A battery case and a battery including the same

Abstract

The utility model relates to battery technical field discloses a kind of battery shell and battery including the battery shell of this battery shell, the battery shell includes conductive shell, insulating adhesive layer and expansion adhesive layer;The conductive shell includes bottom wall and side wall, the bottom wall and the side wall form and have accommodating cavity;The conductive shell has the opening of the accommodating cavity intercommunication;The inner wall surface of the side wall is coated with the insulating adhesive layer;The expansion adhesive layer is coated with the inner wall surface of the insulating adhesive layer side away from the side wall, the expansion adhesive layer and the inner wall surface of the bottom wall are spaced, the expansion adhesive layer and the opening are spaced;Battery shell provided in the utility model can reduce the risk of short circuit in battery and improve the overall reliability of battery by setting insulating adhesive layer and expansion adhesive layer on side wall.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery casing and a battery including the battery casing. Background Technology

[0002] In the field of battery manufacturing technology, some batteries use conductive materials to make conductive casings that house the battery cells. The negative electrode tab of the battery cell is welded to the bottom of the conductive casing and electrically connected, making the entire conductive casing connected to the negative electrode of the battery cell and energized. At the same time, the positive electrode tab is welded to the cap and electrically connected. At the positive terminal of the battery cell, there is a risk of contact between the conductive casing and the positive terminal of the battery cell. Once they come into contact, it will cause an internal short circuit in the battery. At the same time, due to the gap between the outer wall of the battery cell and the inner wall of the conductive casing, when the battery is subjected to severe vibration, rolling or other conditions, the battery cell will shake inside the conductive casing. This shaking will generate tensile force on the welded joints of the battery cell tabs. Long-term or severe pulling may cause the tabs to break or cause weak welds in the original welded joints, reducing the overall reliability of the battery. Utility Model Content

[0003] With the aim of at least solving one of the technical problems existing in the prior art, this utility model aims to provide a battery casing and a battery including the battery casing, wherein the battery casing can reduce the risk of internal short circuit in the battery and improve the overall reliability of the battery.

[0004] To achieve the above objectives, this utility model provides a battery casing with a first orientation. The battery casing includes a conductive casing, an insulating adhesive layer, and an expanding adhesive layer. The conductive casing includes a bottom wall and a side wall, with the bottom wall and the side wall connected at one end in the first orientation, forming a receiving cavity. The conductive casing has an opening communicating with the receiving cavity at the end in the first orientation away from the bottom wall. The inner wall surfaces of the side walls are coated with the insulating adhesive layer. The expanding adhesive layer is coated on the side of the insulating adhesive layer facing away from the inner wall surface of the side wall. The expanding adhesive layer and the inner wall surface of the bottom wall are spaced apart, and the expanding adhesive layer and the opening are spaced apart.

[0005] In some embodiments, the thickness of the insulating adhesive layer is a μm, satisfying: 1 ≤ a ≤ 10.

[0006] In some embodiments, the thickness of the expanding adhesive layer is b μm, satisfying: 3 ≤ b ≤ 30.

[0007] In some embodiments, there are multiple expanding adhesive layers, and the multiple expanding adhesive layers are spaced apart along the first direction.

[0008] In some embodiments, the number of expanding adhesive layers is three, comprising a first expanding adhesive layer, a second expanding adhesive layer, and a third expanding adhesive layer. The first expanding adhesive layer, the second expanding adhesive layer, and the third expanding adhesive layer are spaced apart along the first direction, with the second expanding adhesive layer located between the first expanding adhesive layer and the third expanding adhesive layer. Along the first direction, the size of the receiving cavity is H mm, the size of the first expanding adhesive layer is K1 mm, the size of the second expanding adhesive layer is K2 mm, and the size of the third expanding adhesive layer is K3 mm, satisfying: 0.05Hmm≤K1≤0.15Hmm, 0.05Hmm≤K2≤0.15Hmm, 0.05Hmm≤K3≤0.15Hmm.

[0009] In some implementations, K1 = 0.1Hmm, K2 = 0.1Hmm, and K3 = 0.1Hmm.

[0010] In some embodiments, along the first direction, the distance between the first expanded adhesive layer and the inner wall surface of the bottom wall is L1 mm, satisfying: 0.15H≤L1≤0.25H.

[0011] In some embodiments, along the first direction, the distance between the second expanding adhesive layer and the inner wall surface of the bottom wall is L2mm, satisfying: 0.45H≤L2≤0.55H.

[0012] In some embodiments, along the first direction, the distance between the third expanding adhesive layer and the inner wall surface of the bottom wall is L3 mm, satisfying: 0.7H ≤ L3 ≤ 0.8H

[0013] This utility model also provides a battery, the battery including a battery casing according to any one of the above claims, and further including an electrolyte, a battery cell, a cover plate, and a cap. The electrolyte and the battery cell are contained in the containing cavity. The negative electrode tab of the battery cell is welded to the bottom wall and electrically connected. The outer wall surface of the battery cell and the inner wall surface of the side wall have a gap. The expanding adhesive layer is located in the gap, and the side of the expanding adhesive layer away from the insulating adhesive layer abuts against the outer wall surface of the battery cell. The cover plate is connected to the end of the side wall away from the bottom wall and seals the opening. The cover plate has a through hole communicating with the containing cavity. The cap passes through the through hole, and the outer wall surface of the cap is connected to the hole wall of the through hole. The cover plate and the cap are insulated from each other. The positive electrode tab of the battery cell is welded to the cap and electrically connected.

[0014] Compared with the prior art, the battery casing of this utility model has the following advantages: (1) By coating the inner wall surface of the side wall with an insulating adhesive layer, when the battery cell is contained in the cavity, the insulating adhesive layer can form an insulating barrier between the inner wall surface of the side wall and the positive electrode of the battery cell, thereby reducing the risk of accidental contact between the conductive casing and the positive electrode of the battery cell at the positive terminal and reducing the risk of internal short circuit of the battery.

[0015] (2) By setting an expanding adhesive layer on the side of the insulating adhesive layer away from the sidewall, after the electrolyte is injected into the cavity containing the battery cell, the expanding adhesive layer will expand after absorbing the electrolyte and fill the gap between the outer wall surface of the battery cell and the inner wall surface of the sidewall, so as to fix the battery cell firmly in the cavity. When the battery encounters severe vibration, rolling or other working conditions, the expansion adhesive layer can fix the battery cell, which can limit the shaking of the battery cell in the cavity, avoid the shaking of the battery cell from generating a pulling force on the electrode welding joint, prevent the electrode from being torn or poorly welded, thereby stabilizing the internal resistance of the battery cell and improving the overall reliability of the battery.

[0016] (3) By keeping the expansion adhesive layer and the inner wall surface and opening of the bottom wall at intervals, space can be reserved in the cavity to store the gas generated by the battery cell during use, so as to avoid triggering the battery current interruption device due to excessive gas in the cavity. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a battery casing provided in an embodiment of the present invention;

[0018] Figure 2 This is a cross-sectional view of a battery casing provided in an embodiment of the present invention;

[0019] Figure 3 yes Figure 2 Enlarged view of point A;

[0020] Figure 4 This is a cross-sectional view of a battery provided in an embodiment of this utility model.

[0021] In the diagram, 1 is the conductive housing; 10 is the receiving cavity; 11 is the bottom wall; 12 is the side wall; and 13 is the opening.

[0022] 2. Insulating adhesive layer;

[0023] 3. Expanding adhesive layer; 31. First expanding adhesive layer; 32. Second expanding adhesive layer; 33. Third expanding adhesive layer;

[0024] 100, battery cell; 200, cover plate; 300, cap;

[0025] Z, First direction. Detailed Implementation

[0026] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.

[0027] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0028] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0029] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0030] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0031] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having" and any variations thereof in the description, claims and foregoing drawings of this application are intended to cover non-exclusive inclusion.

[0032] like Figures 1-3 As shown, a preferred embodiment of the present invention provides a battery casing having a first direction Z. The battery casing includes a conductive casing 1, an insulating adhesive layer 2, and an expanding adhesive layer 3.

[0033] The conductive housing 1 includes a bottom wall 11 and a side wall 12. The bottom wall 11 and the side wall 12 are connected at one end in the first direction Z to form a receiving cavity 10 for accommodating electrolyte and battery cell 100. The conductive housing 1 has an opening 13 communicating with the receiving cavity 10 at the end away from the bottom wall 11 in the first direction Z. The inner wall surface of the side wall 12 is coated with an insulating adhesive layer 2. An expanding adhesive layer 3 is coated on the side of the insulating adhesive layer 2 away from the inner wall surface of the side wall 12. The expanding adhesive layer 3 and the inner wall surface of the bottom wall 11 are spaced apart, and the expanding adhesive layer 3 and the opening 13 are spaced apart.

[0034] Based on this technical solution, by coating the inner wall surface of the side wall 12 with an insulating adhesive layer 2, when the battery cell 100 is housed in the housing cavity 10, the insulating adhesive layer 2 can form an insulating barrier between the inner wall surface of the side wall 12 and the positive electrode of the battery cell 100, thereby reducing the risk of accidental contact between the conductive housing 1 and the positive electrode of the battery cell 100 at the positive terminal and reducing the risk of internal short circuit of the battery.

[0035] By providing an expanding adhesive layer 3 on the side of the insulating adhesive layer 2 away from the side wall 12, after the electrolyte is injected into the receiving cavity 10 containing the battery cell 100, the expanding adhesive layer 3 will expand in volume after absorbing the electrolyte and fill the gap between the outer wall surface of the battery cell 100 and the inner wall surface of the side wall 12, so as to firmly fix the battery cell 100 in the receiving cavity 10. When the battery encounters severe vibration, rolling or other conditions, the expansion adhesive layer 3 can fix the battery cell 100, which can limit the shaking of the battery cell 100 in the receiving cavity 10, avoid the shaking of the battery cell 100 from generating a pulling force on the electrode tab welding joint, prevent the electrode tab from being torn or poorly welded, thereby stabilizing the internal resistance of the battery cell 100 and improving the overall reliability of the battery.

[0036] By keeping the expansion adhesive layer 3 and the inner wall surface of the bottom wall 11 and the opening 13 spaced apart, space can be reserved in the receiving cavity 10 to store the gas generated by the battery cell 100 during use, thus avoiding the current interruption device of the battery being triggered due to excessive gas in the receiving cavity 10.

[0037] It is understandable that the inner wall surface of the side wall 12 is coated with insulating adhesive layer 2, which means that all positions of the inner wall surface of the side wall 12 are coated with insulating adhesive layer 2, that is, all places of the inner wall surface of the conductive shell 1 except the inner wall surface of the bottom wall 11 are coated with insulating adhesive layer 2.

[0038] The material of the insulating adhesive layer 2 can be one or more of PET (polyethylene terephthalate), PCV (polyvinyl chloride), PTFE (polytetrafluoroethylene), and rubber, including but not limited to PET (polyethylene terephthalate), PCV (polyvinyl chloride), PTFE (polytetrafluoroethylene), and rubber. After the insulating adhesive layer 2 is coated on the inner wall surface of the side wall 12 to form an adhesive layer, the tensile elongation is 5%-20%.

[0039] The expanding adhesive layer 3 is configured to expand in volume after absorbing electrolyte.

[0040] The material of the expanding adhesive layer 3 can be one or more of polyacrylic acid, polyacrylamide, and polyacrylate, including but not limited to polyacrylic acid, polyacrylamide, and polyacrylate resin. After absorbing liquid and expanding, the volume of the expanding adhesive layer 3 increases by 10%-200%.

[0041] In this embodiment, the conductive housing 1 is a cylindrical housing.

[0042] In some other embodiments, the conductive housing 1 may also be a square housing, a prismatic housing, etc.

[0043] In this embodiment, the conductive housing 1 is a steel housing. The steel housing is a steel housing of conventional technology.

[0044] In some other embodiments, aluminum shells, aluminum alloy shells, titanium alloy shells, etc., which are conventional technologies, can also be used as conductive shells 1.

[0045] Optionally, the number of expanding adhesive layers 3 can be one or more.

[0046] Preferably, there are multiple expanding adhesive layers 3, which are spaced apart along the first direction Z. By using multiple spaced expanding adhesive layers 3, the battery cell 100 can be supported and fixed from multiple positions, enhancing the stability of the battery cell 100. By using multiple expanding adhesive layers 3 spaced apart along the first direction Z, the spacing and distribution of the multiple expanding adhesive layers 3 can be flexibly adjusted according to the structural characteristics of the battery cell 100 and the internal layout requirements of the battery. This allows for more rational use of the internal space of the battery. While ensuring that the expanding adhesive layers 3 can stably fix the battery cell 100, it avoids unnecessary space occupation within the receiving cavity 10 due to a single expanding adhesive layer being too thick or too large. This achieves optimized configuration of the internal space of the battery, providing more reasonable arrangement space for components such as the battery cell 100 and electrolyte, helping to maintain good electrochemical performance of the battery and improve the energy density and overall performance of the battery. At the same time, this arrangement also facilitates adjustment and optimization according to the needs of different specifications and types of batteries, enhancing the versatility and adaptability of the battery casing structure and expanding the application range of the battery casing.

[0047] See Figure 2 In this embodiment, there are three expanding adhesive layers 3. The three expanding adhesive layers 3 include a first expanding adhesive layer 3, a second expanding adhesive layer 3 and a third expanding adhesive layer 3. The first expanding adhesive layer 3, the second expanding adhesive layer 3 and the third expanding adhesive layer 3 are spaced apart along the first direction Z, and the second expanding adhesive layer 3 is located between the first expanding adhesive layer 3 and the third expanding adhesive layer 3.

[0048] Along the first direction Z, the size of the receiving cavity 10 is Hmm, and the size of the first expanding adhesive layer 3 is K1mm, satisfying: 0.05Hmm≤K1≤0.15Hmm.

[0049] The second expanding adhesive layer 3 has a size of K2mm, which satisfies the condition: 0.05Hmm≤K2≤0.15Hmm.

[0050] The third expanding adhesive layer 3 has a size of K3mm, which satisfies the condition: 0.05Hmm≤K3≤0.15Hmm.

[0051] By limiting the relationship between the width K of the expanding adhesive layer 3 and the depth H of the receiving cavity 10 to the range of 0.05Hmm≤K≤0.15Hmm, while ensuring that the expanding adhesive layer 3 can fix the battery cell 100, the space occupied by the expanding adhesive layer 3 between the conductive shell 1 and the battery cell 100 can be reasonably controlled. This allows sufficient space to be reserved in the receiving cavity 10 for storing the gas generated by the battery cell 100 during use, thus better preventing the current interruption device of the battery from being triggered due to excessive gas in the receiving cavity 10. The expanding adhesive layer 3 can expand and perform its function by absorbing an appropriate amount of electrolyte. If it absorbs too much, it may affect the normal distribution of electrolyte in the battery cell 100, thereby affecting the ion transport efficiency and battery capacity. By limiting the relationship between the width K of the expanding adhesive layer 3 and the depth H of the receiving cavity 10 to the range of 0.05Hmm≤K≤0.15Hmm, the amount of liquid absorbed by the expanding adhesive layer 3 can be limited, avoiding the degradation of battery performance caused by excessive liquid absorption.

[0052] Optionally, any two of K1, K2, and K3 can be equal or unequal.

[0053] In this embodiment, K1 = 0.1Hmm.

[0054] In other implementations, K1 can also be any value such as 0.06H, 0.07H, 0.08H, 0.09H, 0.11H, 0.12H, 0.13H, 0.14H that satisfies 0.05Hmm≤K1≤0.15Hmm.

[0055] In this embodiment, K2 = 0.1Hmm.

[0056] In some other implementations, K2 can also be any value such as 0.06H, 0.07H, 0.08H, 0.09H, 0.11H, 0.12H, 0.13H, 0.14H that satisfies 0.05Hmm≤K1≤0.15Hmm.

[0057] In this embodiment, K3 = 0.1Hmm.

[0058] In some other implementations, K3 can also be any value such as 0.06H, 0.07H, 0.08H, 0.09H, 0.11H, 0.12H, 0.13H, 0.14H that satisfies 0.05Hmm≤K1≤0.15Hmm.

[0059] Along the first direction Z, the distance between the first expanding adhesive layer 3 and the inner wall surface of the bottom wall 11 is L1mm.

[0060] Preferably, 0.15H ≤ L1 ≤ 0.25H. By limiting the distance between the first expanding adhesive layer 3 and the inner wall surface of the bottom wall 11 to 0.15H ≤ L1 ≤ 0.25H, while ensuring that the first expanding adhesive layer 3 can fix the battery cell 100, a suitable bottom space is reserved for the receiving cavity 10. The bottom space can be used to store the gas generated in the early stage of gas generation of the battery cell 100, avoiding the accumulation of gas at the bottom of the receiving cavity 10 and causing excessive pressure. At the same time, it also provides space for the reasonable distribution and flow of electrolyte at the bottom of the battery.

[0061] L1 can be any value that satisfies 0.15H≤L1≤0.25H, such as 0.15H, 0.16H, 0.17H, 0.18H, 0.18H, 0.20H, 0.21H, 0.22H, 0.23H, 0.24H, 0.25H, etc.

[0062] In this embodiment, L1 = 0.15H. That is, along the first direction Z, the distance between the center of the first expanding adhesive layer 3 and the inner wall surface of the bottom wall 11 is 0.2H.

[0063] Along the first direction Z, the distance between the second expanding adhesive layer 3 and the inner wall surface of the bottom wall 11 is L2mm.

[0064] Preferably, 0.45H ≤ L2 ≤ 0.55H. When the battery encounters severe vibration, rolling, or other operating conditions, the central region of the receiving cavity 10 along the first direction Z is one of the areas where the battery casing is most stressed and most affected by vibration. By limiting the distance L2 between the second expanding adhesive layer 3 and the inner wall surface of the bottom wall 11 to 0.45H ≤ L2 ≤ 0.55H, the second expanding adhesive layer 3 can be positioned in the central region of the receiving cavity 10 along the first direction Z. The second expanding adhesive layer 3 can provide sufficient support and buffering for the battery cell 100 in the central region of the receiving cavity 10, thus better securing the battery cell 100 within the receiving cavity 10.

[0065] L2 can be any value that satisfies 0.45H≤L2≤0.55H, such as 0.45H, 0.46H, 0.47H, 0.48H, 0.48H, 0.50H, 0.51H, 0.52H, 0.53H, 0.54H, 0.55H, etc.

[0066] In this embodiment, L2 = 0.45H, that is, along the first direction Z, the distance between the center of the second expanding adhesive layer 3 and the inner wall surface of the bottom wall 11 is 0.5H.

[0067] Along the first direction Z, the distance between the third expanding adhesive layer 3 and the inner wall surface of the bottom wall 11 is L3mm.

[0068] Preferably, 0.7H ≤ L3 ≤ 0.8H. By limiting the distance between the third expanding adhesive layer 3 and the inner wall surface of the bottom wall 11 to 0.75H ≤ L3 ≤ 0.8H, while ensuring that the third expanding adhesive layer 3 can fix the upper part of the battery cell 100, a suitable top space is reserved for the receiving cavity 10. This top space can serve as a gas discharge space, and the gas generated by the battery cell 100 during use can be discharged in an orderly manner through the discharge space and the exhaust structure located on the top of the battery, thereby better preventing the current interruption device of the battery from being triggered due to excessive gas in the receiving cavity 10.

[0069] L3 can be any value that satisfies 0.7H≤L3≤0.8H, such as 0.70H, 0.71H, 0.72H, 0.73H, 0.74H, 0.75H, 0.76H, 0.77H, 0.78H, 0.79H, 0.80H, etc.

[0070] In this embodiment, L3 = 0.75H, that is, along the first direction Z, the distance between the center of the second expanding adhesive layer 3 and the inner wall surface of the bottom wall 11 is 0.8H.

[0071] In the three expanding adhesive layers 3, by placing the first expanding adhesive layer 3 at the lower part of the receiving cavity 10, the second expanding adhesive layer 3 at the middle part of the receiving cavity 10, and the third expanding adhesive layer 3 at the upper part of the receiving cavity 10, the three expanding adhesive layers 3 can form a reasonable spatial distribution within the receiving cavity 10, providing balanced support for fixing the battery cell 100 at different height positions within the receiving cavity 10, thereby achieving a more comprehensive fixing effect and improving the overall stability of the battery cell 100 within the receiving cavity 10.

[0072] See Figure 3 The thickness of the insulating adhesive layer 2 is a μm, satisfying: 1 ≤ a ≤ 10. By controlling the thickness a of the insulating adhesive layer 2 to between 1 μm and 10 μm, the insulating adhesive layer 2 can provide stable insulation performance. It can effectively isolate the conductive shell 1 from the positive electrode of the battery cell 100, avoiding internal short circuits caused by contact between the two, while also preventing excessive occupation of the internal space of the receiving cavity 10 due to excessive thickness. This ensures that the battery cell 100 and the electrolyte have reasonable space to accommodate each other, maintaining the normal electrochemical performance of the battery.

[0073] The thickness of the expanding adhesive layer 3 is b μm, satisfying: 3 ≤ b ≤ 30. By controlling the thickness b of the expanding adhesive layer 3 between 3 μm and 30 μm, the expanding adhesive layer 3 can achieve an ideal expansion effect after absorbing the electrolyte. A thickness of not less than 3 μm ensures that the expanding adhesive layer 3 has sufficient basic volume, allowing it to fully expand after absorbing the electrolyte and tightly fill the gap between the outer wall of the cell 100 and the inner wall of the side wall 12, limiting the shaking of the cell 100 within the conductive shell 1. A thickness not exceeding 30 μm avoids the expanding adhesive layer 3 from occupying too much internal space of the battery, affecting the normal arrangement of the cell 100 and the electrolyte, ensuring that the battery maintains good electrochemical performance, and achieving a dual balance between stable support and performance guarantee for the cell 100.

[0074] See Figure 4 This utility model also provides a battery, which includes the battery casing of any of the above-mentioned components, and further includes an electrolyte, a battery cell 100, a cover plate 200, and a cap 300. The electrolyte and the battery cell 100 are contained in a receiving cavity 10. The negative electrode tab of the battery cell 100 is welded to the bottom wall 11 and electrically connected. There is a gap between the outer wall surface of the battery cell 100 and the inner wall surface of the side wall 12. The expanding adhesive layer 3 is located in the gap, and the side of the expanding adhesive layer 3 away from the insulating adhesive layer 2 is pressed against the outer wall surface of the battery cell 100. The cover plate 200 is connected to the end of the side wall 12 away from the bottom wall 11 and seals the opening 13. The cover plate 200 has a through hole communicating with the receiving cavity 10. The cap 300 passes through the through hole, and the outer wall surface of the cap 300 is connected to the hole wall of the through hole. The cover plate 200 and the cap 300 are insulated from each other. The positive electrode tab of the battery cell 100 is welded to the cap 300 and electrically connected.

[0075] After the electrolyte is injected into the receiving cavity 10, the expansion adhesive layer 3 will expand in volume after absorbing the electrolyte and fill the gap between the outer wall surface of the battery cell 100 and the inner wall surface of the side wall 12, so that the side of the expansion adhesive layer 3 away from the insulating adhesive layer 2 presses against the outer wall surface of the battery cell 100, so as to firmly fix the battery cell 100 in the receiving cavity 10.

[0076] The electrolyte and the battery cell 100 are conventional technologies.

[0077] The cover plate 200 and the cap 300 are conventional cover plates 200 and cap 300. The insulation of the cover plate 200 and the cap 300 can be achieved by, for example, by making the cover plate 200 an insulating material to make the cover plate 200 and the cap 300 directly insulated, or by providing insulating components such as insulating rubber rings or insulating coatings between the cover plate 200 and the cap 300 to make the cover plate 200 and the cap 300 indirectly insulated.

[0078] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.

Claims

1. A battery casing having a first orientation (Z), characterized in that, include: A conductive housing (1) includes a bottom wall (11) and a side wall (12). The bottom wall (11) and the side wall (12) are connected at one end in the first direction (Z). The bottom wall (11) and the side wall (12) form a receiving cavity (10). The conductive housing (1) has an opening (13) communicating with the receiving cavity (10) at the end away from the bottom wall (11) in the first direction (Z). Insulating adhesive layer (2), the inner wall surface of the sidewall (12) is coated with the insulating adhesive layer (2); An expanding adhesive layer (3) is applied to the side of the insulating adhesive layer (2) away from the inner wall surface of the sidewall (12). The expanding adhesive layer (3) and the inner wall surface of the bottom wall (11) are spaced apart. The expanding adhesive layer (3) and the opening (13) are spaced apart.

2. The battery casing according to claim 1, characterized in that, The thickness of the insulating adhesive layer (2) is a μm, which satisfies: 1≤a≤10.

3. The battery casing according to claim 1, characterized in that, The thickness of the expanded adhesive layer (3) is b μm, which satisfies: 3 ≤ b ≤ 30.

4. The battery casing according to claim 1, characterized in that, The number of the expanding adhesive layers (3) is multiple, and the multiple expanding adhesive layers (3) are spaced apart along the first direction (Z).

5. The battery casing according to claim 1, characterized in that, The number of the expanding adhesive layers (3) is three. The three expanding adhesive layers (3) include a first expanding adhesive layer (3), a second expanding adhesive layer (3) and a third expanding adhesive layer (3). The first expanding adhesive layer (3), the second expanding adhesive layer (3) and the third expanding adhesive layer (3) are spaced apart along the first direction (Z), and the second expanding adhesive layer (3) is located between the first expanding adhesive layer (3) and the third expanding adhesive layer (3). Along the first direction (Z), the size of the receiving cavity (10) is Hmm, the size of the first expanding adhesive layer (3) is K1mm, the size of the second expanding adhesive layer (3) is K2mm, and the size of the third expanding adhesive layer (3) is K3mm, satisfying: 0.05Hmm≤K1≤0.15Hmm, 0.05Hmm≤K2≤0.15Hmm, 0.05Hmm≤K3≤0.15Hmm.

6. The battery casing according to claim 5, characterized in that, K1=0.1Hmm, K2=0.1Hmm, K3=0.1Hmm.

7. The battery casing according to claim 5, characterized in that, Along the first direction (Z), the distance between the first expanding adhesive layer (3) and the inner wall surface of the bottom wall (11) is L1 mm, satisfying: 0.15H≤L1≤0.25H.

8. The battery casing according to claim 5, characterized in that, Along the first direction (Z), the distance between the second expanding adhesive layer (3) and the inner wall surface of the bottom wall (11) is L2mm, satisfying: 0.45H≤L2≤0.55H.

9. The battery casing according to claim 5, characterized in that, Along the first direction (Z), the distance between the third expanding adhesive layer (3) and the inner wall surface of the bottom wall (11) is L3mm, satisfying: 0.7H≤L3≤0.8H.

10. A battery, characterized in that, The battery casing includes any one of claims 1-9, and further includes an electrolyte, a battery cell (100), a cover plate (200), and a cap (300). The electrolyte and the battery cell (100) are contained within the receiving cavity (10). The negative electrode tab of the battery cell (100) is welded to and electrically connected to the bottom wall (11). A gap exists between the outer wall surface of the battery cell (100) and the inner wall surface of the side wall (12). The expanding adhesive layer (3) is located in the gap, and the side of the expanding adhesive layer (3) facing away from the insulating adhesive layer (2) abuts against the wall. The outer wall of the battery cell (100) is connected to the side wall (12) away from the bottom wall (11) and seals the opening (13). The cover plate (200) has a through hole that communicates with the receiving cavity (10). The cap (300) passes through the through hole and the outer wall of the cap (300) is connected to the hole wall. The cover plate (200) and the cap (300) are insulated from each other. The positive electrode tab of the battery cell (100) is welded to the cap (300) and electrically connected.

Images