Top cover assembly, energy storage device and energy storage system

Abstract

The invention discloses a top cover assembly, an energy storage device and an energy storage system. The top cover assembly comprises a top cover plate, lower plastic, a pole, upper plastic, a pressing ring and a limiting structure. The top cover plate is provided with a first through hole, the lower plastic is connected to the top cover plate and provided with a second through hole corresponding to the first through hole, and the first through hole is communicated with the second through hole. The pole penetrates through the first through hole and the second through hole. The upper plastic is arranged on the periphery of the pole and penetrates through the first through hole and the second through hole, and the upper plastic is connected to the top cover plate. The pressing ring is arranged in the first mounting groove and is connected to the pole; a gap is formed between the pressing ring and the groove wall surface of the first mounting groove; and the limiting structure is configured to limit the axial rotation of the pressing ring along the first through hole relative to the first mounting groove.

Description

Technical Field

[0001] The present application relates to the field of energy storage technology, and in particular to a top cover assembly, an energy storage device and an energy storage system. Background Art

[0002] In the related art, a top cover assembly of an energy storage device (eg, a battery) is generally used to seal the battery cell, thereby preventing the electrolyte inside the battery from leaking out, so as to ensure the normal use of the battery.

[0003] When the existing top cover assembly's pressure ring is welded to the pole, the heat on the pressure ring may be transferred to the lower plastic installed with it, causing the lower plastic to melt. This may damage the lower plastic structure, affect the normal installation of the pressure ring, and be detrimental to the sealing effect between the lower plastic and the pole and the pressure ring, causing electrolyte leakage and affecting the normal use of the battery. Summary of the invention

[0004] The embodiments of the present application disclose a top cover assembly, an energy storage device and an energy storage system, which are used to improve the situation where the installation effect of the pressure ring is poor due to the hot melting of the lower plastic.

[0005] In order to achieve the above objectives, in a first aspect, the present application discloses a top cover assembly, comprising:

[0006] A top cover plate, wherein the top cover plate is provided with a first through hole;

[0007] A lower plastic, the lower plastic is connected to the top cover plate, a second through hole is formed in the lower plastic corresponding to the first through hole, and the second through hole is connected to the first through hole, a first mounting groove is formed on a surface of the lower plastic facing away from the top cover plate, and the first mounting groove is arranged around the outer periphery of the second through hole;

[0008] A pole, wherein the pole is passed through the first through hole and the second through hole;

[0009] An upper plastic, the upper plastic is arranged on the outer periphery of the pole and penetrates the first through hole and the second through hole, and the upper plastic is connected to the top cover plate;

[0010] A pressure ring, the pressure ring is arranged in the first installation groove, the pressure ring is connected to the pole, and an outer peripheral surface of the pressure ring forms a gap with a groove wall surface of the first installation groove; and

[0011] A limiting structure is configured to limit the rotation of the pressure ring relative to the first mounting groove around the axial direction of the first through hole.

[0012] In the top cover assembly disclosed in the present application, a pressure ring is installed in the first mounting groove of the lower plastic, and the pressure ring is connected to the bottom surface of the groove of the first mounting groove, and a distance is formed between the pressure ring and the groove wall of the first mounting groove. When the pressure ring is welded, the heat can be blocked from being transferred from the pressure ring to the groove wall of the first mounting groove by the distance, thereby reducing or avoiding the situation where the lower plastic is locally melted due to the welding of the pressure ring. On this basis, considering that after the spacing is formed between the pressure ring and the groove wall of the first mounting groove, the groove wall of the first mounting groove is difficult to provide torque to the pressure ring, and the pressure ring may be twisted in the first mounting groove. Based on this, the present application also sets a limiting structure, and uses the limiting structure to limit the rotation of the pressure ring in the axial direction of the first through hole in the first mounting groove, thereby preventing the pressure ring from twisting in the first mounting groove, and effectively ensuring the connection reliability between the pressure ring and the pole and the lower plastic.

[0013] As an optional implementation, the limiting structure is formed within the spacing.

[0014] When the limiting structure is arranged within the spacing, if the pressure ring is twisted relative to the first installation groove at the spacing, the limiting structure can directly stop the pressure ring, making it difficult for the pressure ring to rotate at the spacing. In this way, the pressure ring can be prevented from rotating in the first installation groove.

[0015] On the other hand, when the pressure ring is heated during welding, even if the heat on the pressure ring reaches the gap, it will be directly transferred to the limiting structure. The limiting structure will melt after being heated, and the melted limiting structure can fill the gap. While maintaining the limiting structure on the pressure ring, it can also reduce or even prevent the heat on the pressure ring from being transferred to the lower plastic, thereby reducing the effect of the heat on the pressure ring on the lower plastic.

[0016] As an optional implementation, the limiting structure is provided on the pressure ring, and / or the limiting structure is provided on the first mounting groove.

[0017] When the limiting structure is arranged at the pressure ring and / or the first installation groove, the limiting structure can be engaged with the groove wall surface of the first installation groove, or the limiting structure can be engaged with the outer peripheral surface of the pressure ring, or the two limiting structures can be engaged with each other. In this way, the pressure ring can be limited in the first installation groove, which is conducive to preventing the pressure ring from rotating in the first installation groove.

[0018] As an optional embodiment, the outer circumferential surface of the pressure ring is configured as a non-circular surface, the limiting structure is protruding from the bottom surface of the first mounting groove, and the limiting structure is close to or abuts against the outer circumferential surface of the pressure ring to limit the axial rotation of the pressure ring relative to the first mounting groove around the first through hole.

[0019] When the outer circumference of the pressure ring is a non-circumferential surface, the limiting structure is in contact with the outer circumferential surface of the pressure ring, so that the limiting structure generates torque on the outer circumferential surface of the pressure ring, thereby limiting the rotation of the pressure ring in the first installation groove. In addition, the limiting structure is arranged within the spacing, and the structure is simple. The limiting structure is mainly limited by the torque generated by the pressure ring with a non-circumferential outer surface and the limiting structure, thereby reducing the space occupied by the first installation groove. That is, while realizing the effective limiting of the pressure ring, the limiting structure can also reduce the space occupied by the first installation groove, which is convenient for the installation of the pressure ring.

[0020] As an optional implementation, the limiting structure is arranged around the outer circumference of the pressure ring, or,

[0021] The outer circumference of the pressure ring has a plurality of corners, and the limiting structure includes a plurality of limiting parts, which are arranged at intervals along the outer circumference of the pressure ring, and each of the limiting parts is arranged corresponding to each of the corners.

[0022] When the limiting structure is completely wrapped around the outer circumference of the pressure ring, the torque between the limiting structure and the outer circumference of the pressure ring can be increased to limit the torsion of the pressure ring, thereby improving the limiting effect of the pressure ring. When the pressure ring is a polygon such as a square or a pentagon, each limiting part is set corresponding to each corner position, so that the limiting part can be wrapped around the outer circumference of the corner to provide the corner with torque during rotation, thereby limiting the rotation of the pressure ring. In other words, when the pressure ring has corners, the limiting part can be set only at the corners of the pressure ring, which can not only achieve the same limitation of the pressure ring, but also the limiting position is accurate.

[0023] As an optional embodiment, the limiting structure has an end face along the axial direction of the first through hole, the end face extends to connect with the bottom surface of the first mounting groove to form a first step surface, the outer peripheral surface of the pressure ring is formed with a second step surface, and the first step surface is matched and connected with the second step surface.

[0024] When the first step surface forms a mating connection with the second step surface, the first step surface can provide torque for the second step surface when rotating, thereby preventing the pressure ring from rotating in the first mounting groove. For example, when the first step surface and the second step surface are matingly connected at any position on the outer circumference of the pressure ring, the first step surface and the second step surface can both generate torque, that is, when the limiting structure and the pressure ring are connected in a limited manner by using the step surface mating method, the limiting structure can limit the rotation of the pressure ring when it is set at any position within the spacing or when it is set on the outer circumference of the pressure ring in a whole circle, and has good limiting reliability.

[0025] As an optional implementation, the outer circumferential surface of the pressure ring is provided with a groove, the inner wall surface of the groove is constructed as the second step surface, and the limiting structure is at least partially located in the groove so that the first step surface is close to or abuts against the second step surface.

[0026] A second step portion is formed by the inner wall surface of the groove. When the limiting structure extends into the groove, the inner wall surface of the groove can be adapted to the shape of the first step surface. When the pressure ring is connected to the limiting structure, the first step surface and the second step surface are easy to cooperate, thereby limiting the rotation of the pressure ring and effectively preventing the twisting of the pressure ring.

[0027] As an optional implementation, along the radial direction of the first through hole, a side of the limiting structure away from the outer circumferential surface of the pressure ring is spaced apart from a groove wall surface of the first mounting groove.

[0028] When the limiting structure is set within the spacing, the limiting structure abuts against the pressing ring to limit the rotation of the pressing ring, and the limiting structure is set at a distance from the groove wall of the first installation groove, so most of the heat of the pressing ring can only be transferred to the limiting structure, and it is difficult to be transferred to the groove wall of the first installation groove through the limiting structure. In this way, the influence of the heat of the pressing ring on the lower plastic can be reduced, and the structure of the lower plastic can be prevented from being damaged due to hot melting.

[0029] As an optional implementation, along the radial direction of the first through hole, a side of the limiting structure away from the outer circumferential surface of the pressure ring is connected to a groove wall surface of the first mounting groove.

[0030] When the limiting structure is a boss, the boss is connected to the groove wall surface of the first installation groove along the radial direction of the first through hole, so that the limiting structure fills the gap. For example, if the limiting structure adopts a heat-insulating material, when the limiting structure fills the gap, the limiting structure can form a thermal barrier between the groove wall surface of the first installation groove and the outer peripheral surface of the pressure ring, which is conducive to reducing the heat transfer of the pressure ring to the lower plastic, and preventing the structure of the lower plastic from being damaged due to hot melting.

[0031] As an optional implementation, the limiting structure includes a convex portion and a concave portion, one of the pressure ring and the first mounting groove is provided with the convex portion, and the other is provided with the concave portion, and the convex portion is snap-connected to the concave portion.

[0032] The present application uses the concave-convex fitting of the limiting structure, and when the pressure ring rotates around the axial direction of the first through hole, the convex part abuts against the inner wall surface of the concave part, thereby limiting the rotation of the pressure ring. Moreover, the connection is made by the concave-convex fitting method, and this structure is simple and is conducive to being set in a relatively narrow spacing space. It can be seen that the limiting structure of the concave-convex fitting can not only achieve effective limiting of the pressure ring, but also save space in the first installation groove to facilitate the installation of the pressure ring.

[0033] As an optional embodiment, the pressure ring is provided with the convex portion, the side wall surface of the first mounting groove is provided with two convex portions, the two convex portions are spaced apart to form the concave portion, and the outer peripheral surface of the convex portion and / or the convex portion is configured as an arc surface.

[0034] When the first installation groove is provided with two protrusions, a protrusion is provided on the outer peripheral surface of the pressure ring, the protrusion extends into the recess, and the outer peripheral surfaces of the two protrusions are in contact with the outer peripheral surfaces of the protrusions. When the outer peripheral surfaces of the two protrusions are both arc surfaces, the protrusion slides between the two protrusions along the guidance of the arc surface, which is conducive to the limited installation of the pressure ring in the first installation groove. On the other hand, when the two protrusions are limitedly connected with the protrusion on the pressure ring, the arc surfaces on the two protrusions form a line contact with the arc surfaces on the protrusions. Compared with the surface-to-surface contact method, the contact area of ​​the line contact is smaller, which can effectively reduce the heat transfer between the pressure ring and the limiting structure, which is conducive to improving the hot melting of the lower plastic.

[0035] As an optional implementation, the limiting structure protrudes from the bottom surface of the first mounting groove along the axial direction of the first through hole, the thickness of the limiting structure is d1, and the thickness of the pressure ring is d2, wherein d1<d2.

[0036] Taking the example of a limiting structure made of the same plastic material as the lower plastic, when the heat of the pressure ring is transferred to the limiting structure, the limiting structure may be hot-melted. If the thickness d1 of the limiting structure is greater than the thickness d2 of the pressure ring, the limiting structure is exposed to the spacing along the direction of the first through hole. If the limiting structure is hot-melted, the melted limiting structure may flow to the surface of the pressure ring or the lower surface of the lower plastic, resulting in material loss of the limiting structure, making it difficult to limit the pressure ring within the spacing. In other words, when d1 is less than d2, the limiting structure is hot-melted within the spacing, which can prevent the limiting structure from flowing out of the spacing after hot-melting, which is beneficial for the limiting structure to maintain its limiting effect on the pressure ring within the spacing.

[0037] As an optional implementation, a second mounting groove is provided on a side of the top cover plate facing the lower plastic, and the second mounting groove is arranged around the outer periphery of the first through hole;

[0038] The top cover assembly also includes a sealing member, which is sleeved on the outer periphery of the upper plastic and located in the second mounting groove. Along the axial direction of the first through hole, the sealing member is connected between the pressure ring and the top cover plate.

[0039] Considering the sealing installation between the pressure ring and the pole and the lower plastic to prevent the outflow of the electrolyte in the energy storage device, the present application is provided with a sealing member, and a sealing ring is used to achieve an effective sealing installation between the pressure ring and the pole and the lower plastic.

[0040] As an optional implementation, the limiting structure is provided in the first mounting groove and protrudes from the bottom surface of the first mounting groove, the sealing member is connected between the pressure ring and the top cover plate, the pressure ring compresses the sealing member, and the compression amount of the sealing member along the axial direction of the first through hole is d3, and the thickness of the limiting structure is d1, wherein d1>d3;

[0041] The thickness of the sealing member is D1, and the thickness of the sealing member after being compressed is D2, wherein D1-D2=d3.

[0042] When the pressure ring is installed, the seal can be compressed by the pressure ring. If the thickness of the limiting structure is greater than the compressed thickness of the seal, the pressure ring can form a connection with the limiting structure. On the contrary, if the thickness of the limiting structure is less than the compressed thickness of the seal, after the seal is compressed, the thickness of the seal is still large, which pushes up the pressure ring, making it difficult for the pressure ring to form a limiting connection with the limiting structure. In other words, when the thickness of the limiting structure is greater than the compressed thickness of the seal, it is conducive to the pressure ring and the limiting structure to form a limiting connection, preventing the limiting structure from failing.

[0043] As an optional implementation, the upper plastic is snap-fitted with at least one of the top cover plate, the pole, and the pressure ring.

[0044] Taking into account that the pressure ring may be twisted and may drive the pole to rotate, in order to further improve the anti-torsion effect of the pressure ring and even the pole, the present application arranges the upper plastic to be clamped with the top cover plate, the pole, and the pressure ring, so as to use the upper plastic to form a limit for the pole and the pressure ring, thereby preventing the rotation of the pressure ring and the pole.

[0045] As an optional implementation, when the upper plastic is snap-fitted with the top cover plate, the pole, and the pressure ring, a first snap-fitting portion is provided on a side of the upper plastic adjacent to the pole, and a first matching portion is provided on the pole corresponding to the first snap-fitting portion, and one of the first snap-fitting portion and the first matching portion is a first protrusion, and the other is a first depression;

[0046] A second clamping portion is provided on one side of the upper plastic adjacent to the top cover plate, and a second matching portion is provided on the top cover plate corresponding to the second clamping portion, wherein one of the second clamping portion and the second matching portion is a second protrusion, and the other is a second depression;

[0047] A third clamping portion is provided on one side of the upper plastic adjacent to the pressing ring, and a third matching portion is provided on the pressing ring corresponding to the third clamping portion. One of the third clamping portion and the third matching portion is a third protrusion, and the other is a third depression.

[0048] The fitting connection between the upper plastic and the top cover plate, the pole and the pressure ring is connected through its own structure. When the upper plastic and the top cover plate, the pole and the pressure ring are installed, they can naturally form a lock, thereby achieving effective locking between the upper plastic and the top cover plate, the pole and the pressure ring without occupying additional installation space of the top cover assembly.

[0049] As an optional implementation, the upper plastic has a first side and a second side along the axial direction of the first through hole, the first clamping portion is arranged on the first side, the second clamping portion and the third clamping portion are both arranged on the second side, and along the axial direction of the first through hole, the second clamping portion and the third clamping portion are staggered.

[0050] Since the second clamping part and the third clamping part are arranged on the same side, in order to avoid the clamping interference between the second clamping part, the second matching part and the third clamping part, the third matching part. When the second clamping part and the third clamping part are arranged on the upper plastic correspondingly, the two are staggered, which is conducive to preventing the second clamping part from affecting the installation of the third clamping part and the third matching part, or preventing the third clamping part from affecting the installation of the second clamping part and the second matching part. In addition, when the second clamping part and the third clamping part are staggered, it is conducive to the alignment installation of the upper plastic with the top cover plate and the pressure ring, which is convenient for the positioning installation of the upper plastic.

[0051] As an optional embodiment, the top cover assembly also includes a sealing member, and when the third clamping portion is a third protrusion, the sealing member is located between the third clamping portion and the side wall of the second through hole along the axial direction of the first through hole, the thickness of the sealing member is D1, and the thickness of the third clamping portion is d4, wherein D1<d4.

[0052] After being compressed, the seal can move in the space formed by the pressure ring, the third clamping part and the groove wall of the second mounting groove. Since the thickness of the third clamping part is relatively large, the movable space on one side of the seal is blocked. The groove wall of the second mounting groove is also above the groove wall of the first mounting groove, which blocks the movable space on the other side of the seal. The top of the seal is blocked by the pressure ring. In this way, the movable space of the seal during deformation is limited, which is beneficial to reduce the risk of the seal jumping out of the second mounting groove when being compressed by the pressure ring, and is beneficial to improving the sealing effect of the seal.

[0053] In a second aspect, the present application further discloses an energy storage device, comprising:

[0054] case;

[0055] A battery cell, wherein the battery cell is disposed in the housing; and

[0056] According to the top cover assembly of the first aspect, the top cover assembly is configured to cover the shell.

[0057] When the top cover assembly disclosed in the first aspect is arranged on the energy storage device, the outer peripheral surface of the pressure ring of the top cover assembly is spaced from the groove wall surface of the first mounting groove of the lower plastic, which is conducive to reducing the hot melting of the lower plastic and preventing the structure of the lower plastic from being affected, resulting in a decrease in the sealing performance of the top cover assembly, which causes the electrolyte in the energy storage device to flow out. Moreover, a limiting structure is provided within the spacing between the outer peripheral surface of the pressure ring and the groove wall surface of the first mounting groove to limit the pressure ring from twisting at the spacing, so as to prevent the pressure ring from twisting and causing the sealing effect between the pressure ring and the lower plastic and the pole to deteriorate, thereby preventing the electrolyte from flowing out. In addition, in order to prevent the twisting of the pressure ring from driving the rotation of the pole, the present application also designs a clamping structure for the upper plastic to further prevent the pressure ring and the pole from twisting and causing the sealing effect of the top cover assembly to deteriorate.

[0058] In a third aspect, the present application further discloses an energy storage system, comprising the energy storage device described in the second aspect.

[0059] In the energy storage system, the top cover assembly of the energy storage device can improve the hot melting of the lower plastic by setting the distance between the pressure ring and the lower plastic, and prevent the twisting of the pressure ring and the pole through the limiting structure and the clamping design of the upper plastic, thereby improving the leakage (electrolyte) problem of the energy storage device that may be caused by the twisting of the pressure ring and the pole.

[0060] Compared with the prior art, the beneficial effects of this application are:

[0061] The present application discloses a top cover assembly, an energy storage device and an energy storage system. Among them, the top cover assembly includes a top cover plate, a lower plastic, a pole, an upper plastic, a pressure ring and a limiting structure. The top cover plate is provided with a first through hole, the lower plastic is connected to the top cover plate and a second through hole is provided corresponding to the first through hole, and the first through hole is connected to the second through hole. The pole is penetrated by the first through hole and the second through hole. The upper plastic is arranged on the periphery of the pole and penetrated by the first through hole and the second through hole, and the upper plastic is connected to the top cover plate. The pressure ring is arranged in the first mounting groove and connected to the pole, and a spacing is formed between the pressure ring and the groove wall of the first mounting groove. The limiting structure is configured to limit the axial rotation of the pressure ring relative to the first mounting groove along the first through hole. The top cover assembly disclosed in the present application reduces the heat transfer to the lower plastic during the welding of the pressure ring by setting a spacing between the pressure ring and the groove wall of the first mounting groove, thereby alleviating the situation where the lower plastic undergoes hot melting. In addition, setting a distance between the pressure ring and the groove wall of the first installation groove may cause the pressure ring to twist. In this regard, a limiting structure is provided to limit the rotation of the pressure ring to avoid the pressure ring from twisting. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0063] Figure 1 A schematic diagram of the structure of the top cover assembly disclosed in the embodiment of the present application;

[0064] Figure 2 Another structural schematic diagram of the top cover assembly disclosed in the embodiment of the present application;

[0065] Figure 3 An exploded schematic diagram of a top cover assembly disclosed in an embodiment of the present application;

[0066] Figure 4 for Figure 2 Schematic diagram of the first structure at AA in the middle;

[0067] Figure 5 This is a schematic diagram of the first structure of the limiting structure disclosed in the embodiment of the present application;

[0068] Figure 6 A second structural schematic diagram of the limiting structure disclosed in the embodiment of the present application;

[0069] Figure 7 A third structural schematic diagram of the limiting structure disclosed in the embodiment of the present application;

[0070] Figure 8 for Figure 2 Schematic diagram of the second structure at AA in the middle;

[0071] Fig. 9 This is a schematic diagram of the fourth structure of the limiting structure disclosed in the embodiment of the present application;

[0072] Fig.10 for Figure 2 Schematic diagram of the third structure at AA in the middle;

[0073] Fig.11 for Figure 2 Schematic diagram of the fourth structure at AA in the middle;

[0074] Fig.12 Another exploded schematic diagram of the top cover assembly disclosed in the embodiment of the present application;

[0075] Fig.13 This is a schematic diagram of the structure of the upper plastic disclosed in the embodiment of the present application;

[0076] Fig.14A schematic diagram of the structure of the energy storage device disclosed in the embodiment of the present application;

[0077] Fig.15 A schematic diagram of an energy storage system disclosed in an embodiment of the present application.

[0078] Description of reference numerals:

[0079] 101. Top cover assembly; 1. Top cover plate; 11. First through hole; 12. Second mounting groove; 13. Second matching part; 2. Lower plastic; 21. Second through hole; 22. First mounting groove; 22a. Groove wall of first mounting groove; 22b. Groove bottom of first mounting groove; 22c. Spacing; 3. Upper plastic; 31. First clamping part; 32. Second clamping part; 33. Third clamping part; 3a. First side; 3b. Second side; 4. Pole; 41. First matching part; 5. Pressing ring; 5a. Outer peripheral surface of pressing ring; 51. Corner; 5b. Second step surface; 52. Groove; 53. Third matching part; 6. Limiting structure; 61. Protrusion; 62. Concave; 62a. Protrusion; 6a. End surface; 6b. First step surface; 63. Limiting part; 7. Sealing member;

[0080] 100. Energy storage device; 102. Housing;

[0081] 200, energy storage system; 201, electric energy conversion device; 202, first user load; 203, second user load. DETAILED DESCRIPTION

[0082] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0083] In this application, the terms "upper", "lower", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0084] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0085] In addition, the terms "installed", "set", "provided with", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0086] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0087] In the related art, the top cover assembly of an energy storage device (such as a battery cell or a battery pack composed of multiple battery cells) can usually be used to seal the battery cells in the energy storage device, thereby preventing the electrolyte inside from leaking out to ensure the normal use of the energy storage device.

[0088] Normally, when installing the pole, the pressure ring in the top cover assembly needs to be welded to the pole to achieve the installation of the pole. During the welding process, the pressure ring is heated, and the heat on the pressure ring may be transferred to the lower plastic installed with it, causing the lower plastic to melt due to the heat of the pressure ring. In this way, the physical properties of the lower plastic may be deteriorated, and even the lower plastic may be damaged, which is not conducive to the normal installation of the pressure ring and the pole, affecting the sealing effect of the lower plastic, the pressure ring and the pole bracket, and affecting the normal use of the energy storage device.

[0089] In this regard, the present application discloses a top cover assembly, an energy storage device, and an energy storage system. In the top cover assembly, a first mounting groove is provided on the lower plastic, a pressure ring is provided in the first mounting groove, and a distance is provided between the pressure ring and the groove wall of the first mounting groove. When the pressure ring generates heat during welding, the distance between the pressure ring and the groove wall of the first mounting groove can reduce the heat transfer from the pressure ring to the lower plastic, thereby alleviating the situation where the lower plastic melts. In this way, it is possible to avoid the situation where the pressure ring is twisted due to the heat melting of the lower plastic, which weakens the installation effect of the lower plastic on the pressure ring.

[0090] Considering that after setting a distance between the pressure ring and the groove wall of the first installation groove, the connection between the outer circumference of the pressure ring and the groove wall of the first installation groove is weakened, and the torque provided by the groove wall of the first installation groove to the outer circumference of the pressure ring is weakened, when the pressure ring may rotate due to external force, it is difficult for the lower plastic to limit the rotation of the pressure ring. In this regard, the present application sets a limit structure to limit the rotation of the pressure ring in the first installation groove.

[0091] The technical solution of the present application will be further described below in conjunction with embodiments and drawings.

[0092] First, please refer to Figures 1 to 4 The present application discloses a top cover assembly 101, including a top cover plate 1, a lower plastic 2, an upper plastic 3, a pole 4, a pressure ring 5 and a limiting structure 6. The top cover plate 1 is provided with a first through hole 11, the lower plastic 2 is connected to the top cover plate 1, and the lower plastic 2 is provided with a second through hole 21 corresponding to the first through hole 11, and the second through hole 21 is connected to the first through hole 11. The lower plastic 2 is provided with a first mounting groove 22 on a side facing away from the top cover plate 1, and the first mounting groove 22 is arranged around the outer periphery of the second through hole 21. The pole 4 is penetrated through the first through hole 11 and the second through hole 21. The upper plastic 3 is arranged on the outer periphery of the pole 4 and penetrates through the first through hole 11 and the second through hole 21, and the upper plastic 3 is connected to the top cover plate 1. The pressure ring 5 is arranged in the first mounting groove 22, the pressure ring 5 is connected to the pole 4, and the outer peripheral surface 5a of the pressure ring forms a spacing 22c with the groove wall surface 22a of the first mounting groove. The limiting structure 6 is configured to limit the rotation of the pressing ring 5 relative to the first mounting groove 22 around the axial direction of the first through hole 11 .

[0093] In the top cover assembly 101 disclosed in the present application, a pressure ring 5 is installed in the first mounting groove 22 of the lower plastic 2, and the pressure ring 5 is connected to the groove bottom surface 22b of the first mounting groove, and a spacing 22c is formed between the pressure ring 5 and the groove wall surface 22a of the first mounting groove. When the pressure ring 5 is welded, the heat can be blocked from being transferred from the pressure ring 5 to the groove wall surface 22a of the first mounting groove by the spacing 22c, thereby reducing the situation where the pressure ring 5 causes the lower plastic 2 (the groove wall surface 22a of the first mounting groove) to melt. Moreover, considering that after the spacing 22c is formed between the pressure ring 5 and the groove wall surface 22a of the first mounting groove, the groove wall surface 22a of the first mounting groove is difficult to provide torque to the pressure ring 5, and the pressure ring 5 may be twisted in the first mounting groove 22. In this regard, the present application sets a limiting structure 6 to limit the rotation of the pressure ring 5 in the first mounting groove 22 around the axial direction of the first through hole 11, thereby preventing the pressure ring 5 from twisting in the first mounting groove 22.

[0094] It should be noted that in Figure 1 In the example shown, the direction indicated by X is the axial direction of the first through hole 11 , and the direction indicated by Y may be the radial direction of the first through hole 11 .

[0095] In some embodiments, the limiting structure 6 is formed in the interval 22c between the outer peripheral surface 5a of the pressure ring and the groove wall surface 22a of the first installation groove. When the limiting structure 6 is arranged in the interval 22c, if the pressure ring 5 is twisted relative to the first installation groove 22 at the interval 22c, the limiting structure 6 can stop the pressure ring 5, making it difficult for the pressure ring 5 to rotate at the interval 22c. In this way, the rotation of the pressure ring 5 in the first installation groove 22 can be avoided.

[0096] On the other hand, when the pressure ring 5 is heated during welding, the heat on the pressure ring 5 is transferred to the limiting structure 6. The limiting structure 6 is melted after being heated. The melted limiting structure 6 can be filled into the spacing 22c. While maintaining the limiting function of the limiting structure 6 on the pressure ring 5, it can also prevent the heat on the pressure ring 5 from being transferred to the lower plastic 2, thereby reducing the effect of the heat on the pressure ring 5 on the hot melting of the lower plastic 2.

[0097] It is understandable that the limiting structure 6 can be integrally formed with the lower plastic 2 or the pressure ring 5 during production, or the limiting structure 6 can also be a separate component and is separately arranged within the spacing 22c.

[0098] Optionally, the limiting structure 6 may be made of plastic or heat-insulating material, etc., wherein the heat-insulating material may be glass fiber, asbestos, etc., which is not specifically limited in the present application.

[0099] Optionally, the limiting structure 6 can be configured as a convex strip, a convex block, etc. protruding from the bottom surface 22b of the first installation groove.

[0100] See also Figure 4 In some embodiments, the limiting structure 6 protrudes from the bottom surface 22b of the first mounting groove along the axial direction of the first through hole 11, the thickness of the limiting structure 6 is d1, and the thickness of the pressure ring 5 is d2, wherein d1<d2.

[0101] Take the example of the limiting structure 6 using the same plastic material as the lower plastic 2. If the thickness d1 of the limiting structure 6 is greater than the thickness d2 of the pressure ring 5, the limiting structure 6 is exposed to the spacing 22c along the direction of the first through hole 11. When the heat of the pressure ring 5 is transferred to the limiting structure 6, the limiting structure 6 is hot-melted, and the melted limiting structure 6 may flow to the surface of the pressure ring 5 or the lower surface of the lower plastic 2, which may not only affect the surface flatness of the pressure ring 5 and the lower plastic 2, but also cause the loss of material of the limiting structure 6, making it difficult to limit the pressure ring 5 within the spacing 22c. In other words, when d1 is less than d2, the limiting structure 6 is hot-melted within the spacing 22c, which can prevent the limiting structure 6 after hot-melt from flowing out of the spacing 22c, which is conducive to the limiting structure 6 maintaining the limiting effect on the pressure ring 5 within the spacing 22c.

[0102] Optionally, the limiting structure 6 is disposed on the pressing ring 5 , and / or the limiting structure 6 is disposed in the first mounting groove 22 .

[0103] In the first example, when the limiting structure 6 is provided on the pressing ring 5 , the limiting structure 6 on the pressing ring 5 can be engaged with the groove wall surface 22 a of the first installation groove, thereby realizing the limiting of the pressing ring 5 in the first installation groove 22 .

[0104] In the second example, when the limiting structure 6 is disposed in the first installation groove 22 , the limiting structure 6 in the first installation groove 22 can be engaged with the outer peripheral surface 5 a of the pressure ring, thereby achieving the limiting of the pressure ring 5 in the first installation groove 22 .

[0105] In the third example, a limiting structure 6 is provided in both the pressure ring 5 and the first mounting groove 22 , and the first limiting structure 6 on the pressure ring 5 is mutually engaged with the limiting structure 6 at the first mounting groove 22 , thereby achieving the limiting of the pressure ring 5 in the first mounting groove 22 .

[0106] When the limiting structure 6 is arranged at the pressing ring 5 and / or the first installation groove 22, the limiting structure 6 can be engaged with the groove wall surface 22a of the first installation groove, or the limiting structure 6 is engaged with the outer peripheral surface 5a of the pressing ring, or two limiting structures 6 are engaged with each other. In this way, the pressing ring 5 can be limited in the first installation groove 22, which is conducive to preventing the pressing ring 5 from rotating in the first installation groove 22.

[0107] See also Figure 5 Optionally, the limiting structure 6 includes a convex portion 61 and a concave portion 62 , one of the pressing ring 5 and the first mounting groove 22 is provided with the convex portion 61 , and the other is provided with the concave portion 62 , and the convex portion 61 is snap-connected to the concave portion 62 .

[0108] In some examples, the outer peripheral surface 5a of the pressure ring is provided with a protrusion 61, the groove wall surface 22a of the first installation groove or the groove bottom surface 22b of the first installation groove is provided with a recess 62, and the protrusion 61 on the pressure ring 5 is snap-fitted into the recess 62 of the first installation groove 22.

[0109] In other examples, the outer peripheral surface 5a of the pressure ring is provided with a recess 62, the groove wall surface 22a of the first mounting groove or the groove wall surface 22a of the first mounting groove is provided with a protrusion 61, and the protrusion 61 of the first mounting groove 22 is snap-fitted into the recess 62 of the pressure ring 5.

[0110] The present application realizes the clamping by the concave-convex matching of the limiting structure 6. When the pressing ring 5 rotates in the axial direction around the first through hole 11, the convex part 61 abuts against the inner wall surface of the concave part 62, thereby limiting the rotation of the pressing ring 5. Moreover, the connection is made by the concave-convex matching, which is simple in structure and is conducive to being set in a relatively narrow spacing 22c space. In this way, the limiting structure 6 with concave-convex matching can not only realize the effective limiting of the pressing ring 5, but also save the space of the first installation groove 22, so as to facilitate the installation of the pressing ring 5.

[0111] Optionally, the groove wall surface 22a of the first installation groove is provided with two protrusions 62a, and the two protrusions 62a are arranged at an interval to form a recess 62, and the outer peripheral surface of the protrusion 62a and / or the convex portion 61 is configured as an arc surface.

[0112] In an exemplary embodiment, when the first mounting groove 22 is provided with two protrusions 62a, a protrusion 61 is provided on the outer peripheral surface 5a of the pressing ring, and the protrusion 61 extends into the recess 62, and the outer peripheral surfaces of the two protrusions 62a abut against the outer peripheral surface of the protrusion 61. When the outer peripheral surfaces of the two protrusions 62a are both arc surfaces, the protrusion 61 slides between the two protrusions 62a along the guidance of the arc surface, thereby facilitating the limited installation of the pressing ring 5 in the first mounting groove 22. On the other hand, when the two protrusions 62a are limitedly connected with the protrusion 61 on the pressing ring 5, the arc surfaces on the two protrusions 62a form a line contact with the arc surfaces on the protrusion 61. Compared with the surface-to-surface contact method, the contact area of ​​the line contact is smaller, which can effectively reduce the heat transfer between the pressing ring 5 and the limiting structure 6, and is conducive to improving the hot melting of the lower plastic 2.

[0113] In other embodiments, the groove wall surface 22a of the first installation groove is provided with a protrusion 62a, and the protrusion 62a is recessed to adapt to the shape of the protrusion 61 on the pressing ring 5 to form a recess 62. In this way, it is conducive to realizing the limited installation of the first installation groove 22 and the pressing ring 5.

[0114] It can be understood that the outer circumferential surface 5a of the pressure ring can be a circular surface or a non-circular surface, wherein the non-circular surface can include, for example, an elliptical outer circumferential surface and a polygonal outer circumferential surface.

[0115] See also Figure 6 In some embodiments, when the outer circumferential surface 5a of the pressure ring is configured as a non-circumferential surface, the limiting structure 6 is protrudingly arranged on the groove bottom surface 22b of the first installation groove, and the limiting structure 6 is close to or abuts against the outer circumferential surface 5a of the pressure ring to limit the axial rotation of the pressure ring 5 around the first through hole 11. In other words, when the outer circumferential surface 5a of the pressure ring is a non-circumferential surface, the limiting structure 6 abuts against the outer circumferential surface 5a of the pressure ring, so that the limiting structure 6 generates torque on the outer circumferential surface 5a of the pressure ring, thereby limiting the rotation of the pressure ring 5 in the first installation groove 22. Moreover, the limiting structure 6 is arranged within the spacing 22c, and the structure is simple. It is mainly limited by the torque generated between the pressure ring 5 with a non-circumferential outer surface and the limiting structure 6, thereby reducing the space occupied by the first installation groove 22. That is, while realizing the effective limiting of the pressure ring 5, the limiting structure 6 can also reduce the space occupied by the first installation groove 22, which is convenient for the installation of the pressure ring 5.

[0116] Optionally, the limiting structure 6 is arranged around the outer peripheral surface 5a of the pressing ring. In other words, the limiting structure 6 is completely wrapped around the outer peripheral surface 5a of the pressing ring, thereby increasing the torque between the limiting structure 6 and the outer peripheral surface 5a of the pressing ring to limit the torsion of the pressing ring 5, thereby improving the limiting effect of the pressing ring 5.

[0117] See also Figure 7In some embodiments, the outer peripheral surface 5a of the pressure ring has a plurality of corners 51, and the limiting structure 6 includes a plurality of limiting portions 63, and the plurality of limiting portions 63 are arranged at intervals along the outer peripheral surface 5a of the pressure ring, and each limiting portion 63 is arranged corresponding to each corner 51. Exemplarily, when the pressure ring 5 is a polygon such as a square or a pentagon, each limiting portion 63 is arranged corresponding to each corner 51, and the limiting portion 63 is coated on the outer peripheral surface of the corner 51 to provide a torque to the corner 51 during rotation, so as to limit the rotation of the pressure ring 5. In other words, when the pressure ring 5 has corners 51, the limiting portion 63 can be arranged only at the corners 51 of the pressure ring 5, which can not only realize the limitation of the pressure ring 5, but also help to reduce the setting of the limiting structure 6, reduce the space occupied by the first mounting groove 22, and facilitate the installation of the pressure ring 5.

[0118] See also Figure 8 and Fig. 9 In some embodiments, the limiting structure 6 has an end face 6a along the axial direction of the first through hole 11, the end face 6a extends to connect with the bottom surface 22b of the first mounting groove to form a first step face 6b, and the outer peripheral surface 5a of the pressure ring is formed with a second step face 5b, and the first step face 6b is matched with the second step face 5b. That is to say, when the first step face 6b is matched with the second step face 5b, the first step face 6b can provide torque for the second step face 5b when rotating to prevent the pressure ring 5 from rotating in the first mounting groove 22. Exemplarily, when the first step face 6b is matched with the second step face 5b at any position of the outer peripheral surface 5a of the pressure ring, the first step face 6b and the second step face 5b can generate torque, that is, when the limiting structure 6 is connected with the pressure ring 5 by the step face matching method, the limiting structure 6 can limit the rotation of the pressure ring 5 when it is set at any position within the spacing 22c or when the outer peripheral surface 5a of the pressure ring is set in a full circle, and has good limiting reliability.

[0119] Optionally, the outer peripheral surface 5a of the pressure ring is provided with a groove 52, the inner wall surface of the groove 52 is configured as a second step surface 5b, and the limiting structure 6 is at least partially located in the groove 52, so that the first step surface 6b is close to or abuts against the second step surface 5b. Exemplarily, the limiting structure 6 extends into the groove 52, and the inner wall surface of the groove 52 forms a second step portion, so that the inner wall surface of the groove 52 is adapted to the shape of the first step surface 6b, and when the pressure ring 5 is connected to the limiting structure 6, it is convenient for the first step surface 6b to cooperate with the second step surface 5b, thereby limiting the rotation of the pressure ring 5 to prevent the pressure ring 5 from twisting.

[0120] Optionally, the plurality of limiting portions 63 of the limiting structure 6 all have an end face 6a along the axial direction of the first through hole 11, and the end face 6a of each limiting portion 63 forms a plurality of first step faces 6b with the groove bottom face 22b of the first mounting groove, and each first step face 6b can be matched and connected with the second step face 5b. Exemplarily, when the plurality of limiting portions 63 of the limiting structure 6 are arranged at each corner 51 of the pressure ring 5, the limiting portion 63 can not only limit the rotation of the pressure ring 5 by abutting against the outer peripheral surface 5a of the pressure ring, but also can form a first step face 6b to match and connect with the second step face 5b of the pressure ring 5, so as to enhance the limiting effect on the pressure ring 5.

[0121] Optionally, the limiting structure 6 can be a plurality of limiting parts 63 connected in sequence around the outer circumference of the pressure ring 5, so that the limiting structure 6 is arranged around the outer circumference 5a of the pressure ring in a full circle. Moreover, while the limiting structure 6 is arranged around the outer circumference of the pressure ring 5 in a full circle, it can also form an integral first step surface 6b with the groove bottom surface 22b of the first mounting groove. It is understandable that when the limiting structure 6 is arranged around the outer circumference 5a of the pressure ring in a full circle, the first step surface 6b and the second step surface 5b are also matched and connected around the outer circumference 5a of the pressure ring in a full circle to limit the rotation of the pressure ring 5. The first step surface 6b arranged in a full circle has a better limiting effect, which is conducive to improving the effect of limiting the rotation of the pressure ring 5.

[0122] Optionally, the limiting structure 6 may be a plurality of protrusions or protrusions arranged at intervals around the outer circumference 5a of the pressing ring, or may be a full circle of protrusions arranged around the outer circumference 5a of the pressing ring.

[0123] See also Figure 8 In some embodiments, along the radial direction of the first through hole 11, the side of the limiting structure 6 that is away from the outer peripheral surface 5a of the pressure ring is spaced from the groove wall surface 22a of the first installation groove. It can be understood that when the limiting structure 6 is set within the spacing 22c, the limiting structure 6 abuts against the pressure ring 5 to limit the rotation of the pressure ring 5, and the limiting structure 6 is spaced from the groove wall surface 22a of the first installation groove. The heat of the pressure ring 5 can only be transferred to the limiting structure 6, and it is difficult to be transferred to the groove wall surface 22a of the first installation groove through the limiting structure 6. In this way, the influence of the heat of the pressure ring 5 on the lower plastic 2 can be reduced, and the structure of the lower plastic 2 can be prevented from being damaged due to hot melting.

[0124] See also Fig.10In other embodiments, along the radial direction of the first through hole 11, the side of the limiting structure 6 that is away from the outer peripheral surface 5a of the pressure ring is connected to the groove wall surface 22a of the first mounting groove. Specifically, when the limiting structure 6 is a boss, the boss is connected to the groove wall surface 22a of the first mounting groove along the radial direction of the first through hole 11, so that the limiting structure 6 fills the gap 22c. Exemplarily, if the limiting structure 6 is made of heat-insulating material, when the limiting structure 6 fills the gap 22c, the limiting structure 6 can play a role in heat insulation between the pressure ring 5 and the lower plastic 2, thereby helping to reduce the heat transfer from the pressure ring 5 to the lower plastic 2, and preventing the structure of the lower plastic 2 from being damaged due to hot melting.

[0125] See also Fig.11 In some embodiments, a second mounting groove 12 is provided on the side of the top cover plate 1 facing the lower plastic 2, and the second mounting groove 12 is arranged around the outer periphery of the first through hole 11. The top cover assembly 101 also includes a seal 7, which is sleeved on the outer periphery of the upper plastic 3 and located in the second mounting groove 12. Along the axial direction of the first through hole 11, the seal 7 is connected between the pressure ring 5 and the top cover plate 1. Considering the sealing installation between the pressure ring 5 and the pole 4 and the lower plastic 2 to prevent the outflow of the electrolyte in the energy storage device 100, the present application is provided with a seal 7 to form an effective sealing installation between the pressure ring 5 and the pole 4 and the lower plastic 2.

[0126] Optionally, the sealing member 7 may be a sealing ring, a sealing block, etc., which is not specifically limited in the present application.

[0127] Please refer to Figure 4 and Fig.11 , considering the installation of the seal 7, the thick thickness of the seal 7 may cause the pressure ring 5 to lift up and fail to effectively form a limiting connection with the limiting structure 6. Based on this, in some embodiments, when the limiting structure 6 is arranged in the first installation groove 22 and protrudes from the bottom surface 22b of the first installation groove, and the seal 7 is connected between the pressure ring 5 and the top cover plate 1, the pressure ring 5 compresses the seal 7, and the compression amount of the seal 7 along the axial direction of the first through hole 11 is d3, and the thickness of the limiting structure 6 is d1, wherein d1>d3. It can be understood that the thickness of the seal 7 is D1, and the thickness of the seal 7 after compression is D2, wherein D1-D2=d3. In other words, when the pressure ring 5 is installed, the seal 7 can be compressed by the pressure ring 5, and if the thickness of the limiting structure 6 is greater than the compressed thickness of the seal 7, the pressure ring 5 can form a connection with the limiting structure 6. On the contrary, if the thickness of the limiting structure 6 is less than the compressed thickness of the sealing member 7, after the sealing member 7 is compressed, the thickness of the sealing member 7 is still relatively large, which may cause the pressing ring 5 to be lifted up, thereby making it difficult for the pressing ring 5 to form a limiting connection with the limiting structure 6. In other words, when the thickness of the limiting structure 6 is greater than the compressed thickness of the sealing member 7, it is conducive to the limiting connection between the pressing ring 5 and the limiting structure 6, thereby preventing the limiting failure of the limiting structure 6.

[0128] Please also see Figures 11 to 13 In some embodiments, the upper plastic 3 is engaged with at least one of the top cover plate 1, the pole 4, and the pressure ring 5. Considering that the pressure ring 5 may be twisted and may drive the pole 4 to rotate, in order to further improve the anti-twisting effect of the pressure ring 5 and even the pole 4, the present application sets the upper plastic 3 to be engaged with the top cover plate 1, the pole 4, and the pressure ring 5, so that the upper plastic 3 is used to limit the pole 4 and the pressure ring 5, thereby preventing the pressure ring 5 and the pole 4 from rotating.

[0129] In some examples, the upper plastic 3 can be snap-fitted with the top cover plate 1 alone, the upper plastic 3 can be snap-fitted with the pole 4 alone, or the upper plastic 3 can be snap-fitted with the pressing ring 5 alone.

[0130] In other examples, the upper plastic 3 can be snap-fitted with the top cover plate 1 and the pole 4, or the upper plastic 3 can be snap-fitted with the top cover plate 1 and the pressure ring 5, or the upper plastic 3 can be snap-fitted with the pole 4 and the pressure ring 5. That is, the upper plastic 3 and the two structures are snap-fitted with each other, which is conducive to forming a chain between the upper plastic 3 and any two of the top cover plate 1, the pole 4, and the pressure ring 5, so that the upper plastic 3 has a better limiting effect on the top cover plate 1, the pole 4, and the pressure ring 5, which is conducive to further improving the restriction on the rotation of the pressure ring 5 and the pole 4.

[0131] In some other examples, the upper plastic 3 can be snap-fitted with the top cover plate 1, the pole 4 and the pressure ring 5 at the same time. The upper plastic 3 can snap-fit ​​with the top cover plate 1, the pole 4 and the pressure ring 5 at the same time. Specifically, when the top cover plate 1 is installed on the energy storage device 100, the top cover plate 1 is fixed. Since the upper plastic 3 is snap-fitted with the top cover plate 1, the position of the upper plastic 3 is fixed. Since the upper plastic 3 is snap-fitted with the pole 4 and the pressure ring 5, the position of the pressure ring 5 and the pole 4 is fixed again. In this way, layer-by-layer cooperation is formed, which is conducive to improving the stability of the upper plastic 3 limiting the top cover plate 1, the pole 4 and the pressure ring 5.

[0132] Please also see Fig.12 and Fig.13Optionally, when the upper plastic 3 is snap-fitted with the top cover plate 1, the pole 4, and the pressure ring 5, a first snap-fitting portion 31 is provided on the side of the upper plastic 3 adjacent to the pole 4, and a first matching portion 41 is provided on the pole 4 corresponding to the first snap-fitting portion 31, and one of the first snap-fitting portion 31 and the first matching portion 41 is a first protrusion, and the other is a first depression. A second snap-fitting portion 32 is provided on the side of the upper plastic 3 adjacent to the top cover plate 1, and a second matching portion 13 is provided on the top cover plate 1 corresponding to the second snap-fitting portion 32, and one of the second snap-fitting portion 32 and the second matching portion 13 is a second protrusion, and the other is a second depression. A third snap-fitting portion 33 is provided on the side of the upper plastic 3 adjacent to the pressure ring 5, and a third matching portion 53 is provided on the pressure ring 5 corresponding to the third snap-fitting portion 33, and one of the third snap-fitting portion 33 and the third matching portion 53 is a third protrusion, and the other is a third depression. In order to better form a snap connection between the upper plastic 3 and the top cover plate 1, the pole 4 and the pressure ring 5, the upper plastic 3 and the top cover plate 1, the pole 4 and the pressure ring 5 are all concave-convex fit. Fig.13 In the example, the first clamping portion 31 is a first depression, the pole 4 is provided with a first matching portion 41 which is a first protrusion, the second clamping portion 32 is a second protrusion, the second matching portion 13 of the top cover plate 1 is a second depression, and when the third clamping portion 33 is a third protrusion, the third matching portion 53 on the pressure ring 5 is a third depression. It can be seen that the matching connection between the upper plastic 3 and the top cover plate 1, the pole 4 and the pressure ring 5 is connected through its own structure, and the upper plastic 3 can be naturally locked when it is installed with the top cover plate 1, the pole 4 and the pressure ring 5, so that the effective locking between the upper plastic 3 and the top cover plate 1, the pole 4 and the pressure ring 5 is achieved without occupying additional installation space of the top cover assembly 101.

[0133] Please see again Fig.11 Optionally, when the third clamping portion 33 is a third protrusion, along the axial direction of the first through hole 11, the seal 7 of the top cover assembly 101 is located between the third clamping portion 33 and the side wall of the second through hole 21, and the thickness of the seal 7 is D1, and the thickness of the third clamping portion 33 is d4, wherein D1<d4. It is understandable that when the pressure ring 5 is installed in the first mounting groove 22, the pressure ring 5 compresses the seal 7. In order to prevent the seal 7 from being excessively deformed under the compression of the pressure ring 5 and jumping out of the second mounting groove 12, the thickness of the third clamping portion 33 of the upper plastic 3 may be greater than the thickness of the compression member, so as to prevent the deformed seal 7 from jumping out. In other words, Fig.11In the example shown, after being compressed, the seal 7 can move in the space formed by the pressure ring 5, the third clamping portion 33 and the groove wall of the second installation groove 12. Since the thickness of the third clamping portion 33 is relatively large, the movable space on one side of the seal 7 is blocked. Above the groove wall of the second installation groove 12, there is the groove wall 22a of the first installation groove, which blocks the movable space on the other side of the seal 7. The top of the seal 7 is blocked by the pressure ring 5. In this way, the movable space of the seal 7 during deformation is limited, which is beneficial to reduce the risk of the seal 7 jumping out of the second installation groove 12 when compressed by the pressure ring 5, and is beneficial to improving the sealing effect of the seal 7.

[0134] See also Fig.13 Optionally, the upper plastic 3 has a first side 3a and a second side 3b along the axial direction of the first through hole 11, the first clamping portion 31 is arranged on the first side 3a, the second clamping portion 32 and the third clamping portion 33 are both arranged on the second side 3b, and along the axial direction of the first through hole 11, the second clamping portion 32 and the third clamping portion 33 are staggered. The second clamping portion 32 and the third clamping portion 33 are arranged on the same side to avoid possible clamping interference between the second clamping portion 32, the second matching portion 13 and the third clamping portion 33, the third matching portion 53. In some examples, Fig.13 In the example, when the second clamping portion 32 and the third clamping portion 33 are correspondingly arranged on the upper plastic 3, the two are completely staggered, which is conducive to preventing the second clamping portion 32 from affecting the installation of the third clamping portion 33 and the third matching portion 53, or preventing the third clamping portion 33 from affecting the installation of the second clamping portion 32 and the second matching portion 13. In addition, when the second clamping portion 32 and the third clamping portion 33 are completely staggered, it is conducive to the alignment installation of the upper plastic 3 with the top cover plate 1 and the pressure ring 5, respectively, and facilitates the positioning installation of the upper plastic 3.

[0135] In other examples, the second clamping portion 32 and the third clamping portion 33 may be partially staggered. It is understandable that since the second clamping portion 32 and the third clamping portion 33 are respectively clamped with different structures, the clamping positions of the second clamping portion 32 and the third clamping portion 33 are located at different height positions along the axial direction of the first through hole 11. In other words, the partial staggered setting between the second clamping portion 32 and the third clamping portion 33 can also achieve effective clamping without the second clamping portion 32, the second matching portion 13 and the third clamping portion 33, the third matching portion 53.

[0136] Second, see Fig.14 The present application also discloses an energy storage device 100, comprising a housing 102, a battery cell (not shown), and a top cover assembly 101 disclosed in the first aspect. The battery cell is disposed in the housing 102, and the top cover assembly 101 is configured to cover the housing 102.

[0137] When the top cover assembly 101 disclosed in the first aspect is arranged on the energy storage device 100, the outer peripheral surface 5a of the pressure ring of the top cover assembly 101 is spaced from the groove wall surface 22a of the first mounting groove of the lower plastic 2, which is conducive to reducing the heat melting of the lower plastic 2 and preventing the structure of the lower plastic 2 from being affected, resulting in a decrease in the sealing performance of the top cover assembly 101, and causing the electrolyte in the energy storage device 100 to flow out. Moreover, a limiting structure 6 is also provided in the interval 22c between the outer peripheral surface 5a of the pressure ring and the groove wall surface 22a of the first mounting groove to limit the pressure ring 5 from twisting at the interval 22c, so as to prevent the pressure ring 5 from twisting and causing the sealing effect between the pressure ring 5 and the lower plastic 2 and the pole 4 to deteriorate, thereby preventing the electrolyte from flowing out. In addition, in order to prevent the twisting of the pressure ring 5 from driving the rotation of the pole 4, the present application also designs a clamping structure for the upper plastic 3 to further prevent the pressure ring 5 and the pole 4 from twisting and causing the sealing effect of the top cover assembly 101 to deteriorate.

[0138] It should be noted that the current energy storage (i.e., energy storage) application scenarios are relatively broad, including energy storage on the power generation side, energy storage on the grid side, and energy storage on the power consumption side. The corresponding types of energy storage devices 100 include:

[0139] (1) Large-scale energy storage power stations applied to wind power and photovoltaic power stations can help renewable energy generation meet grid connection requirements and improve the utilization rate of renewable energy. As a high-quality active / reactive regulating power source on the power supply side, energy storage power stations can achieve load matching of electric energy in time and space, enhance the ability to absorb renewable energy, reduce instantaneous power changes, reduce the impact on the power grid, improve the absorption of new energy generation, and are of great significance in power grid system backup, relieving peak load power supply pressure, and peak and frequency regulation.

[0140] (2) Energy storage containers used on the grid side mainly perform peak load regulation, frequency regulation, and grid congestion relief. They can achieve peak load shaving and valley filling of power loads, that is, charging the energy storage batteries when the power load is low and releasing the stored power during the peak load period, thereby achieving a balance between power production and consumption;

[0141] The small energy storage cabinet used on the power consumption side mainly has the functions of self-generation and self-use of electricity, peak-valley price difference arbitrage, capacity cost management and improving power supply reliability. According to different application scenarios, energy storage on the power consumption side can be divided into industrial and commercial energy storage cabinets, household energy storage devices, energy storage charging piles, etc., which are generally used in conjunction with distributed photovoltaics. Industrial and commercial users can use energy storage for valley-peak price difference arbitrage and capacity cost management. In the power market that implements peak-valley electricity prices, by charging the energy storage system 200 at low electricity prices and discharging the energy storage system 200 at high electricity prices, peak-valley electricity price difference arbitrage is achieved to reduce electricity costs. In addition, industrial enterprises that are subject to two-part electricity prices can use the energy storage system 200 to store energy during low electricity consumption and discharge it during peak loads, thereby reducing peak power and the maximum demand reported, and achieving the purpose of reducing capacity electricity charges. Household photovoltaic storage can improve the level of self-generation and self-use of electricity. Due to high electricity prices and poor power supply stability, the demand for household photovoltaic installations is driven. Considering that photovoltaic power is generated during the day, and users generally have higher loads at night, energy storage can be configured to better utilize photovoltaic power, improve the level of self-generation and self-use, and reduce electricity costs. In addition, communication base stations, data centers and other fields need to configure energy storage for backup power.

[0142] The number of energy storage devices 100 can be multiple, and multiple energy storage devices 100 are connected in series or in parallel. Multiple energy storage devices 100 are supported and electrically connected by isolation plates (not shown). In this embodiment, "multiple" refers to two or more. An energy storage box can also be provided outside the energy storage device 100 to accommodate the energy storage device 100.

[0143] Optionally, the energy storage device 100 may include but is not limited to a single cell, a battery module, a battery pack, a battery system, etc. The actual application form of the energy storage device 100 provided in the embodiment of the present application may be but is not limited to the listed products, and may also be other application forms. The embodiment of the present application does not strictly limit the application form of the energy storage device 100. The embodiment of the present application only takes the energy storage device 100 as a multi-core battery as an example for explanation. When the energy storage device 100 is a single cell, the energy storage device 100 may be at least one of a cylindrical battery, a square battery, etc.

[0144] Third, see Fig.15 The present application also discloses an energy storage system 200, comprising the energy storage device 100 disclosed in the second aspect.

[0145] In the energy storage system 200, the top cover assembly 101 of the energy storage device 100 can be set by the spacing 22c between the pressure ring 5 and the lower plastic 2 to improve the hot melting of the lower plastic 2, and the clamping design of the limiting structure 6 and the upper plastic 3 can prevent the twisting of the pressure ring 5 and the pole 4, thereby improving the leakage (electrolyte) problem of the energy storage device 100 that may be caused by the twisting of the pressure ring 5 and the pole 4.

[0146] In order to better understand the energy storage system 200 disclosed in the present application, a household energy storage scenario in user-side energy storage is taken as an example for explanation. The energy storage device 100 of the present application is not limited to a household energy storage field.

[0147] The present application provides a household energy storage system, which includes an energy conversion device 201 (photovoltaic panel), a first user load 202 (street lamp), a second user load 203 (such as household appliances such as air conditioners), etc. and an energy storage device 100, wherein the energy storage device 100 is a small energy storage box that can be mounted on an outdoor wall by wall hanging. Specifically, the photovoltaic panel can convert solar energy into electrical energy during the period of low electricity prices, and the energy storage device 100 is used to store the electrical energy and supply it to street lamps and household appliances for use during peak electricity prices, or to supply power when the power grid is out of power / power outage.

[0148] The top cover assembly, energy storage device and energy storage system disclosed in the embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the top cover assembly, energy storage device and energy storage system of the present application and their core ideas; at the same time, for general technical personnel in this field, according to the ideas of the present application, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A top cover assembly, characterized in that: include: A top cover plate, wherein the top cover plate is provided with a first through hole; A lower plastic, the lower plastic is connected to the top cover plate, a second through hole is formed in the lower plastic corresponding to the first through hole, and the second through hole is connected to the first through hole, a first mounting groove is formed on a surface of the lower plastic facing away from the top cover plate, and the first mounting groove is arranged around the outer periphery of the second through hole; A pole, wherein the pole is passed through the first through hole and the second through hole; An upper plastic, the upper plastic is arranged on the outer periphery of the pole and penetrates the first through hole and the second through hole, and the upper plastic is connected to the top cover plate; A pressure ring, the pressure ring is arranged in the first installation groove, the pressure ring is connected to the pole, and an outer peripheral surface of the pressure ring forms a gap with a groove wall surface of the first installation groove; and A limiting structure is configured to limit the rotation of the pressure ring relative to the first mounting groove around the axial direction of the first through hole.

2. The top cover assembly according to claim 1, characterized in that: The limiting structure is formed within the interval.

3. The top cover assembly according to claim 2, characterized in that: The limiting structure is arranged on the pressure ring, and / or the limiting structure is arranged on the first installation groove.

4. The top cover assembly according to claim 3, characterized in that: The outer circumferential surface of the pressure ring is configured as a non-circular surface, the limiting structure is protrudingly arranged on the bottom surface of the first mounting groove, and the limiting structure is close to or abuts against the outer circumferential surface of the pressure ring to limit the axial rotation of the pressure ring relative to the first mounting groove around the first through hole.

5. The top cover assembly according to claim 4, characterized in that: The limiting structure is arranged around the outer circumference of the pressure ring, or, The outer circumference of the pressure ring has a plurality of corners, and the limiting structure includes a plurality of limiting parts, which are arranged at intervals along the outer circumference of the pressure ring, and each of the limiting parts is arranged corresponding to each of the corners.

6. The top cover assembly according to claim 4, characterized in that: The limiting structure has an end surface along the axial direction of the first through hole, and the end surface extends to connect with the bottom surface of the first mounting groove to form a first step surface. The outer peripheral surface of the pressure ring is formed with a second step surface, and the first step surface is matched and connected with the second step surface.

7. The top cover assembly according to claim 6, characterized in that: The outer circumferential surface of the pressure ring is provided with a groove, the inner wall surface of the groove is configured as the second step surface, and the limiting structure is at least partially located in the groove so that the first step surface is close to or abuts against the second step surface.

8. The top cover assembly according to claim 4, characterized in that: Along the radial direction of the first through hole, a side of the limiting structure away from the outer peripheral surface of the pressure ring is spaced apart from the groove wall surface of the first installation groove.

9. The top cover assembly according to claim 4, characterized in that: Along the radial direction of the first through hole, a side of the limiting structure away from the outer peripheral surface of the pressure ring is connected to the groove wall surface of the first installation groove.

10. The top cover assembly according to claim 3, characterized in that: The limiting structure includes a convex portion and a concave portion. One of the pressure ring and the first mounting groove is provided with the convex portion, and the other is provided with the concave portion. The convex portion is snap-connected to the concave portion.

11. The top cover assembly according to claim 10, characterized in that: The groove wall surface of the first installation groove is provided with two protrusions, and the two protrusions are arranged at an interval to form the concave portion, and the outer peripheral surface of the protrusion and / or the convex portion is configured as an arc surface.

12. The top cover assembly according to any one of claims 2 to 11, characterized in that: The limiting structure protrudes from the bottom surface of the first mounting groove along the axial direction of the first through hole, the thickness of the limiting structure is d1, and the thickness of the pressure ring is d2, wherein d1<d2.

13. The top cover assembly according to any one of claims 1 to 11, characterized in that: A second mounting groove is provided on one side of the top cover plate facing the lower plastic, and the second mounting groove is arranged around the outer periphery of the first through hole; The top cover assembly also includes a sealing member, which is sleeved on the outer periphery of the upper plastic and located in the second mounting groove. Along the axial direction of the first through hole, the sealing member is connected between the pressure ring and the top cover plate.

14. The top cover assembly according to claim 13, characterized in that: The limiting structure is arranged in the first mounting groove and protrudes from the bottom surface of the first mounting groove. The sealing member is connected between the pressure ring and the top cover plate. The pressure ring compresses the sealing member. The compression amount of the sealing member along the axial direction of the first through hole is d3. The thickness of the limiting structure is d1, wherein d1>d3. The thickness of the sealing member is D1, and the thickness of the sealing member after being compressed is D2, wherein D1-D2=d3.

15. The top cover assembly according to claim 1, characterized in that The upper plastic is snap-fitted with at least one of the top cover plate, the pole, and the pressure ring.

16. The top cover assembly according to claim 15, characterized in that The upper plastic is snap-fitted with the top cover plate, the pole, and the pressure ring. A first snap-fitting portion is provided on one side of the upper plastic adjacent to the pole. The pole is provided with a first matching portion corresponding to the first snap-fitting portion. One of the first snap-fitting portion and the first matching portion is a first protrusion, and the other is a first depression. A second clamping portion is provided on one side of the upper plastic adjacent to the top cover plate, and a second matching portion is provided on the top cover plate corresponding to the second clamping portion, wherein one of the second clamping portion and the second matching portion is a second protrusion, and the other is a second depression; A third clamping portion is provided on one side of the upper plastic adjacent to the pressing ring, and a third matching portion is provided on the pressing ring corresponding to the third clamping portion. One of the third clamping portion and the third matching portion is a third protrusion, and the other is a third depression.

17. The top cover assembly according to claim 16, characterized in that The upper plastic has a first side and a second side along the axial direction of the first through hole, the first clamping portion is arranged on the first side, the second clamping portion and the third clamping portion are both arranged on the second side, and along the axial direction of the first through hole, the second clamping portion and the third clamping portion are staggered.

18. The top cover assembly according to claim 16, characterized in that: The top cover assembly also includes a sealing member. When the third clamping portion is a third protrusion, the sealing member is located between the third clamping portion and the side wall of the second through hole along the axial direction of the first through hole. The thickness of the sealing member is D1, and the thickness of the third clamping portion is d4, wherein D1<d4.

19. An energy storage device, characterized in that: include: case; A battery cell, wherein the battery cell is disposed in the housing; as well as The top cover assembly according to any one of claims 1-18 is configured to cover the shell.

20. An energy storage system, characterized in that: Comprising the energy storage device according to claim 19.

Images