumption side of the distribution network, achieving peak shaving and frequency regulation, and ensuring stable grid operation; or, the wind power conversion device is always connected to the high-voltage cable 20. High-voltage cable 20 connects the wind power conversion device to the power consumption side of the distribution network under normal power generation conditions. When the current power load is low and the wind power conversion device generates excess power, the excess power is first stored in energy storage device 10 to reduce wind and solar curtailment rates and improve the problem of new energy power generation consumption. When the power load is high, the power grid issues an instruction to transmit the power stored in energy storage device 10 together with high-voltage cable 20 in grid-connected mode to supply power to the power consumption side. This provides the power grid with various services such as peak shaving, frequency regulation, and backup, giving full play to the peak shaving role of the power grid, promoting peak shaving and valley filling, and alleviating the power supply pressure of the power grid.

[0067] In some embodiments on the distribution network side, the first power conversion device 30 can be a photovoltaic power conversion device. The energy storage device 10 is connected to the high-voltage cable 20 and installed downstream of the high-voltage cable 20 between the user load and the user load. The power output by the photovoltaic power conversion device is stored in the energy storage device 10, which can respond in a timely manner to act as a backup power source when the power grid / distribution network fails. Alternatively, it can provide power supply support to alleviate line congestion when the high-voltage cable 20 transmission line is blocked, and to delay the economic pressure caused by the expansion of the power grid / distribution capacity when the power grid is planned to be expanded.

[0068] Optionally, the first power conversion device 30 may include, but is not limited to, a photovoltaic power conversion device, and the second power conversion device 40 may include, but is not limited to, a wind power conversion device. The first power conversion device 30 and the second power conversion device 40 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy and mechanical energy into electrical energy.

[0069] Optionally, the energy storage device 10 may include, but is not limited to, energy storage applications such as energy storage power stations, hydropower / thermal / wind power generation systems, solar power generation systems, mobile power systems, smart home systems, or temporary power supply systems, and may also be applied in multiple fields such as data centers, military equipment, aerospace, charging piles, and electric vehicles.

[0070] In some embodiments, such as Figure 2 and Figure 3 As shown, taking the energy storage device 10 as an example of a battery pack 50, the battery pack 50 includes a battery housing 510 and multiple battery modules 520. The battery housing 510 includes a lower housing 511 and a housing cover 512, and the housing cover 512 is fixedly / detachably connected to the lower housing 511 to form a battery compartment. Multiple battery modules 520 are located inside the battery compartment.

[0071] The battery compartment of the battery housing 510 can hold at least one battery module 520, such as one, two, four, five, six, seven, eight, or more. The more battery modules 520 there are, the higher the capacity of the battery pack 50, thus making it easier to meet market demands. For example, such as... Figure 3 As shown, the battery compartment of the battery box 510 can accommodate a total of eight battery modules 520, which are arranged in two rows along the length of the battery box 510 and four columns along the width of the battery box 510.

[0072] Each battery module 520 may include a pair of end plates arranged opposite each other along the cell arrangement direction, and a plurality of battery cells 100 located between the pair of end plates. The plurality of battery cells 100 and the pair of end plates may be fixed by binding tools such as cable ties. The plurality of battery cells 100 are arranged along the length direction of the battery box 510, and the plurality of battery cells 100 are connected to each other by cell connecting pieces to realize series / parallel electrical connection between the plurality of battery cells 100.

[0073] In this configuration, multiple battery cells 100 are connected in series, with each cell connector connected to the electrode terminals of different polarities on two battery cells 100 respectively; or, multiple battery cells 100 are connected in parallel in pairs and then connected in series between the groups, with each cell connector first connected to the electrode terminals of the same polarity on two battery cells 100 respectively, and then connected to the electrode terminals of opposite polarity on two other battery cells 100.

[0074] It is understood that the energy storage device 10 is not limited to the battery pack 50. The energy storage device 10 can be a single battery cell 100, or a battery module 520 composed of single battery cells 100, a battery cluster, a power bank, an energy storage cabinet / energy storage container, or other battery integrated systems. The actual application form of the energy storage device 10 provided in this disclosure embodiment can be, but is not limited to, the listed products, and can also be other application forms. This application embodiment does not strictly limit the application form of the energy storage device 10.

[0075] Optionally, the battery cell 100 can be, but is not limited to, at least one of cylindrical, prismatic, prismatic, or other shaped batteries. The battery cell 100 can be a rechargeable battery, meaning a battery cell 100 that can be recharged after discharge to activate its active materials and continue to be used. The battery cell 100 can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and this application does not specifically limit its use. Below, this disclosure uses a prismatic battery cell 100 as an example to provide a detailed illustrative description of the specific details of the energy storage device 10.

[0076] like Figure 4 and Figure 5 As shown, the square battery cell 100 includes a housing 120, an electrode assembly 130, and a top cover assembly 110. The housing 120 has a receiving space with an opening 121, and the top cover assembly 110 covers the opening 121 of the housing 120.

[0077] It should be noted that the square battery cell 100, i.e., the battery cell 100, can be a tetragonal prism-shaped battery, which is convenient for assembly into groups. A tetragonal prism-shaped battery refers to a battery with a prism shape, but it is not strictly limited that each side of the prism must be a straight line in the strict sense; the corners between the sides can be right angles, rounded corners, or chamfers. The casing 120 and the top cover assembly 110 cooperate to form a tetragonal prism-shaped outer shell. The square battery cell 100 includes an electrode assembly 130 and an electrolyte located within the casing 120. The electrode assembly 130 includes a cell, a positive electrode tab, and a negative electrode tab. The cell has positive and negative electrode plates stacked on top of each other, and a separator sheet disposed between the positive and negative electrode plates. The positive and negative electrode plates, as well as the separator sheet disposed between the positive and negative electrode plates, are wound together to obtain a wound cell. Optionally, the cell can be a stacked cell.

[0078] Among them, such as Figures 6-8 As shown, the top cover assembly 110 includes a top cover 111, a first electrode post 1181, a second electrode post 1182, and an insulating member 117. The top cover 111 includes a top surface 112 and a back surface 113, which are opposite to each other. A first electrode post hole and a second electrode post hole are formed on the top cover 111, penetrating the top surface 112 and the back surface 113. The first electrode post 1181 is inserted into the first electrode post hole, and the second electrode post 1182 is inserted into the second electrode post hole. The insulating member 117 is stacked on the back surface 113 of the top cover 111 along a first direction Z, and the top cover 111 is insulated from the electrode assembly 130. The first electrode post 1181 and the second electrode post 1182 have opposite polarities. For example, the first electrode post 1181 can be a negative electrode post, and the second electrode post 1182 can be a positive electrode post.

[0079] The electrode assembly 130 includes at least one battery cell and multiple tabs connected to the battery cell, the multiple tabs including at least one positive tab and at least one negative tab; the top cover assembly 110 includes multiple adapter pieces, the multiple adapter pieces including at least one positive adapter piece and at least one negative adapter piece; the positive tab of each battery cell is electrically connected to the positive terminal through the positive adapter piece, and the negative tab of each battery cell is electrically connected to the negative terminal through the negative adapter piece.

[0080] A positive electrode insulating component may be provided between the positive electrode adapter and the top cover 111 to achieve insulation between the positive electrode adapter and the top cover 111; a negative electrode insulating component may be provided between the negative electrode adapter and the top cover 111 to achieve insulation between the negative electrode adapter and the top cover 111.

[0081] The top cover 111 is provided with an explosion-proof hole 114, and the explosion-proof valve 116 is installed on the explosion-proof hole 114 by welding or other means; or, by forming a groove on the top cover 111, the part surrounded by the groove serves as the explosion-proof valve 116; when the gas pressure inside the battery cell 100 is greater than the set critical value, the explosion-proof valve 116 opens to release gas, so as to avoid the battery cell 100 from exploding due to excessive gas pressure.

[0082] However, the inventors discovered that when the battery cell 100 experiences thermal runaway, the explosion-proof valve 116 first opens to release gas. Then, the internal reaction of the battery cell continues, and the temperature inside the casing 120 continues to rise, causing the insulating component (lower plastic) 117 to melt and spray out. In particular, the explosion-proof mesh 1170 on the lower plastic, which corresponds to the explosion-proof valve 116, will melt first and then spray out. At the same time, the high temperature inside the casing 120 causes the molten positive electrode foil to form aluminum beads. Due to the continuous reaction inside the battery cell, a large amount of gas is generated, which sprays out the molten aluminum beads. After the lower plastic melts, the gas inside the cell is mainly divided into two parts. Along the second direction X, one part is on the left side of the explosion-proof valve 116 and the other part is on the right side. The gas accumulates at the explosion-proof hole 114 and then is ejected. The ejected carbonized lower plastic debris, aluminum beads, etc., accumulate around the explosion-proof hole 114, causing the temperature in the area around the explosion-proof hole 114 to rise continuously. The aluminum beads ignite upon contact with the carbonized lower plastic debris, resulting in thermal runaway of the battery cell 100 and fire, which seriously affects the safety of the battery cell 100.

[0083] To address the aforementioned technical problems, embodiments of this disclosure provide a top cover 111 for a battery cell 100, such as... Figure 9 and Figure 10 As shown, the top cover 111 includes a top surface 112 and a back surface 113 along the first direction Z, and an explosion-proof hole 114 is formed on the top cover 111, penetrating the top surface 112 and the back surface 113. At least a portion of the area surrounding the explosion-proof hole 114 on the top surface 112 is an inclined surface 115. The inclined surface 115 extends along the second direction X and / or the third direction Y toward the side away from the explosion-proof hole 114, and the inclined surface 115 is inclined toward the back surface 113 in the extending direction. The second direction X intersects the first direction Z, and the third direction Y intersects both the first direction Z and the second direction X. The first direction Z may be the height direction of the battery cell 100, the second direction X may be the length direction of the battery cell 100, and the third direction Y may be the thickness direction of the battery cell 100.

[0084] The top cover 111 provided in this disclosure has at least a portion of the area surrounding the explosion-proof hole 114 on the top surface 112 set as a slope 115, and the slope 115 is inclined towards the back surface 113 in the extending direction, that is, a slope structure is formed in the area around the explosion-proof hole 114. When the battery cell 100 experiences thermal runaway, after the explosion-proof valve 116 opens to release gas, the continuous reaction inside the cell will cause the insulating component 117 to melt and be ejected. At the same time, the positive electrode foil forms aluminum molten beads and is ejected from the cell. At this time, the ejected plastic carbonized debris, aluminum molten beads and other substances will slide or disperse away from the explosion-proof hole 114 on the slope 115 by gravity, thereby preventing the ejected high-temperature substances from accumulating around the explosion-proof hole 114, thereby reducing the temperature in the area around the explosion-proof hole 114, and preventing the aluminum molten beads from contacting the carbonized debris and igniting in the area around the explosion-proof hole 114, effectively improving the safety of the battery cell 100.

[0085] In some embodiments, such as Figure 9 As shown, the area surrounding the explosion-proof hole 114 on the top surface 112 is all sloped 115, that is, the sloped surface 115 surrounds the explosion-proof hole 114, forming a sloped structure without dead angles in the area around the explosion-proof hole 114. Substances such as carbonized plastic debris and molten aluminum beads ejected from the explosion-proof hole 114 can slide or disperse away from the explosion-proof hole 114 due to the gravity provided by the sloped surface 115. This further prevents the high-temperature substances ejected from accumulating around the explosion-proof hole 114, further reduces the temperature in the area around the explosion-proof hole 114, further prevents the molten aluminum beads from contacting the carbonized debris and igniting in the area around the explosion-proof hole 114, and further improves the safety of the battery cell 100.

[0086] In some embodiments, such as Figure 9 As shown, the inclined surface 115 extends from the edge of the explosion-proof hole 114 toward the side away from the explosion-proof hole 114, that is, a slope structure with a reduced height is directly formed from the edge of the explosion-proof hole 114. In the event of thermal runaway of the battery cell 100, since the highest point of the slope structure is the edge of the explosion-proof hole 114, the ejected material can be guided by the inclined surface 115, preventing it from accumulating at the edge of the explosion-proof hole 114.

[0087] The inclined surface 115 extends continuously from the edge of the explosion-proof hole 114 toward the side away from the explosion-proof hole 114. The continuous inclined surface 115 can be a sloping plane or a curved surface with an arc in its extension direction. The continuous inclined surface 115 can continuously guide the ejected material, allowing it to slide down or disperse along the inclined surface 115 to the side of the inclined surface 115 away from the explosion-proof hole 114, that is, to slide down or disperse to the bottom of the slope structure, thereby allowing it to slide off the top cover 111 of the battery cell 100 or away from the explosion-proof hole 114. It is understood that the inclined surface 115 can also be intermittently inclined from the edge of the explosion-proof hole 114 toward the side away from the explosion-proof hole 114, that is, a stepped structure can be formed on the inclined surface 115; this disclosure does not limit this.

[0088] like Figure 9 As shown, the top cover 111 has a larger dimension in the second direction X than in the third direction Y, and the inclined surface 115 can extend to the edge of the top cover 111 in the third direction Y. Since the rectangular top cover 111 is usually relatively large in the second direction (length direction) X and relatively small in the third direction (width direction) Y, extending the inclined surface 115 to the edge of the top cover 111 in the third direction Y can make full use of the space of the top cover 111 in the third direction Y, so that the bottom side of the inclined surface 115 is directly located at the edge of the top cover 111. In the event of thermal runaway of the battery cell 100, the material ejected from the explosion-proof hole 114 can slide off the side of the top cover 111 via the inclined surface 115 and move away from the top cover 111. This completely prevents the ejected high-temperature material from accumulating around the explosion-proof hole 114, further reducing the temperature in the area around the explosion-proof hole 114. This also completely prevents the aluminum molten beads from coming into contact with carbonized debris and igniting in the area around the explosion-proof hole 114, further improving the safety of the battery cell 100.

[0089] Since the explosion-proof hole 114 is provided with other structural components such as the first pole post 1181 and the second pole post 1182 on both sides in the second direction X, the inclined surface 115 extends to a predetermined length in the second direction X. The length of the inclined surface 115 is sufficient to disperse the ejected high-temperature material away from the explosion-proof hole 114 and prevent it from accumulating at the explosion-proof hole 114.

[0090] In some embodiments, such as Figure 11 As shown, the top cover 111 includes a top patch 1111 and a top cover body 1112, with the top patch 1111 and the top cover body 1112 stacked along the first direction Z. By providing the top patch 1111 on the top cover 111, the top cover 111 of the battery can be protected from direct impact by external forces; on the other hand, it can also selectively serve as insulation to prevent short circuits between the battery and other circuits.

[0091] The top patch 1111 can have the same shape as the top cover body 1112. The top cover body 1112 can be made of the same material as the housing 120. That is, when the housing 120 is an aluminum shell, the top cover body 1112 can be a smooth aluminum sheet, and the top patch 1111 is attached to the smooth aluminum sheet.

[0092] The top patch 1111 has a first explosion-proof through hole 1141, and the smooth aluminum sheet has a second explosion-proof through hole 1142. The first explosion-proof through hole 1141 and the second explosion-proof through hole 1142 are aligned in the first direction Z and connected to form an explosion-proof hole 114. The explosion-proof valve 116 can be set on the smooth aluminum sheet, that is, on the second explosion-proof through hole 1142, and the explosion-proof valve 116 can be exposed through the first explosion-proof through hole 1141.

[0093] In the first direction Z, the orthographic projection of the second explosion-proof through hole 1142 is located within the orthographic projection of the first explosion-proof through hole 1141. That is, the size of the first explosion-proof through hole 1141 is larger than the size of the second explosion-proof through hole 1142. This facilitates the opening of the explosion-proof valve 116 on the second explosion-proof through hole 1142 through the first explosion-proof through hole 1141, which is beneficial for the ejected plastic carbonized debris, aluminum molten beads and other substances. At the same time, the larger size of the first explosion-proof through hole 1141 allows the ejected substances to diffuse better under the spraying force, thereby effectively preventing the ejected substances from accumulating around the explosion-proof through hole 114.

[0094] The inclined surface 115 is formed on the top patch 1111. The top patch 1111 is relatively easier to process than a plain aluminum sheet; for example, a flat sheet can be formed into a top patch 1111 with the inclined surface 115 through a stamping process. Using a stamping process to manufacture the top patch 1111 with the inclined surface 115 allows for rapid, mass production of top patches 1111 that meet design requirements, significantly improving production efficiency and reducing production costs. The stamping process can precisely control the shape, angle, and size of the inclined surface 115, ensuring consistent product quality and reducing errors and defects caused by manual processing or other processes. The stamping process avoids waste material during the formation of the inclined surface 115, reducing material costs. Furthermore, the stamping process is highly flexible; molds can be quickly changed according to different design requirements of the inclined surface 115 to produce top patches 1111 with different inclined surface shapes and parameters, meeting diverse product needs. Of course, a casting process or other methods can also be used to form the top patch 1111 with the inclined surface 115; this disclosure does not limit this approach.

[0095] It is understandable that the top cover 111 may also be formed only from a plain aluminum sheet, i.e., without the top patch 1111. In this case, the bevel 115 may be formed directly on the plain aluminum sheet.

[0096] In some embodiments, the inclined surface 115 includes a plurality of inclined planes surrounding the explosion-proof hole 114. By having the plurality of inclined planes surrounding the explosion-proof hole 114, the material ejected from the explosion-proof hole 114 can slide off or disperse through the inclined planes, reducing the possibility of the ejected material accumulating around the explosion-proof hole 114 and lowering the risk of temperature rise and fire caused by material accumulation.

[0097] In some embodiments, such as Figure 12 As shown, the plurality of inclined planes include a first inclined plane 1151 and a second inclined plane 1152, which are arranged opposite to each other along a second direction X or a third direction Y. By arranging the first inclined plane 1151 and the second inclined plane 1152 opposite to each other around the explosion-proof hole 114, the material ejected from the explosion-proof hole 114 can slide or disperse through the first inclined plane 1151 and the second inclined plane 1152, reducing the possibility of the ejected material accumulating around the explosion-proof hole 114 and reducing the risk of temperature rise and fire caused by material accumulation.

[0098] Among them, such as Figure 12 As shown, the size of the top cover 111 in the second direction X is larger than its size in the third direction Y. The first inclined plane 1151 and the second inclined plane 1152 are arranged opposite each other in the third direction Y, that is, the first inclined plane 1151 and the second inclined plane 1152 are arranged opposite each other in the direction where the size of the top cover 111 is smaller. This allows the material ejected from the explosion-proof hole 114 to slide off the top cover 111 in time through the first inclined plane 1151 and the second inclined plane 1152, thereby further reducing the possibility of the ejected material accumulating around the explosion-proof hole 114 and further reducing the risk of temperature rise and fire caused by material accumulation.

[0099] In some embodiments, such as Figure 13 As shown, multiple inclined planes include a third inclined plane 1153, a fourth inclined plane 1154, a fifth inclined plane 1155, and a sixth inclined plane 1156. The third inclined plane 1153 and the fourth inclined plane 1154 are arranged opposite each other along the third direction Y, and the fifth inclined plane 1155 and the sixth inclined plane 1156 are arranged opposite each other along the second direction X. Through the third inclined plane 1153, the fourth inclined plane 1154, the fifth inclined plane 1155, and the sixth inclined plane 1156, the material ejected from the explosion-proof hole 114 is effectively guided and dispersed in the second direction X and the third direction Y. Regardless of the direction in which the material ejected from the explosion-proof hole 114 falls, it will be guided by the corresponding inclined plane, preventing the ejected material from accumulating around the explosion-proof hole 114 and greatly reducing the risk of secondary combustion or blockage of the explosion-proof hole 114 due to material accumulation.

[0100] In some embodiments, the inclined surface 115 surrounds the blast hole 114, and the inclined surface 115 is a continuous curved surface in the direction surrounding the blast hole 114. The continuous curved surface provides a smoother and more fluid trajectory for the ejected material, preventing accumulation or splashing at turning points due to collision, and more effectively guiding the ejected material away from the blast hole 114, minimizing material residue around the blast hole 114 and reducing the risk of fire. The continuous curved surface design reduces stress concentration points. Under the impact of thermal runaway ejected material, stress concentration can easily occur at the junctions of discrete planes, leading to structural damage. The continuous curved surface allows the impact force to be distributed more evenly across the entire curved surface, enhancing the structural durability of the top cover 111 and improving its ability to withstand thermal runaway impacts. It is understood that the inclined surface 115 can also be formed by combining a curved surface and an inclined plane, i.e., a curved surface and an inclined plane combined in the direction surrounding the blast hole 114.

[0101] In some embodiments, such as Figures 14-17 As shown, the top patch 1111 has a gap 1113 between it and the top cover body 1112 along the first direction Z in the area where the inclined surface 115 is formed. When the battery cell 100 experiences thermal runaway, the inside of the cell is in a semi-closed state, and the internal temperature rises sharply, transferring the internal heat to the top cover body 1112. By setting the gap 1113 at the explosion-proof hole 114 between the top patch 1111 and the top cover body 1112, heat can be effectively isolated from the transfer from the top cover body 1112 to the top patch 1111, thereby preventing the possibility of the top patch 1111 and the plastic debris accumulated on its upper end being ignited by molten aluminum beads after the temperature rises too high, reducing the risk of thermal runaway fire.

[0102] The top patch 1111 has a uniform thickness structure along the first direction Z, at least in the area where the inclined surface 115 is formed. By making the top patch 1111 a uniform thickness structure, and when the side of the top cover body 1112 facing the top patch 1111 is flat or substantially flat, the size of the gap 1113 varies with the inclination of the inclined surface 115. The gap 1113 between the top of the inclined surface 115 and the top cover body 1112 is the largest. As the inclined surface 115 transitions from the top to the bottom, the height of the gap 1113 gradually decreases until the gap 1113 closes and disappears at the bottom of the inclined surface 115 where it fits against the top cover body 1112.

[0103] In particular, along the second direction X and / or the third direction Y in the direction away from the explosion-proof hole 114, the height of the gap 1113 decreases in the first direction Z. That is, the inclined surface 115 moves closer to the top cover body 1112 from the top to the bottom, so that the height of the gap 1113 decreases. That is, the height of the gap 1113 is the largest near the explosion-proof hole 114. Since the high-temperature substances ejected after the battery cell thermal runaway all need to pass through the explosion-proof hole 114, the temperature at the edge of the explosion-proof hole 114 is relatively high. Setting the gap 1113 at this point to be larger can better achieve the heat insulation effect through the gap 1113, thereby further reducing the risk of thermal runaway fire.

[0104] The gap 1113 surrounds the explosion-proof hole 114. When high temperatures are generated around the explosion-proof hole 114 due to thermal runaway, the gap 1113 surrounding the explosion-proof hole 114 can block the heat from being transferred to the top patch 1111 in all directions, forming a complete heat insulation barrier, thereby further reducing the risk of thermal runaway fire.

[0105] In some embodiments, a heat insulation element is provided in the gap 1113 between the top patch 1111 and the top cover body 1112. In the event of thermal runaway of the battery cell 100, under the high-temperature environment around the explosion-proof hole 114, the heat insulation element can effectively block heat conduction and radiation, confining the heat as much as possible to one side of the top cover body 1112. This greatly reduces the heat transferred to the top patch 1111, further preventing the possibility of the plastic debris accumulated on the top patch 1111 being ignited by molten aluminum beads after overheating, and further reducing the risk of thermal runaway fire. Simultaneously, the heat insulation element in the gap 1113 provides support for the inclined surface 115, preventing the inclined surface 115 from deforming under high temperatures and losing its function of dispersing ejected materials, thus improving the reliability of the slope structure formed by the inclined surface 115.

[0106] The heat insulation component can be filled into the gap 1113, or a prefabricated heat insulation component of matching shape can be placed in the gap 1113. When the gap 1113 is annular around the explosion-proof hole 114, the prefabricated heat insulation component can also be annular to better play the role of heat insulation and support.

[0107] The insulation material can be glass wool, rock wool, ceramic fiber, aerogel, etc., and this disclosure does not impose any restrictions on it.

[0108] In this disclosure, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise expressly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0109] In the description of the embodiments of this disclosure, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this disclosure and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this disclosure.

[0110] In the description of this disclosure, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the implementation of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0111] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

[0112] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

Claims

1. A top cover for an energy storage device, characterized in that, The top cover (111) includes a top surface (112) and a back surface (113) along the first direction (Z), and an explosion-proof hole (114) is formed on the top cover (111) through the top surface (112) and the back surface (113); Wherein, at least a portion of the area surrounding the explosion-proof hole (114) on the top surface (112) is a slope (115), the slope (115) extends along a second direction (X) and / or a third direction (Y) toward the side away from the explosion-proof hole (114), and the slope (115) is inclined toward the back surface (113) in the extending direction; the second direction (X) intersects the first direction (Z), and the third direction (Y) intersects the first direction (Z) and the second direction (X); The inclined surface (115) extends from the edge of the explosion-proof hole (114) toward the side away from the explosion-proof hole (114), and the highest point of the inclined surface (115) is the edge of the explosion-proof hole (114).

2. The top cover according to claim 1, characterized in that, The top cover (111) is larger in the second direction (X) than in the third direction (Y), and the inclined surface (115) extends in the third direction (Y) to the edge of the top cover (111).

3. The top cover according to claim 1, characterized in that, The top cover (111) includes a top patch (1111) and a top cover body (1112), the top patch (1111) and the top cover body (1112) are stacked along the first direction (Z); the surface of the top patch (1111) facing away from the top cover body (1112) along the first direction (Z) is the top surface (112), and the inclined surface (115) is formed on the top patch (1111).

4. The top cover according to claim 3, characterized in that, The top patch (1111) has a gap (1113) between itself and the top cover body (1112) along the first direction (Z) in the region where the inclined surface (115) is formed.

5. The top cover according to claim 3 or 4, characterized in that, The top patch (1111) is a uniform thickness structure along the first direction (Z), at least in the region where the inclined surface (115) is formed.

6. The top cover according to claim 4, characterized in that, Along the second direction (X) and / or the third direction (Y) in the direction away from the explosion-proof hole (114), the height of the gap (1113) decreases in the first direction (Z).

7. The top cover according to claim 4, characterized in that, The gap (1113) surrounds the explosion-proof hole (114).

8. The top cover according to claim 4, characterized in that, A heat insulation element is provided in the gap (1113) between the top patch (1111) and the top cover body (1112).

9. The top cover according to claim 1 or 3, characterized in that, The inclined surface (115) includes a plurality of inclined planes surrounding the explosion-proof hole (114).

10. The top cover according to claim 9, characterized in that, The plurality of inclined planes include a first inclined plane (1151) and a second inclined plane (1152), wherein the first inclined plane (1151) and the second inclined plane (1152) are arranged opposite to each other along the second direction (X) or the third direction (Y).

11. The top cover according to claim 10, characterized in that, The top cover (111) has a larger dimension in the second direction (X) than in the third direction (Y), and the first inclined plane (1151) and the second inclined plane (1152) are arranged opposite to each other along the third direction (Y).

12. The top cover according to claim 9, characterized in that, The plurality of inclined planes include a third inclined plane (1153), a fourth inclined plane (1154), a fifth inclined plane (1155), and a sixth inclined plane (1156). The third inclined plane (1153) and the fourth inclined plane (1154) are arranged opposite each other along the third direction (Y), and the fifth inclined plane (1155) and the sixth inclined plane (1156) are arranged opposite each other along the second direction (X).

13. The top cover according to claim 1 or 3, characterized in that, The inclined surface (115) surrounds the explosion-proof hole (114), and the inclined surface (115) is a continuous curved surface in the direction surrounding the explosion-proof hole (114).

14. The top cover according to claim 3, characterized in that, The bevel (115) on the top patch (1111) is formed by a stamping process.

15. The top cover according to claim 3, characterized in that, The top patch (1111) is provided with a first explosion-proof through hole (1141), and the top cover body (1112) is provided with a second explosion-proof through hole (1142). The first explosion-proof through hole (1141) and the second explosion-proof through hole (1142) communicate to form the explosion-proof hole (114). In the first direction (Z), the orthographic projection of the second explosion-proof through hole (1142) is located within the orthographic projection of the first explosion-proof through hole (1141).

16. A top cover assembly, characterized in that, include: The top cover (111) according to any one of claims 1 to 15; An explosion-proof valve (116) is provided on the explosion-proof hole (114); An insulating element (117) is stacked along the first direction (Z) on one side of the back (113) of the top cover (111).

17. An energy storage device, characterized in that, include: The housing (120) includes a receiving space having an opening (121); An electrode assembly (130) is housed in the receiving space; The top cover assembly (110) of claim 16, the top cover assembly (110) covering the opening (121).

18. An energy storage system, characterized in that, Includes the energy storage device (10) as described in claim 17.

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