Lower plastic, end cover assembly, energy storage apparatus and electric device

Abstract

Disclosed in the present application are a lower plastic, an end cover assembly, an energy storage apparatus and an electric device. The lower plastic has a first surface and a second surface, which are disposed facing away from each other in the thickness direction of the lower plastic; the lower plastic is provided with a groove, a flow guide hole, a recess, a plurality of first ejector pin portions, a plurality of second ejector pin portions, and a plurality of third ejector pin portions, wherein the groove and the recess are located at two opposite ends of the lower plastic in the length direction, an opening of the groove is located in the first surface, and the flow guide hole penetrates the bottom wall of the groove; and the diameter of the flow guide hole is gradually reduced in the direction from the first surface to the second surface, the opening of the recess is located in the first surface, and the plurality of first ejector pin portions, the plurality of second ejector pin portions and the plurality of third ejector pin portions are symmetrical with respect to a center line of the lower plastic in the width direction. The present application can ensure the structural strength of the lower plastic, and can improve the production yield of the lower plastic.

Description

Lower plastic, end cover assembly, energy storage device and electrical equipment

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on September 13, 2023, with application number 2023111766121 and application name “Lower plastic, end cover assembly, energy storage device and electrical equipment”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of energy storage technology, and in particular to a lower plastic, an end cover assembly, an energy storage device, and electrical equipment. Background Art

[0003] A secondary battery (rechargeable battery), also known as a rechargeable battery or storage battery, is a battery that can be recharged to activate the active material and continue to be used after the battery is discharged. The recyclable nature of secondary batteries has made them gradually become the main power source for electrical equipment. As the demand for secondary batteries gradually increases, people's performance requirements in various aspects are also getting higher and higher, especially the requirements for the energy density per unit volume of the battery. The thickness of the battery's end cap assembly is an important parameter affecting the battery's energy density per unit volume. The current end cap assembly includes a lower plastic for insulation between the top cover and the pole. In order to increase the energy density per unit volume of the battery, the lower plastic is usually designed to be very thin. However, the lower plastic is often formed by injection molding. When the lower plastic is demolded, it is easy to cause deformation such as bending and twisting of the lower plastic, resulting in low yield.

[0004] Summary of the Invention

[0005] The present application provides a lower plastic, an end cover assembly, an energy storage device and an electrical equipment, which can ensure the structural strength of the lower plastic and improve the production yield of the lower plastic.

[0006] In a first aspect, the present application provides a lower plastic, the lower plastic having a first surface and a second surface, the first surface and the second surface being arranged in opposite directions along a thickness direction of the lower plastic;

[0007] The lower plastic is provided with a groove, a guide hole, a recess, a plurality of first ejector pins, a plurality of second ejector pins, and a plurality of third ejector pins. The groove is located at one end of the lower plastic in the longitudinal direction, the bottom wall of the groove protrudes from the second surface, and the opening of the groove is located on the first surface. The guide hole passes through the bottom wall of the groove, and the aperture of the guide hole gradually decreases from the first surface to the second surface. The recess is located at the other end of the lower plastic in the longitudinal direction, the bottom wall of the recess protrudes from the second surface, and the opening of the recess is located on the first surface.

[0008] The plurality of first ejector pins are all provided on the first surface and are located between the groove and the concave portion and are spaced apart from each other. The plurality of second ejector pins are all provided on the groove bottom wall of the concave portion and are spaced apart from each other. The plurality of third ejector pins are all provided on the groove bottom wall of the groove and are spaced apart from each other. The plurality of first ejector pins, the plurality of second ejector pins and the plurality of third ejector pins are all symmetrical with respect to the center line of the lower plastic in the width direction.

[0009] In a second aspect, the present application provides an end cover assembly, comprising an end cover, an explosion-proof valve, and the lower plastic as described above. Along the thickness direction of the end cover assembly, the lower plastic is stacked on one side of the end cover, and the first surface of the lower plastic faces the end cover. Along the thickness direction of the end cover assembly, the explosion-proof valve is opposite to the bottom wall of the recess.

[0010] In a third aspect, the present application provides an energy storage device, comprising a shell, an electrode assembly and an end cover assembly as described above, wherein the shell has an opening, the shell is provided with a receiving cavity, the electrode assembly is received in the receiving cavity, and the end cover assembly is mounted on the shell and covers the opening.

[0011] In a fourth aspect, the present application provides an electrical device comprising the energy storage device as described above, wherein the energy storage device is used to store electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the implementation. Obviously, the drawings described below are only some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained like these drawings without paying any creative work.

[0013] FIG1 is a diagram illustrating an application scenario of an energy storage device provided in an embodiment of the present application;

[0014] FIG2 is a schematic structural diagram of the energy storage device shown in FIG1 ;

[0015] FIG3 is an exploded schematic diagram of the end cap assembly of the energy storage device shown in FIG2 ;

[0016] FIG4 is a schematic structural diagram of the first lower plastic shown in FIG3 ;

[0017] FIG5 is a schematic diagram of the structure of the first lower plastic member shown in FIG4 at a second angle;

[0018] FIG6 is a schematic diagram of the cross-sectional structure of the air vent shown in FIG4 ;

[0019] FIG7 a is a schematic diagram of the structure of the first lower plastic shown in FIG4 at a third angle, wherein the second and third groups of second ejector pins are omitted;

[0020] FIG7 b is a schematic diagram of the structure of the first lower plastic shown in FIG4 at a third angle, wherein the first and third groups of second ejector pins are omitted;

[0021] FIG7 c is a schematic diagram of the structure of the first lower plastic shown in FIG4 at a third angle, wherein the first and second groups of second ejector pins are omitted;

[0022] FIG8 is a partial cross-sectional structural diagram of the first lower plastic shown in FIG4 .

[0023] Explanation of the accompanying symbols: 5000 - energy storage system, 4100 - first electric energy conversion device, 4200 - second electric energy conversion device, 3000 - first electric device, 2000 - second electric device, 1000 - energy storage device, 200 - electrode assembly, 100 - end cover assembly, 30 - lower plastic, 40 - end cover, 70 - explosion-proof valve, 50 - upper plastic assembly, 60 - electrode pole, 61 - first pole, 62 - second pole, 51 - first upper plastic, 52 - second upper plastic, 41 - end cover body, 411 - first through hole, 412 - second through hole, 413 - injection hole, 414 -welding groove, 10-first lower plastic, 20-second lower plastic, 11-body, 14-boss, 15-protrusion, 111-body surface, 112-second surface, 12-holding protrusion, 113-pole through hole, 141-fourth surface, 142-boss surface, 13-recess, 131-first groove bottom wall, 132-first side wall, 133-second side wall, 1311-first sub-bottom wall, 1312-second sub-bottom wall, 1411-first sub-surface, 1412-second sub-surface, 1316-through groove, 1316a-first wall, 1316b-second wall, 1313-first rib, 1314-second rib, 1315-ventilation hole, 151-third surface, 152-raised surface, 101-first surface, 102-lower plastic surface, 153-stopper, 154-side stopper, 16-groove, 161-second groove bottom wall, 162-first A groove side wall, 163-a second groove side wall, 164-reinforcement rib, 165-guide groove, 166-guide hole, 17-first injection molding part, 171-first opening end, 172-first injection molding protrusion, 18-second injection molding part, 181-second opening end, 182-second injection molding protrusion, 191-first anti-overflow groove, 192-second anti-overflow groove, S1-first ejector part, S2-second ejector part, S3-third ejector part. DETAILED DESCRIPTION

[0024] Because the energy people need is highly temporal and spatially dependent, rationally utilizing energy and improving its efficiency requires a medium or device that can store one form of energy in the same form or convert it into another, allowing it to be released in a specific form based on future application needs. As we all know, to achieve the goal of carbon neutrality, the primary method for generating green electricity is to develop green energy sources such as photovoltaics and wind power to replace fossil fuels. Currently, green electricity generation generally relies on photovoltaics, wind power, and hydropower. However, wind and solar power are generally intermittent and volatile, leading to grid instability, insufficient power during peak hours, and excessive power during off-peak hours. Unstable voltage can also damage electricity. Therefore, insufficient electricity demand or insufficient grid capacity can lead to "wind and solar curtailment." Addressing these issues requires energy storage. That is, electrical energy is converted into other forms of energy through physical or chemical means and stored, and then the energy is converted into electrical energy and released when needed. Simply put, energy storage is like a large "power bank". When there is sufficient photovoltaic and wind energy, electrical energy is stored and the stored electricity is released when needed.

[0025] Taking electrochemical energy storage as an example, this solution provides an energy storage device 1000. The energy storage device 1000 is equipped with a group of chemical batteries. The chemical elements in the chemical batteries are mainly used as energy storage media. The charging and discharging process is accompanied by chemical reactions or changes in the energy storage medium. Simply put, the electricity generated by wind and solar energy is stored in the chemical batteries. When the use of external electricity reaches a peak, the stored electricity is released for use, or transferred to places where electricity is scarce for use.

[0026] Currently, energy storage (i.e., energy storage) has a wide range of application scenarios, including (wind and solar) power generation-side energy storage, grid-side energy storage, base station-side energy storage, and user-side energy storage. The corresponding types of energy storage devices 1000 include:

[0027] (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, achieving load matching of electricity in time and space, enhancing the ability to absorb renewable energy, and are of great significance in grid system backup, alleviating peak load power supply pressure, and peak and frequency regulation;

[0028] (2) Small and medium-sized energy storage cabinets used in industrial and commercial energy storage scenarios (banks, shopping malls, etc.) on the user side mainly operate in the "peak shaving and valley filling" mode. Since there is a large price difference in electricity prices 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, they release the electricity in the energy storage equipment for use, thereby saving electricity costs.

[0029] It should be noted that the above-mentioned energy storage containers, small and medium-sized energy storage cabinets, small household energy storage boxes and other equipment containing the energy storage device 1000 can be understood as electrical equipment.

[0030] Please refer to Figure 1, which is an application scenario diagram of the energy storage device provided in an embodiment of the present application. The energy storage device 1000 provided in an embodiment of the present application is applied to an energy storage system 5000, which includes a first power conversion device 4100 (photovoltaic panel), a second power conversion device 4200 (wind turbine), a first power user 3000 (grid), a second power user 2000 (base station) and an energy storage device 1000. The energy storage system 5000 also includes an energy storage cabinet, and the energy storage device 1000 is installed in the energy storage cabinet, which can be installed outdoors. Specifically, the first power conversion device 4100 can convert solar energy into electrical energy during periods of low electricity prices, and the energy storage device 1000 is used to store the electrical energy and supply it to the first power user 3000 or the second power user 2000 during peak electricity consumption, or to supply power when the first power user 3000 or the second power user 2000 is powered off / out of power. The second power conversion device 4200 can convert wind energy into electrical energy. The energy storage device 1000 is used to store this electrical energy and supply it to the first power device 3000 or the second power device 2000 during peak power consumption, or to supply power when the first power device 3000 or the second power device 2000 is powered off / out of power. The electrical energy can be transmitted using high-voltage cables.

[0031] It should be noted that the first electric device 3000 , the second electric device 2000 and other devices including the energy storage device 1000 can be understood as electric devices.

[0032] There may be multiple energy storage devices 1000, which are connected in series or in parallel. In this embodiment, "multiple" refers to two or more.

[0033] It is understood that the energy storage device 1000 may include, but is not limited to, single cells, battery modules, battery packs, and battery systems. The energy storage device 1000 provided in the embodiments of this application may be, but is not limited to, the products listed above, or may be implemented in other forms. The embodiments of this application do not impose strict limitations on the application of the energy storage device 1000. The embodiments of this application illustrate the energy storage device 1000 as a multi-cell battery.

[0034] Please refer to Figure 2, which is a schematic diagram of the structure of the energy storage device shown in Figure 1. The energy storage device 1000 includes a shell (not shown), an end cap assembly 100, and an electrode assembly 200. The shell has an opening, and the shell is provided with a receiving cavity. The electrode assembly 200 is received in the receiving cavity. The end cap assembly 100 covers the opening. The shell wraps around and around the bottom of the electrode assembly 200, and the shell is sealed to the end cap assembly 100. The electrode assembly 200 includes at least two pole cores, each of which includes a pole core body and a pole tab, which is connected to the pole core body.

[0035] For the convenience of description, the length direction of the end cap assembly shown in Figure 2 is defined as the X-axis direction, the width direction of the end cap assembly is defined as the Y-axis direction, and the thickness direction of the end cap assembly is defined as the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to each other. The directional terms such as "upper" and "lower" mentioned in the description of the embodiment of the present application are based on the description shown in Figure 2 of the specification, with the positive direction of the Z-axis being "up" and the negative direction of the Z-axis being "lower". It does not constitute a limitation on the energy storage device in actual application scenarios. The "same", "equal" or "parallel" used in the following text are allowed to have a certain tolerance.

[0036] Please refer to Figure 3, which is a schematic diagram of the exploded end cap assembly of the energy storage device shown in Figure 2. The end cap assembly 100 includes a lower plastic 30 and an end cap 40, and the lower plastic 30 is installed on the end cap 40. The end cap 40 in this embodiment is a plain aluminum part, and the lower plastic 30 is made of plastic material and is insulated. The end cap assembly 100 also includes an explosion-proof valve 70, which is installed on the end cap 40. The end cap assembly 100 also includes an upper plastic assembly 50 and an electrode pole 60. Specifically, the end cap 40 and the lower plastic 30 are stacked, and the lower plastic 30 is used to insulate the end cap 40 and the electrode assembly 200. The upper plastic assembly 50 and the end cap 40 are stacked, and the upper plastic assembly 50 is located on the side of the end cap 40 away from the lower plastic 30. The electrode pole 60 includes a first pole 61 and a second pole 62. The upper plastic assembly 50 includes a first upper plastic 51 and a second upper plastic 52, which are installed side by side at both ends of the end cover 40 along the length direction (X-axis direction) of the end cover assembly 100. The first upper plastic 51 and the second upper plastic 52 are both provided with through holes, which are used for the first pole 61 and the second pole 62 to pass through respectively. The first pole 61 and the second pole 62 are covered with sealing rings. It should be noted that, in this embodiment, the first pole 61 is the negative pole and the second pole 62 is the positive pole. In other embodiments, the first pole 61 may be the positive pole and the second pole 42 may be the negative pole.

[0037] In this embodiment, the end cap 40 includes an end cap body 41. The end cap body 41 is provided with a first through hole 411, a welding groove 414, a second through hole 412, and a liquid injection hole 413. Along the length direction (X-axis direction) of the end cap 40, the first through hole 411, the welding groove 414, the liquid injection hole 413, and the second through hole 412 are sequentially arranged.

[0038] A first through hole 411 and a second through hole 412 are provided at opposite ends of the end cap body 41. In this embodiment, the first through hole 411 and the second through hole 412 are respectively used to allow the first and second poles 61, 62 of the energy storage device 1000 to pass through. In other embodiments, the first through hole 411 may also be used to allow the second pole 62 to pass through, and the second through hole 412 may also be used to allow the first pole 61 to pass through.

[0039] The explosion-proof valve 70 is welded to the wall of the welding groove 414. When the internal pressure of the energy storage device 1000 is too high, the explosion-proof valve 70 automatically opens to release the pressure and prevent an explosion. The injection hole 413 is located between the welding groove 414 and the second through hole 412. During the injection process of the energy storage device 1000, the electrolyte is injected into the energy storage device 1000 through the injection hole 413 on the end cap 40.

[0040] 3 , the lower plastic 30 includes a first lower plastic 10 and a second lower plastic 20 . The first lower plastic 10 and the second lower plastic 20 are stacked with the end cap 40 , and the first lower plastic 10 and the second lower plastic 20 are butted together along the length of the end cap 40 . The sum of the lengths of the first lower plastic 10 and the second lower plastic 20 is less than or equal to the length of the end cap 40 . The widths of the first lower plastic 10 and the second lower plastic 20 are both the same as the width of the end cap 40 , with a certain tolerance allowed.

[0041] The embodiment of the present application is described by taking the first lower plastic 10 as an example. It should be understood that the second lower plastic 20 can also be used as a reference.

[0042] Please refer to FIG. 4 and FIG. 5 , FIG. 4 is a schematic structural diagram of the first lower plastic shown in FIG. 3 ; FIG. 5 is a schematic structural diagram of the first lower plastic shown in FIG. 4 at a second angle.

[0043] In this embodiment, the first lower plastic 10 includes a body 11, a boss 14, and a protrusion 15. Along the length direction of the first lower plastic (X-axis direction), the boss 14 and the protrusion 15 are connected to opposite ends of the body 11. The body 11 is generally a rectangular thin plate, which includes a body surface 111 and a second surface 112. Along the thickness direction of the first lower plastic 10 (Z-axis direction), the body surface 111 and the second surface 112 are arranged in back-to-back relationship. A retaining protrusion 12 is provided on the body 11. Specifically, the retaining protrusion 12 is protruding from the body surface 111 of the body 11 and is located at one end of the body 11 along the length direction (X-axis direction) of the first lower plastic 10.

[0044] In this embodiment, the body 11 further includes a post through-hole 113. This circular through-hole 113 extends through the body surface 111 and the second surface 112 and is located on the retaining protrusion 12. This through-hole 113 allows the first post 61 to pass through. In other embodiments, this through-hole 113 can also allow the second post 62 to pass through.

[0045] In this embodiment, the boss 14 is located at the end of the body 11 away from the retaining protrusion 12. The boss 14 includes a fourth surface 141 and a boss surface 142. Along the thickness direction (Z-axis direction) of the first lower plastic 10, the fourth surface 141 and the boss surface 142 are arranged in opposite directions. The boss surface 142 is flush with the main body surface 111 of the body 11; the fourth surface 141 is further away from the main body surface 111 than the second surface 112, that is, the fourth surface 141 protrudes from the second surface 112. It can be understood that the height of the boss 14 is greater than the thickness of the body 11.

[0046] A recess 13 is defined within the boss 14. The recess 13 is formed by the boss surface 142 being recessed toward the fourth surface 141. Along the thickness direction (Z-axis) of the first lower plastic 10, the orthographic projection of the recess 13 on the fourth surface 141 is located within the fourth surface 141. The depth of the recess 13 is greater than the thickness between the main body surface 111 and the second surface 112 of the first lower plastic 10. The recess 13 includes a first bottom wall 131 and first and second side walls 132 and 133 that are disposed opposite each other along the length direction (X-axis) of the first lower plastic 10. The surface of the first bottom wall 131 that faces the interior of the recess 13 serves as the bottom wall of the recess 13. The recess 13 also includes two end walls that are disposed opposite each other along the width direction (Y-axis) of the first lower plastic 10. The first bottom wall 131 includes a first sub-bottom wall 1311 and two second sub-bottom walls 1312. Along the width (Y-axis) of the first lower plastic member 10, the two second sub-bottom walls 1312 are located on opposite sides of the first sub-bottom wall 1311. The first sub-bottom wall 1311 is connected to the two end walls via the second sub-bottom walls 1312. Along the thickness (Z-axis) of the first lower plastic member 10, there is a height difference between the two second sub-bottom walls 1312 and the first sub-bottom wall 1311. The two second sub-bottom walls 1312 are further away from the second surface 112 of the body 11 relative to the first sub-bottom wall 1311. This means that two steps are formed between the first sub-bottom wall 1311 and the two second sub-bottom walls 1312.

[0047] The fourth surface 141 includes a first sub-surface 1411 and two second sub-surfaces 1412. The first sub-surface 1411 corresponds to the first sub-bottom wall 1311 in the thickness direction (Z-axis direction) of the first lower plastic member 10. The orthographic projection of the first sub-bottom wall 1311 is located within the first sub-surface 1411. The two second sub-surfaces 1412 correspond to the two second sub-bottom walls 1312 in the thickness direction (Z-axis direction) of the first lower plastic member 10. The orthographic projection of one second sub-bottom wall 1312 is located within one second sub-surface 1412, and the orthographic projection of the other second sub-bottom wall 1312 is located within the other second sub-surface 1412. The two second sub-surfaces 1412 are farther away from the second surface 112 of the body 11 than the first sub-surface 1411, and there is a height difference between the two second sub-surfaces 1412 and the first sub-surface 1411.

[0048] The first sub-bottom wall 1311 is provided with a through slot 1316. Along the thickness direction of the first lower plastic 10 (Z-axis direction), the through slot 1316 passes through two surfaces of the first sub-bottom wall 1311 that are arranged in opposite directions along the thickness direction. The through slot 1316 has two first walls 1316a and two second walls 1316b. The two first walls 1316a are arc-shaped and are arranged opposite to each other along the width direction of the first lower plastic 10 (Y-axis direction). The two second walls 1316b are connected between the two first walls 1316a and are arranged opposite to each other along the length direction of the first lower plastic 10 (X-axis direction). It can be understood that the overall outline of the through slot 1316 is an "elliptical runway" shape.

[0049] The through-slot 1316 is provided with a plurality of first ribs 1313 and second ribs 1314. The plurality of first ribs 1313 are arranged side by side and spaced apart along the width direction (Y-axis) of the first lower plastic 10. Each first rib 1313 connects two second walls 1316b of the through-slot 1316 that oppose each other along the length direction (X-axis) of the first lower plastic 10. The second rib 1314 extends through the plurality of first ribs 1313 along the width direction (Y-axis) of the first lower plastic 10 and connects two first walls 1316a of the through-slot 1316 that oppose each other along the width direction (Y-axis) of the first lower plastic 10. It will be appreciated that the plurality of first ribs 1313 and second ribs 1314 form a plurality of sub-slots within the through-slot 1316. In this embodiment, the number of second ribs 1314 is one; in other embodiments, the number of second ribs 1314 may be two or more.

[0050] Each second sub-bottom wall 1312 is provided with ventilation holes 1315. These holes 1315 extend through the two oppositely facing surfaces of the second sub-bottom wall 1312 along the thickness direction (Z-axis) of the first lower plastic member 10. The ventilation holes 1315 are arranged in a matrix. In this embodiment, the ventilation holes 1315 are circular, but other shapes are also possible.

[0051] Please refer to Figure 6, which is a schematic cross-sectional view of the ventilation hole shown in Figure 4. In this embodiment, the walls of the ventilation hole 1315 are inclined, and the diameter of the ventilation hole 1315 gradually decreases along the direction from the main body surface 111 to the second surface 112. In other words, the walls of the ventilation hole 1315 are inclined to form a guiding slope.

[0052] It can be understood that the first groove bottom wall 131 , the plurality of first ribs 1313 , the second ribs 1314 and the plurality of air holes 1315 form an explosion-proof fence. The explosion-proof fence is opposite to the explosion-proof valve 70 .

[0053] It is understandable that in this embodiment, the hole wall of the air vent 1315 forms an inclined guiding slope. When the energy storage device 1000 is shaken or inverted, causing the electrolyte to splash onto the two second sub-bottom walls 1312 of the recess 13 of the first lower plastic 10, or the electrolyte splashes onto the main body surface 111 and then flows onto the two second sub-bottom walls 1312, the electrolyte can be guided by the guiding slope of the air vent 1315 to quickly flow back into the electrode assembly 200, thereby improving the wettability of the electrode assembly 200 and preventing the electrolyte from staying on the main body surface 111 of the first lower plastic 10 or the two second sub-bottom walls 1312 and being unable to participate in the electrochemical reaction, resulting in electrolyte waste.

[0054] In addition, the position of the injection molding mold of the lower plastic 30 corresponding to the vent hole 1315 is a conical protrusion. When the lower plastic 30 is demolded, the conical protrusion separates in a direction away from the lower plastic 30. The outer peripheral surface of the conical protrusion can be separated from the hole wall of the vent hole 1315 of the lower plastic 30 in an instant, avoiding the conical protrusion from contacting the hole wall of the vent hole 1315 during the process of exiting the vent hole 1315, causing film pulling. Therefore, the yield rate of the injection molding of the lower plastic 30 is improved, thereby reducing production costs.

[0055] Please continue to refer to Figures 4 and 5. In this embodiment, the protrusion 15 is located at one end of the body 11 close to the retaining protrusion 12. The protrusion 15 includes a third surface 151 and a raised surface 152. Along the thickness direction of the first lower plastic 10 (Z-axis direction), the third surface 151 and the raised surface 152 are arranged in back-to-back relationship. The raised surface 152 is flush with the main body surface 111 of the main body 11; the third surface 151 is farther away from the main body surface 111 than the second surface 112, that is, the third surface 151 protrudes from the second surface 112. It can be understood that the height of the protrusion 15 is greater than the thickness of the main body 11. Along the thickness direction of the first lower plastic 10 (Z-axis direction), the third surface 151 is flush with the fourth surface 141.

[0056] The fourth surface 141 of the boss 14, the second surface 112 of the body 11, and the third surface 151 of the protrusion 15 form the lower plastic surface 102 of the first lower plastic member 10. The boss surface 142 of the boss 14, the main surface 111 of the body 11, and the raised surface 152 of the protrusion 15 form the first surface 101 of the first lower plastic member 10. Along the length of the first lower plastic member 10, the third surface 151 is located at one end of the second surface 112. Along the length of the first lower plastic member 10, the fourth surface 141 is located at the end of the second surface 112 away from the third surface 151.

[0057] In this embodiment, the protrusion 15 includes a stopper 153 and two side stops 154. The stopper 153 is a rectangular block. The two side stops 154 are respectively disposed at opposite ends of the stopper 153 along the width direction (Y-axis) of the first lower plastic 10. One end of each side stopper 154 is fixed to the stopper 153, and the other end extends toward the boss 14 along the length direction (X-axis) of the first lower plastic 10. The stopper 153 and the two side stops 154 form a U-shaped structure. In this embodiment, the protrusion 15 can be integrally formed with the body 11.

[0058] In this embodiment, a groove 16 is defined within the stopper 153. The groove 16 extends from the raised surface 152 into the stopper 153 along the thickness direction (Z-axis) of the first lower plastic member 10. The groove 16 includes a second bottom wall 161, as well as first and second sidewalls 162 and 163 disposed opposite each other along the length direction (X-axis) of the first lower plastic member 10. The surface of the second bottom wall 161 facing the interior of the groove 16 serves as the bottom wall of the groove 16. The surface of the first sidewall 162 facing the interior of the groove 16 serves as the first wall of the groove 16. The surface of the second sidewall 163 facing the interior of the groove 16 serves as the second wall of the groove 16. The first and second walls are spaced apart and opposed to each other along the length direction of the first lower plastic member 10. The groove 16 also includes two end walls disposed opposite each other along the width direction (Y-axis) of the first lower plastic member 10. The groove 16 is provided in the corresponding area of ​​the stopper 153 to ensure the depth of the groove 16 , which can save the material of the first lower plastic 10 and help save manufacturing costs. It can also reduce the weight of the first lower plastic 10 and help the lightweight design of the energy storage device 1000 .

[0059] It can be understood that the groove 16 is located at one end of the first lower plastic 10 in the length direction, and the opening of the groove 16 is located on the first surface 101 , and the recess 13 is located at the other end of the first lower plastic 10 in the length direction, and the opening of the recess 13 is located on the first surface 101 .

[0060] Specifically, along the thickness direction (Z-axis direction) of the first lower plastic 10 , the orthographic projection of the groove 16 on the third surface 151 completely coincides with the orthographic projection of the stopper 153 on the third surface 151 , or the orthographic projection of the groove 16 on the third surface 151 is located within the orthographic projection of the stopper 153 on the third surface 151 ; it can be understood that the contour of the groove 16 is the same as or similar to the outer contour of the stopper 153 .

[0061] The groove 16 is provided with a plurality of reinforcing ribs 164. These ribs 164 protrude from the second groove bottom wall 161 and connect between the first groove side wall 162 and the second groove side wall 163, extending along the width direction (Y-axis) of the first lower plastic 10. This means that the plurality of reinforcing ribs 164 are fixedly connected to the groove bottom wall of the groove 16 and fixedly connected between the first wall and the second wall. The plurality of reinforcing ribs 164 are spaced apart in sequence along the width direction (Y-axis) of the first lower plastic 10. The plurality of reinforcing ribs 164 are arranged in a spaced-apart arrangement, dividing the groove 16 into a plurality of guide grooves 165. The plurality of guide grooves 165 are arranged in a sequence along the width direction (Y-axis) of the first lower plastic 10. The plurality of reinforcing ribs 164 enhances the strength of the groove 16. Specifically, in this embodiment, the number of reinforcing ribs 164 is five, and the five reinforcing ribs 164 divide the groove 16 into six guide grooves 165 of equal volume. The groove sidewalls of the guide groove 165 are actually formed by the groove sidewalls of the groove 16 , the groove end walls of the groove 16 and a plurality of reinforcing ribs 164 .

[0062] The first lower plastic 10 is also provided with a plurality of guide holes 166. These guide holes 166 are disposed on the second bottom wall 161 of the groove 16. The guide holes 166 extend along the thickness direction (Z-axis direction) of the first lower plastic 10, penetrating two oppositely facing surfaces of the second bottom wall 161 of the groove 16. The guide holes 166 are spaced apart along the length of the groove 16. Specifically, in this embodiment, the guide holes 166 are arranged within the guide groove 165. There are six guide holes 166, with each guide groove 165 having one guide hole 166, and each guide hole 166 extends through the bottom wall of a guide groove 165. During injection or use, the guide holes 166 can guide electrolyte splashed onto the main surface 111 of the first lower plastic 10 through the groove 16, through the plurality of guide holes 166, and then back into the electrode assembly 200 through the guide holes 166, achieving electrolyte reflux and reuse. This prevents electrolyte from remaining on the main surface 111 of the first lower plastic 10, avoids accumulation of liquid on the main surface 111 of the first lower plastic 10 and in the groove 16, and improves the wettability of the electrode assembly 200. The walls of the guide holes 166 are inclined, and the diameter of the guide holes 166 gradually decreases from the first surface 101 to the second surface 112. That is, the walls of the guide holes 166 are inclined to form a guiding slope.

[0063] It is understandable that in this embodiment, the hole wall of the guide hole 166 forms a guiding slope. When the energy storage device 1000 is shaken or inverted, causing the electrolyte to splash onto the second groove bottom wall 161 of the groove 16, or the electrolyte splashes onto the main body surface 111 of the first lower plastic 10 and then flows into the groove 16, the electrolyte can quickly flow back to the electrode assembly 200 under the action of the guiding slope formed by the hole wall of the guide hole 166, thereby improving the wettability of the electrode assembly 200, preventing the electrolyte from staying on the main body surface 111 of the first lower plastic 10 or in the groove 16 and being unable to participate in the electrochemical reaction, thereby avoiding waste of electrolyte.

[0064] In addition, the injection molding mold of the lower plastic 30 has a conical protrusion at the position corresponding to the guide hole 166. When the lower plastic 30 is demolded, the conical protrusion separates in a direction away from the lower plastic 30. The outer peripheral surface of the conical protrusion can be separated from the hole wall of the guide hole 166 of the lower plastic 30 in an instant, preventing the conical protrusion from contacting the hole wall of the guide hole 166 during the process of exiting the guide hole 166, thereby preventing the film from being pulled. Therefore, the yield rate of the injection molding of the lower plastic 30 is improved, thereby reducing production costs.

[0065] The lower plastic 30 is manufactured through an injection molding process. During injection molding, molten plastic is injected into the mold cavity through the injection port of a mold (not shown). After the molten plastic fills the mold cavity, the high-temperature molten plastic cools down and solidifies, and then the mold is removed to form the lower plastic 30. The surface of the lower plastic 30 forms an injection portion. From the perspective of the mold, the injection portion corresponds to the position of the mold's injection port.

[0066] It should be noted that, in order to improve the injection molding efficiency, the mold is usually provided with a mold cavity for simultaneously molding multiple first lower plastics 10, and the mold cavities of the multiple first lower plastics 10 are arranged in a matrix. Each mold cavity in the mold is correspondingly provided with an injection port. When the plastic liquid is injected into the mold, the plastic liquid first enters the plastic liquid flow channel in the mold, and then the plastic liquid is diverted and flows to the injection ports of the mold cavities of the multiple first lower plastics 10, and enters the interior of the mold cavity through the injection port. In order to allow the plastic liquid to be injected into the multiple first lower plastic 10 mold cavities arranged in a matrix, the plastic liquid flow channel is higher than the multiple first lower plastic 10 mold cavities, so that the plastic liquid can flow vertically downward into the multiple first lower plastic 10 mold cavities after being diverted from the plastic liquid flow channel.

[0067] 4 and 5 , in this embodiment, the first lower plastic 10 has a first injection portion 17 and a second injection portion 18 .

[0068] In this embodiment, the first injection portion 17 is located between two adjacent guide holes 166 in the groove 16. The first injection portion 17 includes a first opening end 171 and a first injection protrusion 172.

[0069] A first opening end 171 is provided on the third surface 151. Along the thickness direction of the first lower plastic member 10, the orthographic projection of the first opening end 171 on the first surface 101 at least partially overlaps the orthographic projection of a reinforcing rib 164 on the first surface 101. It can be understood that the first opening end 171 corresponds to a reinforcing rib 164. Specifically, the first opening end 171 corresponds to the outermost reinforcing rib 164 in the groove 16. In this embodiment, the first opening end 171 is a groove, caused by the shrinkage of the plastic liquid at the injection port after cooling and solidification. During the injection molding process of the first lower plastic member 10, the first opening end 171 corresponds to the injection port of the mold.

[0070] It should be noted that during the injection molding process of the first lower plastic 10, the first opening end 171 corresponds to the injection port of the mold cavity of the first lower plastic 10. In other embodiments, after the plastic is molded in the mold, if there is a slight excess of plastic, a protrusion will remain at the injection port, that is, the first opening end 171 is a protrusion; if there is a slight shortage of plastic, a groove will be formed at the injection port, that is, the first opening end 171 is a groove. In the case where the first opening end 171 is a protrusion, the protrusion can be retained or sheared or polished off after demolding. In this case, the protrusion will not be left on the final product, and the first opening end 171 will form a planar structure flush with the other parts, and the roughness of the planar structure formed by the first opening end 171 is different from the roughness of the third surface 151.

[0071] The first injection molding protrusion 172 protrudes from the second bottom wall 161 of the groove 16, that is, the first injection molding protrusion 172 protrudes from the bottom wall of the groove 16. Along the thickness direction (Z-axis direction) of the first lower plastic member 10, the first injection molding protrusion 172 corresponds to the first opening end 171, and the orthographic projection of the first injection molding protrusion 172 on the first surface 101 overlaps the orthographic projection of the first opening end 171 on the first surface 101. The first injection molding protrusion 172 is located between the second bottom wall 161 of the groove 16 and the reinforcing rib 164 corresponding to the first opening end 171. It can be understood that the reinforcing rib 164 corresponding to the first opening end 171 is connected to the second bottom wall 161 of the groove 16 via the first injection molding protrusion 172, and the first injection molding protrusion 172 is connected to the reinforcing rib 164 corresponding to the first opening end 171. Along the thickness direction (Z-axis direction) of the first lower plastic 10 , the height h1 of the first injection protrusion 172 is 0.25 mm to 0.45 mm, which is equivalent to the height h1 of the first injection protrusion 172 satisfying 0.25 mm≤h1≤0.45 mm.

[0072] In other embodiments, the first opening end 171 may also be disposed on the second surface 112 of the body 11 , as long as the first opening end 171 and the first injection protrusion 172 correspond to each other along the thickness direction (Z-axis direction) of the first lower plastic 10 .

[0073] In this embodiment, the second injection molding portion 18 is located on a side of any second sub-bottom wall 1312 that is close to the first sub-bottom wall 1311. Along the width direction (Y-axis) of the first lower plastic member 10, the second injection molding portion 18 and the first injection molding portion 17 are located on the same side of the first lower plastic member 10. The second injection molding portion 18 includes a second opening end 181 and a second injection molding protrusion 182.

[0074] The second open end 181 is disposed on the fourth surface 141. Along the thickness direction of the first lower plastic member 10, the orthographic projection of the second open end 181 on the first surface 101 at least partially overlaps the orthographic projection of a step on the first surface 101. This means that the second open end 181 corresponds to a step. Specifically, in this embodiment, the second open end 181 is a groove, caused by the shrinkage of the plastic liquid at the injection port after cooling and solidification. During the injection molding process of the first lower plastic member 10, the second open end 181 corresponds to the injection port of the mold.

[0075] It should be noted that during the injection molding process of the first lower plastic 10, the second open end 181 corresponds to the injection port of the mold cavity of the first lower plastic 10. In other embodiments, after the plastic is molded in the mold, if there is a slight excess of plastic, a lower protrusion will remain at the injection port, that is, the second open end 181 is a protrusion; if there is a slight shortage of plastic, a groove will be formed at the injection port, that is, the second open end 181 is a groove. In the case where the second open end 181 is a protrusion, the protrusion can be retained or sheared or polished off after demolding. In this case, the protrusion will not be left on the final product, and the second open end 181 will form a planar structure flush with the other parts, and the roughness of the planar structure formed by the second open end 181 is different from the roughness of the fourth surface 141.

[0076] The second injection molding protrusion 182 is provided protrudingly from the second sub-bottom wall 1312, that is, the second injection molding protrusion 182 is provided protrudingly from the bottom wall surface of the groove of the recess 13. Along the thickness direction (Z-axis direction) of the first lower plastic 10, the second injection molding protrusion 182 corresponds to the second opening end 181, and the orthographic projection of the second injection molding protrusion 182 on the first surface 101 overlaps the orthographic projection of the second opening end 181 on the first surface 101. The second injection molding protrusion 182 is connected to the step corresponding to the second opening end 181. Along the thickness direction (Z-axis direction) of the first lower plastic 10, the height of the second injection molding protrusion 182 is 0.25mm to 0.45mm, which means that the height h2 of the second injection molding protrusion 182 satisfies 0.25mm≤h2≤0.45mm.

[0077] In other embodiments, the second opening end 181 may also be disposed on the second surface 112 of the body 11 , as long as the second opening end 181 and the second injection protrusion 182 correspond to each other along the thickness direction (Z-axis direction) of the first lower plastic 10 .

[0078] It should be noted that, in other embodiments, along the thickness direction (Z-axis direction) of the first lower plastic 10 , the first opening end 171 may also correspond to another outermost reinforcing rib 164 in the groove 16 ; the second opening end 181 may also correspond to a step between another second sub-bottom wall 1312 and the first sub-bottom wall 1311 .

[0079] Continuing to refer to Figures 4 and 5, in this embodiment, the first lower plastic 10 further includes a first anti-overflow groove 191 and a second anti-overflow groove 192. The first anti-overflow groove 191 is provided on the third surface 151 and is recessed into the third surface 151 along the thickness direction (Z-axis direction) of the first lower plastic 10. Along the thickness direction (Z-axis direction) of the first lower plastic 10, the depth d1 of the first anti-overflow groove 191 is 0.32 mm to 0.52 mm, which means that the depth d1 of the first anti-overflow groove 191 satisfies 0.32 mm ≤ d1 ≤ 0.52 mm. The first anti-overflow groove 191 surrounds the first opening end 171 and is located on the side of the first opening end 171 facing the third surface 151, and is in communication with the first opening end 171. The first anti-overflow groove 191 is recessed into the third surface 151. Along the thickness direction (Z-axis direction) of the first lower plastic 10 , the orthographic projection of the first opening end 171 on the first surface 101 is located within the orthographic projection of the first anti-overflow groove 191 on the first surface 101 .

[0080] The second anti-overflow groove 192 is provided on the fourth surface 141, along the thickness direction (Z-axis direction) of the first lower plastic 10, and the second anti-overflow groove 192 is recessed in the fourth surface 141. Specifically, the second anti-overflow groove 192 is recessed in one of the second sub-surfaces 1412. Along the thickness direction (Z-axis direction) of the first lower plastic 10, the depth d2 of the second anti-overflow groove 192 is 0.32mm to 0.52mm, which is equivalent to the depth d2 of the second anti-overflow groove 192 satisfying 0.25mm≤h1≤0.45mm. The second anti-overflow groove 192 surrounds the second opening end 181. The second anti-overflow groove 192 is located on the side of the second opening end 181 facing the fourth surface 141 and is connected to the second opening end 181. The second anti-overflow groove 192 is recessed in the fourth surface 141. Along the thickness direction (Z-axis direction) of the first lower plastic 10 , the orthographic projection of the second opening end 181 on the first surface 101 is located within the orthographic projection of the second anti-overflow groove 192 on the first surface 101 .

[0081] It is understood that in this embodiment, the first anti-overflow groove 191 is provided on the third surface 151, and the first anti-overflow groove 191 surrounds the first open end 171. This can prevent the sharp cracks of the plastic rod from scratching the pole core body or the pole lug on the pole core after the plastic is formed in the mold (i.e., a protrusion). This could cause an internal short circuit in the energy storage device 1000. The second anti-overflow groove 192 is provided on the fourth surface 141, and the second anti-overflow groove 192 surrounds the second open end 181. This can prevent the sharp cracks of the plastic rod from scratching the pole core body or the pole lug on the pole core after the plastic is formed in the mold (i.e., a protrusion).

[0082] Furthermore, in this embodiment, since the first opening end 171 and the second opening end 181 are respectively provided on the third surface 151 and the fourth surface 141 , the position of the injection port in the mold corresponds to the positions of the first opening end 171 and the second opening end 181 . The plastic liquid, after being diverted from the plastic liquid flow channel, can flow vertically downward and directly into the mold cavity of the first lower plastic 10 through the injection port of the mold cavity of the first lower plastic 10 . Compared with locating the opening end on the side wall of the first lower plastic 10, the position of the injection port corresponds to the position of the opening end. After the plastic liquid is diverted from the plastic liquid flow channel and flows vertically downward to the height of the injection port, it needs to make a right-angle turn and then enter the interior of the mold cavity from the side of the first lower plastic 10 mold cavity through the injection port. That is, a channel of sufficient length needs to be reserved on the side of the first lower plastic 10 mold cavity to allow the plastic liquid to enter the mold cavity through the injection port. In the embodiment of the present application, no channel for the flow of plastic liquid is required between two adjacent first lower plastic 10 mold cavities, that is, the distance between two adjacent first lower plastic 10 mold cavities can be smaller, and the matrix arrangement of the molding mold cavities of the first lower plastic 10 can be designed to be more compact, that is, more mold cavities of the first lower plastic 10 can be arranged per unit area in the mold, and the number of first lower plastics 10 injection molded at one time is greater, thereby improving the production efficiency of the first lower plastic 10.

[0083] The first opening end 171 and the second opening end 181 are respectively provided on the third surface 151 and the fourth surface 141. The positions of the injection ports in the mold correspond to the positions of the first opening end 171 and the second opening end 181. That is, the first opening end 171 and the second opening end 181 respectively correspond to two injection ports. After the plastic liquid enters the mold cavity of the first lower plastic 10, the plastic liquid has a larger flow channel space in the thickness direction of the first lower plastic 10. Multiple diversion paths can be provided along the thickness direction of the first lower plastic 10, which can improve the diversion efficiency of the plastic liquid in the mold cavity of the first lower plastic 10, thereby improving the production efficiency of the first lower plastic 10.

[0084] In addition, corresponding to the first injection protrusion 172, an injection recess is provided in the mold cavity of the first lower plastic 10 for molding the first injection protrusion 172. Since the position of an injection port in the mold corresponds to the position of the first opening end 171, an injection recess in the mold cavity corresponds to the injection port at the position of the first opening end 171. When the plastic liquid enters the mold cavity of the first lower plastic 10 through an injection port, the injection recess corresponding to the first injection protrusion 172 can provide a storage space, so that the plastic liquid entering the mold cavity of the first lower plastic 10 through an injection port can be directly diverted to the surrounding areas after accumulating in the storage space, thereby improving the diversion efficiency of the first lower plastic 10 and further improving the production efficiency of the first lower plastic 10; and preventing the plastic liquid from entering the mold cavity through an injection port and colliding with the cavity wall of the mold cavity directly opposite the injection port and splashing to the outside of the mold cavity, affecting the efficiency of the plastic liquid filling the mold cavity. Furthermore, the plastic liquid can be quickly dispersed to other areas through the flow channels in the areas where the reinforcing ribs 164 are located (the reinforcing ribs serve as flow channels when the plastic liquid is injected), thereby further improving the flow efficiency of the plastic liquid and thereby shortening the injection molding time.

[0085] Corresponding to the second injection protrusion 182, another injection recess is provided in the mold cavity of the first lower plastic 10 for molding the second injection protrusion 182. Since the position of the other injection port in the mold corresponds to the position of the second opening end 181, the other injection recess in the mold cavity corresponds to the injection port at the position of the second opening end 181. When the plastic liquid enters the mold cavity of the first lower plastic 10 through the other injection port, the injection recess corresponding to the second injection protrusion 182 can provide a storage space, so that the plastic liquid entering the mold cavity of the first lower plastic 10 through the other injection port can be directly diverted to the surrounding areas after accumulating in the storage space, thereby improving the diversion efficiency of the first lower plastic 10 and further improving the production efficiency of the first lower plastic 10; and preventing the plastic liquid from entering the mold cavity through the other injection port and colliding with the cavity wall of the mold cavity directly facing the other injection port and splashing to the outside of the mold cavity, affecting the efficiency of the plastic liquid filling the mold cavity. In addition, the plastic liquid can be quickly dispersed to other areas through the flow channel in the area where the step is located (the step serves as the flow channel when the plastic liquid is injected), further improving the flow efficiency of the plastic liquid and thus shortening the injection molding time.

[0086] The first injection molding part 17 and the second injection molding part 18 are respectively located at opposite ends of the first lower plastic 10 along the length direction. After the plastic liquid enters the mold cavity of the first lower plastic 10 from the injection ports corresponding to the positions of the first injection molding part 17 and the second injection molding part 18, it can flow from the opposite ends of the first lower plastic 10 along the length direction to the middle. The corresponding cavity of the main body 11 can be provided with a longer flow channel, thereby increasing the flow channel length of the plastic liquid and further improving the production efficiency of the first lower plastic 10. It avoids setting a complex flow channel with many corners that affects the flow rate of the plastic liquid.

[0087] In addition, in this embodiment, the first anti-overflow groove 191 is recessed in the third surface 151, the first anti-overflow groove 191 surrounds the first opening end 171, the second anti-overflow groove 192 is recessed in the fourth surface 141, and the second anti-overflow groove 192 surrounds the second opening end 181. After the plastic liquid enters the mold cavity from the injection ports corresponding to the positions of the first opening end 171 and the second opening end 181, the plastic liquid can flow directly along the thickness direction of the first lower plastic 10. After the plastic liquid enters the mold cavity from the injection ports corresponding to the positions of the opening ends, it does not need to immediately pass through a right-angle turn to form the protrusion 15 and the boss 14. The plastic liquid flows more smoothly, avoiding the high-speed flowing plastic liquid at the liquid inlet from colliding with the mold and damaging the mold, thereby improving the service life of the mold and reducing the production cost of the first lower plastic 10.

[0088] Please refer to Figures 7a, 7b, and 7c. Figure 7a is a schematic diagram of the first lower plastic member shown in Figure 4 from a third angle, with the second and third groups of second ejector pins omitted. Figure 7b is a schematic diagram of the first lower plastic member shown in Figure 4 from a third angle, with the first and third groups of second ejector pins omitted. Figure 7c is a schematic diagram of the first lower plastic member shown in Figure 4 from a third angle, with the first and second groups of second ejector pins omitted. In this embodiment, the first lower plastic member 10 is provided with a plurality of first ejector pins S1, a plurality of second ejector pins S2, and a plurality of third ejector pins S3. The plurality of first ejector pins S1 are disposed on the main body surface 111 of the main body 11, between the recess 13 and the groove 16. The plurality of first ejector pins S1 are spaced apart from one another. The plurality of second ejector pins S2 are spaced apart from one another on the bottom surface of the first groove bottom wall 131 of the recess 13. The plurality of third ejector pins S3 are spaced apart from one another on the bottom surface of the second groove bottom wall 161 of the groove 16. The multiple first ejector pins S1, the multiple second ejector pins S2, and the multiple third ejector pins S3 are all symmetrical about the midline of the width direction of the first lower plastic 10. The multiple ejector pins are the locations where ejectors (not shown) abut after the first lower plastic 10 is molded in the mold, thereby ejecting the molded first lower plastic 10 from the mold. The midline is a straight line extending along the length (X-axis) of the first lower plastic 10 and located in the middle of the width (Y-axis) of the first lower plastic 10. The midline is a virtual line set for convenience and does not actually exist on the first lower plastic 10.

[0089] It should be noted that in the embodiments of the present application, the ejector portion is the final product structure of the first lower plastic 10, formed by the ejector pin applying an ejection force to the main surface 111 of the main body 11. When the ejector pin has not yet contacted the first lower plastic 10, that is, before the demolding operation is performed, the first lower plastic 10 may not have the ejector portion formed. Of course, in some embodiments, the ejector portion structure may also be provided before demolding, that is, the ejector portion structure is formed on the first lower plastic 10 when the ejector pin has not yet contacted the first lower plastic 10.

[0090] In this embodiment, a plurality of first ejector portions S1 are located on the main body surface 111 of the main body 11. The plurality of first ejector portions S1 are divided into a plurality of groups. Each group contains at least one first ejector portion S1, and the first ejector portions S1 in each group are spaced apart along the width direction (Y-axis direction) of the first lower plastic 10 and are symmetrical relative to the center line. The plurality of groups are spaced apart along the length direction (X-axis direction) of the first lower plastic 10. The number of first ejector portions S1 in each group can be an odd number or an even number. Specifically, when the number of first ejector portions S1 in a group is an odd number, along the width direction (Y-axis direction) of the first lower plastic 10, one of the first ejector portions S1 is located on the center line and is symmetrical relative to the center line; the remaining first ejector portions S1 are evenly distributed on both sides of the center line and are symmetrical relative to the center line. When the number of first ejector portions S1 in a group is an even number, along the width direction (Y-axis direction) of the first lower plastic 10, all the first ejector portions S1 are evenly distributed on both sides of the center line and are symmetrical relative to the center line. Illustratively, there are two first ejector parts S1 in the first group S1.1, two first ejector parts S1 in the second group S1.2, one first ejector part S1 in the third group S1.3, and three first ejector parts S1 in the fourth group S1.4.

[0091] Among them, the two first ejector parts S1 in the first group S1.1 are respectively distributed on opposite sides of the pole through hole 113 along the width direction (Y-axis direction) of the first lower plastic 10. The two first ejector parts S1 in the second group S1.2 are respectively distributed on the two side edges of the body 11 along the width direction. The first ejector parts S1 in the third group S1.3 are distributed on the side of the holding protrusion 12 facing away from the groove 16. The three first ejector parts S1 in the fourth group S1.4 are distributed on the side of the recess 13 close to the holding protrusion 12, and the three first ejector parts S1 are spaced apart along the width direction (Y-axis direction) of the first lower plastic 10, wherein the two first ejector parts S1 are located on the two side edges of the body 11 along the width direction.

[0092] It is understood that the first ejector portions S1 of the first group S1.1 and the first ejector portions S1 of the third group are both distributed on the sides of the retaining protrusion 12, and the two first ejector portions S1 of the first group S1.1 and the first ejector portions S1 of the third group S1.3 are arranged in a triangle. The three first ejector portions S1 at the vertices of the triangle can help to uniformly demold the core. In view of the large resistance when demolding the retaining protrusion 12 and the fact that the provision of the pole through-hole 113 makes the retaining protrusion 12 easily damaged during demolding, the three first ejector portions S1 arranged in a triangle on the sides of the retaining protrusion 12 can improve the demolding stability of the retaining protrusion 12.

[0093] First ejector pins S1 are provided at opposite ends of the body 11 along its length, opposite sides of the body 11 along its width, and along the sides of the retaining protrusion 12. Multiple first ejector pins S1 are evenly distributed, ensuring that when they contact the body 11, they exert a uniform ejection force on the body 11, thereby ensuring uniform demolding. Multiple ejector pins simultaneously contact and move with the locations of the multiple first ejector pins S1 on the body surface 111 of the body 11, simultaneously applying a more uniform ejection force to the body surface 111. This prevents deformation of the body 11 caused by uneven ejection force, improves the uniformity of demolding the body 11, and thereby increases the injection yield of the first lower plastic 10.

[0094] Please refer to Figure 8, which is a partial cross-sectional structural diagram of the first lower plastic shown in Figure 4. The shape of the first ejector portion S1 is crater-shaped, with the middle portion being concave relative to the main body surface 111 and the edge protruding from the main body surface 111. The first ejector portion S1 includes a push surface, which is a surface formed by the middle portion of the first ejector portion S1 being concave inwardly toward the main body surface 111. Along the thickness direction (Z-axis direction) of the first lower plastic 10, the push surface faces the main body surface 111. The push surface is circular. Specifically, during the injection molding demolding process, when the plastic has not yet cooled to room temperature, when the ejector contacts the main body surface 111 and applies an ejection force, the pressure of the ejector acts on the main body surface 111, pushing the plastic out of the depression, and the plastic outside the ejector is squeezed by the plastic of the depressed portion, and will rise from the outer periphery of the ejector, thus forming the first ejector portion S1 in the shape of a crater. It can be understood that when the ejector contacts the main body surface 111 and applies an ejection force, the ejector contacts the push surface. The shapes of the second ejector portion S2 and the third ejector portion S3 are similar to those of the first ejector portion S1 and are also crater-shaped. The pushing surfaces of the second ejector portion S2 and the third ejector portion S3 are also circular, which will not be described in detail later.

[0095] In the embodiment of the present application, the crater-shaped portion S1 of the first ejector pin S1 is slightly concave relative to the main body surface 111. The depth of this concave portion is negligible compared to the thickness of the main body 11 (the dimension of the main body 11 in the Z-axis direction), and the specific depth of this concave portion is not limited. The edge of the crater-shaped portion is also slightly convex relative to the main body surface 111. The height of this convex portion is negligible compared to the thickness of the main body 11, and the specific height of this convex portion is not limited. In this way, the provision of the first ejector pin S1 does not adversely affect the structural strength of the main body 11, nor does it affect the function of the first lower plastic member 10.

[0096] Referring to Figures 7a, 7b, and 7c, in this embodiment, multiple second ejector pins S2 are distributed along the first sub-bottom wall 1311 and the two second sub-bottom walls 1312 of the recess 13. These second ejector pins S2 are symmetrical about the midline. The multiple second ejector pins S2 are divided into three groups: a first group S2.1, a second group S2.2, and a third group S2.3. The first group S2.1 consists of four second ejector pins S2, each located at the four corners of the first sub-bottom wall 1311. Each of the four second ejector pins S2 is symmetrical about the midline. The second group S2.2 includes three second ejector pins S2, two of which are located at the junction of the first rib 1313 and the second rib 1314, and are symmetrical about the midline. Another second ejector pin S2 is located on the side of the second rib 1314 away from the retaining protrusion 12 and is located on the midline, and is symmetrical about the midline. The third group S2.3 includes four second ejector pins S2, two of which are located on one second sub-bottom wall 1312, each located between four ventilation holes 1315, and spaced apart along the length of the first lower plastic member 10. Another two second ejector pins S2 are located on the other second sub-bottom wall 1312, each located between four second ventilation holes 1315, and spaced apart along the length of the first lower plastic member 10. The four second ejector pins S2 of the third group S2.3 are symmetrical in pairs relative to the midline.

[0097] It is understood that the four second ejector pins S2 of the first group S2.1 are located at the four corners of the first sub-bottom wall 1311, ensuring uniform force on the four corners during demolding. The two second ejector pins S2 of the second group S2.2 are located at the junction of the first rib 1313 and the second rib 1314, with one second ejector pin S2 located on the midline, ensuring uniform force on the entire first sub-bottom wall 1311 and preventing damage to the first sub-bottom wall 1311 due to high resistance during demolding. The four second ejector pins S2 of the third group S2.3 are located at the two second sub-bottom walls 1312, and the four second ejector pins S2 of the third group S2.3 are symmetrical, ensuring relatively balanced force on the two second sub-bottom walls 1312 during demolding, preventing deformation of the two second sub-bottom walls 1312 due to uneven force.

[0098] Please refer to Figure 7a. In this embodiment, a plurality of third ejector parts S3 are located on the second groove bottom wall 161 of the groove 16. A third ejector part S3 is provided in each guide groove 165. The plurality of third ejector parts S3 are spaced apart along the width direction (Y-axis direction) of the first lower plastic 10 and are symmetrical relative to the center line. Specifically, the number of third ejector parts S3 is 6. Among them, two third ejector parts S3 are respectively located on the side of the two outermost guide holes 166 away from the center line, and the two third ejector parts S3 are symmetrical relative to the center line; two third ejector parts S3 are respectively located on the side of the two middle guide holes 166 close to the center line, and the two third ejector parts S3 are symmetrical relative to the center line; the other two third ejector parts S3 are respectively located on the side of the two inner guide holes 166 close to the center line, and the two third ejector parts S3 are symmetrical relative to the center line.

[0099] It can be understood that by providing a third ejector portion S3 on the second groove bottom wall 161 of each guide groove 165 of the groove 16, when the third ejector portion S3 is used to demold the groove 16 as a whole, multiple third ejector portions S3 can evenly apply ejection force to each guide groove 165, thereby avoiding the guide groove 165 having a large demolding resistance so that the guide groove 165 cannot be demolded evenly.

[0100] It is understood that by providing multiple ejector pins on the first lower plastic 10 and aligning the ejector pins symmetrically with respect to the midline, the first lower plastic 10 can be uniformly ejected from the injection mold. The entire first lower plastic 10 is subjected to a uniform ejection force, enabling uniform demolding, thereby preventing deformation such as bending and twisting of the first lower plastic 10 due to uneven cooling. Furthermore, the first lower plastic 10 of the present embodiment can be ejected immediately after injection molding, eliminating the need to fully cool to room temperature in the mold before demolding, thereby improving production efficiency.

[0101] The above is a detailed introduction to the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for those skilled in the art, according to the idea of ​​the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A lower plastic, used for an end cap assembly of an energy storage device, wherein: The lower plastic has a first surface and a second surface, and the first surface and the second surface are arranged in opposite directions along the thickness direction of the lower plastic; The lower plastic is provided with a groove, a guide hole, a recess, a plurality of first ejector parts, a plurality of second ejector parts and a plurality of third ejector parts, the groove is located at one end of the lower plastic in the length direction, the groove bottom wall of the groove protrudes from the second surface, and the opening of the groove is located on the first surface, the guide hole passes through the groove bottom wall of the groove, and the aperture of the guide hole gradually decreases in the direction from the first surface to the second surface, the recess is located at the other end of the lower plastic in the length direction, the groove bottom wall of the recess protrudes from the second surface, and the opening of the recess is located on the first surface; The plurality of first ejector pins are all disposed on the first surface, and are located between the groove and the concave portion, and are spaced apart from each other. The plurality of second ejector pins are all disposed on the groove bottom wall surface of the concave portion, and are spaced apart from each other. The plurality of third ejector pins are all disposed on the groove bottom wall surface of the groove, and are spaced apart from each other. The plurality of first ejector pins, the plurality of second ejector pins, and the plurality of third ejector pins are all symmetrical with respect to the midline of the lower plastic in the width direction.

2. The lower plastic according to claim 1, wherein: The lower plastic also includes a third surface, which is located at one end of the second surface along the length direction of the lower plastic, and is located on the side of the groove facing away from the first surface along the thickness direction of the lower plastic, and the orthographic projection of the groove on the third surface is located within the third surface. The lower plastic is also provided with a first injection molding part, which includes a first opening end, and the first opening end is provided on the third surface; The groove has a first wall surface and a second wall surface, and the first wall surface and the second wall surface are opposite to each other and spaced apart along the length direction of the lower plastic; The lower plastic is also provided with a plurality of reinforcing ribs, and the plurality of reinforcing ribs are all fixedly connected to the bottom wall of the groove, and are fixedly connected between the first wall and the second wall, and the plurality of reinforcing ribs are sequentially spaced along the width direction of the lower plastic; Along the thickness direction of the lower plastic, the orthographic projection of the first opening end on the first surface at least partially covers the orthographic projection of one of the reinforcing ribs on the first surface.

3. The lower plastic according to claim 2, wherein: The lower plastic is also provided with a first anti-overflow groove, which is recessed in the third surface and connected to the first opening end. The first anti-overflow groove surrounds the first opening end, and along the thickness direction of the lower plastic, the orthographic projection of the first opening end on the first surface is located within the orthographic projection of the first anti-overflow groove on the first surface.

4. The lower plastic according to claim 3, wherein: Along the thickness direction of the lower plastic, the depth d1 of the first anti-overflow groove is in the range of 0.32 mm ≤ d1 ≤ 0.52 mm.

5. The lower plastic according to claim 2, wherein: The first injection molding part also includes a first injection molding protrusion, which is protruding from the bottom wall of the groove. Along the thickness direction of the lower plastic, the orthographic projection of the first injection molding protrusion on the first surface covers the orthographic projection of the first opening end on the first surface, and the first injection molding protrusion is connected to one of the reinforcing ribs.

6. The lower plastic according to claim 5, wherein: Along the thickness direction of the lower plastic, the height h1 of the first injection molding protrusion is in the range of 0.25 mm ≤ h1 ≤ 0.45 mm.

7. The lower plastic according to any one of claims 2 to 6, wherein: The lower plastic also includes a fourth surface. Along the length direction of the lower plastic, the fourth surface is located at an end of the second surface away from the third surface. Along the thickness direction of the lower plastic, the fourth surface is located at a side of the recess facing away from the first surface, and the orthographic projection of the recess on the fourth surface is located within the fourth surface. The lower plastic is further provided with a second injection molding portion, the second injection molding portion includes a second opening end portion, and the second opening end portion is provided on the fourth surface.

8. The lower plastic according to claim 7, wherein: The lower plastic also includes a second anti-overflow groove, which is recessed in the fourth surface and connected to the second opening end. The second anti-overflow groove surrounds the second opening end. Along the thickness direction of the lower plastic, the orthographic projection of the second opening end on the first surface is located within the orthographic projection of the second anti-overflow groove on the first surface.

9. The lower plastic according to claim 8, wherein: Along the thickness direction of the lower plastic, the depth d2 of the second anti-overflow groove is in the range of 0.32mm≤d2≤0.52mm.

10. The lower plastic according to claim 7, wherein: The recess has a first sub-bottom wall and two second sub-bottom walls, and along the width direction of the lower plastic, the two second sub-bottom walls are located on opposite sides of the first sub-bottom wall, and two steps are formed between the two second sub-bottom walls and the first sub-bottom wall respectively; Along the thickness direction of the lower plastic, an orthographic projection of the second opening end on the first surface at least partially covers an orthographic projection of one of the steps on the first surface.

11. The lower plastic according to claim 7, wherein: The second injection molding part also includes a second injection molding protrusion, which is convexly arranged on the bottom wall surface of the groove of the concave portion. Along the thickness direction of the lower plastic, the orthographic projection of the second injection molding protrusion on the first surface covers the orthographic projection of the second opening end on the first surface, and the second injection molding protrusion is connected to one of the steps.

12. The lower plastic according to claim 11, wherein: Along the thickness direction of the lower plastic, the height h2 of the second injection molding protrusion is in the range of 0.25 mm ≤ h2 ≤ 0.45 mm.

13. An end cap assembly, wherein: It includes an end cover, an explosion-proof valve and the lower plastic as described in any one of claims 1 to 12, wherein along the thickness direction of the end cover assembly, the lower plastic is stacked on one side of the end cover, and the first surface of the lower plastic faces the end cover, and along the thickness direction of the end cover assembly, the explosion-proof valve is opposite to the bottom wall of the recess.

14. An energy storage device, wherein: It comprises a shell, an electrode assembly and an end cap assembly as claimed in claim 13, wherein the shell has an opening, the shell is provided with a receiving cavity, the electrode assembly is received in the receiving cavity, and the end cap assembly is mounted on the shell and covers the opening.

15. An electrical device, wherein: The energy storage device as claimed in claim 14 is used to store electrical energy.

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