Collecting disc, end cover assembly, energy storage device and energy storage system

Abstract

The utility model discloses a collector plate, end cap subassembly, energy storage device and energy storage system, collector plate includes plate body portion and partition boss, plate body portion has its axial opposite first surface and second surface, and plate body portion is provided with first through-hole that runs through first surface and second surface, first surface is provided with first groove, and second surface is provided with second groove. The separation boss and the disc body part are arranged in a split mode, and the separation boss is arranged on the first surface in a protruding mode. Wherein at least part of the first through hole is covered by the separation boss, the first through hole is communicated with the first groove, and at least part of the first groove is exposed out of the separation boss, so that the first groove can be communicated with the explosion-proof hole.

Description

Technical Field

[0001] The utility model relates to the technical field of filters, and in particular to a collecting plate, an end cover assembly, an energy storage device and an energy storage system. Background Art

[0002] When batteries and other energy storage devices fail, they will generate a large amount of gas. If the gas cannot be discharged in time, the battery will explode when it accumulates to a certain amount, endangering personal and property safety. Related technology In order to prevent the battery from exploding due to excessive gas pressure and protect the battery, an explosion-proof valve is usually provided in the end cover assembly of the battery as a safety device, so that it can explode in time when the gas pressure inside the battery reaches a certain value, thereby discharging the gas inside the battery in time.

[0003] However, due to the limited internal space of the battery, it is not conducive to the diffusion of the gas inside the battery, resulting in the inability to discharge the gas inside the battery to the explosion-proof valve in time, which may easily lead to the problem that the explosion-proof valve cannot explode in time. There is a hidden danger that the gas generated inside the battery cannot be released in time, which may easily cause the internal gas pressure of the battery to exceed the critical value and explode, which is very dangerous. Utility Model Content

[0004] The embodiment of the utility model discloses a collecting plate, an end cover assembly, an energy storage device and an energy storage system, which can increase the exhaust area, facilitate the timely explosion-proof valve to explode, reduce the risk of thermal runaway failure, and improve the safe use performance of the energy storage device.

[0005] In order to achieve the above-mentioned objectives, in a first aspect, the utility model discloses a current collecting plate, which includes a plate body and a separation boss, the plate body having a first surface and a second surface opposite to each other along its axial direction, the plate body being provided with a first through hole penetrating the first surface and the second surface, the first surface being provided with a first groove, the separation boss being separately provided with the plate body, and the separation boss being convexly provided on the first surface, wherein at least a portion of the first through hole is covered by the separation boss, and at least a portion of the first groove is exposed from the separation boss, so that the first groove can remain connected with the explosion-proof hole.

[0006] In the current collecting disk provided in the present application, the current collecting disk adopts a disk body and a partition boss which are separately arranged, so that a first through hole and a first groove can be arranged in the disk body, the first through hole is kept through in the axial direction of the disk body, and the first through hole is at least partially covered by the partition boss, and the first through hole is kept in communication with the first groove to form an exhaust channel between the partition boss and the disk body, and the first groove is at least partially exposed to the partition boss and is not blocked by the partition boss, so that when thermal runaway occurs, the gas generated by the battery cell can pass through the first through hole in sequence. The through hole and the first groove discharge to the explosion-proof valve to break through the explosion-proof valve for pressure relief, thereby reducing the internal pressure of the energy storage device. Compared with the method in which the disc body and the partition boss are integrally formed and the partition boss is solid, it is equivalent to adding an additional exhaust channel that can discharge the gas generated by the battery cell to the explosion-proof valve, increasing the exhaust area, so that the gas generated by the battery cell can be discharged to the explosion-proof valve in a timely and rapid manner, so as to ensure that the explosion-proof valve can discharge the gas in time for pressure relief and explosion prevention, thereby reducing the risk of explosion due to thermal runaway failure, and improving the safety of the energy storage device.

[0007] Since the separately arranged disc body and separation boss are simpler in structure than the current collecting disc and the separation boss being integrally formed, the separately arranged disc body and separation boss can reduce the difficulty of product forming, improve product yield and reduce cost.

[0008] As an optional embodiment, in an embodiment of the first aspect of the utility model, a portion of the first groove is covered by the partition boss, and another portion of the first groove is exposed from the partition boss, so that the first groove can be connected to the explosion-proof hole; a second groove is provided on the surface of the partition boss facing the disc body, and the through-hole portion of the first through-hole covered by the partition boss and the groove portion of the first groove covered by the partition boss are connected through the second groove, so that when thermal runaway occurs, the gas generated by the battery cell can be discharged to the explosion-proof valve through the first through-hole, the second groove and the first groove in sequence, so as to break through the explosion-proof valve for pressure relief, thereby reducing the internal pressure of the energy storage device, reducing the risk of explosion due to thermal runaway failure, and improving the safety of the energy storage device.

[0009] The above-mentioned method is adopted to keep the first through hole and the first groove connected. Compared with the first groove extending radially along the disk body to the hole wall surface that passes through the first through hole so as to keep connected with the first through hole, excessive material removal from the disk body is avoided to ensure the structural strength of the disk body. Compared with the method of providing a channel between the first through hole and the first groove so as to connect the first through hole and the first groove, the processing difficulty of the disk body can be reduced, thereby facilitating the processing of the disk body and reducing the processing cost of the disk body.

[0010] As an optional implementation, in an embodiment of the first aspect of the utility model, the partition boss is provided with an injection hole that penetrates along the axial direction of the disk body, the injection hole is connected to the second groove to be connected to the first through hole, and the injection hole is coaxially arranged with the first through hole, and the aperture of the injection hole is smaller than the aperture of the first through hole. During injection, the electrolyte can be injected into the energy storage device through the injection hole and the first through hole, so that the battery cell can be immersed in the electrolyte to ensure the performance of the battery cell, so as to avoid opening an additional through hole in the end cover plate to avoid affecting the structural strength of the end cover plate. At the same time, the injection hole is coaxially arranged with the first through hole, and the aperture of the injection hole is smaller than the aperture of the first through hole, which can ensure that most of the electrolyte injected through the injection hole can enter the energy storage device through the first through hole to soak the battery cell.

[0011] As an optional embodiment, in an embodiment of the first aspect of the utility model, a protrusion is provided on the bottom surface of the second groove facing the disc body, and the injection hole passes through the protrusion along the axial direction of the disc body, and the injection hole is used for the sealing nail to pass through, so that the depth of the injection hole in the axial direction of the disc body can be extended with the help of the protrusion, thereby increasing the contact area between the injection hole and the sealing nail, and further improving the stability of the sealing nail in the injection hole.

[0012] As an optional implementation, in the embodiment of the first aspect of the utility model, the partition boss is provided with an injection hole that penetrates along the axial direction of the disk body, the injection hole is connected to the first through hole, and the injection hole and the first through hole are coaxially arranged, and the aperture of the injection hole is smaller than the aperture of the first through hole. During injection, the electrolyte can be injected into the energy storage device through the injection hole and the first through hole, so that the battery cell can be immersed in the electrolyte to ensure the performance of the battery cell, so as to avoid opening an additional through hole in the end cover plate to avoid affecting the structural strength of the end cover plate. At the same time, the injection hole is coaxially arranged with the first through hole, and the aperture of the injection hole is smaller than the aperture of the first through hole, which can ensure that most of the electrolyte injected through the injection hole can enter the energy storage device through the first through hole to soak the battery cell.

[0013] As an optional implementation, in the embodiment of the first aspect of the utility model, the first groove is arranged to extend radially along the disc body, and the depth of the first groove in the axial direction of the disc body is 0.2mm-0.4mm, and the length of the first groove in the circumferential direction of the disc body is 6mm-10mm. When the first groove meets the above-mentioned dimensional relationship, a larger exhaust channel can be formed between the separation boss and the disc body, increasing the flow rate of the gas, so that the gas can be quickly discharged when the battery cell is out of control, and the gas pressure can be released in time to prevent the internal gas pressure of the energy storage device from being too high, thereby facilitating the improvement of the safety and reliability of the energy storage device.

[0014] As an optional implementation, in an embodiment of the first aspect of the utility model, the first through hole and the disc body are coaxially arranged, and there are multiple first grooves, each of which is extended radially along the disc body. In this way, the disc body can maintain its own structural symmetry to ensure the structural stability of the disc body, while further increasing the exhaust channel and further increasing the exhaust area, so that the gas generated by the battery cell can be discharged to the explosion-proof valve faster to ensure that the explosion-proof valve can discharge the gas in time for pressure relief and explosion prevention, thereby greatly reducing the risk of explosion due to thermal runaway failure, and further improving the safety of the energy storage device.

[0015] As an optional implementation, in the embodiment of the first aspect of the utility model, the disk body is also provided with an exhaust hole penetrating the first surface and the second surface, so that the exhaust hole can be used to further increase the flow path of gas to the explosion-proof valve, which is more conducive to quickly discharge the gas when the battery cell is out of control, timely gas pressure relief, and prevent the internal air pressure of the energy storage device from being too high, thereby helping to improve the safety and reliability of the energy storage device.

[0016] As an optional implementation, in an embodiment of the first aspect of the utility model, a reinforcing rib is convexly provided on the first surface, and a limiting groove is formed between the reinforcing rib and the first surface, and the separating boss is arranged in the limiting groove, so that the reinforcing rib can be utilized to improve the structural strength of the disk body so that the disk body is not easily deformed, and the limiting groove can also be utilized to play a certain limiting and positioning role on the separating boss, so as to facilitate the installation of the separating boss.

[0017] In the second aspect, the utility model discloses an end cover assembly, the end cover assembly includes an end cover plate, an explosion-proof valve and a current collecting disk as described in the first aspect above, the end cover plate is provided with an explosion-proof hole penetrating along the axial direction of the disk body, the explosion-proof valve is arranged in the explosion-proof hole, the separation boss of the current collecting disk abuts against the end cover plate, so that the end cover plate is spaced apart from the disk body, so as to define a pressure relief channel connected to the first groove between the end cover plate and the disk body, and the pressure relief channel is connected to the explosion-proof hole. The end cover assembly with the current collecting disk described in the first aspect above can also increase the exhaust area, facilitate the explosion-proof valve to explode in time, reduce the risk of thermal runaway failure, and improve the safe use performance of the energy storage device.

[0018] As an optional embodiment, in an embodiment of the second aspect of the utility model, the end cover plate is also provided with a second through hole extending axially through the disk body, the second through hole comprising a first hole section and a second hole section connected in the axial direction of the disk body, the aperture of the first hole section being larger than the aperture of the second hole section to form a step surface; the first end of the partition boss away from the disk body is embedded in the second hole section and extends to be located in the first hole section, the first end being welded to the step surface; the end cover assembly also includes a sealing sheet, the sealing sheet is arranged in the first hole section and abuts against the step surface to seal the injection hole on the partition boss, and a positioning groove is provided on the surface of the sealing sheet facing the step surface, the first end is embedded in the positioning groove.

[0019] Through the above design, while the sealing sheet is set in the first hole section to position the sealing sheet, the first end of the dividing boss can be extended into the sealing sheet, so that the sealing sheet can be double-positioned to facilitate the installation of the sealing sheet. At the same time, since one of the re-positioning effects of the sealing sheet is achieved by utilizing the cooperation between the first end of the dividing boss and the positioning groove, there is no need to additionally set up a positioning column and the positioning groove, thereby simplifying the structure of the end cover assembly to facilitate the processing and formation of the end cover assembly.

[0020] In the third aspect, the utility model discloses an energy storage device, the energy storage device comprises a shell, a battery cell and an end cover assembly as described in the second aspect, the shell having a receiving cavity and an opening connected to the receiving cavity, the battery cell being built in the receiving cavity, the end cover plate being sealed at the opening, and the disc body of the current collecting disc being welded to the battery cell. The energy storage device having the end cover assembly as described in the second aspect, since the end cover assembly has the same or similar beneficial effects as the current collecting disc as described in the first aspect, the energy storage device having the end cover assembly as described in the second aspect can also increase the exhaust area, facilitate the explosion-proof valve to explode in time, reduce the risk of thermal runaway failure, and improve the safe use performance of the energy storage device.

[0021] In a fourth aspect, the utility model discloses an energy storage system, which has an energy storage device as described in the third aspect. Since the energy storage device has the same or similar beneficial effects as the collector plate described in the first aspect, the energy storage system having the energy storage device described in the third aspect can also increase the exhaust area, facilitate the explosion-proof valve to explode in time, reduce the risk of thermal runaway failure, and improve the safe use performance of the energy storage device.

[0022] Compared with the prior art, the beneficial effects of the utility model are:

[0023] The collector plate, end cover assembly, energy storage device and energy storage system provided by the embodiment of the utility model adopt a disc body and a partition boss which are separately arranged on the collector plate, so that a first through hole and a first groove can be arranged on the disc body, the first through hole is kept through in the axial direction of the disc body, and at least a part of the first through hole is covered by the partition boss, and the first through hole is kept in communication with the first groove to form an exhaust passage between the partition boss and the disc body, and at least a part of the first groove is exposed to the partition boss and is not blocked by the partition boss, so that when thermal runaway occurs, The gas generated by the battery cell can be discharged to the explosion-proof valve through the first through hole and the first groove in sequence, so as to break through the explosion-proof valve for pressure relief. Compared with the method in which the disc body and the partition boss are integrally formed and the partition boss is solid, it is equivalent to adding an additional exhaust channel that can discharge the gas generated by the battery cell to the explosion-proof valve, thereby increasing the exhaust area, so that the gas generated by the battery cell can be discharged to the explosion-proof valve in a timely and rapid manner, so as to ensure that the explosion-proof valve can discharge the gas in time for pressure relief and explosion prevention, thereby reducing the risk of explosion due to thermal runaway failure and improving the safety of the energy storage device.

[0024] Since the separately arranged disc body and separation boss are simpler in structure than the current collecting disc and the separation boss being integrally formed, the separately arranged disc body and separation boss can reduce the difficulty of product forming, improve product yield and reduce cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 This is a schematic diagram of the first structure of the energy storage system disclosed in the embodiment of the utility model;

[0027] Figure 2 This is a second structural schematic diagram of the energy storage system disclosed in the embodiment of the utility model;

[0028] Figure 3 It is a schematic diagram of the exploded structure of the energy storage device disclosed in the embodiment of the utility model;

[0029] Figure 4 It is a schematic diagram of the exploded structure of the end cover assembly disclosed in the embodiment of the utility model;

[0030] Figure 5 It is a front view structural schematic diagram of the end cover assembly disclosed in the embodiment of the utility model;

[0031] Figure 6 yes Figure 5 A cross-sectional view of the end cover assembly along the AA direction;

[0032] Figure 7 yes Figure 6 Schematic diagram of the decomposition of

[0033] Figure 8 yes Figure 7 A local enlarged view of the M in FIG.

[0034] Fig. 9 It is a schematic diagram of the exploded structure of the current collecting plate disclosed in the embodiment of the utility model;

[0035] Fig.10 It is a front view structural schematic diagram of the current collecting plate disclosed in the embodiment of the utility model;

[0036] Fig.11 yes Fig.10 Cross-sectional view of the collecting plate along direction BB.

[0037] Description of main reference numerals

[0038] 1000-Energy storage system;

[0039] 100-energy storage device; 1-housing; 11-accommodating cavity; 12-opening; 2-battery core; 3-end cover assembly; 31-end cover plate; 311-explosion-proof hole; 312-second through hole; 3121-first hole section; 3122-second hole section; 3123-step surface; 32-explosion-proof valve; 33-collecting plate; 331-plate body; 331a-first surface; 331b-second surface; 3311-first through hole; 3312-first groove; 3313-exhaust hole; 33 14-reinforcement rib; 3315-limiting groove; 332-separating boss; 332a-first boss; 332a1-first end; 332b-second boss; 3321-second groove; 3322-liquid injection hole; 3322a-first liquid injection hole section; 3322b-second liquid injection hole section; 3322c-step surface; 3323-protrusion; 34-pressure relief channel; 35-sealing nail; 351-head; 352-main body; 36-sealing sheet; 361-positioning groove;

[0040] 200-electric energy conversion device; 300-first user load; 400-second user load;

[0041] 210 - high voltage cable; 310 - first electric energy conversion device; 410 - second electric energy conversion device. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0044] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first surface may be referred to as a second surface, and similarly, a second surface may be referred to as a first surface. Both the first surface and the second surface are surfaces, but they are not the same surface.

[0045] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission with each other.

[0046] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0047] Since the energy people need is highly temporal and spatial, in order to rationally utilize energy and improve energy utilization, it is necessary to use a medium or device to store one form of energy in the same form or convert it into another form of energy, and then release it in a specific form of energy based on future application needs. As we all know, the main way to generate green electricity is to develop green energy such as photovoltaics and wind power to replace fossil energy.

[0048] At present, the generation of green electricity generally relies on photovoltaics, wind power, and hydropower, etc. However, wind and solar energy generally have problems of strong intermittency and large volatility, which will cause instability of the power grid, insufficient electricity during peak hours, and too much electricity during valley hours. Unstable voltage will also cause damage to electricity. Therefore, insufficient electricity demand or insufficient grid acceptance capacity may cause the problem of "abandoning wind and light". To solve these problems, we must rely on energy storage, that is, converting electrical energy into other forms of energy through physical or chemical means and storing it, and converting energy into electrical energy when needed. In simple terms, energy storage is similar to a large "power bank". When photovoltaic and wind energy are sufficient, electrical energy is stored and the stored electricity is released when needed.

[0049] Taking electrochemical energy storage as an example, an embodiment of the present application provides an energy storage device, in which a group of energy storage batteries are provided. The energy storage device mainly utilizes the chemical elements in the battery as the energy storage medium. The charging and discharging process is accompanied by the chemical reaction or change of the energy storage medium. Simply put, the electric energy generated by wind energy and solar energy is stored in the chemical battery. When the use of external electric energy reaches a peak, the stored electricity is released for use, or transferred to a place where electricity is scarce for use.

[0050] At present, energy storage (i.e. energy storage) has a wide range of application scenarios, including power generation side energy storage, grid side energy storage, renewable energy grid-connected energy storage and user side energy storage. The corresponding types of energy storage devices include:

[0051] ① Large energy storage containers used in grid-side energy storage scenarios can serve as high-quality active and reactive power regulation power sources in the grid, achieve load matching of electric energy in time and space, enhance the ability to absorb renewable energy, and are of great significance in grid system backup, relieving peak load power supply pressure, and peak and frequency regulation;

[0052] ② The main operating mode of small and medium-sized energy storage cabinets used in industrial and commercial energy storage scenarios (banks, shopping malls, etc.) on the user side and small household energy storage boxes used in home energy storage scenarios on the user side is "peak shaving and valley filling". Since there is a large price difference in electricity charges at peak and valley locations according to electricity demand, after users have energy storage equipment, in order to reduce costs, they usually charge the energy storage cabinets / boxes during the low electricity price period; during the peak electricity price period, the electricity in the energy storage equipment is discharged for use to achieve the purpose of saving electricity bills. In addition, in remote areas, as well as areas prone to natural disasters such as earthquakes and hurricanes, the existence of household energy storage devices is equivalent to users providing themselves and the power grid with backup power, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0053] See also Figure 1 , Figure 1 The energy storage system provided in one embodiment of the present application is a schematic diagram of a household energy storage system, and the present application Figure 1The embodiment is described by taking the household energy storage scenario in the user-side energy storage as an example, and the energy storage device provided in the embodiment of the present application is not limited to the household energy storage scenario.

[0054] like Figure 1 As shown, the energy storage system 1000 provided in the embodiment of the present application includes an energy storage device 100 and an electric energy conversion device 200 (photovoltaic panel), a first user load 300 (street lamp), and a second user load 400 (such as air conditioner and other household appliances, etc.). The energy storage device 100 is a small energy storage box that can be mounted on an outdoor wall by wall hanging. Specifically, the photovoltaic panel can convert solar energy into electric energy during the period of low electricity price. The energy storage device 100 is used to store the electric energy and supply it to street lamps and household appliances for use during the peak electricity price, or to supply power when the power grid is off / power outage.

[0055] See also Figure 2 , Figure 2 This is a schematic diagram of the structure of an energy storage system provided in another embodiment of the present application, and the present application Figure 2 The embodiment is described by taking the shared energy storage scenario on the power generation / distribution side as an example, and the energy storage device 100 of the present application is not limited to the energy storage scenario on the power generation / distribution side.

[0056] like Figure 2 As shown, the energy storage system 1000 provided in the embodiment of the present application includes an energy storage device 100, a high-voltage cable 210, a first electric energy conversion device 310 and a second electric energy conversion device 410. In the case of power generation, the first electric energy conversion device 310 and the second electric energy conversion device 410 are used to convert other forms of energy into electric energy, connect to the high-voltage cable 210 and supply it to the power distribution network for use. When the power load is low and the first electric energy conversion device 310 and the second electric energy conversion device 410 generate excess power, the excess power is stored in the energy storage device 100, thereby reducing the wind and solar power abandonment rates and improving the problem of new energy power generation and consumption. When the power load is high, the power grid issues an instruction to transmit the power stored in the energy storage device 100 in conjunction with the high-voltage cable 210 in a grid-connected mode to the power consumption side, providing peak shaving, frequency regulation, standby and other services for the power grid operation, giving full play to the peak shaving role of the power grid, promoting peak shaving and valley filling of the power grid, and alleviating the power supply pressure of the power grid.

[0057] Optionally, the first electric energy conversion device 310 and the second electric energy conversion device 410 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy and mechanical energy into electric energy.

[0058] In the present application, the number of energy storage devices 100 can be multiple, and multiple energy storage devices 100 are connected in series or in parallel. Multiple energy storage devices 100 are supported and electrically connected by isolation plates (not shown). In this embodiment, "multiple" refers to two or more. An energy storage box can also be provided outside the energy storage device 100 to accommodate the energy storage device 100.

[0059] Optionally, the energy storage device 100 may include but is not limited to a single cell, a battery module, a battery pack, a battery system, etc. The actual application form of the energy storage device 100 provided in the embodiment of the present application may be but is not limited to the listed products, and may also be other application forms. The embodiment of the present application does not strictly limit the application form of the energy storage device 100. The embodiment of the present application only takes the energy storage device 100 as a multi-core battery as an example for explanation. When the energy storage device 100 is a single cell, the energy storage device 100 may be at least one of a cylindrical battery, a square battery, etc.

[0060] The technical solution of the present application is further described in detail below by taking the energy storage device 100 as a single battery as an example.

[0061] See also Figure 3 , the energy storage device 100 provided in the embodiment of the present application includes a shell 1, a battery cell 2 and an end cover assembly 3. The shell has a housing 11 and an opening 12 connected to the housing 11, the battery cell 2 is built in the housing 11, and the end cover assembly 3 is sealed at the opening 12 of the shell to seal the battery cell 2 in the housing 11 of the shell. Among them, the battery cell 2 can be one or more. When there are multiple battery cells 2, the multiple battery cells 2 can be arranged along the length direction of the energy storage device 100, or along the width direction of the energy storage device 100, or in an array along the length direction and width direction of the energy storage device 100. And the multiple battery cells 2 can be connected in series or in parallel, or some of the battery cells 2 can be connected in series, and other parts of the battery cells 2 can be connected in parallel.

[0062] See also Figure 3 and Figure 4 The end cover assembly 3 provided in the embodiment of the present application includes an end cover plate 31, an explosion-proof valve 32 and a current collecting plate 33. The end cover plate 31 is sealed at the opening 12, and the end cover plate 31 is provided with an explosion-proof hole 311 penetrating along the axial direction of the end cover plate 31. The explosion-proof valve 32 is arranged in the explosion-proof hole 311, so that when the internal pressure value of the shell is greater than the set explosion-proof pressure value of the explosion-proof valve 32, the explosion-proof valve 32 opens in time by sensing the change in the internal air pressure of the shell to exhaust and release the pressure, so as to avoid the risk of explosion or fire of the energy storage device 100, thereby improving the safety performance of the energy storage device 100. The current collecting plate 33 is electrically connected between the end cover plate 31 and the battery cell 2 to output the current inside the battery cell 2 to the energy storage device 100. Among them, the axial direction of the end cover plate 31 is parallel to the height direction of the energy storage device 100, for example Figure 3 The up and down directions in .

[0063] See also Figures 5 to 7 The collecting plate 33 provided in the embodiment of the present application includes a plate body 331 and a separation boss 332. The plate body 331 has a first surface 331a and a second surface 331b opposite to each other along its axial direction. The separation boss 332 is convexly arranged on the first surface 331a, and the separation boss 332 abuts against the end cover plate 31, so that the end cover plate 31 is spaced apart from the plate body 331, so as to define a pressure relief channel 34 connected to the explosion-proof hole 311 between the end cover plate 31 and the plate body 331. The axial direction of the plate body 331 is parallel to the axial direction of the end cover plate 31.

[0064] It should be known that during the use of the energy storage device 100, thermal runaway may occur due to various reasons. When the energy storage device 100 experiences thermal runaway, the intensity of the thermal runaway reaction may vary. When the thermal runaway reaction of the energy storage device 100 is relatively mild, a small amount of gas may be generated inside the battery cell 2, causing the internal pressure of the energy storage device 100 to increase. However, due to the limited internal space of the battery, the gas cannot be discharged in time, resulting in continuous accumulation of internal pressure of the battery, which may cause an explosion risk. In addition, the thermal runaway reaction of the energy storage device 100 may be relatively severe. At this time, a large amount of gas will be generated inside the battery cell 2 in a short period of time. If the gas inside the energy storage device 100 cannot be discharged in time, there is a great safety hazard.

[0065] When the energy storage device 100 has thermal runaway and the thermal runaway reaction is relatively mild, the gas generated by the battery cell 2 can enter the pressure relief channel 34. Since there is a certain space in the pressure relief channel 34, the small amount of gas generated by the battery cell 2 can be dispersed in the space of the pressure relief channel 34, thereby ensuring that the pressure inside the energy storage device 100 is maintained at a low level, thereby avoiding the safety hazard caused by excessive pressure inside the energy storage device 100. When the thermal runaway reaction is more intense, a large amount of gas is generated inside the battery cell 2 in a short period of time. After the gas enters the pressure relief channel 34, the pressure inside the energy storage device 100 continues to rise. When the pressure is higher than the set threshold of the explosion-proof valve 32, the explosion-proof valve 32 on the end cover plate 31 opens, and the gas can be discharged from the opening 12 of the explosion-proof valve 32 to reduce the internal pressure of the energy storage device 100 and improve the safety of the energy storage device 100.

[0066] See also Figures 6 to 9 The separation boss 332 in the present application is separately provided with the disk body 331 , and the disk body 331 is provided with a first through hole 3311 penetrating the first surface 331a and the second surface 331b , and the first surface 331a is provided with a first groove 3312 .

[0067] Among them, the first through hole 3311 is at least partially covered by the partition boss 332, that is, the entire first through hole 3311 can be covered by the partition boss 332, or a part of the first through hole 3311 is covered by the partition boss 332, and the other part is exposed from the partition boss 332 and not covered by the partition boss 332. At least a portion of the first groove 3312 is exposed on the partition boss 332, that is, the entire first groove 3312 can be exposed on the partition boss 332 and not covered by the partition boss 332, or a portion of the first groove 3312 is covered by the partition boss 332, and the other portion is exposed on the partition boss 332 and not covered by the partition boss 332, so that the first groove 3312 can maintain communication with the explosion-proof hole 311, so that when the battery cell 2 has thermal runaway, the gas generated by the battery cell 2 can enter the pressure relief channel 34 through the first through hole 3311 and the first groove 3312 in sequence and be discharged to the explosion-proof valve 32, so as to break through the explosion-proof valve 32 for pressure relief. In addition, the internal pressure of the energy storage device 100 is reduced. Compared with the method in which the disc body 331 and the partition boss 332 are integrally formed and the partition boss 332 is solid, it is equivalent to adding an additional exhaust channel that can discharge the gas generated by the battery cell 2 to the pressure relief channel 34, that is, it is equivalent to adding an additional exhaust channel that can discharge the gas generated by the battery cell 2 to the explosion-proof valve 32, which increases the exhaust area, so that the gas generated by the battery cell 2 can be discharged to the explosion-proof valve 32 in a timely and rapid manner, so as to ensure that the explosion-proof valve 32 can discharge the gas in time for pressure relief and explosion prevention, thereby reducing the risk of explosion due to thermal runaway failure, and improving the safety of the energy storage device 100.

[0068] Since the separately arranged disc body 331 and the separating boss 332 are simpler in structure than the collecting disc 33 and the separating boss 332 which are integrally formed, the separately arranged disc body 331 and the separating boss 332 can reduce the difficulty of product forming, improve product yield and reduce costs.

[0069] In some optional embodiments, a portion of the first groove 3312 is covered by the partition boss 332, and another portion of the first groove 3312 is exposed on the partition boss 332 and is not covered by the partition boss 332, so that the first groove 3312 can maintain communication with the explosion-proof hole 311; the second groove 3321 is provided on the surface of the partition boss 332 facing the disc body 331, and the through-hole portion of the first through hole 3311 covered by the partition boss 332 and the groove portion of the first groove 3312 covered by the partition boss 332 are maintained in communication through the second groove 3321, so that when thermal runaway occurs in the battery cell 2, the gas generated by the battery cell 2 can enter the pressure relief channel 34 through the first through hole 3311, the second groove 3321 and the first groove 3312 in sequence and be discharged to the explosion-proof valve 32, so as to break through the explosion-proof valve 32 for pressure relief, thereby reducing the internal pressure of the energy storage device 100, reducing the risk of explosion due to thermal runaway failure, and improving the safety of the energy storage device 100.

[0070] In some optional embodiments, the partition boss 332 is provided with a liquid injection hole 3322 penetrating along the axial direction of the disc body 331, and the liquid injection hole 3322 is communicated with the first through hole 3311. When the second groove 3321 is provided on the surface of the partition boss 332 facing the disc body 331, the liquid injection hole 3322 is communicated with the second groove 3321 to communicate with the first through hole 3311, that is, the liquid injection hole 3322 can be communicated with the first through hole 3311 through the second groove 3321, and the liquid injection hole 3322 is coaxially arranged with the first through hole 3311, and the aperture of the liquid injection hole 3322 is smaller than the aperture of the first through hole 3311. During injection, the electrolyte can be injected into the energy storage device 100 through the injection hole 3322 and the first through hole 3311, so that the battery cell 2 can be immersed in the electrolyte to ensure the performance of the battery cell 2. In this way, it is possible to avoid opening an additional through hole in the end cover plate 31 to avoid affecting the structural strength of the end cover plate 31. At the same time, the injection hole 3322 is coaxially arranged with the first through hole 3311, and the aperture of the injection hole 3322 is smaller than the aperture of the first through hole 3311, which can ensure that most of the electrolyte injected through the injection hole 3322 can enter the energy storage device 100 through the first through hole 3311 to soak the battery cell 2.

[0071] After the injection is completed, the injection hole 3322 is used for the sealing nail 35 to penetrate, so that the sealing nail 35 can be used to seal the injection hole 3322 to ensure that the battery cell 2 can be placed in a sealed cavity after the injection is completed.

[0072] Optionally, combined Figures 6 to 8As shown, the injection hole 3322 may include a first injection hole section 3322a and a second injection hole section 3322b connected in the axial direction of the disc body 331, the aperture of the first injection hole section 3322a is larger than the aperture of the second injection hole section 3322b, so as to form a stepped surface 3322c, and the sealing nail 35 includes a head 351 and a main body 352 connected in the axial direction of the disc body 331, the radial dimension of the head 351 is larger than the radial dimension of the main body 352, and the main body 35 2 is penetrated in the second liquid injection hole section 3322b, and the head 351 is penetrated in the first liquid injection hole section 3322a and abuts against the stepped surface 3322c, so as to prevent the sealing nail 35 from being separated from the liquid injection hole 3322 in the direction toward the battery cell 2, and at the same time, it can also prevent the sealing nail 35 from protruding out of the liquid injection hole 3322 and being located outside the liquid injection hole 3322, so as to prevent the sealing nail 35 from being loosened due to accidental contact with the sealing nail 35, so as to ensure the sealing effect of the sealing nail 35 on the liquid injection hole 3322.

[0073] In order to further improve the sealing performance of the sealing nail 35 in the injection hole 3322, the end cover assembly 3 also includes a sealing sheet 36, which is arranged on the side of the end cover plate 31 facing away from the collecting plate 33, and the sealing sheet 36 covers the sealing nail 35, so that the sealing sheet 36 can further seal the injection hole 3322.

[0074] Optionally, the present application may weld the sealing pins to the end cover plate 31 by welding, so as to achieve a sealed connection between the sealing sheet 36 and the end cover plate 31 .

[0075] In some optional embodiments, a protrusion 3323 is provided on the bottom surface of the second groove 3321 facing the disk body 331, and the injection hole 3322 passes through the protrusion 3323 along the axial direction of the disk body 331. In this way, the protrusion 3323 can be used to extend the depth of the injection hole 3322 in the axial direction of the disk body 331, thereby increasing the contact area between the injection hole 3322 and the sealing nail 35, thereby improving the stability of the sealing nail 35 in the injection hole 3322.

[0076] In some optional embodiments, such as Fig. 9 As shown, the first through hole 3311 and the disc body 331 are coaxially arranged, and there are multiple first grooves 3312, each of which is extended radially along the disc body 331. In this way, the disc body 331 can maintain its own structural symmetry to ensure the structural stability of the disc body 331, while further increasing the exhaust channel and further increasing the exhaust area, so that the gas generated by the battery cell can be discharged to the explosion-proof valve more quickly, so as to ensure that the explosion-proof valve can discharge the gas in time for pressure relief and explosion prevention, thereby greatly reducing the risk of explosion due to thermal runaway failure, and further improving the safety of the energy storage device.

[0077] Furthermore, since the first through hole 3311 and the disk body 331 are coaxially arranged, and it can be seen from the above that the injection hole 3322 and the first through hole 3311 are coaxially arranged, the injection hole 3322 can be located at the center of the disk body 331. When injecting liquid, pouring electrolyte from the center can make the energy storage device have a higher injection efficiency. The electrolyte flows into the center of the battery cell, which can improve the wetting efficiency of the battery cell.

[0078] In some optional embodiments, combined with Figures 6 to 8 As shown, the end cover plate 31 is further provided with a second through hole 312 penetrating along the axial direction of the disk body 331, and the first end 332a1 of the partition boss 332 away from the disk body 331 is embedded in the second through hole 312, and the first end 332a1 of the partition boss 332 facing away from the disk body 331 is welded to the surface of the end cover plate 31 facing away from the disk body 331, that is, when welding, the first end 332a1 of the partition boss 332 away from the disk body 331 is extended into the first end 332a1 of the partition boss 332 The first end 332a1 of the partition boss 332 away from the disk body 331 can be welded to the surface of the end cover plate 31 facing away from the disk body 331, thereby realizing the electrical connection between the current collecting plate 33 and the end cover plate 31. In this way, the current collecting plate 33 in the present application does not need to be bent. Compared with the bent current collecting plate 33, the problem that the bent current collecting plate 33 is prone to breakage due to repeated vibrations can be solved, thereby helping to improve the service life of the current collecting plate 33. At the same time, since the first end 332a1 of the partition boss 332 away from the disk body 331 can be extended into the through hole, the first end 332a1 of the partition boss 332 away from the disk body 331 can be welded to the surface of the end cover plate 31 facing away from the disk body 331, so that laser welding can be used between the second through hole 312 and the first end 332a1. Compared with the penetration welding method, the welding speed is faster and the welding efficiency is higher.

[0079] In addition, extending the first end 332a1 of the collecting plate 33 into the end cover plate 31 can increase the contact area between the collecting plate 33 and the end cover plate 31 while positioning the end cover plate 31. The larger the contact area, the lower the resistance, thereby reducing the internal resistance of the energy storage device and improving the charging and discharging performance of the energy storage device.

[0080] Furthermore, the second through hole 312 includes a first hole section 3121 and a second hole section 3122 which are connected in the axial direction of the disk body 331, and the aperture of the first hole section 3121 is larger than the aperture of the second hole section 3122 to form a step surface 3123; the first end 332a1 of the separating boss 332 away from the disk body 331 is embedded in the second hole section 3122 and extends to the first hole section 3121, and the first end 332a1 is welded to the step surface 3123; the sealing sheet 36 is arranged in the first hole section 3121 and abuts against the step surface 3123 to seal the injection hole 3322 on the separating boss 332, and the surface of the sealing sheet 36 facing the step surface 3123 is provided with a positioning groove 361, and the first end 332a1 is embedded in the positioning groove 361. Through the above design, while the sealing sheet 36 is set in the first hole section 3121 to position the sealing sheet 36, the first end 332a1 of the dividing boss 332 can be extended into the sealing sheet 36, so that the sealing sheet 36 can be double-positioned to facilitate the installation of the sealing sheet 36. At the same time, since one of the re-positioning effects of the sealing sheet 36 is achieved by utilizing the cooperation between the first end 332a1 of the dividing boss 332 and the positioning groove 361, there is no need to additionally set a positioning column to cooperate with the positioning groove 361, thereby simplifying the structure of the end cover assembly 3 to facilitate the processing and formation of the end cover assembly 3.

[0081] Exemplarily, the separating boss 332 includes a first boss 332a and a second boss 332b connected in the axial direction of the disk body 331, the radial dimension of the first boss 332a is smaller than the radial dimension of the second boss 332b, and the first boss 332a is embedded in the second hole section 3122, and the first end 332a1 is formed on the first boss 332a, the second boss 332b is located outside the second hole section 3122 and connected to the disk body 331, and the second boss 332b is also abutted against the end cover plate 31 to space the end cover plate 31 from the disk body 331, thereby defining a pressure relief channel 34 connected to the explosion-proof hole 311 between the end cover plate 31 and the disk body 331.

[0082] In some optional embodiments, such as Fig. 9As shown, the first groove 3312 is extended radially along the disk body 331, and the depth of the first groove 3312 in the axial direction of the disk body 331 can be 0.2mm-0.4mm, that is, along the axial direction of the disk body 331, the distance between the surface of the separating boss 332 facing the disk body 331 and the bottom surface of the first groove 3312 is 0.2mm-0.4mm, for example, 0.2mm, 0.22mm, 0.25mm, 0.28mm, 0.3mm, 0.33mm, 0.35mm, 0.37mm, 0.39mm or 0.4mm, etc., and the length of the first groove 3312 in the circumferential direction of the disk body 331 can be 6mm-10mm, for example, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm or 10mm, etc. When the first groove 3312 satisfies the above-mentioned size relationship, a larger exhaust channel can be formed between the separation boss 332 and the disk body 331, thereby increasing the flow rate of the gas, so that the gas can be quickly discharged when the battery cell 2 is out of control, and the gas pressure can be released in time to prevent the internal gas pressure of the energy storage device from being too high, which is beneficial to improving the safety and reliability of the energy storage device.

[0083] In some optional embodiments, combined with Figures 9 to 11 As shown, the disc body 331 is further provided with an exhaust hole 3313 penetrating the first surface 331a and the second surface 331b. By providing the exhaust hole 3313, the flow path of the gas to the explosion-proof valve can be further increased, so that it is more conducive to quickly draining the gas when the battery cell is out of control, timely releasing the gas pressure, preventing the internal gas pressure of the energy storage device from being too high, and thus helping to improve the safety and reliability of the energy storage device.

[0084] Optionally, there are multiple exhaust holes 3313, and the multiple exhaust holes 3313 can be distributed at intervals along the circumference of the disc body 331, and each exhaust hole 3313 is located between two adjacent first grooves 3312, and each exhaust hole 3313 is a heat dissipation hole structure with a completely hollow interior, rather than an exhaust structure with a plurality of staggered ribs inside to divide the interior into a plurality of small holes, nor an exhaust structure formed by a plurality of small holes arranged at intervals. In this way, each exhaust hole 3313 can have a larger exhaust area, thereby increasing the area of ​​the gas pressure relief channel, and can discharge the gas to the explosion-proof valve more quickly, and perform gas pressure relief in time, thereby further improving the safety and reliability of the energy storage device.

[0085] In some optional embodiments, a reinforcing rib 3314 is convexly provided on the first surface 331a of the disk body 331, and a limiting groove 3315 is formed between the reinforcing rib 3314 and the first surface 331a. The separating boss 332 is arranged in the limiting groove 3315, so that the reinforcing rib can be utilized to improve the structural strength of the disk body 331, so that the disk body 331 is not easily deformed, and the limiting groove 3315 can also be utilized to play a certain limiting and positioning role on the separating boss 332, so as to facilitate the installation of the separating boss 332.

[0086] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0087] In addition, the above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the content of this specification should not be understood as limiting the present application, and the protection scope of the present application shall be subject to the attached claims.

Claims

1. A collecting plate, characterized in that: Applied to an end cover assembly, the end cover assembly is provided with an explosion-proof hole for installing an explosion-proof valve, and the collecting plate comprises: a disc body, the disc body having a first surface and a second surface opposite to each other in the axial direction thereof, the disc body being provided with a first through hole penetrating the first surface and the second surface, and the first surface being provided with a first groove; and A separation boss, the separation boss is separately provided with the disc body, and the separation boss is convexly provided on the first surface; The first through hole is at least partially covered by the partition boss, and the first through hole is connected to the first groove, and the first groove is at least partially exposed from the partition boss, so that the first groove can be connected to the explosion-proof hole.

2. The collecting plate according to claim 1, characterized in that: A portion of the first groove is covered by the partition boss, and another portion of the first groove is exposed from the partition boss, so that the first groove can maintain communication with the explosion-proof hole; A second groove is provided on the surface of the partition boss facing the disk body, and a through hole portion of the first through hole covered by the partition boss and a groove portion of the first groove covered by the partition boss are connected through the second groove.

3. The collecting plate according to claim 2, characterized in that: The partition boss is provided with an injection hole which penetrates axially along the disc body, the injection hole is connected with the second groove to be connected with the first through hole, and the injection hole is coaxially arranged with the first through hole, and the aperture of the injection hole is smaller than the aperture of the first through hole.

4. The collecting plate according to claim 3, characterized in that: The second groove is provided with a protruding portion on the groove bottom surface facing the disc body, the injection hole penetrates the protruding portion along the axial direction of the disc body, and the injection hole is used for the sealing nail to pass through.

5. The collecting plate according to claim 1, characterized in that: The partition boss is provided with a liquid injection hole which penetrates the disk body in the axial direction, the liquid injection hole is communicated with the first through hole, and the liquid injection hole is coaxially arranged with the first through hole, and the aperture of the liquid injection hole is smaller than the aperture of the first through hole.

6. The current collecting plate according to any one of claims 1 to 5, characterized in that: The first groove is extended along the radial direction of the disc body, and the depth of the first groove in the axial direction of the disc body is 0.2 mm-0.4 mm, and the length of the first groove in the circumferential direction of the disc body is 6 mm-10 mm.

7. The current collecting plate according to any one of claims 1 to 5, characterized in that: The first through hole and the disk body are coaxially arranged, and there are a plurality of first grooves, each of which is extended along the radial direction of the disk body.

8. The current collecting plate according to any one of claims 1 to 5, characterized in that: The disk body is also provided with an exhaust hole penetrating through the first surface and the second surface.

9. The current collecting plate according to any one of claims 1 to 5, characterized in that: The first surface is provided with a reinforcing rib, and a limiting groove is formed between the reinforcing rib and the first surface, and the separating boss is arranged in the limiting groove.

10. An end cap assembly, characterized in that: The end cover assembly includes an end cover plate, an explosion-proof valve and a current collecting disc as described in any one of claims 1 to 9, the end cover plate being provided with an explosion-proof hole penetrating axially along the disc body, the explosion-proof valve being arranged in the explosion-proof hole, the partition boss of the current collecting disc abutting against the end cover plate to space the end cover plate from the disc body so as to define a pressure relief channel between the end cover plate and the disc body, the pressure relief channel being respectively connected to the first groove and the explosion-proof hole.

11. The end cap assembly according to claim 10, characterized in that: The end cover plate is further provided with a second through hole penetrating along the axial direction of the disc body, the second through hole comprises a first hole segment and a second hole segment connected in the axial direction of the disc body, the aperture of the first hole segment is larger than the aperture of the second hole segment, so as to form a step surface, the separation boss is penetrated in the second hole segment and extends to be located in the first hole segment, and the separation boss is welded to the step surface; The end cover assembly also includes a sealing sheet, which is arranged in the first hole section and abuts against the step surface to seal the injection hole on the partition boss, and a positioning groove is provided on the surface of the sealing sheet facing the step surface, and the partition boss is embedded in the positioning groove.

12. An energy storage device, characterized in that: The energy storage device includes a shell, a battery cell and an end cover assembly as described in claim 10 or 11, the shell has a accommodating cavity and an opening connected to the accommodating cavity, the battery cell is built into the accommodating cavity, the end cover plate is sealed at the opening, and the disk body of the collecting disk is welded to the battery cell.

13. An energy storage system, characterized in that: The energy storage system has the energy storage device according to claim 12.

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