End cover assembly, energy storage device and electric equipment

Abstract

The utility model provides an end cover assembly, an energy storage device and electric equipment, which are used for improving the welding reliability of a compression ring and a pole and ensuring the use reliability of the energy storage device. The second mounting hole of the upper insulating part is communicated with the first mounting hole of the end cover, and the first mounting groove is arranged around the second mounting hole. The groove bottom wall surface of the first mounting groove is opposite to the opening of the first mounting groove, and the groove side wall surface is connected with the groove bottom wall surface. The pressing ring is installed in the first installation groove. A first exhaust channel is defined by the first surface of the pressing ring and the groove bottom wall face. The distance between the second end and the first end of the first exhaust channel is smaller than the length of the first exhaust channel. A second exhaust channel is defined by the peripheral side face of the pressing ring and the groove side wall face. The second exhaust channel communicates with the second end and the external environment. And the third mounting hole and the second mounting hole of the pressing ring are communicated with the first end. And the pole penetrates through the first mounting hole, the second mounting hole and the third mounting hole and is welded and fixed with the hole wall surface of the third mounting hole.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage, in particular to a end cover assembly, energy storage device and electric equipment. BACKGROUND

[0002] The secondary battery (Rechargeable battery) is also called as the rechargeable battery or the storage battery, which is the battery that can be activated by charging after discharging. The recyclable characteristics of the secondary battery make it gradually become the main power source of the electric equipment. With the gradually increasing demand for the secondary battery, the performance requirements of all aspects of the secondary battery are higher and higher, especially the reliability of the secondary battery. In the existing secondary battery, the compression ring is often assembled with the pole by welding. However, in the process of aligning and welding the compression ring with the pole, there are many welding defects such as blowhole or pinhole in the welding position of the pole and the compression ring, which reduces the welding reliability of the compression ring and the pole and affects the use reliability of the battery. CONTENT OF THE INVENTION

[0003] The present application provides an end cover assembly, an energy storage device and an electric equipment, which are used to improve the welding reliability of the compression ring and the pole and ensure the use reliability of the energy storage device.

[0004] In a first aspect, the present application provides an end cover assembly for an energy storage device, comprising an end cover, an upper insulating piece, a compression ring and a pole;

[0005] The end cover is provided with a first mounting hole, and the first mounting hole penetrates the end cover along the thickness direction of the end cover;

[0006] The upper insulating piece is mounted on one side of the end cover along the thickness direction of the end cover, the upper insulating piece is provided with a second mounting hole and a first mounting groove, the second mounting hole penetrates the upper insulating piece along the thickness direction of the upper insulating piece and communicates with the first mounting hole, the opening of the first mounting groove is located on the surface of the upper insulating piece away from the end cover, the first mounting groove is arranged around the second mounting hole and communicates with the second mounting hole, the first mounting groove has a groove bottom wall surface and a groove side wall surface, the groove bottom wall surface is arranged opposite to the opening of the first mounting groove, and the groove side wall surface is connected with the groove bottom wall surface and arranged around the groove bottom wall surface;

[0007] The compression ring is mounted in the first mounting groove, the compression ring has a first surface, a second surface and a circumferential surface, the first surface faces the groove bottom wall surface, the second surface is arranged opposite to the first surface, and the circumferential surface is connected between the first surface and the second surface;

[0008] The pressure ring is provided with a third mounting hole, the third mounting hole penetrates the first surface and the second surface, and is in communication with the second mounting hole;

[0009] The following three cases exist for the cooperation between the pressure ring and the upper insulating piece to form the first exhaust passage:

[0010] In the first case, the upper insulating piece is further provided with a first exhaust groove, the opening of the first exhaust groove is located on the groove bottom wall surface, the first exhaust groove is in communication with the second mounting hole, and the first exhaust groove and the first surface form a first exhaust passage; in the second case, the pressure ring is provided with a second exhaust groove, the opening of the second exhaust groove is located on the first surface, the second exhaust groove is in communication with the third mounting hole, and the second exhaust groove and the groove bottom wall surface form a first exhaust passage; in the third case, the upper insulating piece is further provided with a first exhaust groove, the opening of the first exhaust groove is located on the groove bottom wall surface, the first exhaust groove is in communication with the second mounting hole, the pressure ring is provided with a second exhaust groove, the opening of the second exhaust groove is located on the first surface, the second exhaust groove is in communication with the third mounting hole, and the second exhaust groove and the first exhaust groove form a first exhaust passage;

[0011] The first exhaust passage includes a first end and a second end, the first end is in communication with the second mounting hole and the third mounting hole, the second end is arranged opposite to the first end, and the distance between the second end and the first end is less than or equal to the length of the first exhaust passage;

[0012] The following two cases exist for the cooperation between the pressure ring and the upper insulating piece to form the second exhaust passage: in the first case, the upper insulating piece is provided with a convex part, the convex part is arranged on the groove side wall surface and abuts against the circumferential surface to form the second exhaust passage between the groove side wall surface and the circumferential surface; in the second case, the pressure ring is provided with a convex part, the convex part is arranged on the circumferential surface and abuts against the groove side wall surface to form the second exhaust passage between the circumferential surface and the groove side wall surface;

[0013] The second exhaust passage is in communication with the second end and the external environment;

[0014] The pole is arranged in the first mounting hole, the second mounting hole and the third mounting hole, and is welded and fixed with the hole wall surface of the third mounting hole.

[0015] During the welding process of the compression ring and the pole column, the gas between the pole column and the compression ring will be expanded under high temperature. The expanded gas can be discharged to the external environment along the first exhaust channel and the second exhaust channel. The gas will not be discharged from the molten weld, and welding defects such as blowholes or pinholes in the welding position of the pole column and the compression ring can be avoided, ensuring the welding reliability between the pole column and the compression ring, and further ensuring the assembly reliability of the end cover assembly. Moreover, since the distance between the second end and the first end is less than or equal to the length of the first exhaust channel, the channel path of the first exhaust channel can be extended. The first exhaust channel can not only discharge welding gas, but also reduce the entry of external water vapor into the position of the pole column, avoid water vapor erosion of the sealing ring to cause the sealing ring to fail, ensure the sealing reliability of the end cover assembly, and improve the service life of the energy storage device.

[0016] The design of the convex part not only realizes interference assembly between the compression ring and the first installation slot of the upper insulating part, ensures the assembly stability between the compression ring and the upper insulating part, but also ensures that the circumferential side surface of the compression ring and the slot side wall surface of the first installation slot are spaced apart, so that the second exhaust channel can be formed between the circumferential side surface of the compression ring and the slot side wall surface of the first installation slot.

[0017] In addition, since the first exhaust channel and the second exhaust channel can pass gas, temporary sealing caused by close fitting of the compression ring and the upper insulating part, and the upper insulating part and the end cover can be avoided. When the sealing ring fails, the end cover assembly can be detected in time by helium detection, ensuring the sealing reliability of the end cover assembly and avoiding the problem of liquid leakage of the energy storage device.

[0018] Furthermore, the design of the first exhaust groove and the second exhaust groove can increase the cross-sectional area of the first exhaust channel, which helps to increase the exhaust rate of welding gas when the compression ring is welded with the pole column, and improves the welding efficiency of the compression ring and the pole column.

[0019] Among them, the first exhaust channel has a plurality of first exhaust channels, and the plurality of first exhaust channels are arranged around the third installation hole to increase the exhaust rate of welding gas when the compression ring is welded with the pole column, and improve the welding efficiency of the compression ring and the pole column.

[0020] Among them, the first exhaust channel includes a first section, a corner section and a second section, the first section is in communication with the second installation hole and the third installation hole, and includes the first end, the second section is in communication with the second exhaust channel, and includes the second end and is spaced apart from the first section, and the corner section is connected between the first section and the second section.

[0021] The design of the corner section can extend the channel path of the first exhaust channel. The first exhaust channel can not only discharge welding gas, but also reduce the entry of external water vapor into the position of the pole column, avoid water vapor erosion of the sealing ring to cause the sealing ring to fail, ensure the sealing reliability of the end cover assembly, and improve the service life of the energy storage device.

[0022] The corner section comprises a plurality of curved portions, and the plurality of curved portions are connected in sequence, and the bending directions of at least two curved portions are opposite, so that the obstruction of external water vapor entering the position of the pole from the first exhaust channel is increased, water vapor erosion of the sealing ring is avoided, the sealing reliability of the end cover assembly is ensured, and the service life of the energy storage device is improved.

[0023] The maximum width of the first exhaust channel is greater than or equal to 0.01 mm and less than or equal to 5 mm, and / or the depth of the first exhaust channel is greater than or equal to 0.01 mm and less than or equal to 0.5 mm.

[0024] Under this design, not only can the first exhaust channel have a good exhaust effect, but also the size of the first exhaust channel can be prevented from being too large to cause external water vapor to erode the sealing ring, the sealing ring can be prevented from aging and losing function to cause the end cover assembly to leak liquid, the sealing property of the end cover assembly is ensured, and the service life of the energy storage device is improved.

[0025] The end cover assembly further comprises a sealing ring, the sealing ring is sleeved on the pole, is arranged in the first mounting hole, and is clamped between the pole and the hole wall surface of the first mounting hole in the radial direction of the pole, so that not only can short circuit caused by contact between the pole and the end cover be avoided, but also the gap between the pole and the end cover can be sealed, and the sealing reliability of the end cover assembly is ensured.

[0026] The end cover is further provided with a plurality of first limiting holes, the openings of the plurality of first limiting holes face the upper insulating piece, the plurality of first limiting holes are arranged around the first mounting hole and are arranged in a spaced manner with the first mounting hole;

[0027] The upper insulating piece is further provided with a plurality of second limiting holes, the plurality of second limiting holes penetrate the groove bottom wall surface and the surface of the upper insulating piece facing the end cover, are arranged around the second mounting hole, and are arranged in a spaced manner with the second mounting hole, and the second limiting holes and the first limiting holes are in one-to-one correspondence and are in communication;

[0028] The pressure ring is provided with a plurality of third limiting holes, the openings of the plurality of third limiting holes are located on the first surface, the plurality of third limiting holes are arranged around the third mounting hole and are arranged in a spaced manner with the third mounting hole, and the third limiting holes and the second limiting holes are in one-to-one correspondence and are in communication;

[0029] The end cover assembly further comprises a plurality of limiting columns, the limiting columns are respectively and one-to-one correspondingly arranged in the second limiting holes, one end of the limiting column is inserted into the corresponding first limiting hole, and the other end of the limiting column is inserted into the corresponding third limiting hole.

[0030] The design of the limiting column can not only increase the assembly stability of the end cover assembly, but also improve the torsional strength of the pole and the use reliability of the energy storage device.

[0031] The upper insulating piece is provided with a protrusion, which is arranged on the hole wall surface of the second limiting hole and abuts against the limiting column to realize interference assembly between the limiting column and the second limiting hole of the upper insulating piece and ensure the assembly stability between the limiting column and the upper insulating piece.

[0032] The protrusions are arranged at intervals around the second limiting hole to improve the assembly stability of the limiting column in the second limiting hole and avoid tilting of the limiting column.

[0033] The abutting distance between the protrusion and the limiting column in the thickness direction of the end cover assembly is greater than or equal to 0.1 mm and less than or equal to 0.7 mm.

[0034] The abutting distance between the first abutting surface and the limiting column is in a suitable range, which can not only avoid tilting or even falling of the limiting column due to too small abutting distance, but also avoid scratching of the limiting column against the upper insulating piece due to too large abutting distance and reduce the influence of plastic debris generated by scratching of the limiting column against the upper insulating piece on the sealing performance of the end cover assembly.

[0035] The interference amount between the protrusion and the limiting column is greater than or equal to 0.01 mm and less than or equal to 0.3 mm.

[0036] Due to size fluctuation in manufacturing of parts, the interference amount between the protrusion and the limiting column is in a suitable range, which can not only ensure that the limiting column will not fall from the second limiting hole due to too small interference amount, but also ensure that the limiting column will not scratch against the upper insulating piece due to too large interference amount and reduce the influence of plastic debris generated by scratching of the limiting column against the upper insulating piece on the sealing performance of the end cover assembly.

[0037] In a second aspect, the application provides an energy storage device, which comprises a shell, an electric core assembly and any of the above-mentioned end cover assemblies. The shell is provided with a receiving cavity and an opening. The receiving cavity is arranged on the inner side of the shell, and the opening is located on the top side of the receiving cavity and communicates with the receiving cavity. The electric core assembly is received in the receiving cavity, and the end cover assembly is mounted on the shell and seals the opening.

[0038] During the welding process of the compression ring and the pole column, the gas between the pole column and the compression ring will be expanded under the influence of high temperature. The expanded gas can be discharged to the external environment along the first exhaust channel and the second exhaust channel, and the gas will not be discharged from the molten weld, so as to avoid welding defects such as blowhole or pinhole at the welding position of the pole column and the compression ring, ensure the welding reliability between the pole column and the compression ring, and further ensure the assembly reliability of the end cover assembly. Moreover, since the distance between the second end and the first end is less than or equal to the length of the first exhaust channel, the channel path of the first exhaust channel can be prolonged. The first exhaust channel can not only discharge the welding gas, but also reduce the entry of external water vapor into the position of the pole column, avoid the water vapor from eroding the sealing ring and causing the sealing ring to fail, ensure the sealing reliability of the end cover assembly, and improve the service life of the energy storage device.

[0039] In addition, since the first exhaust channel and the second exhaust channel can pass the gas, temporary sealing caused by the close fit of the compression ring and the upper insulating piece and the close fit of the upper insulating piece and the end cover can be avoided. When the sealing ring fails, the end cover assembly can be detected in time through helium detection, so as to ensure the sealing reliability of the end cover assembly and avoid the problem of liquid leakage of the energy storage device.

[0040] In a third aspect, the present application provides a power utilization device, which comprises the energy storage device described above and supplies power to the power utilization device. BRIEF DESCRIPTION OF DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used by the embodiments of the present application will be described below.

[0042] Figure 1 is a structural schematic diagram of an energy storage device provided by the present application;

[0043] Figure 2 is Figure 1 is a structural schematic diagram of an end cover assembly in the energy storage device shown in FIG. 1;

[0044] Figure 3 is Figure 2 is a structural schematic diagram of the end cover assembly shown in FIG. 1 after being cut along A-A;

[0045] Figure 4 is Figure 2 is an exploded structural schematic diagram of the end cover assembly shown in FIG. 1 in a first implementation;

[0046] Figure 5 is Figure 4 is a structural schematic diagram of an end cover and a lower insulating piece in the end cover assembly shown in FIG. 1;

[0047] Figure 6 is Figure 4 is a structural schematic diagram of an upper insulating piece in the end cover assembly shown in FIG. 1;

[0048] Figure 7 is Figure 4 is a structural schematic view of the compression ring in the end cover assembly shown in FIG. 1 from another angle;

[0049] Figure 8 is Figure 4 is a structural schematic view of the assembly of the upper insulating member and the compression ring in the end cover assembly shown in FIG. 1;

[0050] Figure 9 is Figure 2 is a structural schematic view of the end cover assembly shown in FIG. 1 along the section line B-B;

[0051] Figure 10 is Figure 2 is an exploded structural schematic view of the end cover assembly shown in FIG. 1 in a second embodiment;

[0052] Figure 11 is Figure 10 is a structural schematic view of the compression ring in the end cover assembly shown in FIG. 1 from another angle.

[0053] The names corresponding to the respective reference numerals in the drawings are as follows:

[0054] energy storage device 100, housing 110, end cover assembly 120, end cover 10, lower insulating member 20, explosion-proof valve 30, protective sheet 40, upper insulating member 50, compression ring 60, pole 70, sealing ring 80, limiting column 90, third surface 101, fourth surface 102, explosion-proof hole 103, liquid inlet hole 104, first mounting hole 105, second mounting groove 106, first limiting hole 107, explosion-proof fence 21, liquid injection hole 201, fourth mounting hole 202, fifth surface 501, sixth surface 502, second mounting hole 503, first mounting groove 504, second limiting hole 505, first exhaust groove 506, groove bottom wall surface 507, groove side wall surface 508, first air inlet end 506a, first air outlet end 506b, first exhaust section 506c, second exhaust section 506d, intermediate section 506f, curved portion 506g, convex portion 51, convex point 52, first abutting surface 511, first guide surface 512, second abutting surface 521, second guide surface 522, third guide surface 523, first surface 601, second surface 602, circumferential surface 603, first exhaust passage 121, first end 121a, second end 121b, first section 121c, second section 121d, corner section 121f, curved portion 121g, second exhaust passage 122, third mounting hole 604, third limiting hole 605, second exhaust groove 606, second air inlet end 606a, second air outlet end 606b, third exhaust section 606c, fourth exhaust section 606d, connecting section 606f, and bent portion 606g. DETAILED DESCRIPTION

[0055] 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.

[0056] Please refer to Figure 1 , Figure 1 is a structural schematic diagram of the energy storage device 100 provided in the present application. In order to facilitate description, the width direction of the energy storage device 100 is defined as the X-axis direction, the length direction of the energy storage device 100 is defined as the Y-axis direction, and the height direction of the energy storage device 100 is defined as the Z-axis direction, and the X-axis direction, the Y-axis direction and the Z-axis direction are perpendicular to each other.

[0057] The present application provides an energy storage device 100, which 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 in the present application can be but is not limited to the listed products, and can also be other application forms. The present application does not strictly limit the application form of the energy storage device 100. The present application takes a square battery as an example for description.

[0058] The energy storage device 100 includes a shell 110, a battery cell assembly (not shown in the figure) and an end cover assembly 120. The shell 110 is provided with a receiving cavity (not shown in the figure) and an opening (not shown in the figure). The receiving cavity is arranged on the inner side of the shell 110 and contains electrolyte. The opening is located on the top side of the receiving cavity and communicates with the receiving cavity. The shell 110 can be made of aluminum, for example, the shell 110 can be an aluminum shell. The battery cell assembly is accommodated in the receiving cavity. The battery cell assembly can be soaked in the electrolyte. The end cover assembly 120 is mounted on the shell 110 and seals the opening, and is electrically connected with the battery cell assembly.

[0059] Please refer to Figures 2 to 4 , Figure 2 is a structural schematic diagram of the end cover assembly 120 in the energy storage device 100 shown in Figure 1 , Figure 3 is a structural schematic diagram of the end cover assembly 120 shown in Figure 2 cut along A-A, Figure 4 is an exploded structural schematic diagram of the end cover assembly 120 in the first embodiment shown in Figure 2 , Figure 2 and Figure 4 is not shown. The "cut along A-A" means cutting along the plane where the line A-A is located, and similar descriptions hereinafter can be understood in the same way.

[0060] The end cover assembly 120 comprises an end cover 10, a lower insulating piece 20, an explosion-proof valve 30, a protective sheet 40, an upper insulating piece 50, a compression ring 60, a pole 70, a sealing ring 80, and a limiting column 90. Along the thickness direction (the Z-axis direction shown in the figure) of the end cover 10, the lower insulating piece 20 is installed on one side of the end cover 10. The explosion-proof valve 30 and the protective sheet 40 are both installed on the end cover 10. Along the thickness direction of the end cover 10, the upper insulating piece 50 is installed on the other side of the end cover 10. Among them, the upper insulating piece 50 has two. Along the length direction (the X-axis direction shown in the figure) of the end cover 10, the two upper insulating pieces 50 are arranged at intervals. One upper insulating piece 50 serves as a positive electrode upper insulating piece, and the other upper insulating piece 50 serves as a negative electrode upper insulating piece. The compression ring 60 is installed on the upper insulating piece 50. Among them, the compression ring 60 has two. One compression ring 60 serves as a positive electrode compression ring and is installed on the positive electrode upper insulating piece. The other compression ring 60 serves as a negative electrode compression ring and is installed on the negative electrode upper insulating piece.

[0061] Along the thickness direction (the Z-axis direction shown in the figure) of the end cover assembly 120, the pole 70 penetrates through the end cover 10, the lower insulating piece 20, the upper insulating piece 50, and the compression ring 60, and is fixedly connected with the compression ring 60. Among them, the pole 70 has two. One pole 70 serves as a positive electrode pole and penetrates through the end cover 10, the lower insulating piece 20, the positive electrode upper insulating piece, and the positive electrode compression ring, and is fixedly connected with the positive electrode compression ring. The other pole 70 serves as a negative electrode pole and penetrates through the end cover 10, the lower insulating piece 20, the negative electrode upper insulating piece, and the negative electrode compression ring, and is fixedly connected with the negative electrode compression ring. The sealing ring 80 is sleeved on the pole 70 and clamped between the end cover 10 and the pole 70. Among them, the sealing ring 80 has two. One sealing ring 80 serves as a positive electrode sealing ring and is sleeved on the positive electrode pole and clamped between the end cover 10 and the positive electrode pole. The other sealing ring 80 serves as a negative electrode sealing ring and is sleeved on the negative electrode pole and clamped between the end cover 10 and the negative electrode pole.

[0062] Along the thickness direction of the end cover assembly 120, the limiting column 90 penetrates through the upper insulating piece 50 and abuts between the end cover 10 and the compression ring 60. Among them, the limiting column 90 has six. Three limiting columns 90 penetrate through the positive electrode insulating piece and abut between the end cover 10 and the positive electrode compression ring, and are arranged at intervals around the positive electrode pole. Three limiting columns 90 penetrate through the negative electrode insulating piece and abut between the end cover 10 and the negative electrode compression ring, and are arranged at intervals around the negative electrode pole.

[0063] Please refer to Figure 5 , Figure 5 is Figure 4 the structural schematic view of the end cover 10 and the lower insulating piece 20 in the end cover assembly 120 shown in FIG. 1.

[0064] The end cover 10 has a third surface 101 and a fourth surface 102. The third surface 101 and the fourth surface 102 are oppositely arranged along the thickness direction of the end cover 10. The end cover 10 is provided with an explosion-proof hole 103, a liquid inlet hole 104, a first mounting hole 105, a second mounting groove 106, and a first limiting hole 107. The explosion-proof hole 103, the liquid inlet hole 104, and the first mounting hole 105 all penetrate the end cover 10 along the thickness direction of the end cover 10. That is, the explosion-proof hole 103, the liquid inlet hole 104, and the first mounting hole 105 all penetrate the third surface 101 and the fourth surface 102. Along the length direction of the end cover 10, the explosion-proof hole 103 is located at the middle of the end cover 10, the liquid inlet hole 104 is located at one side of the explosion-proof hole 103 and is arranged in a spaced manner with the explosion-proof hole 103. Among them, the first mounting hole 105 has two. One first mounting hole 105 is located at the side of the liquid inlet hole 104 away from the explosion-proof hole 103 and is arranged in a spaced manner with the liquid inlet hole 104. The other second mounting hole is located at the side of the explosion-proof hole 103 away from the liquid inlet hole 104 and is arranged in a spaced manner with the explosion-proof hole 103.

[0065] The opening of the second mounting groove 106 is located at the third surface 101. The second mounting groove 106 is recessed from the third surface 101 to the fourth surface 102 (the negative direction of the Z axis shown in the figure), and is arranged around the first mounting hole 105 and communicates with the first mounting hole 105. Among them, the second mounting groove 106 has two. Along the length direction of the end cover 10, the two second mounting grooves 106 are arranged in a spaced manner. Each second mounting groove 106 is arranged around one first mounting hole 105 and communicates with one first mounting hole 105. For example, the second mounting groove 106 is a regular hexagon, and the second mounting groove 106 has six groove side wall surfaces (not labeled in the figure), and the six groove side wall surfaces are sequentially connected in a head-to-tail manner, and two groove side wall surfaces are parallel to the width direction of the end cover 10 (the Y axis direction shown in the figure).

[0066] The opening of the first limiting hole 107 faces the upper insulating piece 50 and is located at the groove bottom wall surface of the second mounting groove 106. The first limiting hole 107 is recessed from the groove bottom wall surface of the second mounting groove 106 to the fourth surface 102 (the negative direction of the Z axis shown in the figure), and is arranged in a spaced manner with the first mounting hole 105. Among them, the first limiting hole 107 has multiple, and a part of the first limiting hole 107 is arranged in a spaced manner around one first mounting hole 105, and another part of the first limiting hole 107 is arranged in a spaced manner around another first mounting hole 105. For example, the first limiting hole 107 has six, and every three first limiting holes 107 are uniformly arranged around one first mounting hole 105.

[0067] The lower insulating member 20 is located on the side of the fourth surface 102 away from the third surface 101. The lower insulating member 20 has an explosion-proof fence 21. The explosion-proof fence 21 is located in the middle of the lower insulating member 20 along the length direction (Y-axis direction shown in the figure) of the lower insulating member 20, and is arranged opposite to the explosion-proof hole 103. The lower insulating member 20 is provided with a liquid injection hole 201 and a fourth mounting hole 202. The liquid injection hole 201 and the fourth mounting hole 202 both penetrate the lower insulating member 20 along the thickness direction (Z-axis direction shown in the figure) of the lower insulating member 20. Along the length direction of the lower insulating member 20, the liquid injection hole 201 is located on one side of the explosion-proof fence 21 and is arranged apart from the explosion-proof fence 21, and is in communication with the liquid inlet hole 104. The electrolyte outside can enter the inside of the energy storage device 100 through the liquid inlet hole 104 and the liquid injection hole 201 in sequence to realize liquid injection of the energy storage device 100. Among them, the fourth mounting hole 202 has two. One fourth mounting hole 202 is located on the side of the liquid injection hole 201 away from the explosion-proof fence 21, and is arranged apart from the liquid injection hole 201, and is in communication with one first mounting hole 105. The other fourth mounting hole 202 is located on the side of the explosion-proof fence 21 away from the liquid injection hole 201, and is arranged apart from the explosion-proof fence 21, and is in communication with the other first mounting hole 105.

[0068] The explosion-proof valve 30 covers the opening of the explosion-proof hole 103 on the fourth surface 102. The protective sheet 40 covers the opening of the explosion-proof hole 103 on the third surface 101. When the gas pressure inside the energy storage device 100 is too large, the gas inside the energy storage device 100 can be discharged to the outside of the energy storage device 100 in time through the explosion-proof fence 21 and the explosion-proof hole 103 in sequence. The explosion-proof valve 30 will be broken under the action of the gas pressure, avoiding the explosion of the energy storage device 100, and improving the use reliability of the energy storage device 100.

[0069] Please see Figure 6 , Figure 6 is Figure 4 the structure diagram of the upper insulating member 50 in the end cover assembly 120 shown in the figure.

[0070] Each upper insulating member 50 is installed in one second mounting groove 106. For example, each upper insulating member 50 is a regular hexagon and is matched with one second mounting groove 106. Each upper insulating member 50 has a fifth surface 501 and a sixth surface 502. The fifth surface 501 is the surface of the upper insulating member 50 away from the end cover 10. Along the thickness direction (Z-axis direction shown in the figure) of the upper insulating member 50, the sixth surface 502 is arranged opposite to the fifth surface 501. That is, the sixth surface 502 is the surface of the upper insulating member 50 towards the end cover 10.

[0071] Each of the upper insulating pieces 50 is provided with a second mounting hole 503, a first mounting groove 504, a second limiting hole 505, and a first exhaust groove 506. The second mounting hole 503 penetrates the upper insulating piece 50 along the thickness direction of the upper insulating piece 50 and is in communication with the first mounting hole 105. That is, the second mounting hole 503 penetrates the fifth surface 501 and the sixth surface 502. The opening of the first mounting groove 504 is located on the fifth surface 501. The first mounting groove 504 is recessed from the fifth surface 501 to the sixth surface 502 (the negative direction of the Z axis in the figure). The first mounting groove 504 has a groove bottom wall surface 507 and a groove side wall surface 508. The groove bottom wall surface 507 is arranged opposite to the opening of the first mounting groove 504. The groove side wall surface 508 is arranged around the groove bottom wall surface 507 and is connected between the groove bottom wall surface 507 and the fifth surface 501. For example, the first mounting groove 504 is a regular hexagon, and the groove side wall surface 508 includes six third groove wall surfaces (not labeled in the figure), which are sequentially connected end to end, and two of the third groove wall surfaces are parallel to the width direction (the Y axis direction in the figure) of the end cover assembly 120.

[0072] The second limiting hole 505 penetrates the groove bottom wall surface 507 and the sixth surface 502 and is spaced apart from the second mounting hole 503 and the groove side wall surface 508 and is in communication with the first limiting hole 107. The second limiting hole 505 has a plurality of second limiting holes 505, which are arranged around the second mounting hole 503 at intervals and are in one-to-one correspondence with the plurality of first limiting holes 107. For example, the second limiting hole 505 has three second limiting holes 505, which are uniformly arranged around the second mounting hole 503 at intervals.

[0073] The opening of the first exhaust groove 506 is located on the groove bottom wall surface 507. The first exhaust groove 506 is recessed from the groove bottom wall surface 507 to the sixth surface 502 and is in communication with the second mounting hole 503 and is spaced apart from the second limiting hole 505. For example, the cross section of the first exhaust groove 506 is rectangular, triangular, or trapezoidal. Specifically, the first exhaust groove 506 has a plurality of first exhaust grooves 506, which are arranged around the second mounting hole 503 at intervals. For example, the first exhaust groove 506 has six first exhaust grooves 506, which are uniformly arranged around the second mounting hole 503 at intervals. The maximum groove width of the first exhaust groove 506 is greater than or equal to 0.01 mm and less than 5 mm, and the groove depth of the first exhaust groove 506 is greater than or equal to 0.01 mm and less than or equal to 0.5 mm. For example, the groove width of the first exhaust groove 506 can be 0.2 mm, and the groove depth of the first exhaust groove 506 can be 0.1 mm.

[0074] Each first exhaust groove 506 has a first air inlet end 506a and a first air outlet end 506b. The first air inlet end 506a is the end of the first exhaust groove 506 close to the second mounting hole 503 and communicates with the second mounting hole 503. The first air outlet end 506b is the end of the first exhaust groove 506 close to the groove side wall surface 508 and is arranged opposite to the first air inlet end 506a. The distance between the first air inlet end 506a and the first air outlet end 506b is less than the length of the first exhaust groove 506. In other words, the first exhaust groove 506 is not linear. In other embodiments, the distance between the first air inlet end 506a and the first air outlet end 506b can also be equal to the length of the first exhaust groove 506.

[0075] In the embodiment, the first exhaust groove 506 includes a first exhaust section 506c, a second exhaust section 506d and an intermediate section 506f. The first exhaust section 506c is the part of the first exhaust groove 506 close to the second mounting hole 503 and communicates with the second mounting hole 503 and includes the first air inlet end 506a. The first exhaust section 506c is linear. The second exhaust section 506d is the part of the first exhaust groove 506 close to the groove side wall surface 508 and is arranged apart from the first exhaust section 506c and includes the first air outlet end 506b. The second exhaust section 506d is linear. The intermediate section 506f is connected between the first exhaust section 506c and the second exhaust section 506d. The intermediate section 506f is not linear. The intermediate section 506f can include a plurality of curved sections 506g connected in sequence, and the bending directions of at least two curved sections 506g are opposite. For example, the intermediate section 506f includes two curved sections 506g, the curved sections 506g can be U-shaped, and the bending directions of the two curved sections 506g are opposite.

[0076] In addition, each upper insulating member 50 is also provided with a protrusion 51 and a protruding point 52. The protrusion 51 is arranged on the groove side wall surface 508 and protrudes from the groove side wall surface 508 to the direction of the second mounting hole 503 and is arranged apart from the first exhaust groove 506. For example, the protrusion 51 is strip-shaped, and the extension direction of the protrusion 51 is parallel to the thickness direction of the end cover assembly 120. The protrusion 51 has a plurality of protrusions 51 arranged apart around the groove bottom wall surface 507. For example, the protrusion 51 has twelve protrusions 51, and every two protrusions 51 are arranged on a third groove wall surface.

[0077] Each protrusion 51 has a first abutting surface 511 and a first guide surface 512. The first abutting surface 511 is the surface of the protrusion 51 away from the groove side wall surface 508. The first guide surface 512 is connected between the first abutting surface 511 and the fifth surface 501. In the direction from the fifth surface 501 to the sixth surface 502, the distance between the first guide surface 512 and the groove side wall surface 508 gradually increases. For example, the first guide surface 512 can be an inclined surface or an arc-shaped surface.

[0078] The convex points 52 are arranged on the hole wall surface of the second limiting hole 505 and protrude from the hole wall surface of the second limiting hole 505 to the central axis of the second limiting hole 505. There are multiple convex points 52. Each part of the convex points 52 is arranged on the hole wall surface of one second limiting hole 505 and is arranged at intervals around the second limiting hole 505 to ensure the assembly stability of the limiting column 90 in the second limiting hole 505 and avoid the inclination of the limiting column 90. For example, there are nine convex points 52, and every three convex points 52 are arranged on the hole wall surface of one second limiting hole 505 and are arranged at intervals around the central axis of the second limiting hole 505.

[0079] Each convex point 52 has a second abutting surface 521, a second guide surface 522, and a third guide surface 523. The second abutting surface 521 is the surface of the convex point 52 away from the hole wall surface of the second limiting hole 505. The second guide surface 522 is connected between the second abutting surface 521 and the groove bottom wall surface 507. In the direction of the groove bottom wall surface 507 to the sixth surface 502 (the negative direction of the Z axis shown in the figure), the distance between the second guide surface 522 and the hole wall surface of the second limiting hole gradually increases. For example, the second guide surface 522 can be an inclined surface or an arc surface. The third guide surface 523 is connected between the second abutting surface 521 and the sixth surface 502. In the direction of the sixth surface 502 to the groove bottom wall surface 507 (the positive direction of the Z axis shown in the figure), the distance between the third guide surface 523 and the hole wall surface of the second limiting hole gradually increases. For example, the third guide surface 523 can be an inclined surface or an arc surface. In some other embodiments, each convex point 52 can also have only the second guide surface 522 or the third guide surface 523, which is not specifically limited in the application.

[0080] Please refer to Figure 7 and Figure 8 , Figure 7 is Figure 4 the structural schematic view of the compression ring 60 in the end cover assembly 120 shown in FIG. 12 at another angle, Figure 8 is Figure 4 the assembly structure schematic view of the upper insulating piece 50 and the compression ring 60 in the end cover assembly 120 shown in FIG. 12.

[0081] Each compression ring 60 is installed in the first installation groove 504 of one upper insulating piece 50. For example, each compression ring 60 is a regular hexagon and is matched with the first installation groove 504 of one upper insulating piece 50. Each compression ring 60 has a first surface 601, a second surface 602 and a peripheral side surface 603. The first surface 601 is the surface of the compression ring 60 facing the groove bottom wall surface 507. Specifically, the first surface 601 and the first exhaust groove 506 form the first exhaust passage 121. For example, the cross section of the first exhaust passage 121 is rectangular, triangular or trapezoidal. There are a plurality of first exhaust passages 121, which are arranged around the second installation hole 503 at intervals to increase the exhaust rate of the welding gas when the compression ring 60 is welded with the pole 70 and improve the welding efficiency of the compression ring 60 and the pole 70. For example, there are six first exhaust passages 121, which are evenly arranged around the second installation hole 503.

[0082] It should be noted that, since the opening of the first exhaust groove 506 is located on the groove bottom wall surface 507, the groove wall surface of the first exhaust groove 506 can form the first exhaust passage 121 with the first surface 601. The design of the first exhaust groove 506 can increase the cross-sectional area of the first exhaust passage 121, which helps to increase the exhaust rate of the welding gas when the compression ring 60 is welded with the pole 70 and improve the welding rate of the compression ring 60 and the pole 70.

[0083] In the design, the maximum width of the first exhaust passage 121 is greater than or equal to 0.01 mm and less than 5 mm, and the depth of the first exhaust passage 121 is greater than or equal to 0.01 mm and less than or equal to 0.5 mm. For example, the width of the first exhaust passage 121 can be 0.2 mm, and the depth of the first exhaust passage 121 can be 0.1 mm. In this design, not only can the first exhaust passage 121 have a good exhaust effect, but also can avoid the size of the first exhaust passage 121 being too large to cause the water vapor from the outside to erode the sealing ring 80, avoid the sealing ring 80 aging and losing function to cause the end cover assembly 120 to leak liquid, ensure the sealing of the end cover assembly 120 and improve the service life of the energy storage device.

[0084] Each first exhaust passage 121 has a first end 121a and a second end 121b. The first end 121a is an end of the first exhaust passage 121 close to the second mounting hole 503, and communicates with the second mounting hole 503. The first end 121a is enclosed by the first air inlet end 506a and the first surface 601. The second end 121b is an end of the first exhaust passage 121 close to the groove side wall surface 508, and is arranged opposite to the first end 121a and spaced apart from the convex portion 51. The second end 121b is enclosed by the first air outlet end 506b and the first surface 601. The distance between the first end 121a and the second end 121b is less than the length of the first exhaust passage 121. In other words, the first exhaust passage 121 is non-linear. In other embodiments, the distance between the first end 121a and the second end 121b can be equal to the length of the first exhaust passage 121.

[0085] In the present embodiment, the first exhaust passage 121 includes a first section 121c, a second section 121d, and a corner section 121f. The first section 121c is a portion of the first exhaust passage 121 close to the second mounting hole 503, and includes the first end 121a and communicates with the second mounting hole 503. The first section 121c is enclosed by the first exhaust section 506c and the first surface 601, and is linear. The second section 121d is a portion of the first exhaust passage 121 close to the groove side wall surface 508, and is arranged spaced apart from the first section 121c and includes the second end 121b. The second section 121d is enclosed by the second exhaust section 506d and the first surface 601, and is linear. The corner section 121f is connected between the first section 121c and the second section 121d. The corner section 121f is enclosed by the intermediate section 506f and the first surface 601, and is non-linear. The corner section 121f can include a plurality of curved portions 121g connected in sequence, and the bending directions of at least two curved portions 121g are opposite. For example, the corner section 121f includes two curved portions 121g, and the curved portions 121g are U-shaped, and the bending directions of the two curved portions 121g are opposite. Each curved portion 121g is enclosed by a curved section 506g and the first surface 601.

[0086] The second surface 602 is arranged opposite to the first surface 601 along the thickness direction (the Z-axis direction in the drawings) of the pressure ring 60. That is, the second surface 602 is a surface of the pressure ring 60 facing away from the groove bottom wall surface 507. The peripheral surface 603 is connected between the first surface 601 and the second surface 602, and is arranged spaced apart from the groove side wall surface 508.

[0087] In the embodiment, the protrusion 51 of the upper insulating member 50 abuts against the circumferential side surface 603 of the compression ring 60 to form the second exhaust passage 122 between the groove side surface 508 and the circumferential side surface 603, and the second exhaust passage 122 communicates the first exhaust passage 121 and the external environment. Specifically, the first abutting surface 511 of the protrusion 51 abuts against the circumferential side surface 603 of the compression ring 60. The second exhaust passage 122 communicates the second end 121b and the second section 121d.

[0088] The protrusion 51 not only realizes the interference assembly between the compression ring 60 and the first mounting groove 504 of the upper insulating member 50, but also ensures the assembly stability between the compression ring 60 and the upper insulating member 50. In addition, the protrusion 51 can ensure that the circumferential side surface 603 of the compression ring 60 is spaced apart from the groove side surface 508 of the first mounting groove 504, so that the second exhaust passage 122 can be formed between the circumferential side surface 603 and the groove side surface 508. In the assembly process of the compression ring 60 and the upper insulating member 50, the first guide surface 512 of the protrusion 51 can guide the compression ring 60 to be mounted in the first mounting groove 504, which helps to improve the assembly efficiency and assembly reliability of the compression ring 60 and the upper insulating member 50. In addition, in the assembly process of the end cover assembly 120, the upper insulating member 50 can be assembled with the compression ring 60 first, and then assembled in the second mounting groove 106 of the end cover 10, so as to save the assembly time of the end cover assembly 120 and improve the assembly efficiency of the end cover assembly 120.

[0089] In other embodiments, the upper insulating member 50 can also not be provided with the protrusion 51, and the compression ring 60 is provided with a protrusion (not shown in the figure). The protrusion is arranged on the circumferential side surface 603 of the compression ring 60 and abuts against the groove side surface 508 of the upper insulating member 50 to form the second exhaust passage 122 between the circumferential side surface 603 and the groove side surface 508. In this case, the structure of the protrusion in the compression ring 60 can refer to the related description of the protrusion 51 in the upper insulating member 50 above, and will not be described here again.

[0090] Each compression ring 60 is provided with a third mounting hole 604 and a third limiting hole 605. The third mounting hole 604 is located in the middle of the compression ring 60 and penetrates the compression ring 60 along the thickness direction of the compression ring 60. That is, the third mounting hole 604 penetrates the first surface 601 and the second surface 602 and is spaced apart from the circumferential side surface 603. Specifically, the third mounting hole 604 communicates the second mounting hole 503 and the first exhaust passage 121. The third mounting hole 604 communicates the first end 121a and the first section 121c.

[0091] The opening of the third limiting hole 605 is located on the first surface 601. The third limiting hole 605 is recessed from the first surface 601 to the second surface 602, and is arranged in a spaced manner with the third mounting hole 604. Among them, the third limiting hole 605 is multiple, and the multiple third limiting holes 605 are arranged in a spaced manner around the third mounting hole 604, and are in one-to-one correspondence with the multiple second limiting holes 505. For example, the third mounting hole 604 has six, and the six third mounting holes 604 are arranged in a uniformly spaced manner around the third mounting hole 604.

[0092] Each pole column 70 is arranged through a fourth mounting hole 202 of the lower insulating piece 20, a first mounting hole 105 of the end cover 10, a second mounting hole 503 of an upper insulating piece 50, and a third mounting hole 604 of a compression ring 60, and is fixedly connected with the hole wall surface of the third mounting hole 604 of the compression ring 60. Among them, each pole column 70 is welded and fixed with the hole wall surface of the third mounting hole 604 of the compression ring 60.

[0093] During the welding process of the compression ring 60 and the pole column 70, the gas between the pole column 70 and the compression ring 60 will expand under the influence of high temperature. The expanded gas can be discharged to the external environment along the first exhaust channel 121 and the second exhaust channel 122, and the gas will not be discharged from the molten state of the welding bead, which can avoid the welding defects such as blowhole or pinhole at the welding position of the pole column 70 and the compression ring 60, ensure the welding reliability between the pole column 70 and the compression ring, and further ensure the assembly reliability of the end cover assembly 120. Moreover, due to the non-linear design of the first exhaust channel 121, the channel path of the first exhaust channel 121 can be lengthened, which not only can provide the welding gas to be discharged, but also can reduce the external water vapor entering the position of the pole column 70, avoid the water vapor eroding the sealing ring 80 to cause the sealing ring 80 to fail, ensure the sealing reliability of the end cover assembly 120, and improve the service life of the energy storage device 100. Furthermore, the bending directions of the at least two bending parts 121g in the corner section 121f are opposite, which can increase the obstacle for the external water vapor to enter the position of the pole column 70, avoid the water vapor eroding the sealing ring 80 to cause the sealing ring 80 to fail, ensure the sealing reliability of the end cover assembly 120, and improve the service life of the energy storage device 100.

[0094] In addition, since the first exhaust channel 121 and the second exhaust channel 122 can be used for gas to pass through, the temporary sealing caused by the close fit of the compression ring 60 and the upper insulating piece 50, and the upper insulating piece 50 and the end cover 10 can be avoided. When the sealing ring 80 fails, the end cover assembly 120 can be detected in time through helium detection, which ensures the sealing reliability of the end cover assembly 120 and avoids the problem of liquid leakage of the energy storage device 100.

[0095] Each sealing ring 80 is sleeved on one pole column 70 and arranged in a fourth mounting hole 202 of the lower insulating member 20 and a first mounting hole 105 of the end cover 10, and clamped between the circumferential surface of the pole column 70 and the hole wall surface of the first mounting hole 105 in the radial direction of the pole column 70, which not only avoids the short circuit caused by the contact between the pole column 70 and the end cover 10, but also seals the gap between the pole column 70 and the end cover 10, thereby ensuring the sealing reliability of the end cover assembly 120.

[0096] In the assembly process of the end cover assembly 120, the fourth mounting hole 202 of the lower plastic and the first mounting hole 105 of the end cover 10 can be aligned first, then the upper insulating member 50 assembled with the compression ring 60 is installed in the second mounting groove 106 of the end cover 10, and the pole column 70 sleeved with the sealing ring 80 is sequentially inserted through the fourth mounting hole 202 of the lower plastic, the first mounting hole 105 of the end cover 10, the second mounting hole 503 of the upper insulating member 50 and the third mounting hole 604 of the compression ring 60, and pressure is applied to the pole column 70 to extrude the sealing ring 80, so that the sealing ring 80 is clamped between the pole column 70 and the hole wall of the first mounting hole 105, and finally the compression ring 60 and the pole column 70 are welded together.

[0097] Please refer to Figure 9 , Figure 9 is Figure 2 the structure schematic view of the end cover assembly 120 shown in FIG. 6 along the section B-B.

[0098] The limiting columns 90 are respectively and correspondingly inserted into the second limiting holes 505 of the upper insulating member 50, one end of the limiting column 90 is inserted into the corresponding first limiting hole 107, and the other end is inserted into the corresponding third limiting hole 605. For example, the limiting column 90 can be a ceramic column made of ceramic. The design of the limiting column 90 not only can increase the assembly stability of the end cover assembly 120, but also can improve the torsional strength of the pole column 70 and the use reliability of the energy storage device 100. It should be understood that the number of the limiting column 90 is not limited to Figure 4 six as shown in the figure, and the limiting column 90 can be less than five or more than seven, which is not specifically limited in the present application.

[0099] In this embodiment, the protrusion 52 of the upper insulating member 50 abuts against the circumferential surface of the limiting post 90 to realize interference assembly between the limiting post 90 and the second limiting hole 505 of the upper insulating member 50, thereby ensuring assembly stability between the limiting post 90 and the upper insulating member 50. The interference amount between the protrusion 52 and the limiting post 90 is greater than or equal to 0.01 mm and less than or equal to 0.3 mm. For example, the interference amount between the protrusion 52 and the limiting post 90 is 0.1 mm. It should be noted that due to dimensional fluctuations in component manufacturing, the interference amount between the protrusion 52 and the limiting post 90 is within a suitable range, which not only ensures that the limiting post 90 will not fall out of the second limiting hole 505 due to too small interference amount, but also ensures that the limiting post 90 will not scratch the upper insulating member 50 due to too large interference amount, thereby reducing the impact of plastic debris generated by the scratching of the limiting post 90 and the upper insulating member 50 on the sealing performance of the end cover assembly 120.

[0100] Specifically, the second abutting surface 521 of the protrusion 52 abuts against the circumferential surface of the limiting post 90. The abutting distance H between the second abutting surface 521 and the limiting post 90 along the thickness direction of the upper insulating member 50 is greater than or equal to 0.1 mm and less than or equal to 0.7 mm. For example, the abutting distance H between the second abutting surface 521 and the limiting post 90 along the thickness direction of the upper insulating member 50 is 0.3 mm. The abutting distance H between the second abutting surface 521 and the limiting post 90 is within a suitable range, which not only avoids the risk of tilting or even falling out of the limiting post 90 due to too small abutting distance, but also avoids scratching of the limiting post 90 and the upper insulating member 50 due to too large abutting distance, thereby reducing the impact of plastic debris generated by the scratching of the limiting post 90 and the upper insulating member 50 on the sealing performance of the end cover assembly 120. Moreover, the second guide surface 522 and the third guide surface 523 of the protrusion 52 can guide the limiting post 90 to be arranged in the second limiting hole 505 during assembly of the limiting post 90 and the upper insulating member 50, thereby helping to improve assembly efficiency and assembly reliability of the limiting post 90 and the upper insulating member 50.

[0101] Please refer to Figures 10 to 11 , Figure 10 is Figure 2 the exploded structural schematic view of the end cover assembly 120 in the second embodiment, Figure 11 is Figure 10 the structural schematic view of the compression ring 60 in the end cover assembly 120 from another angle.

[0102] The end cover assembly 120 shown in the embodiment is different from the end cover assembly 120 shown in the first embodiment in that the upper insulating member 50 is not provided with the first exhaust groove 506, and the compression ring 60 is provided with the second exhaust groove 606. The opening of the second exhaust groove 606 is located on the first surface 601. The second exhaust groove 606 is recessed from the first surface 601 to the second surface 602, and is in communication with the third mounting hole 604 and is arranged in a spaced manner with the third limiting hole 605. For example, the cross section of the second exhaust groove 606 is rectangular, triangular or trapezoidal. Specifically, the second exhaust groove 606 has a plurality of second exhaust grooves 606, which are arranged in a spaced manner around the third mounting hole 604. For example, the second exhaust groove 606 has six second exhaust grooves 606, which are arranged in a uniformly spaced manner around the third mounting hole 604. The groove width of the second exhaust groove 606 is greater than or equal to 0.01 mm and less than 5 mm, and the groove depth of the second exhaust groove 606 is greater than or equal to 0.01 mm and less than or equal to 0.5 mm. For example, the groove width of the second exhaust groove 606 can be 0.2 mm, and the groove depth of the second exhaust groove 606 can be 0.1 mm.

[0103] Each second exhaust groove 606 has a second air inlet end 606a and a second air outlet end 606b. The second air inlet end 606a is the end of the second exhaust groove 606 close to the third mounting hole 604, and is in communication with the third mounting hole 604. The second air outlet end 606b is the end of the second exhaust groove 606 close to the peripheral side surface 603, and is arranged in a spaced manner with the second air inlet end 606a. The distance between the second air inlet end 606a and the second air outlet end 606b is less than the length of the second exhaust groove 606. In other words, the second exhaust groove 606 is not straight.

[0104] The second exhaust groove 606 includes a third exhaust section 606c, a fourth exhaust section 606d and a connecting section 606f. The third exhaust section 606c is the part of the second exhaust groove 606 close to the third mounting hole 604, and is in communication with the third mounting hole 604 and includes the second air inlet end 606a. The third exhaust section 606c is straight. The fourth exhaust section 606d is the part of the second exhaust groove 606 close to the peripheral side surface 603, and is arranged in a spaced manner with the third exhaust section 606c and includes the second air outlet end 606b. The fourth exhaust section 606d is straight. The connecting section 606f is connected between the third exhaust section 606c and the fourth exhaust section 606d. The connecting section 606f is not straight, for example, the connecting section 606f can include a plurality of bending sections 606g, the plurality of bending sections 606g are connected in sequence, and the bending directions of at least two bending sections 606g are opposite. For example, the connecting section 606f includes two bending sections 606g, the bending section 606g is U-shaped, and the bending directions of the two bending sections 606g are opposite.

[0105] In this embodiment, the second exhaust groove 606 and the groove bottom wall surface 507 of the upper insulating member 50 form the first exhaust passage 121. Specifically, the second exhaust end 606a and the groove bottom wall surface 507 form the first end 121a of the first exhaust passage 121. The second exhaust end 606b and the groove bottom wall surface 507 form the second end 121b. The third exhaust section 606c and the groove bottom wall surface 507 form the first section 121c. The fourth exhaust section 606d and the groove bottom wall surface 507 form the second section 121d. The connecting section 606f and the groove bottom wall surface 507 form the corner section 121f. Each bending portion 606g and the groove bottom wall surface 507 form a bending portion 121g. In other embodiments, the upper insulating member 50 can be provided with the first exhaust groove 506, and the compression ring 60 can be provided with the second exhaust groove 606. The first exhaust groove 506 and the second exhaust groove 606 form the first exhaust passage 121, which is not limited in the present application.

[0106] During the welding of the compression ring 60 and the pole 70, the gas between the pole 70 and the compression ring 60 will expand under high temperature. The expanded gas can be discharged to the outside environment along the first exhaust passage 121 and the second exhaust passage 122, and the gas will not be discharged from the molten weld, which can avoid welding defects such as blowhole or pinhole at the welding position of the pole 70 and the compression ring 60, ensure the welding reliability between the pole 70 and the compression ring, and further ensure the assembly reliability of the end cover assembly 120. Moreover, due to the non-linear design of the first exhaust passage 121, the path of the first exhaust passage 121 can be extended, and the first exhaust passage 121 can not only discharge the welding gas, but also reduce the entry of external water vapor into the position of the pole 70, avoid the water vapor from eroding the sealing ring 80 and causing the sealing ring 80 to fail, ensure the sealing reliability of the end cover assembly 120, and improve the service life of the energy storage device 100.

[0107] In addition, since the first exhaust passage 121 and the second exhaust passage 122 can pass the gas, temporary sealing caused by the close contact between the compression ring 60 and the upper insulating member 50, and the close contact between the upper insulating member 50 and the end cover 10 can be avoided. When the sealing ring 80 fails, the end cover assembly 120 can be detected in time by helium detection, which ensures the sealing reliability of the end cover assembly 120 and avoids the problem of liquid leakage of the energy storage device 100.

[0108] The present application also provides an electric device, which includes the above-mentioned energy storage device 100, and the energy storage device 100 supplies power to the electric device. The electric device can be a new energy vehicle, a power storage station, a server, and other devices that need power.

[0109] The above description is only specific embodiments of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present application, which should be covered in the protection scope of the present application; in the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An end cap assembly for an energy storage device, characterized in that, Includes end caps, upper insulators, pressure rings, and pole posts; The end cap is provided with a first mounting hole, which penetrates the end cap along the thickness direction. Along the thickness direction of the end cap, the upper insulating member is installed on one side of the end cap. The upper insulating member has a second mounting hole and a first mounting groove. The second mounting hole penetrates the upper insulating member along the thickness direction and communicates with the first mounting hole. The opening of the first mounting groove is located on the surface of the upper insulating member opposite to the end cap. The first mounting groove surrounds the second mounting hole and communicates with the second mounting hole. The first mounting groove has a bottom wall and a side wall. The bottom wall is opposite to the opening of the first mounting groove. The side wall is connected to the bottom wall and surrounds the bottom wall. The pressure ring is installed in the first mounting groove. The pressure ring has a first surface, a second surface, and a peripheral side surface. The first surface faces the bottom wall of the groove, the second surface is disposed opposite to the first surface, and the peripheral side surface is connected between the first surface and the second surface. The pressure ring is provided with a third mounting hole, which penetrates the first surface and the second surface and communicates with the second mounting hole; The upper insulating member and the pressure ring cooperate to form a first exhaust channel in one of three ways, with one of the following three ways being present: In the first way, the upper insulating member also has a first exhaust groove, the opening of which is located on the bottom wall of the groove, and the first exhaust groove communicates with the second mounting hole, forming the first exhaust channel by the first exhaust groove and the first surface; In the second way, the pressure ring has a second exhaust groove, the opening of which is located on the first surface, and the second exhaust groove communicates with the third mounting hole, forming the first exhaust channel by the second exhaust groove and the bottom wall of the groove; In the third way, the upper insulating member also has a first exhaust groove, the opening of which is located on the bottom wall of the groove, and the first exhaust groove communicates with the second mounting hole; the pressure ring also has a second exhaust groove, the opening of which is located on the first surface, and the second exhaust groove communicates with the third mounting hole, forming the first exhaust channel by the second exhaust groove and the first exhaust groove. The first exhaust channel includes a first end and a second end. The first end is connected to both the second mounting hole and the third mounting hole. The second end is disposed opposite to the first end. The distance between the second end and the first end is less than or equal to the length of the first exhaust channel. The upper insulating member and the pressure ring cooperate to form a second exhaust channel in one of two ways, and one of the following two ways may be present: In the first way, the upper insulating member has a protrusion, which is located on the side wall of the groove and abuts against the peripheral side, so as to form a second exhaust channel between the side wall of the groove and the peripheral side; In the second way, the pressure ring has a protrusion, which is located on the peripheral side and abuts against the side wall of the groove, so as to form a second exhaust channel between the peripheral side and the side wall of the groove. The second exhaust passage connects the second end to the external environment; The pole is inserted through the first mounting hole, the second mounting hole and the third mounting hole, and is welded and fixed to the wall of the third mounting hole.

2. The end cap assembly according to claim 1, characterized in that, There are multiple first exhaust channels, which are arranged at intervals around the third mounting hole.

3. The end cap assembly according to claim 1 or 2, characterized in that, The first exhaust passage includes a first section, a corner section, and a second section. The first section is connected to both the second mounting hole and the third mounting hole, and includes the first end. The second section is connected to the second exhaust passage, includes the second end, and is spaced apart from the first section. The corner section is connected between the first section and the second section.

4. The end cap assembly according to claim 3, characterized in that, The corner segment includes multiple curved sections, which are connected in sequence, with at least two curved sections bending in opposite directions.

5. The end cap assembly according to claim 1, characterized in that, The maximum width of the first exhaust channel is greater than or equal to 0.01 mm and less than or equal to 5 mm; and / or, the depth of the first exhaust channel is greater than or equal to 0.01 mm and less than or equal to 0.5 mm.

6. The end cap assembly according to claim 1, characterized in that, The end cap assembly further includes a sealing ring, which is sleeved on the pole post and disposed in the first mounting hole, and is held radially between the pole post and the hole wall of the first mounting hole.

7. The end cap assembly according to claim 1, characterized in that, The end cap is also provided with a plurality of first limiting holes, the openings of the plurality of first limiting holes facing the upper insulating member, the plurality of first limiting holes being arranged around the first mounting hole and spaced apart from the first mounting hole; The upper insulating component is also provided with a plurality of second limiting holes, which penetrate the bottom wall of the groove and the surface of the upper insulating component facing the end cap, and are arranged around the third mounting hole and spaced apart from the third mounting hole. The second limiting holes correspond one-to-one with the first limiting holes and are connected. The pressure ring is provided with a plurality of third limiting holes, the openings of the plurality of third limiting holes are located on the first surface, the plurality of third limiting holes are arranged around the third mounting hole and are spaced apart from the third mounting hole, and the third limiting holes are connected to the second limiting holes one by one; The end cap assembly also includes a plurality of limiting posts, each of which is respectively inserted through the second limiting hole. One end of each limiting post is inserted into the corresponding first limiting hole, and the other end is inserted into the corresponding third limiting hole.

8. The end cap assembly according to claim 7, characterized in that, The upper insulating member is provided with a protrusion, which is located on the wall surface of the second limiting hole and abuts against the limiting post.

9. The end cap assembly according to claim 8, characterized in that, There are multiple protrusions, which are arranged at intervals around the second limiting hole.

10. The end cap assembly according to claim 8 or 9, characterized in that, Along the thickness direction of the end cap assembly, the abutment distance between the protrusion and the limiting post is greater than or equal to 0.1 mm and less than or equal to 0.7 mm.

11. The end cap assembly according to claim 8 or 9, characterized in that, The interference between the protrusion and the limiting post is greater than or equal to 0.01 mm and less than or equal to 0.3 mm.

12. An energy storage device, characterized in that, The device includes a housing, a battery cell assembly, and an end cap assembly as described in any one of claims 1 to 11. The housing has a receiving cavity and an opening. The receiving cavity is located inside the housing, and the opening is located on the top side of the receiving cavity and communicates with the receiving cavity. The battery cell assembly is received in the receiving cavity, and the end cap assembly is mounted on the housing and closes the opening.

13. An electrical appliance, characterized in that, It includes the energy storage device as described in claim 12, wherein the energy storage device supplies power to the electrical equipment.

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