Battery

Abstract

The utility model provides a battery which comprises a shell, a battery cell and a pressure relief assembly, the shell comprises a first side wall, the first side wall is provided with a pressure relief opening, the pressure relief opening penetrates through the two opposite faces of the first side wall in one direction, and the pressure relief opening extends in the second direction; the projection of the pressure relief assembly on the first side wall and the projection of the battery cell on the first side wall are mutually staggered, the pressure relief assembly comprises a first sealing sheet and a bonding layer, the bonding layer is bonded between the first side wall and the first sealing sheet, and the projection of the first sealing sheet on the first side wall covers the pressure relief opening. The battery disclosed by the utility model is relatively high in safety and relatively low in cost.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery. Background Art

[0002] Lithium-ion batteries are a widely used electrochemical energy storage device. Using lithium-ion batteries as an energy source can obtain stable voltage and current, and play a great role in all aspects of modern social life.

[0003] Lithium-ion batteries can use a metal shell to encapsulate battery cells and electrolytes. The metal shell can include a shell and a shell cover. The shell has a accommodating cavity with an opening on the side of the accommodating cavity. The shell cover is connected to the shell and closes the opening. In order to prevent the lithium-ion battery from exploding and catching fire, a pressure relief structure needs to be set. In the related art, grooves are cut on the shell cover to form a thinning area. When the air pressure inside the battery reaches a threshold, it ruptures to allow the gas to discharge out of the accommodating cavity. At the same time, a sealing assembly is set at the location of the injection hole of the shell. The sealing assembly may include a sealing sheet and a glue layer. The sealing sheet is bonded to the shell by the glue layer. When the temperature of the battery is high, the glue layer melts to open the injection hole, thereby discharging the hot air from the accommodating cavity.

[0004] However, when the thinning area is set on the shell cover, it cannot break and release pressure in time when the groove depth is too small, and when the groove depth is too large, it is easy to break and fail during the battery drop test, which leads to low safety of the battery. In addition, the sealing component is set at the location of the injection hole, which needs to ensure both pressure relief performance and sealing performance, which makes the structure of the sealing component more complicated, thereby increasing the cost of the battery. Utility Model Content

[0005] Based on this, the present application provides a battery to solve the deficiencies in the related art.

[0006] The battery provided in the embodiment of the present application includes a housing, a battery cell, a pressure relief assembly and a plugging member, wherein the housing includes a first side wall, the first side wall has a pressure relief port, the pressure relief port penetrates two opposite sides of the first side wall along a first direction, and the pressure relief port extends along a second direction;

[0007] The projection of the pressure relief assembly on the first side wall is staggered with the projection of the battery cell on the first side wall. The pressure relief assembly includes a first sealing sheet and an adhesive layer. The adhesive layer is bonded between the first side wall and the first sealing sheet. The projection of the first sealing sheet on the first side wall covers the pressure relief port.

[0008] In a possible implementation, the first side wall has a groove, the pressure relief port is located at the bottom wall of the groove, and the pressure relief assembly is located in the groove.

[0009] In a possible implementation manner, a side of the first sealing piece facing away from the pressure relief port is flush with the notch of the groove, or a side of the first sealing piece facing away from the pressure relief port is lower than the notch of the groove.

[0010] In a possible implementation, the adhesive layer includes an adhesive portion and an overflow portion that are connected to each other, the adhesive layer is located between the first side wall and the first sealing sheet, and the overflow portion is located on the outer peripheral side of the first sealing sheet.

[0011] In a possible implementation, a side of the overflow portion facing away from the pressure relief port is flush with a side of the first sealing piece facing away from the pressure relief port, or a side of the overflow portion facing away from the pressure relief port is lower than a side of the first sealing piece facing away from the pressure relief port.

[0012] In a possible implementation, the thickness of the adhesive layer is greater than or equal to 0.02 mm and less than or equal to 0.1 mm;

[0013] And / or, the melting point of the adhesive layer is greater than or equal to 80°C and less than or equal to 160°C.

[0014] In a possible implementation, the pressure relief assembly further includes a second sealing piece, the second sealing piece is welded to the first side wall, and the adhesive layer is bonded between the second sealing piece and the pressure relief port.

[0015] In a possible implementation, the second sealing sheet includes a metal substrate and a first coating layer, and the first coating layer is coated on a side of the metal substrate facing the adhesive layer.

[0016] In a possible implementation, the second sealing piece has a communication port, the communication port is connected to the pressure relief port, and the projection of the first sealing piece on the second sealing piece covers the communication port.

[0017] In a possible implementation, the opening area of ​​the pressure relief port is greater than or equal to 0.5 mm. 2 , and / or, the opening area of ​​the communication port is less than or equal to the opening area of ​​the pressure relief port.

[0018] In a possible implementation manner, a second plating layer is provided on the bottom wall of the groove, and the adhesive layer is bonded to the second plating layer.

[0019] In a possible implementation, the thickness of the second coating layer is greater than or equal to 0.2 um and less than or equal to 0.3 um.

[0020] In a possible implementation, the housing further includes a second side wall, and the first side wall and the second side wall are located on two adjacent sides of the housing;

[0021] The groove is located on a side of the first side wall close to the second side wall.

[0022] In a possible implementation, the groove is square, and the groove extends along the second direction;

[0023] Alternatively, the groove is triangular in shape, the groove is located at the corner of the first side wall, and adjacent side walls of the groove are connected by an arc transition.

[0024] In a possible implementation, the first sealing sheet has a first notch groove, and the thickness of the bottom wall of the first notch groove is greater than or equal to 5 um and less than or equal to 45 mm;

[0025] And / or, the width of the first notch groove is greater than or equal to 0.05 mm and less than or equal to 0.5 mm.

[0026] In a possible implementation, the second sealing sheet has a second notch groove, the second notch groove and the communication port are spaced apart along the second direction, and the projections of the first sealing sheet and the adhesive layer on the second sealing sheet both cover the communication port.

[0027] In a possible implementation, the battery provided in the embodiment of the present application further includes a blocking member, a pole and a connecting sheet, the battery cell includes a first pole ear and a second pole ear with opposite polarities, the second side wall is provided with a liquid injection hole and an avoidance hole, and the blocking member blocks the liquid injection hole;

[0028] The pole is inserted into the avoidance hole to be connected with the first pole ear, the second pole ear is connected to the inner side of the second side wall, and the connecting piece is connected to the outer side of the second side wall.

[0029] The battery provided in the present application includes a shell, a battery cell, and a pressure relief component. The shell includes a first side wall, the first side wall includes a pressure relief port, and the pressure relief component includes a first sealing sheet and an adhesive layer. The shell is provided to encapsulate the battery cell, the pressure relief port is provided to relieve pressure for the battery, the projection of the pressure relief component on the first side wall and the projection of the battery cell on the first side wall are staggered to avoid interference with the battery cell due to the pressure relief component being provided on the first side wall, thereby avoiding reducing the energy density of the battery, and the adhesive layer is provided to bond the first sealing sheet to the first side wall so that the first sealing sheet blocks the pressure relief port, and when the battery temperature reaches a preset temperature, the adhesive layer melts so that the first sealing sheet falls off from the first side wall, thereby opening the pressure relief port for pressure relief. As a result, the battery of the present application has higher safety and lower cost.

[0030] In addition to the technical problems solved by the embodiments of the present application described above, the technical features that constitute the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions, other technical problems that can be solved by the battery provided by the present application, other technical features included in the technical solutions, and the beneficial effects brought about by these technical features will be further described in detail in the specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 Schematic diagram of the structure of the battery provided in the embodiment of the present application Figure 1 ;

[0033] Figure 2 Schematic diagram of the structure of the battery provided in the embodiment of the present application Figure 2 ;

[0034] Figure 3 Schematic diagram of the structure of the battery provided in the embodiment of the present application Figure 3 ;

[0035] Figure 4 for Figure 1 An exploded view of

[0036] Figure 5 for Figure 2 An exploded view of

[0037] Figure 6 for Figure 1 Another exploded view of

[0038] Figure 7 for Figure 2 Another exploded view of

[0039] Figure 8 for Figure 3 Exploded diagram of

[0040] Fig. 9 for Figure 3 AA section view;

[0041] Fig.10 for Figure 3 BB section view;

[0042] Fig.11 for Fig. 9 A partial enlarged view of point C in the middle;

[0043] Fig.12 for Fig.10 A partial enlarged view of point D in the middle.

[0044] Description of reference numerals:

[0045] 100-housing; 110-first side wall; 111-pressure relief port; 112-groove; 120-second side wall; 121-liquid injection hole; 122-avoidance hole; 200-battery cell; 300-pressure relief assembly; 310-first sealing plate; 311-first notched groove; 320-adhesive layer; 330-second sealing plate; 331-connecting port; 332-second notched groove; 400-blocking piece; 500-pole; 600-connecting plate. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme in the embodiment of the present application will be described in more detail below in conjunction with the drawings in the preferred embodiments of the present application. In the drawings, the same or similar reference numerals throughout represent the same or similar parts or parts with the same or similar functions. The described embodiments are part of the embodiments of the present application, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application. The embodiments of the present application are described in detail below in conjunction with the drawings.

[0047] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, or it can be an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0048] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are orientations or positional relationships based on the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0049] The terms "first", "second", "third" (if any) in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the application described herein can be implemented in an order other than those illustrated or described herein, for example.

[0050] In addition, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product, or display comprising a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such process, method, product, or display.

[0051] In the related art, a through hole for liquid injection and a through hole for pressure relief are provided on the battery casing. The through hole for liquid injection and the through hole for pressure relief can be combined into one, that is, a through hole is provided on the battery casing, and an explosion-proof plate is bonded to the battery casing through an adhesive layer to close the through hole. In this way, electrolyte can be injected through the through hole, and pressure can be relieved through the through hole. However, because this explosion-proof plate not only needs to consider explosion-proof performance but also sealing performance, the structure of the explosion-proof plate and the adhesive layer is relatively complicated, resulting in a higher cost of the battery.

[0052] Lithium-ion batteries can use a metal shell to encapsulate battery cells and electrolytes. The metal shell can include a shell and a shell cover. The shell has a accommodating cavity with an opening on the side of the accommodating cavity. The shell cover is connected to the shell and closes the opening. In order to prevent the lithium-ion battery from exploding and catching fire, a pressure relief structure needs to be set. In the related art, grooves are cut on the shell cover to form a thinning area. When the air pressure inside the battery reaches a threshold, it ruptures to allow the gas to discharge out of the accommodating cavity. At the same time, a sealing assembly is set at the location of the injection hole of the shell. The sealing assembly may include a sealing sheet and a glue layer. The sealing sheet is bonded to the shell by the glue layer. When the temperature of the battery is high, the glue layer melts to open the injection hole, thereby discharging the hot air from the accommodating cavity.

[0053] However, when the thinning area is set on the shell cover, it cannot break and release pressure in time when the groove depth is too small, and when the groove depth is too large, it is easy to break and fail during the battery drop test, which leads to low safety of the battery. In addition, the sealing component is set at the location of the injection hole, which needs to ensure both pressure relief performance and sealing performance, which makes the structure of the sealing component more complicated, thereby increasing the cost of the battery.

[0054] In view of the above problems, an embodiment of the present application provides a battery, wherein the first side wall of the shell is provided with a pressure relief port, the pressure relief port is sealed by a pressure relief assembly, and the projection of the pressure relief assembly on the first side wall and the projection of the battery cell on the first side wall are staggered with each other, so as to avoid interference between the pressure relief assembly and the battery cell, resulting in a reduction in the energy density of the battery, wherein the pressure relief assembly includes a first sealing sheet and an adhesive layer, and when the battery temperature reaches a preset temperature, the adhesive layer melts, thereby allowing the first sealing sheet to open the pressure relief port to release pressure, thereby solving the problem in the related art that it is difficult to accurately control the groove depth and the problem of high battery cost.

[0055] The specific implementation of the battery provided in the embodiments of the present application is described in detail below with reference to the accompanying drawings.

[0056] Reference Figures 1 to 5 As shown, the battery provided in the embodiment of the present application includes a shell 100, a battery cell 200, a pressure relief assembly 300 and a sealing member 400, the shell 100 includes a first side wall 110 and a second side wall 120, the first side wall 110 and the second side wall 120 are located on two adjacent sides of the shell 100, the first side wall 110 has a pressure relief port 111, the second side wall 120 has a liquid injection hole 121, and the liquid injection hole 121 and the pressure relief port 111 are both connected to the inner and outer sides of the shell 100.

[0057] The pressure relief port 111 penetrates two opposite sides of the first side wall 110 along the first direction, the pressure relief port 111 extends along the second direction, the injection hole 121 penetrates two opposite sides of the second side wall 120 along the third direction, the first direction is along the thickness direction of the battery cell 200, the second direction is perpendicular to the first direction, and the third direction is perpendicular to both the first direction and the second direction. The first direction can refer to Figure 4 The X direction in the second direction can refer to Figure 4 The Y direction in the third direction can refer to Figure 4 The Z direction in .

[0058] The projection of the pressure relief assembly 300 on the first side wall 110 and the projection of the battery cell 200 on the first side wall 110 are staggered, and the pressure relief assembly 300 includes a first sealing sheet 310 and an adhesive layer 320, the adhesive layer 320 is bonded between the first side wall 110 and the first sealing sheet 310, and the projection of the first sealing sheet 310 on the first side wall 110 covers the pressure relief port 111. The blocking member 400 is connected to the second side wall 120 to block the injection hole 121.

[0059] In the present application, the shell 100 is used to encapsulate the battery cell 200. The shell 100 can be box-shaped. The shell 100 has a first side wall 110 and a second side wall 120 adjacent to each other, and the first side wall 110 is provided with a pressure relief port 111. The pressure relief port 111 is used to open and relieve pressure when the battery temperature is high or the pressure is high. The second side wall 120 has an injection hole 121. The injection hole 121 is used to inject electrolyte into the shell 100.

[0060] In order to seal the injection hole 121 , the battery may further include a blocking member 400 , which is welded to the second side wall 120 to seal the injection hole 121 , thereby preventing the electrolyte from leaking from the injection hole 121 later.

[0061] Compared with the method of combining the pressure relief hole and the injection hole 121 into one, the pressure relief hole and the injection hole 121 are respectively arranged on the adjacent first side wall 110 and the second side wall 120, which is conducive to reducing the structural complexity of the battery and thus reducing the cost of the battery. The axial direction of the injection hole 121 is consistent with the length direction of the battery cell 200, so that the electrolyte can fully infiltrate the pole piece of the battery cell 200.

[0062] In order to close the pressure relief port 111, the battery may further include a pressure relief assembly 300. When the pressure relief hole and the liquid injection hole 121 are respectively located on two adjacent sides of the outer shell 100, in order to avoid the pressure relief assembly 300 from interfering with the battery cell 200 and forcing the battery cell 200 to reduce its volume, the pressure relief assembly 300 should avoid overlapping with the battery cell 200, that is, the projection of the pressure relief assembly 300 on the first side wall 110 and the projection of the battery cell 200 on the first side wall 110 should be staggered with each other. In this way, the battery can achieve a higher benefit between the difficulty of manufacturing the battery cell 200 and the energy density of the battery cell 200.

[0063] Specifically, the pressure relief seal may include a first sealing piece 310 and an adhesive layer 320. The adhesive layer 320 is sticky and can adhere the first seal to the first side wall 110, thereby allowing the first sealing piece 310 to block the pressure relief port 111. At the same time, when the surrounding temperature reaches its own melting point, the adhesive layer 320 will change from a solid state to a molten state, thereby causing the first sealing piece 310 to fall off the first side wall 110, thereby opening the pressure relief port 111 for pressure relief.

[0064] In addition, in the related art, grooves are directly carved on the shell cover to form a thinning area. When the internal pressure of the battery exceeds the preset pressure, the thinning area is broken to achieve pressure relief. However, it takes a certain amount of time for the preset pressure to be reached inside the battery, and the pressure cannot be relieved when the preset pressure is not reached inside the battery. Secondly, the depth of the groove is difficult to control. If the groove depth is too small, it cannot be broken and pressure relieved in time. If the groove depth is too large, it is easy to break and fail during the battery drop test. The above reasons lead to low flexibility and timeliness of pressure relief. The battery provided in the present application utilizes the physical properties of the adhesive layer 320 so that the battery can determine whether to relieve pressure according to the temperature. Compared with the existing method of setting a thinning area, the flexibility and timeliness of pressure relief are improved, and serious damage or explosion due to gas accumulation inside the battery is avoided.

[0065] The battery provided in the embodiment of the present application includes a shell 100, a battery cell 200, a pressure relief assembly 300 and a sealing member 400, the shell 100 includes a first side wall 110 and a second side wall 120, the first side wall 110 includes a pressure relief port 111, the second side wall 120 includes a liquid injection hole 121, and the pressure relief assembly 300 includes a first sealing sheet 310 and an adhesive layer 320. A shell 100 is provided to encapsulate the battery cell 200, a pressure relief port 111 is provided to relieve pressure for the battery, an injection hole 121 is provided to inject electrolyte into the battery, and a sealing member 400 is provided to seal the injection hole 121 to prevent subsequent leakage of electrolyte from the injection hole 121. The projection of the pressure relief component 300 on the first side wall 110 and the projection of the battery cell 200 on the first side wall 110 are staggered to avoid interference with the battery cell 200 due to the pressure relief component 300 on the first side wall 110, thereby avoiding reduction in the energy density of the battery. An adhesive layer 320 is provided to bond the first sealing sheet 310 to the first side wall 110 so that the first sealing sheet 310 blocks the pressure relief port 111. When the battery temperature reaches a preset temperature, the adhesive layer 320 melts so that the first sealing sheet 310 falls off from the first side wall 110, thereby opening the pressure relief port 111 for pressure relief. Therefore, the battery provided by the embodiments of the present application has higher safety and lower cost.

[0066] Reference Figure 4 and Figure 5 As shown, in a possible implementation, the first side wall 110 has a groove 112, the pressure relief port 111 is located at the bottom wall of the groove 112, the pressure relief assembly 300 matches the shape of the groove 112, and the pressure relief assembly 300 is located in the groove 112, and the side of the first sealing piece 310 facing away from the pressure relief port 111 is flush with the notch of the groove 112, or the side of the first sealing piece 310 facing away from the pressure relief port 111 is lower than the notch of the groove 112.

[0067] It should be noted that if the first side wall 110 is not provided with the groove 112, then after the first sealing sheet 310 is bonded to the first side wall 110 through the adhesive layer 320, the pressure relief assembly 300 will protrude from the outer surface of the first side wall 110. By providing the groove 112 on the first side wall 110, and providing the pressure relief port 111 on the bottom wall of the groove 112, and then sealing the pressure relief port 111 by the pressure relief assembly 300, the pressure relief assembly 300 can be located in the groove 112, so that the surface of the first sealing sheet 310 will not protrude from the groove 112, and the first side wall 110 will have no protrusion, thereby avoiding increasing the ineffective volume of the battery.

[0068] It can be understood that when the adhesive layer 320 is used to bond the first sealing piece 310 and the first side wall 110, since the adhesive layer 320 has a certain fluidity after being heated and melted, part of the adhesive layer 320 will overflow from the first sealing piece 310 after solidification. Therefore, in a possible implementation, the adhesive layer 320 includes an interconnected adhesive portion and an overflow portion, the adhesive layer 320 is located between the first side wall 110 and the first sealing piece 310, and the overflow portion is located on the outer peripheral side of the first sealing piece 310.

[0069] In some embodiments, the side of the overflow portion facing away from the pressure relief port 111 is flush with the side of the first sealing piece 310 facing away from the pressure relief port 111, or the side of the overflow portion facing away from the pressure relief port 111 is lower than the side of the first sealing piece 310 facing away from the pressure relief port 111. In this way, the overflowed portion of the adhesive layer 320 can be prevented from exceeding the first sealing piece 310, thereby preventing the pressure relief assembly 300 from exceeding the groove 112.

[0070] In a possible implementation, the thickness of the adhesive layer 320 is greater than or equal to 0.02 mm and less than or equal to 0.1 mm, and / or the melting point of the adhesive layer 320 is greater than or equal to 80° C. and less than or equal to 160° C.

[0071] When the thickness of the adhesive layer 320 is less than 0.02 mm, the distance between the first sealing sheet 310 and the first side wall 110 is relatively close, and the battery is in danger of short circuit. In addition, the adhesive force of the adhesive layer 320 is relatively small, and the first sealing sheet 310 and the first side wall 110 cannot be effectively connected. When the thickness of the adhesive layer 320 is greater than 0.1 mm, the volume of the adhesive layer 320 is relatively large, and it is difficult for the adhesive layer 320 to completely melt so that the first sealing sheet 310 falls off. In addition, the liquid easily penetrates into the interior of the housing 100 from between the first sealing sheet 310 and the first side wall 110 through the adhesive layer 320. Therefore, the thickness of the adhesive layer 320 is set to 0.02 mm to 0.1 mm, which is conducive to improving the timeliness and effectiveness of pressure relief.

[0072] If the melting point of the adhesive layer 320 is too high, it will be difficult for the adhesive layer 320 to melt in time to open the pressure relief port 111 for pressure relief. If the melting point of the adhesive layer 320 is too low, the adhesive layer 320 will melt in advance, thereby causing the battery to release pressure in advance. Therefore, setting the melting point of the adhesive layer 320 between 80°C and 160°C is conducive to the melting of the adhesive layer 320 when the temperature inside or outside the battery is too high, thereby further enhancing the timeliness and effectiveness of the pressure relief.

[0073] The adhesive layer 320 may be formed of a single material or a combination of multiple materials.

[0074] For example, the thickness of the adhesive layer 320 may be any one of 0.02 mm, 0.05 mm, 0.07 mm, and 0.1 mm, or may be within any two numerical ranges. And / or, the melting point of the adhesive layer 320 may be any one of 80° C., 110° C., 130° C., 150° C., and 180° C., or may be within any two numerical ranges.

[0075] Reference Figures 6 to 8 As shown, in some embodiments, the pressure relief assembly 300 further includes a second sealing piece 330 , the second sealing piece 330 is welded to the first side wall 110 , and the adhesive layer 320 is bonded between the second sealing piece 330 and the pressure relief port 111 .

[0076] Therefore, by setting the second sealing film 330 between the first side wall 110 and the adhesive layer 320, the connection strength between the adhesive layer 320 and the first side wall 110 can be improved to avoid the adhesive layer 320 directly adhering to the first side wall 110, which would result in insufficient bonding force between the adhesive layer 320 and the first side wall 110.

[0077] Alternatively, when the first side wall 110 is directly made of a nickel sheet, the second sealing sheet 330 may not be disposed between the adhesive layer 320 and the first side wall 110 .

[0078] In a specific implementation, the second sealing sheet 330 includes a metal substrate and a first coating layer, and the first coating layer is coated on a side of the metal substrate facing the adhesive layer 320 .

[0079] The first coating may be a nickel layer, which can improve the bonding force between the second sealing sheet 330 and the adhesive layer 320, and improve the anti-corrosion performance of the second sealing sheet 330.

[0080] Reference Figure 7 and Figure 8 As shown, in a possible implementation, the projection of the second sealing piece 330 on the first side wall 110 covers the pressure relief port 111, the second sealing piece 330 has a connecting port 331, the connecting port 331 is connected to the pressure relief port 111, and the projection of the first sealing piece 310 on the second sealing piece 330 covers the connecting port 331.

[0081] In this way, when the adhesive layer 320 is heated and melted, the first sealing piece 310 can be separated from the second sealing piece 330, and then the first sealing piece 310 can fall off from the first side wall 110, so that the pressure relief port 111 and the connecting port 331 are connected in sequence, and then the inside of the outer shell 100 and the outside of the outer shell 100 are connected, thereby discharging the gas inside the battery.

[0082] In a possible implementation, the opening area of ​​the pressure relief port 111 is greater than or equal to 0.5 mm. 2, the opening area of ​​the communication port 331 is less than or equal to the opening area of ​​the pressure relief port 111. With such a configuration, the projection of the communication port 331 on the first side wall 110 can at least partially overlap with the pressure relief port 111, so that the communication port 331 and the pressure relief port 111 are in a communication state, and at the same time, the projection of the communication port 331 on the first side wall 110 can at least partially stagger with the pressure relief port 111, so as to ensure the sealing of the pressure relief port 111 after the pressure relief assembly 300 closes the pressure relief port 111, thereby preventing leakage of electrolyte.

[0083] In some embodiments, the bottom wall of the groove 112 is provided with a second plating layer, and the adhesive layer 320 is bonded to the second plating layer. It should be noted that when the second sealing sheet 330 is not provided between the adhesive layer 320 and the bottom wall of the groove 112, the second plating layer can be provided on the bottom wall of the groove 112 to improve the bonding force between the adhesive layer 320 and the first side wall 110, thereby improving the connection strength between the adhesive layer 320 and the first side wall 110. The second plating layer can be a nickel layer.

[0084] Alternatively, when the first side wall 110 is directly made of stainless steel, the second plating layer may not be provided on the bottom wall of the groove 112 .

[0085] In some embodiments, the thickness of the second coating layer is greater than or equal to 0.2 um and less than or equal to 0.3 um. In this way, it is possible to avoid the second coating layer being too thick, thereby occupying more space in the groove 112, resulting in insufficient space in the groove 112 for the pressure relief assembly 300 to be accommodated in the groove 112. At the same time, it is possible to avoid the second coating layer being too thin, thereby reducing the connection strength between the adhesive layer 320 and the first side wall 110.

[0086] Exemplarily, the thickness of the second coating layer may be any one of 0.2um, 0.25um, 0.28um, and 0.3um, or may be within a range of any two values.

[0087] In a possible implementation, the first side wall 110 is square, and the groove 112 is located on a side of the first side wall 110 close to the second side wall 120. In this way, the projection of the pressure relief assembly 300 on the first side wall 110 and the projection of the battery cell 200 on the first side wall 110 can be staggered, and the projection of the battery cell 200 on the first side wall 110 and the groove 112 can be staggered.

[0088] It should be noted that, since the groove 112 can be formed by the first side wall 110 sinking toward the inside of the shell 100, the groove 112 is provided on the side of the first side wall 110 facing away from the battery cell 200, and accordingly, a protrusion is formed on the side of the first side wall 110 facing the battery cell 200. If the groove 112 is set in the middle position of the first side wall 110, the protrusion is easy to interfere with the battery cell 200.

[0089] Reference Figures 1 to 4 , Figure 6 , Figure 8 As shown, in a possible implementation, the groove 112 is square, and the length direction of the groove 112 is along the second direction.

[0090] Reference Figure 2 , Figure 5 and Figure 7 As shown, or, the groove 112 is triangular, the groove 112 is located at the corner of the first side wall 110, and adjacent side walls of the groove 112 are connected by arc transition.

[0091] Since the shape of the pressure relief component 300 matches the shape of the groove 112, when the groove 112 is square, the outer contours of the first sealing piece 310, the adhesive layer 320 and the second sealing piece 330 are also square; when the groove 112 is triangular, the outer contours of the first sealing piece 310, the adhesive layer 320 and the second sealing piece 330 are also triangular.

[0092] In addition, when the groove 112 is triangular, the groove 112 is disposed at the corner of the first side wall 110 and is disposed close to the second side wall 120 , so that a balance can be achieved between the manufacturing difficulty of the battery cell 200 and the energy density of the battery cell 200 .

[0093] Reference Figure 4 As shown in Fig. 6, in a possible implementation, the first sealing sheet 310 has a first notch groove 311, and the thickness of the bottom wall of the first notch groove 311 is greater than or equal to 5um and less than or equal to 45mm. And / or, the width of the first notch groove 311 is greater than or equal to 0.05mm and less than or equal to 0.5mm.

[0094] In this way, by partially thinning the first sealing sheet 310 to form the first notched groove 311, when the pressure inside the battery reaches a preset pressure, the gas breaks through the first notched groove 311 to connect the inner and outer sides of the housing 100, thereby releasing the pressure. When the battery temperature reaches a preset temperature, the first sealing sheet 310 falls off from the first side wall 110 to open the pressure relief hole to release the pressure. The battery can have two pressure relief methods to improve the safety performance of the battery.

[0095] It is understandable that if the thickness of the bottom wall of the first notched groove 311 is less than 5um, the thickness of the bottom wall of the first notched groove 311 will be too thin, which will easily cause the first notched groove 311 to be damaged in advance and cause the battery to release pressure in advance. If the thickness of the bottom wall of the first notched groove 311 is greater than 45mm, the thickness of the first notched groove 311 will be too thick, which will cause the first notched groove 311 to be damaged in time and cause the battery to release pressure in a delayed manner. Therefore, setting the thickness of the bottom wall of the first notched groove 311 between 5um and 45mm can prevent the first sealing piece 310 from releasing pressure in advance and delay the pressure release of the first sealing piece 310.

[0096] If the width of the first notch groove 311 is less than 0.05 mm, the opening area is small, which is not conducive to rapid pressure release. If the width of the second notch groove 332 is greater than 0.5 mm, the structural strength of the first sealing sheet 310 will be reduced. Therefore, setting the width of the first notch groove 311 between 0.05 mm and 0.5 mm is a more reasonable range.

[0097] For example, the thickness of the bottom wall of the first notch groove 311 may be any one of 5 μm, 30 μm, 80 μm, 35 mm, and 45 mm, or may be within any two numerical ranges. And / or, the width of the first notch groove 311 may be any one of 0.05 mm, 0.1 mm, 0.3 mm, and 0.5 mm, or may be within any two numerical ranges.

[0098] Reference Figures 8 to 12 As shown, in a possible implementation, the second sealing piece 330 has a second notched groove 332, and the second notched groove 332 and the connecting port 331 are spaced apart along the length direction of the pressure relief port 111, that is, the second notched groove 332 and the connecting port 331 are spaced apart along the second direction, and the projections of the first sealing piece 310 and the adhesive layer 320 on the second sealing piece 330 are staggered with the second notched groove 332, and the projections of the first sealing piece 310 and the adhesive layer 320 on the second sealing piece 330 both cover the connecting port 331.

[0099] In the above configuration, the second sealing sheet 330 has both the second notched groove 332 and the connecting port 331, and the second notched groove 332 and the connecting port 331 are arranged at intervals, and the second notched groove 332 is used to rupture and release pressure when the battery pressure reaches a preset pressure.

[0100] In addition to the connecting port 331, the projection of the second sealing piece 330 on the first side wall 110 covers the pressure relief port 111, and the first sealing piece 310 blocks the connecting port 331. In this way, the first sealing piece 310 and the second sealing piece 330 can seal the pressure relief port 111 together. The adhesive layer 320 is used to change from a solid state to a molten state when the battery temperature reaches a preset temperature, thereby allowing the first sealing piece 310 to open the connecting port 331, thereby opening the pressure relief port 111 for pressure relief.

[0101] The thickness of the bottom wall of the second notch groove 332 is greater than or equal to 5 um and less than or equal to 45 mm; and / or the width of the second notch groove 332 is greater than or equal to 0.05 mm and less than or equal to 0.5 mm.

[0102] Such a configuration allows the bottom wall of the second notched groove 332 to rupture in time when the battery pressure reaches a preset pressure to start pressure relief, thereby avoiding delayed opening and premature opening, and allowing the second sealing piece 330 to form an opening large enough to release pressure while ensuring the structural strength of the second sealing piece 330.

[0103] For example, the thickness of the bottom wall of the second notch groove 332 may be any one of 5 μm, 40 μm, 90 μm, 20 mm, and 45 mm, or be within any two numerical ranges. And / or, the width of the second notch groove 332 may be any one of 0.05 mm, 0.15 mm, 0.25 mm, and 0.5 mm, or be within any two numerical ranges.

[0104] Refer to 1 to Figure 8 As shown, in a possible implementation, the battery provided in the embodiment of the present application also includes a pole 500 and a connecting plate 600, the battery cell 200 includes a first pole ear and a second pole ear with opposite polarities, the second side wall 120 is provided with an avoidance hole 122, the pole 500 is inserted in the avoidance hole 122 to be connected to the first pole ear, the second pole ear is connected to the inner side of the second side wall 120, the connecting plate 600 is connected to the outer side of the second side wall 120, and is constructed to be connected to the device to be powered.

[0105] In this way, the pole 500 can lead the current of the first pole ear to the device to be powered, and the shell 100 can lead the current of the second pole ear. When the wall thickness of the shell 100 is relatively small, the second side wall 120 can be locally thickened by welding the connecting piece 600 on the second side wall 120 to facilitate the connection between the second side wall 120 and the device to be powered, thereby leading the current of the second pole ear to the device to be powered.

[0106] The housing 100 may be made of metal material, such as an aluminum housing or a steel housing.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery, characterized in that: The invention comprises a housing, a battery cell and a pressure relief assembly, wherein the housing comprises a first side wall, the first side wall has a pressure relief opening, the pressure relief opening penetrates two opposite sides of the first side wall along a first direction, and the pressure relief opening extends along a second direction; The projection of the pressure relief assembly on the first side wall and the projection of the battery cell on the first side wall are staggered with each other. The pressure relief assembly includes a first sealing sheet and an adhesive layer. The adhesive layer is bonded between the first side wall and the first sealing sheet. The projection of the first sealing sheet on the first side wall covers the pressure relief port.

2. The battery according to claim 1, characterized in that The first side wall has a groove, the pressure relief port is located at the bottom wall of the groove, and the pressure relief assembly is located in the groove.

3. The battery according to claim 2, characterized in that A side of the first sealing piece facing away from the pressure relief port is flush with the notch of the groove, or a side of the first sealing piece facing away from the pressure relief port is lower than the notch of the groove.

4. The battery according to claim 1 or 2, characterized in that: The adhesive layer includes an adhesive portion and an overflow portion which are connected to each other. The adhesive layer is located between the first side wall and the first sealing sheet. The overflow portion is located on the outer peripheral side of the first sealing sheet.

5. The battery according to claim 4, characterized in that A side of the overflow portion facing away from the pressure relief port is flush with a side of the first sealing piece facing away from the pressure relief port, or a side of the overflow portion facing away from the pressure relief port is lower than a side of the first sealing piece facing away from the pressure relief port.

6. The battery according to claim 1 or 2, characterized in that: The thickness of the adhesive layer is greater than or equal to 0.02 mm and less than or equal to 0.1 mm; And / or, the melting point of the adhesive layer is greater than or equal to 80°C and less than or equal to 160°C.

7. The battery according to claim 1 or 2, characterized in that: It also includes a second sealing piece, wherein the second sealing piece is welded to the first side wall, and the adhesive layer is bonded between the second sealing piece and the pressure relief port; The second sealing piece has a communication port, the communication port is connected to the pressure relief port, and the projection of the first sealing piece on the second sealing piece covers the communication port.

8. The battery according to claim 7, characterized in that The second sealing sheet includes a metal substrate and a first coating, wherein the first coating is coated on a surface of the metal substrate facing the adhesive layer.

9. The battery according to claim 7, characterized in that The opening area of ​​the pressure relief port is greater than or equal to 0.5 mm 2 , and / or, The opening area of ​​the communication port is smaller than or equal to the opening area of ​​the pressure relief port.

10. The battery according to claim 2, characterized in that The bottom wall of the groove is provided with a second plating layer, and the adhesive layer is bonded to the second plating layer.

11. The battery according to claim 10, characterized in that The thickness of the second coating layer is greater than or equal to 0.2 um and less than or equal to 0.3 um.

12. The battery according to claim 2, characterized in that The housing further comprises a second side wall, wherein the first side wall and the second side wall are located on two adjacent sides of the housing; The groove is located on a side of the first side wall close to the second side wall.

13. The battery according to claim 12, characterized in that The groove is square in shape, and extends along the second direction; Alternatively, the groove is triangular in shape, the groove is located at a corner of the first side wall, and adjacent side walls of the groove are connected by an arc transition.

14. The battery according to claim 1 or 2, characterized in that: The first sealing sheet has a first notch groove, and the thickness of the bottom wall of the first notch groove is greater than or equal to 5 um and less than or equal to 45 mm; And / or, the width of the first notch groove is greater than or equal to 0.05 mm and less than or equal to 0.5 mm.

15. The battery according to claim 7, characterized in that The second sealing sheet has a second notch groove, the second notch groove and the communication opening are spaced apart along the second direction, and the projections of the first sealing sheet and the adhesive layer on the second sealing sheet both cover the communication opening.

16. The battery according to claim 13, characterized in that It also includes a blocking piece, a pole and a connecting piece, the battery cell includes a first pole ear and a second pole ear with opposite polarities, the second side wall is provided with a liquid injection hole and an avoidance hole, and the blocking piece blocks the liquid injection hole; The pole is inserted into the avoidance hole, the pole is connected to the first pole lug, the second pole lug is connected to the inner side of the second side wall, and the connecting piece is connected to the outer side of the second side wall.

Images