Current collecting disc, end cover assembly, energy storage device, and energy storage system

Abstract

The present application discloses a current collecting disc, an end cover assembly, an energy storage device, and an energy storage system. The current collecting disc comprises a disc body portion and a partition boss. The disc body portion has a first surface and a second surface opposite to each other along the axial direction of the disc body portion, and is provided with a first through hole passing through the first surface and the second surface; and first grooves are formed on the first surface. The partition boss and the disc body portion are arranged as separate parts, and the partition boss protrudes from the first surface. The first through hole is at least partially covered by the partition boss, and the first through hole remains in communication with the first grooves; and the first grooves are at least partially exposed to the partition boss, so that the first grooves can remain in communication with an explosion-proof hole.

Description

Current collector plate, end cover assembly, energy storage device and energy storage system

[0001] Related Cross-Reference

[0002] The present application claims priority to the Chinese patent application No. 202421823799X, filed on July 30, 2024, entitled "Current collector plate, end cover assembly, energy storage device and energy storage system", the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to the technical field of energy storage, in particular to a current collector plate, an end cover assembly, an energy storage device and an energy storage system. BACKGROUND

[0004] When the energy storage device such as a battery fails, a large amount of gas will be generated. If the gas cannot be discharged in time, when it accumulates to a certain amount, the battery will explode, endangering personal and property safety. In order to prevent the battery from exploding due to high gas pressure and to protect the battery, a relief valve as a safety device is usually arranged in the end cover assembly of the battery. When the gas pressure inside the battery reaches a certain value, the relief valve can be blown open in time, thereby discharging the gas inside the battery in time.

[0005] However, due to the limitation of the internal space of the battery, the diffusion of the gas inside the battery is not conducive, which leads to the problem that the gas inside the battery cannot be discharged in time to the relief valve, so that the relief valve cannot be blown open in time. There is a hidden danger that the gas generated inside the battery cannot be discharged in time, which further leads to the problem that the gas pressure inside the battery exceeds the critical value and explodes, which is very dangerous. SUMMARY

[0006] The present application discloses a current collector plate, an end cover assembly, an energy storage device and an energy storage system, which can increase the exhaust area, facilitate the timely blowing open of the relief valve, reduce the risk of thermal runaway failure, and improve the safe use performance of the energy storage device.

[0007] In order to achieve the above-mentioned purpose, the first aspect of the present application discloses a current collector plate, which comprises a plate body part and a separation boss, the plate body part has a first surface and a second surface opposite along its axial direction, the plate body part is provided with a first through hole penetrating through the first surface and the second surface, the first surface is provided with a first groove, the separation boss is provided separately from the plate body part, and the separation boss is protruded on the first surface, wherein at least part of the first through hole is covered by the separation boss, and at least part of the first groove is exposed to the separation boss, so that the first groove can keep in communication with the relief hole.

[0008] In the current application, the current collector plate is provided with a first through hole and a first groove. The first through hole is kept through in the axial direction of the disc body part, and at least part of the first through hole is covered by the partition boss. The first through hole is in communication with the first groove to form an exhaust passage between the partition boss and the disc body part. At least part of the first groove is exposed to the partition boss and is not blocked by the partition boss. 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 to break the explosion-proof valve for pressure relief. The internal pressure of the energy storage device is reduced. Compared with the structure in which the disc body part and the partition boss are integrally formed and the partition boss is solid, the exhaust passage for discharging the gas generated by the battery cell to the explosion-proof valve is additionally provided, and the exhaust area is increased. Therefore, the gas generated by the battery cell can be discharged to the explosion-proof valve in time and quickly to ensure that the explosion-proof valve can discharge the gas in time for pressure relief and explosion prevention. The risk of explosion caused by thermal runaway failure is reduced, and the use safety of the energy storage device is improved.

[0009] The disc body part and the partition boss are separately provided, which is simpler than the structure of the current collector plate and the partition boss integrally formed. Therefore, the separately provided disc body part and partition boss can reduce the molding difficulty of the product, improve the product yield, and reduce the cost.

[0010] The second aspect of the present application discloses an end cover assembly, which comprises an end cover plate, an explosion-proof valve, and a current collector plate as described in the first aspect. The end cover plate is provided with an explosion-proof hole penetrating in the axial direction of the disc body part. The explosion-proof valve is arranged in the explosion-proof hole. The partition boss of the current collector plate abuts against the end cover plate to space the end cover plate and the disc body part apart to define a pressure relief passage in communication with the first groove between the end cover plate and the disc body part. The pressure relief passage is in communication with the explosion-proof hole. The end cover assembly with the current collector plate as described in the first aspect can also increase the exhaust area, facilitate the timely explosion of the explosion-proof valve, reduce the risk of thermal runaway failure, and improve the safe use performance of the energy storage device.

[0011] The third aspect of the present application discloses an energy storage device, which comprises a shell, a battery cell, and an end cover assembly as described in the second aspect. The shell has a receiving cavity and an opening in communication with the receiving cavity. The battery cell is built in the receiving cavity. The end cover plate is sealingly arranged at the opening. The disc body part of the current collector plate is welded to the battery cell. The energy storage device with the end cover assembly as described in the second aspect has the same or similar beneficial effects as the current collector plate as described in the first aspect. Therefore, the energy storage device with the end cover assembly as described in the second aspect can also increase the exhaust area, facilitate the timely explosion of the explosion-proof valve, reduce the risk of thermal runaway failure, and improve the safe use performance of the energy storage device.

[0012] The fourth aspect of the present application discloses an energy storage system, which has the energy storage device as described in the third aspect above. The energy storage system having the energy storage device as described in the third aspect above can increase the exhaust area, facilitate the timely explosion of the explosion-proof valve, reduce the risk of thermal runaway failure, and improve the safety performance of the energy storage device, because the energy storage device has the same or similar beneficial effects as the current collector plate described in the first aspect. BRIEF DESCRIPTION OF DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0014] Fig. 1 is a first structural schematic diagram of an energy storage system disclosed by the embodiments of the present application;

[0015] Fig. 2 is a second structural schematic diagram of an energy storage system disclosed by the embodiments of the present application;

[0016] Fig. 3 is an exploded structural schematic diagram of an energy storage device disclosed by the embodiments of the present application;

[0017] Fig. 4 is an exploded structural schematic diagram of an end cover assembly disclosed by the embodiments of the present application;

[0018] Fig. 5 is a front structural schematic diagram of an end cover assembly disclosed by the embodiments of the present application;

[0019] Fig. 6 is a sectional view of the end cover assembly in Fig. 5 along the direction of A-A;

[0020] Fig. 7 is an exploded schematic diagram of Fig. 6;

[0021] Fig. 8 is a partial enlarged view of M in Fig. 7;

[0022] Fig. 9 is an exploded structural schematic diagram of a current collector plate disclosed by the embodiments of the present application;

[0023] Fig. 10 is a front structural schematic diagram of a current collector plate disclosed by the embodiments of the present application;

[0024] Fig. 11 is a sectional view of the current collector plate in Fig. 10 along the direction of B-B.

[0025] Main reference signs 1000- energy storage system; 100- energy storage device; 1- shell; 11- accommodating cavity; 12- opening; 2- battery cell; 3- end cover assembly; 31- end cover plate; 311- anti-explosion hole; 312- second through hole; 3121- first hole section; 3122- second hole section; 3123- step surface; 32- anti-explosion valve; 33- current collector plate; 331- plate body; 331a- first surface; 331b- second surface; 3311- first through hole; 3312- first groove; 3313- exhaust hole; 3314- reinforcing convex rib; 3315- limiting groove; 332- separation 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- convex part; 34- pressure relief channel; 35- sealing glue nail; 351- head; 352- main body; 36- sealing sheet; 361- positioning groove; 200- electric energy conversion device; 300- first user load; 400- second user load; 210- high-voltage cable; 310- first electric energy conversion device; 410- second electric energy conversion device. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0027] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0028] In addition, in addition to indicating the orientation or positional relationship, the above-mentioned part of the terms may also be used to indicate other meanings, for example, the term "upper" may also be used to indicate a certain dependent relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meaning of these terms in the present application can be understood according to the specific situation.

[0029] In addition, the terms "mounting", "arrangement", "provided with", "connected", "linked" should be understood broadly. For example, it can be fixed connection, detachable connection, or integral structure; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication between two devices, elements or components. The specific meaning of the above terms in the present application can be understood according to the specific circumstances by those skilled in the art.

[0030] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not intended to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise stated, the meaning of "multiple" is two or more.

[0031] Since the energy required by people has strong time and space, in order to reasonably use energy and improve the utilization rate of energy, it is necessary to store one form of energy in the same form or convert it into another form of energy through a medium or device, and release it in a specific energy form based on future application needs. It is well known that the main way to generate green electricity at present is to develop green energy such as photovoltaic and wind power to replace fossil energy.

[0032] At present, the generation of green electricity generally depends on photovoltaic, wind power, water potential, etc., while wind energy and solar energy generally have strong intermittency and large fluctuation, which can cause unstable power grid, insufficient electricity at peak load, too much electricity at low load, and unstable voltage can also cause damage to electricity. Therefore, due to insufficient electricity demand or insufficient grid acceptance capacity, the problem of "abandoning wind and light" may occur. To solve these problems, it is necessary to rely on energy storage, that is, to store electricity in other forms of energy through physical or chemical means, and release the electricity when needed. In short, energy storage is similar to a large "power bank", which stores electricity when photovoltaic and wind energy is sufficient, and releases the stored electricity when needed.

[0033] Taking electrochemical energy storage as an example, the embodiment of the present application provides an energy storage device, which is provided with a group of energy storage batteries inside, mainly using chemical elements in the battery as energy storage medium. The charging and discharging process is accompanied by chemical reaction or change of the energy storage medium. Simply put, the electricity generated by wind and solar energy is stored in a chemical battery, and the stored electricity is released for use when the use of external electricity reaches the peak, or transferred to places where electricity is in short supply for use.

[0034] The current energy storage (i.e. energy storage) application scenarios are relatively wide, including power generation side energy storage, power grid side energy storage, renewable energy grid-connected energy storage, and user side energy storage, etc. The corresponding types of energy storage devices include:

[0035] ① Large energy storage container applied in grid side energy storage scenario, which can be used as high-quality active and reactive power regulation power supply in the power grid, realizes load matching of electric energy in time and space, enhances renewable energy consumption capacity, and is of great significance in terms of power grid system backup, relieving peak load power supply pressure and peak regulation;

[0036] ② Small and medium-sized energy storage cabinets applied in industrial and commercial energy storage scenarios (banks, shopping malls, etc.) on the user side and small household energy storage boxes applied in household energy storage scenarios on the user side, the main operation mode of which is "peak clipping and valley filling". Because there is a large price difference in electricity bills at peak and valley positions according to electricity demand, users usually charge the energy storage cabinet / box during the low electricity price period in order to reduce costs; during the high electricity price period, the electricity in the energy storage device is discharged for use, so as to achieve the purpose of saving electricity bills. In addition, in remote areas and areas with high incidence of natural disasters such as earthquakes and hurricanes, the existence of household energy storage devices is equivalent to the user providing a backup power supply for himself and the power grid, which eliminates the inconvenience caused by frequent power outages due to disasters or other reasons.

[0037] Please refer to FIG. 1, which is a structural schematic diagram of the energy storage system provided by an embodiment of the present application as a household energy storage system, and the embodiment of the present application takes the household energy storage scenario in user side energy storage as an example for illustration, and the energy storage device provided by the embodiment of the present application is not limited to the household energy storage scenario.

[0038] As shown in FIG. 1, the energy storage system 1000 provided by the embodiment of the present application includes an energy storage device 100 and an electric energy conversion device 200 (a photovoltaic panel), a first user load 300 (a street lamp), and a second user load 400 (for example, a household appliance such as an air conditioner, etc.), the energy storage device 100 is a small energy storage box, which can be installed on an outdoor wall in a wall-mounted manner. Specifically, the photovoltaic panel can convert solar energy into electric energy during the low electricity price period, the energy storage device 100 is used to store the electric energy and supply the street lamp and the household appliance for use during the high electricity price period, or supply power during power grid outage / power failure.

[0039] Please refer to FIG. 2, which is a structural schematic diagram of the energy storage system provided by another embodiment of the present application, and the embodiment of the present application takes the generation / distribution side shared energy storage scenario as an example for illustration, and the energy storage device 100 provided by the present application is not limited to the generation / distribution side energy storage scenario thereof.

[0040] As shown in FIG. 2, the energy storage system 1000 provided by the embodiment of the present application comprises 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, and are connected with the high-voltage cable 210 and supplied to the power distribution network for use. When the power load is low, the first electric energy conversion device 310 and the second electric energy conversion device 410 generate excess power, which is stored in the energy storage device 100, thereby reducing the rate of abandoned wind and light and improving the problem of new energy power generation consumption. When the power load is high, the grid issues an instruction to transmit the electric energy stored in the energy storage device 100 in combination with the high-voltage cable 210 in the grid-connected mode to supply the power consumption side, thereby providing peak shaving, frequency modulation, backup, and other services for grid operation, fully playing the role of grid peak shaving, promoting the peak shaving and valley filling of the grid, and relieving the power supply pressure of the grid.

[0041] 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, heat energy, tidal energy, biomass energy, and mechanical energy into electric energy.

[0042] In the present application, the number of energy storage devices 100 can be multiple, and the multiple energy storage devices 100 are connected in series or in parallel with each other, and are supported and electrically connected by an isolation plate (not shown in the figure). In the embodiment, "multiple" means two or more. The energy storage device 100 can also be provided with an energy storage box outside for accommodating the energy storage device 100.

[0043] Optionally, the energy storage device 100 can include but is not limited to a single battery, a battery module, a battery pack, a battery system, etc. The actual application form of the energy storage device 100 provided by the embodiment of the present application can be but is not limited to the listed products, and can 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 description. When the energy storage device 100 is a single battery, the energy storage device 100 can be at least one of a cylindrical battery, a square battery, etc.

[0044] The technical solutions of the present application are further described in detail below by taking the energy storage device 100 as a single battery as an example.

[0045] Referring to FIG. 3, the energy storage device 100 provided by the embodiment of the present application comprises a shell 1, an electric core 2 and an end cover assembly 3. The shell has a receiving cavity 11 and an opening 12 communicating with the receiving cavity 11, the electric core 2 is built in the receiving cavity 11, and the end cover assembly 3 is sealed at the opening 12 of the shell to seal the electric core 2 in the receiving cavity 11 of the shell. The electric core 2 can be one or more. When the electric core 2 is multiple, the multiple electric cores 2 can be arranged along the length direction of the energy storage device 100, or can be arranged along the width direction of the energy storage device 100, or can be arranged in an array along the length direction and the width direction of the energy storage device 100. In addition, the multiple electric cores 2 can be connected in series or in parallel, or some of the electric cores 2 are connected in series and the other electric cores 2 are connected in parallel.

[0046] Referring to FIGS. 3 and 4, the end cover assembly 3 provided by the embodiment of the present application comprises an end cover plate 31, an explosion-proof valve 32 and a current collecting disc 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 is opened in time by sensing the change of the internal air pressure of the shell, and the exhaust pressure relief is performed 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 disc 33 is electrically connected between the end cover plate 31 and the electric core 2 to output the current in the electric core 2 to the energy storage device 100. The axial direction of the end cover plate 31 is parallel to the height direction of the energy storage device 100, for example, the up-down direction in FIG. 3.

[0047] Referring to FIGS. 5 to 7, the current collecting disc 33 provided by the embodiment of the present application comprises a disc body part 331 and a separation boss 332. The disc body part 331 has a first surface 331a and a second surface 331b opposite to each other along the axial direction thereof. The separation boss 332 is protruded on the first surface 331a, and the separation boss 332 abuts against the end cover plate 31 to separate the end cover plate 31 from the disc body part 331, so as to define a pressure relief channel 34 communicating with the explosion-proof hole 311 between the end cover plate 31 and the disc body part 331. The axial direction of the disc body part 331 is parallel to the axial direction of the end cover plate 31.

[0048] It should be known that the energy storage device 100 may be caused to thermal runaway due to various reasons during use, and the thermal runaway reaction may be different in intensity when the energy storage device 100 is in thermal runaway. 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 rise. However, due to the limited internal space of the battery, the gas cannot be discharged in time, causing the internal pressure of the battery to continuously accumulate, which may pose an explosion risk. In addition, the thermal runaway reaction of the energy storage device 100 may be relatively severe, and a large amount of gas may 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.

[0049] When the energy storage device 100 is in 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 the pressure relief channel 34 has a certain space, 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 internal pressure of the energy storage device 100 remains at a low level, thereby avoiding the risk of high internal pressure of the energy storage device 100. When the thermal runaway reaction is relatively severe, a large amount of gas is generated inside the battery cell 2 in a short period of time. When the gas enters the pressure relief channel 34, the internal pressure of 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.

[0050] Please refer to FIGS. 6-9, the partitioning boss 332 in the present application is provided separately from the disc body 331, and the disc 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 recess 3312.

[0051] The first through hole 3311 is at least partially covered by the separation boss 332, that is, the entire first through hole 3311 can be covered by the separation boss 332, or a part of the first through hole 3311 is covered by the separation boss 332 and the other part is exposed to the separation boss 332. The first groove 3312 is at least partially exposed to the separation boss 332, that is, the entire first groove 3312 can be exposed to the separation boss 332 and not covered by the separation boss 332, or a part of the first groove 3312 is covered by the separation boss 332 and the other part is exposed to the separation boss 332, so that the first groove 3312 can be in communication with the explosion-proof hole 311, so that when the battery cell 2 is in 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 and be discharged to the explosion-proof valve 32, so as to break the explosion-proof valve 32 to relieve pressure, thereby reducing the internal pressure of the energy storage device 100. Compared with the structure that the disc body part 331 and the separation boss 332 are integrally formed and the separation boss 332 is solid, it is equivalent to additionally increasing the 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 additionally increasing the exhaust channel that can discharge the gas generated by the battery cell 2 to the explosion-proof valve 32, thereby increasing the exhaust area, so that the gas generated by the battery cell 2 can be discharged to the explosion-proof valve 32 in time and quickly, so as to ensure that the explosion-proof valve 32 can discharge gas in time to relieve pressure and explosion, thereby reducing the risk of thermal runaway failure and explosion, and improving the use safety of the energy storage device 100.

[0052] Since the disc body part 331 and the separation boss 332 are separately arranged, both of them are simpler in structure than the structure of the current collector disc 33 and the separation boss 332 integrally formed, so that the disc body part 331 and the separation boss 332 can reduce the molding difficulty of the product, improve the product yield, and reduce the cost.

[0053] In some optional embodiments, a portion of the first groove 3312 is covered by the partitioning boss 332, and another portion of the first groove 3312 is exposed from the partitioning boss 332 and is not covered by the partitioning boss 332, so that the first groove 3312 can be kept in communication with the explosion-proof hole 311; the partitioning boss 332 is provided with a second groove 3321 on the surface thereof facing the disc body 331, the through hole portion of the first through hole 3311 covered by the partitioning boss 332, and the groove portion of the first groove 3312 covered by the partitioning boss 332 are kept in communication through the second groove 3321, so that when the battery cell 2 is in thermal runaway, the gas generated by the battery cell 2 can enter the pressure relief passage 34 and be discharged to the explosion-proof valve 32 through the first through hole 3311, the second groove 3321 and the first groove 3312 in sequence to break the explosion-proof valve 32 to relieve pressure, thereby reducing the risk of explosion due to thermal runaway failure and improving the use safety of the energy storage device 100.

[0054] In some optional embodiments, the partitioning 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 in communication with the first through hole 3311. When the partitioning boss 332 is provided with the second groove 3321 on the surface thereof facing the disc body 331, the liquid injection hole 3322 is in communication with the second groove 3321 to be in communication with the first through hole 3311, that is, the liquid injection hole 3322 can be in communication 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 diameter of the liquid injection hole 3322 is smaller than the diameter of the first through hole 3311. During liquid injection, electrolyte can be injected into the energy storage device 100 through the liquid injection hole 3322 and the first through hole 3311, so that the battery cell 2 can be soaked in the electrolyte to ensure the performance of the battery cell 2, thereby avoiding the need to additionally open a through hole in the end cover plate 31 to avoid affecting the structural strength of the end cover plate 31. Meanwhile, the liquid injection hole 3322 is coaxially arranged with the first through hole 3311, and the diameter of the liquid injection hole 3322 is smaller than the diameter of the first through hole 3311, so that most of the electrolyte injected through the liquid injection hole 3322 can enter the energy storage device 100 through the first through hole 3311 to soak the battery cell 2.

[0055] After the liquid injection is completed, the liquid injection hole 3322 is used for penetrating the sealing glue pin 35, so that the liquid injection hole 3322 can be sealed by the sealing glue pin 35 to ensure that the battery cell 2 can be placed in a sealed cavity after the liquid injection is completed.

[0056] Optionally, in combination with FIGS. 6-8, the liquid injection hole 3322 can include a first liquid injection hole section 3322a and a second liquid injection hole section 3322b that are in communication in the axial direction of the disc body 331, the first liquid injection hole section 3322a has a larger hole diameter than the second liquid injection hole section 3322b to form a stepped surface 3322c, the sealing glue nail 35 includes a head 351 and a body 352 that are 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 body 352, the body 352 is arranged in the second liquid injection hole section 3322b, and the head 351 is arranged in the first liquid injection hole section 3322a and abuts against the stepped surface 3322c to avoid the sealing glue nail 35 from being detached from the liquid injection hole 3322 in the direction towards the battery cell 2, while also avoiding the sealing glue nail 35 from protruding out of the liquid injection hole 3322, thereby avoiding the situation that the sealing glue nail 35 is loosened due to accidental contact with the sealing glue nail 35, to ensure the sealing effect of the sealing glue nail 35 on the liquid injection hole 3322.

[0057] To further improve the sealing of the sealing glue nail 35 in the liquid injection hole 3322, the end cover assembly 3 further includes a sealing sheet 36, which is arranged on the side of the end cover plate 31 away from the current collecting disc 33 and covers the sealing glue nail 35, so that the sealing sheet 36 can further seal the liquid injection hole 3322.

[0058] Optionally, the sealing nail can be welded on the end cover plate 31 by welding to realize the sealing connection between the sealing sheet 36 and the end cover plate 31.

[0059] In some optional embodiments, the second groove 3321 is provided with a protrusion 3323 towards the groove bottom surface of the disc body 331, and the liquid injection hole 3322 penetrates the protrusion 3323 in the axial direction of the disc body 331, so that the protrusion 3323 can extend the depth of the liquid injection hole 3322 in the axial direction of the disc body 331, thereby increasing the contact area between the liquid injection hole 3322 and the sealing glue nail 35, and further improving the stability of the sealing glue nail 35 in the liquid injection hole 3322.

[0060] In some optional embodiments, as shown in FIG. 9, the first through hole 3311 and the disc body 331 are coaxially arranged, and the first groove 3312 is a plurality of grooves, each of which extends in the radial direction of the disc body 331, so that the disc body 331 can maintain its structural symmetry to ensure the structural stability of the disc body 331, while further increasing the exhaust passage and further increasing the exhaust area, so that the gas generated by the battery cell can be quickly discharged to the explosion-proof valve, to ensure that the explosion-proof valve can timely discharge the gas for pressure relief and explosion prevention, thereby greatly reducing the risk of explosion due to thermal runaway failure, and further improving the use safety of the energy storage device.

[0061] Further, since the first through hole 3311 and the disc body part 331 are coaxially arranged, and the injection hole 3322 is coaxially arranged with the first through hole 3311 as known from the foregoing, the injection hole 3322 is located at the center of the disc body part 331. When injecting electrolyte, the electrolyte is injected from the center, which can make the energy storage device have higher injection efficiency. The electrolyte flows from the center of the battery cell, which can improve the wettability of the battery cell.

[0062] In some optional embodiments, as shown in FIGS. 6-8, the end cover plate 31 is further provided with a second through hole 312 penetrating along the axial direction of the disc body part 331. The first end 332a1 of the partitioning boss 332 away from the disc body part 331 is embedded in the second through hole 312, and the first end 332a1 of the partitioning boss 332 away from the disc body part 331 is welded to the surface of the end cover plate 31 away from the disc body part 331. That is, when welding, the first end 332a1 of the partitioning boss 332 away from the disc body part 331 is inserted into the second through hole 312, so that the first end 332a1 of the partitioning boss 332 away from the disc body part 331 can be welded to the surface of the end cover plate 31 away from the disc body part 331, thereby realizing the electrical connection between the current collecting disc 33 and the end cover plate 31. In this way, the current collecting disc 33 in the present application does not need to be bent, and compared with the bent current collecting disc 33, the problem of easy fracture of the bent current collecting disc 33 due to vibration for many times can be solved, thereby being beneficial to improving the service life of the current collecting disc 33. At the same time, since the first end 332a1 of the partitioning boss 332 away from the disc body part 331 can be inserted into the through hole, the first end 332a1 of the partitioning boss 332 away from the disc body part 331 can be welded to the surface of the end cover plate 31 away from the disc body part 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.

[0063] In addition, the first end 332a1 of the current collecting disc 33 is inserted into the end cover plate 31, which can increase the contact area between the current collecting disc 33 and the end cover plate 31 while positioning the end cover plate 31. The greater the contact area, the lower the resistance, thereby reducing the internal resistance of the energy storage device and making the charge and discharge performance of the energy storage device better.

[0064] Further, 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 disc body part 331, the hole diameter of the first hole section 3121 is larger than the hole diameter of the second hole section 3122 to form a stepped surface 3123; the first end 332a1 of the partitioning boss 332 away from the disc body part 331 is embedded in the second hole section 3122 and extends to be located in the first hole section 3121, the first end 332a1 is welded with the stepped surface 3123; the sealing sheet 36 is arranged in the first hole section 3121 and abuts against the stepped surface 3123 to seal the liquid injection hole 3322 on the partitioning boss 332, and the surface of the sealing sheet 36 towards the stepped 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, the sealing sheet 36 is arranged in the first hole section 3121 to form positioning of the sealing sheet 36, and at the same time, the first end 332a1 of the partitioning boss 332 extends into the sealing sheet 36, so that the sealing sheet 36 can be double-positioned to facilitate the installation of the sealing sheet 36, and at the same time, one of the positioning effects of the sealing sheet 36 is realized by the cooperation of the first end 332a1 of the partitioning boss 332 and the positioning groove 361, and it is not necessary to additionally arrange a positioning column to cooperate with the positioning groove 361, so that the structure of the end cover assembly 3 can be simplified to facilitate the processing and forming of the end cover assembly 3.

[0065] Exemplarily, the partitioning boss 332 includes a first boss 332a and a second boss 332b which are connected in the axial direction of the disc body part 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 with the disc body part 331, and the second boss 332b also abuts against the end cover plate 31 to space the end cover plate 31 and the disc body part 331 apart, so as to define a pressure relief channel 34 which communicates with the explosion-proof hole 311 between the end cover plate 31 and the disc body part 331.

[0066] In some optional embodiments, as shown in FIG. 9, the first groove 3312 is arranged along the radial direction of the disc body 331, and the depth of the first groove 3312 in the axial direction of the disc body 331 can be 0.2 mm-0.4 mm, that is, the distance between the surface of the disc body 331 and the bottom surface of the first groove 3312 in the axial direction of the disc body 331 is 0.2 mm-0.4 mm, for example, 0.2 mm, 0.22 mm, 0.25 mm, 0.28 mm, 0.3 mm, 0.33 mm, 0.35 mm, 0.37 mm, 0.39 mm, or 0.4 mm, etc., and the length of the first groove 3312 in the circumferential direction of the disc body 331 can be 6 mm-10 mm, for example, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, or 10 mm, etc. When the first groove 3312 satisfies the above size relationship, a larger exhaust passage can be formed between the partitioning boss 332 and the disc body 331, the flow rate of the gas is increased, so that the gas can be quickly discharged when the battery cell 2 is out of control, and the gas pressure relief is timely, so as to prevent the internal gas pressure of the energy storage device from being too high, thereby improving the safety and reliability of the energy storage device.

[0067] In some optional embodiments, as shown in FIGS. 9-11, the disc body 331 is further provided with an exhaust hole 3313 penetrating through the first surface 331a and the second surface 331b. By arranging the exhaust hole 3313, the flow channel of the gas flowing to the explosion-proof valve can be further increased, thereby more facilitating the rapid discharge of the gas when the battery cell is out of control, timely gas pressure relief, preventing the internal gas pressure of the energy storage device from being too high, and thereby improving the safety and reliability of the energy storage device.

[0068] Optionally, the exhaust hole 3313 is a plurality of exhaust holes 3313, which can be distributed at intervals along the circumferential direction of the disc body 331, each exhaust hole 3313 is located between two adjacent first grooves 3312, and each exhaust hole 3313 is a completely hollow heat dissipation hole structure, rather than an exhaust structure with a plurality of intersecting ribs arranged inside to divide the inside 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 has a larger exhaust area, thereby increasing the area of the gas pressure relief passage, more quickly discharging the gas to the explosion-proof valve, timely gas pressure relief, and thereby further improving the safety and reliability of the energy storage device.

[0069] In some optional embodiments, the first surface 331a of the disc body part 331 is convexly provided with a reinforcing rib 3314, a limiting groove 3315 is formed between the reinforcing rib 3314 and the first surface 331a, and the separation boss 332 is arranged in the limiting groove 3315, so that the structural strength of the disc body part 331 can be improved by the reinforcing rib, the disc body part 331 is not easy to deform, and the separation boss 332 can be limited and positioned by the limiting groove 3315, so as to facilitate the installation of the separation boss 332.

[0070] The technical features of the above embodiments can be combined in any manner. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present application.

[0071] In addition, the above-described embodiments only express several implementation manners of the present application, the description is more specific and detailed, but it should not be understood as the limitation of the patent scope of the present application. It should be pointed out that, for those skilled in the art, several modifications 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 the present application should not be understood as the limitation, the protection scope of the present application should be subject to the appended claims.

Claims

1. A collector disk, characterized in that, Applied to an end cap assembly, the end cap assembly having an explosion-proof hole for installing an explosion-proof valve, the manifold includes: The disk body portion has a first surface and a second surface opposite each other along its axial direction, and the disk body portion is provided with a first through hole penetrating the first surface and the second surface, and the first surface is provided with a first groove; and A dividing boss is integrally disposed with the disk body and protrudes from the first surface; Wherein, at least a portion of the first through hole is covered by the partition boss, and the first through hole is in communication with the first groove, and at least a portion of the first groove is exposed outside the partition boss, so that the first groove can be in communication with the explosion-proof hole.

2. The collector disk 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 outside the partition boss, so that the first groove can maintain communication with the explosion-proof hole; The surface of the dividing boss facing the disc body is provided with a second groove. The through hole portion covered by the dividing boss and the groove portion of the first groove covered by the dividing boss are kept in communication through the second groove.

3. The collector disk according to claim 2, characterized in that, The dividing boss is provided with a liquid injection hole that extends through the axial direction of the disc body. The liquid injection hole communicates with the second groove and with the first through hole. The liquid injection hole and the first through hole are coaxially arranged, and the diameter of the liquid injection hole is smaller than the diameter of the first through hole.

4. The collector disk according to claim 3, characterized in that, The second groove has a protrusion on the bottom surface of the groove facing the disc body. The liquid injection hole passes through the protrusion along the axial direction of the disc body and is used for the insertion of sealing nails.

5. The collector disk according to claim 1, characterized in that, The partition boss is provided with a liquid injection hole that extends through the axial direction of the disc body. The liquid injection hole communicates with the first through hole and is coaxially arranged with the first through hole. The diameter of the liquid injection hole is smaller than the diameter of the first through hole.

6. The collector disk according to any one of claims 1-5, characterized in that, The first groove extends radially along the disk body portion, and the depth of the first groove in the axial direction of the disk body portion is 0.2mm-0.4mm, and the length of the first groove in the circumferential direction of the disk body portion is 6mm-10mm.

7. The collector disk according to any one of claims 1-5, characterized in that, The first through hole and the disk body are coaxially arranged, and there are multiple first grooves, each of which extends radially along the disk body.

8. The collector disk according to any one of claims 1-5, characterized in that, The disc body is also provided with an exhaust hole that penetrates the first surface and the second surface.

9. The collector disk according to any one of claims 1-5, 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 disposed in the limiting groove.

10. An end cap assembly, characterized in that, The end cap assembly includes an end cap plate, an explosion-proof valve, and a manifold as described in any one of claims 1-9. The end cap plate has an explosion-proof hole that extends axially through the disc body portion. The explosion-proof valve is disposed in the explosion-proof hole. The partition boss of the manifold abuts against the end cap plate, thereby separating the end cap plate from the disc body portion to define a pressure relief channel between the end cap plate and the disc body portion. The pressure relief channel communicates with the first groove and the explosion-proof hole, respectively.

11. The end cap assembly according to claim 10, characterized in that, The end cover plate is also provided with a second through hole that extends through the axial direction of the disk body. The second through hole includes a first hole section and a second hole section that are connected in the axial direction of the disk body. The diameter of the first hole section is larger than the diameter of the second hole section to form a stepped surface. The partition boss is inserted in the second hole section and extends to be located in the first hole section. The partition boss is welded to the stepped surface. The end cap assembly further includes a sealing sheet, which is disposed in the first hole segment and abuts against the stepped surface to seal the injection hole on the partition boss. The surface of the sealing sheet facing the stepped surface is provided with a positioning groove, and the partition boss is embedded in the positioning groove.

12. An energy storage device, characterized in that, The energy storage device includes a housing, a battery cell, and an end cap assembly as described in claim 10 or 11. The housing has a receiving cavity and an opening communicating with the receiving cavity. The battery cell is built into the receiving cavity. The end cap is sealed at the opening. The disk body portion of the current collector is welded to the battery cell.

13. An energy storage system, characterized in that, The energy storage system has the energy storage device as described in claim 12.

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