Battery

Abstract

The present application discloses a battery, comprising a core pack and a housing. The housing comprises a first housing and a second housing; the first housing is internally provided with an accommodating cavity; the core pack is arranged in the accommodating cavity; the second housing blocks an opening; the first housing and / or the second housing are / is provided with an explosion-proof notch; the relief pressure of the explosion-proof notch is P, the tensile strength of the material of the housing is σb, the diameter of the first housing is D, the wall thickness of the housing is H, and the depth of the explosion-proof notch is h. When the explosion-proof notch is in a straight line, the relief pressure satisfies formula (I); and when the explosion-proof notch is in a curved line, the value of the relief pressure satisfies formula (II).

Description

Battery

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on July 25, 2023, with application number 202321977814.1. The entire contents of the above application are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of energy supply devices, and in particular to a battery. Background Art

[0003] Batteries are widely used in various fields, and the requirements for battery safety performance are becoming increasingly stringent. When a battery is exposed to high temperatures, overcharged, or short-circuited, a large amount of gas is generated inside the battery, causing the pressure inside the battery casing to rise sharply. To prevent the battery from exploding, an explosion-proof structure is typically installed on the battery casing to release the pressure and exhaust.

[0004] In the related art, there are mainly two types of explosion-proof structures on the battery shell. The first is to set a pressure relief hole on the shell and cover the pressure relief hole with an explosion-proof plate to form an explosion-proof valve; the second is to open an explosion-proof notch on the shell. The above two structures in the related art have the following defects: For the first structure, there will be a gap between the explosion-proof plate and the pressure relief hole, which affects the sealing of the battery. For the second structure, the explosion-proof notch is generally opened based on the operator's experience. When opening the explosion-proof notch, it is easy to cause the depth of the explosion-proof notch to be too large or insufficient. If the depth of the explosion-proof notch is too large, it will cause the shell to be too thin in some parts, which is easy to rupture and leak during the use of the battery; if the depth of the explosion-proof notch is insufficient, the air pressure cannot reach the pressure relief value of the explosion-proof notch, making it impossible to break through the explosion-proof notch to exhaust, so that the explosion-proof notch cannot play an explosion-proof role. SUMMARY OF THE INVENTION

[0005] The present application provides a battery to solve the above technical problems.

[0006] The present application provides a battery, comprising a core pack and an outer shell, wherein the outer shell comprises a first shell and a second shell, wherein the first shell has an accommodating cavity, an opening communicating with the accommodating cavity is formed on the first shell, the core pack is arranged in the accommodating cavity, and the second shell blocks the opening, and an explosion-proof notch is provided on the first shell and / or the second shell, the pressure relief pressure of the explosion-proof notch is P, and the tensile strength of the material of the outer shell is , the diameter of the first shell is D, the wall thickness of the shell is H, the depth of the explosion-proof notch is h, and the explosion-proof notch is linear, ; or, the explosion-proof notch is curved, . Beneficial effects

[0007] The beneficial effects of the present application are as follows: the battery provided by the present application has an explosion-proof notch on the outer shell, which is equivalent to a locally thinned area on the outer shell, so as to be used for exhaust and pressure relief when the air pressure inside the outer shell is too high, thereby preventing the battery from exploding, thereby making the battery safer. In addition, the design does not require a through hole for installing an explosion-proof valve on the outer shell, thereby improving the sealing of the battery. When designing the diameter D of the outer shell, the wall thickness H of the outer shell, and the pressure relief P of the battery, the explosion-proof notch of the battery is set according to the shape of the explosion-proof notch. When the explosion-proof notch is linear, the formula is used. Based on; when the explosion-proof notch is curved, the formula Based on this, a suitable explosion-proof notch depth h is opened on the shell. Based on the explosion-proof notch depth h, the effectiveness of the shell in the battery pack and assembly process is ensured, and the sealing effect and safety of the battery are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG1 is a cross-sectional view of a battery provided in some embodiments of the present disclosure;

[0009] FIG2 is a cross-sectional view of a first housing provided in some embodiments of the present disclosure;

[0010] FIG3 is a first structural diagram of a base plate provided in some embodiments of the present disclosure;

[0011] FIG4 is a partial cross-sectional view of a bottom plate provided in some embodiments of the present disclosure;

[0012] FIG5 is a second structural diagram of a base plate provided in some embodiments of the present disclosure;

[0013] FIG6 is a third structural diagram of a base plate provided in some embodiments of the present disclosure;

[0014] FIG7 is a second partial cross-sectional view of a base plate provided in some embodiments of the present disclosure;

[0015] FIG8 is a disassembled schematic diagram of a second housing, a pole, and a seal provided in some embodiments of the present disclosure;

[0016] FIG9 is a schematic diagram of the cooperation of the second housing seal provided by some embodiments of the present disclosure (the seal is not compressed);

[0017] FIG10 is a first schematic diagram of the coordination of a second housing, a pole, and a seal provided in some embodiments of the present disclosure;

[0018] FIG11 is a second schematic diagram of the coordination of the second shell, the pole, and the seal provided in some embodiments of the present disclosure.

[0019] Description of reference numerals:

[0020] 1. Core package; 11. First tab; 12. Second tab; 2. First housing; 21. Bottom plate; 211. Explosion-proof notch; 2111. Notch groove; 2111a. First notch groove; 2111b. Second notch groove; 2111c. Third notch groove; 2112. First inclined surface; 22. First enclosure; 221. Expanding portion; 23. Accommodating cavity; 3. Second housing; 31. Plate portion; 311. First mounting hole; 312. Limiting groove; 313. Raised portion; 32. Bending structure; 32 1. First bending portion; 322. Second bending portion; 4. Fixing block; 41. Second mounting hole; 411. Second inclined surface; 42. Third step surface; 43. First main body; 44. First convex ring; 5. Pole; 51. First step surface; 52. Second step surface; 53. Second main body; 54. Second convex ring; 55. Third convex ring; 6. Seal; 61. First sealing portion; 62. Second sealing portion; 63. Third sealing portion; 64. First extension portion; 65. Second extension portion; 7. Insulating sheet. Modes for Carrying Out the Invention

[0021] In the description of this application, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0022] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0023] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meanings.

[0024] Some embodiments of the present disclosure provide a battery having a relatively simple structure, high sealing performance, and high safety. The battery can be of various shapes, such as cylindrical, square, triangular, or irregularly shaped. For clarity, a specific embodiment of a circular battery is described in detail below.

[0025] As shown in Figures 1 to 4, the battery includes a core pack 1 and an outer shell. The outer shell includes a first shell 2 and a second shell 3. The first shell 2 has an accommodating cavity 23. The first shell 2 has an opening communicating with the accommodating cavity 23. The core pack 1 is arranged in the accommodating cavity. The second shell 3 blocks the opening. The first shell 2 and / or the second shell 3 are provided with an explosion-proof notch 211. The pressure relief pressure of the explosion-proof notch 211 is P. The tensile strength of the material of the outer shell is The diameter of the first shell 2 is D, the wall thickness of the shell is H, and the depth of the explosion-proof notch 211 is h, wherein the explosion-proof notch is linear. ; or, the explosion-proof notch is curved, .

[0026] The battery provided by the embodiment of the present disclosure has an explosion-proof notch 211 on the outer shell. The explosion-proof notch 211 is equivalent to a locally thinned area on the outer shell. It is used to release air when the internal pressure of the outer shell is too high to prevent the battery from exploding, thereby making the battery safer. This design does not require a through hole for installing an explosion-proof valve on the outer shell, thereby improving the sealing of the battery. When designing the diameter D of the outer shell, the wall thickness H of the outer shell, and the pressure relief P of the battery, the explosion-proof notch 211 of the battery is set according to the shape of the explosion-proof notch. When the explosion-proof notch is linear, the formula is used. Based on; when the explosion-proof notch is curved, the formula Based on this, a suitable explosion-proof notch 211 with a depth h is opened on the shell. Based on the depth h of the explosion-proof notch 211, the effectiveness of the shell in the battery pack and the assembly process is guaranteed, and the sealing effect and safety of the battery are improved.

[0027] Optionally, the explosion-proof notch 211 can be manufactured by mechanical turning, laser engraving, chemical etching, or mold stamping.

[0028] Specifically, as shown in Figures 3 and 4, the explosion-proof score 211 includes at least two score grooves 2111. All score grooves 2111 are arranged in a stepped manner along their depth direction, and the sum of the depths of all score grooves 2111 equals the depth h of the explosion-proof score 211. It is understood that the explosion-proof score 211 can adopt a segmented depth score, which reduces the difficulty of etching the explosion-proof score 211 on the housing. Moreover, the different depths of different score grooves can reduce the probability of leakage caused by residual depth due to assembly damage, thereby improving the sealing of the battery.

[0029] Specifically, as shown in Figure 4, along the depth direction of the explosion-proof notch 211, the depth difference between any two notches 2111 is Δh, where -0.02mm≤Δh≤0.01mm. This design further reduces the difficulty of machining by controlling the depth difference between two adjacent notches 2111, improving the stability of the pressure value of the explosion-proof notch 211. Optionally, the Δh value can be -0.02mm, -0.015mm, -0.01mm, -0.005mm, 0mm, 0.005mm, or 0.01mm, among others.

[0030] Specifically, as shown in FIG4 , the wall of the scored groove 2111 is a first inclined surface 2112. The first inclined surface 2112 is inclined from the bottom of the scored groove 2111 toward one end of the groove opening and away from the center of the explosion-proof notch 211. This allows the wall of the scored groove 2111 to serve as a transition surface, reducing stress concentration and simplifying processing. In other embodiments, the bottom and wall of the scored groove 2111 are perpendicular.

[0031] For example, the lengths of all the scored grooves gradually increase from the inside to the outside of the housing. Thus, the explosion-proof scoring grooves 211 can be arranged in a stepped pattern along the length, facilitating the processing of the explosion-proof scoring grooves 211. In this embodiment, the scoring grooves are all of equal width. In other embodiments, the widths of the scoring grooves may also vary.

[0032] In an alternative embodiment, as shown in Figures 4 and 5, the explosion-proof notch 211 is provided with three notched grooves 2111, namely a first notched groove 2111a, a second notched groove 2111b, and a third notched groove 2111c. The second notched groove 2111b is recessed at the bottom of the first notched groove 2111a, and the third notched groove 2111c is recessed at the bottom of the second notched groove 2111b. By etching the three notched grooves 2111 to different depths, three thinning zones of varying degrees of weakness are formed on the outer shell, enabling multi-stage rupture when the pressure within the outer shell is excessive.

[0033] When the battery is under extreme conditions such as high temperature, charging, and short circuit, a large amount of heat is generated inside the first shell 2. The strength of the first shell 2 with the explosion-proof notch 211 is relatively weak. When the internal pressure is high, the explosion-proof notch 211 will first crack to form a pressure relief channel, allowing the electrolyte, high-pressure gas and other substances inside the first shell 2 to be discharged from the crack, preventing the pressure in the first shell 2 from further increasing and causing the battery to explode, so that the explosion-proof notch 211 plays a safety and explosion-proof role.

[0034] For example, the bottom of the third scored groove 2111c is the weakest and is the first weak zone. The area between the groove wall of the second scored groove 2111b and the sidewall of the third scored groove 2111c is the second weak zone, and the area between the groove wall of the first scored groove 2111a and the groove wall of the second scored groove 2111b is the third weak zone. When the air pressure in the first shell 2 rises to a set level, the first weak zone will first rupture to release air. If the first weak zone cannot meet the required pressure, the second and third weak zones will rupture in sequence to release air as the air pressure in the first shell 2 continues to rise, thereby improving exhaust efficiency.

[0035] Furthermore, as shown in FIG3 , the length extension directions of the first notched groove 2111a, the second notched groove 2111b and the third notched groove 2111c are consistent. The length of the first notched groove 2111a is L1, the length of the second notched groove 2111b is L2, and the length of the third notched groove 2111c is L3. L1>L2>L3, so the three notched grooves 2111 have a gradient change along the length direction. In other words, the depth of the three notched grooves 2111 in the length direction has changed, which can improve the stability of the pressure relief.

[0036] Of course, in other embodiments, the number of notched grooves 2111 may also be two, four, or other numbers.

[0037] In another embodiment, the three scoring grooves 2111 have a gradient change along the width direction, that is, the widths of the three scoring grooves are different, or the three scoring grooves 2111 have a gradient change along both the width and length directions.

[0038] Of course, in other embodiments, the number of the notched grooves 2111 can be two, four, or other numbers, and is not limited to the above embodiment.

[0039] In another embodiment, as shown in Figures 6 and 7, the cross-section of the explosion-proof notch 211 is arc-shaped. In this design, the degree of weakness of the explosion-proof notch 211 along its depth direction gradually changes. Therefore, under extreme conditions such as high pressure, the explosion-proof notch 211 can also crack to form pressure relief channels of different areas according to the level of air pressure to effectively relieve pressure. In this embodiment, as shown in Figure 1, the explosion-proof notch 211 is set on the outer wall of the first shell 2, and the inner wall of the first shell 2 corresponding to the position of the explosion-proof notch 211 is a planar structure, so that the inner wall of the first shell 2 is not affected by the explosion-proof notch 211, so as to better install the core package 1. In addition, the space outside the first shell 2 is larger, which is convenient for the processing of the explosion-proof notch 211. Of course, in other embodiments, the explosion-proof notch 211 can be set on the inner wall of the first shell 2.

[0040] In an optional embodiment, as shown in FIG4 , the depth h of the explosion-proof notch 211 is 0.13 mm ≤ h ≤ 0.155 mm. Within this range, the battery has good explosion-proof performance. Optionally, the depth H of the explosion-proof notch 211 can be 0.13 mm, 0.135 mm, 0.14 mm, 0.145 mm, 0.15 mm, or 0.155 mm, etc.

[0041] In an optional embodiment, as shown in FIG7 , the width of the explosion-proof notch 211 is W, and 0.1 mm ≤ W ≤ 0.5 mm. When the width of the explosion-proof notch 211 is within this range, the battery has better explosion-proof performance. Optionally, the width W of the explosion-proof notch 211 can be in the range of 0.1 mm to 0.3 mm. For example, the width W of the explosion-proof notch 211 can be 0.1 mm, 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, 0.16 mm, 0.17 mm, 0.18 mm, 0.19 mm, 0.2 mm, 0.21 mm, 0.22 mm, 0.23 mm, 0.24 mm, 0.25 mm, 0.26 mm, 0.27 mm, 0.28 mm, 0.29 mm, or 0.3 mm, etc.

[0042] Optionally, as shown in FIG3 , the shape of the explosion-proof notch 211 is a straight line. In other words, the shape of the explosion-proof notch 211 is a straight line. The shape of the explosion-proof notch 211 is simple and easy to process.

[0043] Optionally, as shown in FIG5 , the explosion-proof notch 211 is curved. This shape can extend the length and area of ​​the explosion-proof notch 211 within the limited space of the first housing 2, thereby increasing the explosion-proof effect and improving the safety performance of the battery. Specifically, the curved shape of the explosion-proof notch 211 can be S-shaped, C-shaped, Z-shaped, annular, or other shapes with a certain curvature, or other irregular shapes.

[0044] Optionally, one or more explosion-proof notches 211 may be provided on the first shell 2, and the explosion-proof notches 211 may be strip-shaped or dot-shaped. When the explosion-proof notches 211 are dot-shaped, the plurality of explosion-proof notches 211 are arranged in a dot matrix.

[0045] In another embodiment, as shown in Figures 1 and 2, the first housing 2 includes a base plate 21 and a first enclosure 22 disposed around the base plate 21. The base plate 21 and the first enclosure 22 are connected to form a housing cavity 23. The explosion-proof notch 211 is provided on the base plate 21. During battery use, the base plate 21 is generally located at the bottom of the battery, making it difficult to be discovered, thereby improving the battery's aesthetics. In this embodiment, the housing cavity 23 of the first housing 2 has an opening at only one end. In this embodiment, the housing cavity 23 of the first housing 2 is provided with openings at both ends, and both openings are blocked by the second housing 3.

[0046] Specifically, as shown in Figure 6, the explosion-proof notch 211 is arc-shaped, and multiple explosion-proof notches 211 are evenly distributed in a circular pattern along the center of the bottom plate 21. This improves the explosion-proof performance of the battery and enhances its aesthetics. Optionally, the number of explosion-proof notches 211 can be two, three, four, or any other number, not limited to this embodiment.

[0047] In another optional embodiment, as shown in FIG2 , the first housing includes a base plate 21 and a first enclosure 22 disposed around the base plate 21. The base plate 21 and the first enclosure 22 are connected to form a receiving cavity 23. An explosion-proof notch 211 is disposed on the first enclosure 22. The location of the explosion-proof notch 211 can be designed according to actual needs and is not specifically limited here.

[0048] 2 , the wall thickness of the housing is H, 0.17 mm ≤ H ≤ 0.19 mm. Alternatively, the wall thickness H of the housing may be 0.17 mm, 0.171 mm, 0.172 mm, 0.173 mm, 0.174 mm, 0.175 mm, 0.176 mm, 0.177 mm, 0.178 mm, 0.179 mm, 0.18 mm, 0.181 mm, 0.182 mm, 0.183 mm, 0.184 mm, 0.185 mm, 0.186 mm, 0.187 mm, 0.188 mm, 0.189 mm, or 0.19 mm, etc.

[0049] Optionally, the pressure relief pressure P of the explosion-proof notch 211 is between 1.6 MPa≤P≤5 MPa. Optionally, the pressure relief pressure P of the explosion-proof notch 211 can be 1.6 MPa, 1.8 MPa, 2 MPa, 2.2 MPa, 2.4 MPa, 2.5 MPa, 2.6 MPa, 2.8 MPa, 30 MPa, 3.2 MPa, 3.4 MPa, 3.5 MPa, 3.6 MPa, 3.8 MPa, 4 MPa, 4.2 MPa, 4.4 MPa, 4.5 MPa, 4.6 MPa, 4.7 MPa, 4.8 MPa or 5 MPa.

[0050] Optionally, the diameter D of the outer shell is 5.5 mm ≤ D ≤ 15 mm. Optionally, the diameter D of the outer shell can be 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, 10.5 mm, 11 mm, 11.5 mm, 12 mm, 12.5 mm, 13 mm, 13.5 mm, 14 mm, 14.5 mm or 15 mm, etc.

[0051] In an optional embodiment, as shown in Figures 2 to 4, the shape of the explosion-proof notch 211 is linear, and the explosion-proof notch 211 is located in the middle of the bottom plate 21, wherein the wall thickness H of the bottom plate 21 is in the range of 0.18±0.01mm, the depth h of the explosion-proof notch 211 is in the range of 0.13-0.15mm, the width W of the explosion-proof notch 211 is in the range of 0.2-0.3mm, the relief pressure P is in the range of 1.6-2.6Mpa, and the diameter D of the outer shell is 5.5mm≤D≤15mm.

[0052] In another optional embodiment, as shown in Figures 2 to 5, the shape of the explosion-proof notch 211 is arc-shaped, and the arc angle of the explosion-proof notch 211 is 120°, and the explosion-proof notch 211 is located in the middle position of the bottom plate 21, wherein the wall thickness H of the bottom plate 21 is in the range of 0.18±0.01mm, the depth h of the explosion-proof notch 211 is in the range of 0.135-0.155mm, the width W of the explosion-proof notch 211 is in the range of 0.1-0.5mm, the relief pressure P is in the range of 2.6-5Mpa, and the diameter D of the shell is 5.5mm≤D≤15mm.

[0053] It can be seen from the data of the above embodiment that the depth and width of the explosion-proof notch 211 are determined by the thickness D of the plate and the pressure relief.

[0054] In one embodiment, as shown in Figures 1 and 8, the battery further includes a fixing block 4, a terminal 5, and a sealing member 6. The second shell 3 is penetrated by a first mounting hole 311; the fixing block 4 is arranged on a side of the second shell 3 facing away from the core package 1, the fixing block 4 includes a first main body 43, an outer wall of the first main body 43 is provided with a first protruding ring 44, and the thickness of the first main body 43 is greater than the thickness of the first protruding ring 44, and the first main body 43 is provided with a second mounting hole 41 corresponding to the first mounting hole 311; the terminal 5 is arranged on a side of the second shell 3 facing the core package 1, and the terminal 5 partially passes through the first mounting hole 311 and the second mounting hole 41 and is riveted to the first main body 43, the outer wall of the terminal 5 is spaced apart by a first step surface 51 and a second step surface 52, and an end surface of the first main body 43 facing the second shell 3 abuts against the first step surface 51; the sealing member 6 is partially sandwiched between the hole wall of the first mounting hole 311 and the outer wall of the terminal 5, and the first protruding ring 44 and the second step surface 52 are respectively pressed against the opposite side surfaces of the sealing member.

[0055] In the battery of this embodiment, the terminal 5 is riveted to the second mounting hole 41 of the fixing block 4, and the first stepped surface 51 of the terminal 5 is abutted and supported against the first main body 43 of the fixing block 4 to ensure the stability of the connection between the terminal 5 and the fixing block 4. During the riveting process, because the thickness of the first main body 43 is thicker than that of the first protruding ring 44, the local strength of the fixing block 4 at the riveted position is high, which can prevent the fixing block 4 from deforming during the riveting process. This allows the second protruding ring 54 and the second stepped surface 52 of the terminal 5 to press the seal 6 in one direction, and the hole wall of the first mounting hole 311 of the second shell 3 and the terminal 5 to press the seal 6 in another direction. By pressing the seal 6 in two directions at an angle, the sealing performance of the battery is improved. In addition, an explosion-proof notch 211 is provided on the hole wall of the first shell 2. The explosion-proof notch 211 is equivalent to a locally thinned area provided on the first shell 2. It is used to exhaust and release pressure when the air pressure inside the first shell 2 is too high, thereby preventing the battery from exploding. This makes the battery safer. This design does not require a through hole for installing an explosion-proof valve on the first shell 2, further improving the sealing of the battery.

[0056] It is understood that during the riveting process between the terminal 5 and the fixing block 4, the riveting equipment is required to squeeze the end of the terminal 5, causing it to deform and form a structure that fits the second mounting hole 41 for securement. Therefore, during riveting, the fixing block 4 is also subjected to a certain amount of force. If the overall thickness of the fixing block 4 is too thin, it will lack strength and deform. If the thickness of the fixing block 4 is too thick, it will increase the weight and volume of the battery, which does not meet the requirements of lightweight design. In this embodiment, by designing the fixing block 4 with a convex ring structure, a step structure is formed between the first convex ring 44 and the first body 43. The first body 43 is thicker than the first convex ring 44. Therefore, the strength of the first body 43 is higher, meeting the strength requirements for riveting with the terminal 5. The thin thickness of the first convex ring 44 can reduce the weight and volume of the fixing block 4. At the same time, the stepped structure of the fixing block 4 cooperates with the stepped surface of the terminal 5 to squeeze the seal 6, resulting in a compact structure and good sealing performance.

[0057] The seal 6 is a sealing ring with a body of revolution structure. This sealing ring can seal the circumference of the first mounting hole 311, achieving a good sealing effect. In this embodiment, the first protruding ring 44 and the first stepped surface 51 compress the seal 6 axially, while the wall of the first mounting hole 311 and the outer wall of the pole 5 compress the seal 6 radially. These two perpendicular compressive forces compress the seal 6, further enhancing the sealing effect of the seal 6. In other embodiments, the seal 6 can also have other shapes, such as square, irregular, or other structures.

[0058] Optionally, as shown in FIG2 , the first shell 2 can be made of steel, aluminum, copper, or other materials. The first shell 2 can serve as the outermost layer of the bare cell, allowing the first shell 2 to directly contact the core pack 1. The shape of the first shell 2 can be cylindrical, triangular, quadrangular, or other shapes, not limited to this embodiment.

[0059] Optionally, as shown in FIG1 , the core package 1 is composed of a positive electrode sheet, a negative electrode sheet, a separator, and a tab. In this embodiment, the core package 1 is a wound core package 1, referred to as a core. During the manufacturing process, the positive electrode sheet, the separator, and the electrode sheet are stacked in sequence and then wound together to form a core. In other embodiments, the core package 1 can be a laminated core package formed by stacking the positive electrode sheet, the separator, and the negative electrode sheet in sequence, or other core package structures familiar to those skilled in the art.

[0060] In one embodiment, as shown in Figures 8 and 10, at least a portion of the hole wall of the second mounting hole 41 is a second inclined surface 411. The second inclined surface 411 is inclined from adjacent to the second step surface 52 toward an end away from the second step surface 52 and away from the center of the second mounting hole 41. Therefore, the second mounting hole 41 of this design has an outward-expanding second inclined surface 411, which is conducive to the riveting fixation of the pole 5 and the fixing block 4, thereby improving the connection stability of the pole 5 and the fixing block 4.

[0061] It is understood that the second mounting hole 41 has a second inclined surface 411 in a portion of its wall, which means that the wall is the second inclined surface 411, while the remaining portion may be a straight surface, a curved surface, or a wall structure of another shape. Of course, the entire wall of the second mounting hole 41 may also be the second inclined surface 411.

[0062] Specifically, as shown in Figures 8 and 10, at least part of the second mounting hole 41 is a tapered hole. The tapered hole has a large end and a small end. The large end is located on the end face of the first main body 43 away from the second step surface 52. In other words, the second inclined surface 411 forms a tapered hole. After the pole 5 and the fixing block 4 are riveted, the end of the pole 5 forms a dovetail portion that matches the tapered hole. The dovetail portion is fixed with the tapered hole and has high stability. In this embodiment, the second mounting hole 41 includes a connected tapered hole and a straight hole. The tapered hole is located at the end of the first main body 43 away from the core package 1. It should be noted that for the large end and the small end of the tapered hole, the aperture of the large end is larger than the aperture of the small end.

[0063] In other embodiments, a countersunk groove is provided at one end of the first body 43 away from the core package 1, and the second mounting hole 41 passes through the bottom of the countersunk groove. During the riveting process, the end of the pole 5 can be extruded into a shape that matches the countersunk groove.

[0064] In another embodiment, as shown in FIG8 , the terminal 5 includes a second body 53, the outer wall of which is provided with a second protruding ring 54. The second body 53 passes through the first mounting hole 311 and is riveted to the second mounting hole 41. The end surface of the second protruding ring 54 facing the fixing block 4 is a first stepped surface 51. The outer wall of the second protruding ring 54 is provided with a third protruding ring 55, and the end surface of the second protruding ring 54 facing the fixing block 4 is a second stepped surface 52. It is understood that the terminal 5 is also a rotating body structure, wherein the diameter of the first body 43 is smaller than the diameter of the second protruding ring 54, and the diameter of the second protruding ring 54 is smaller than the diameter of the third protruding ring 55, resulting in a cross-sectional convex structure of the terminal 5. This structure of the terminal 5 cooperates with the seal 6 and the fixing block 4 to achieve a compact structure. The side of the first protruding ring 44 facing the second housing 3 is a third stepped surface 42, which, together with the second stepped surface 52, compresses the seal 6 in the axial direction. Optionally, the second body 53 , the second protruding ring 54 and the third protruding ring 55 may be integrally formed by a cold heading process.

[0065] In the riveting process of the pole 5 and the fixing block 4:

[0066] As shown in FIG10 , before riveting, the second body 53 of the pole 5 is cylindrical and is inserted into the second mounting hole 41. The end of the second body 53 is then extruded and deformed by a riveting device, as shown in FIG11 , to form a dovetail portion that fits the tapered hole.

[0067] In another embodiment, as shown in FIG8 , the seal 6 has a U-shaped cross-section and includes at least a first sealing portion 61, a second sealing portion 62, and a third sealing portion 63. The second sealing portion 62 and the third sealing portion 63 are respectively disposed at opposite ends of the first sealing portion 61. The first sealing portion 61 is sandwiched between the wall of the first mounting hole 311 and the outer wall of the pole 5 to radially compress the seal 6. The second sealing portion 62 is sandwiched between the first protruding ring 44 and the second housing 3. The third sealing portion 63 is sandwiched between the second stepped surface 52 and the second housing 3 to axially compress the seal 6, thereby forming the compressed seal structure shown in FIG2 , FIG4 , and FIG5 . The first extension portion 64 and the second extension portion 65 form a slot, into which the second housing 3 is partially inserted, to enhance the stability between the second housing 3 and the seal 6.

[0068] Further, a first extension portion 64 is provided at one end of the second sealing portion 62 away from the first sealing portion 61. The first extension portion 64 extends away from the second housing 3. A second extension portion 65 is provided at one end of the third sealing portion 63 away from the first sealing portion 61. The second extension portion 65 extends away from the second housing 3, so that the cross-section of the seal 6 is in a "Ji" shape. The shape of the seal 6 is in a compressed state, and the first extension portion 64 abuts against the outer side wall of the fixing block 4. The second extension portion 65 abuts against the outer side wall of the pole 5 to further improve the sealing performance of the battery.

[0069] In other embodiments, only the first extension portion 64 may be provided on the second sealing portion 62, or only the second extension portion 65 may be provided on the third sealing portion 63 by extension.

[0070] Optionally, the seal 6 is integrally injection-molded on the second housing 3, thereby further improving its sealing performance. As shown in FIG. 9, before the seal 6 is compressed by the second housing 3 and the fixing block 4, the seal 6 is in an "I" shape. As shown in FIG. 4, the cross-section of the seal 6 is in a "Ji" shape after being compressed.

[0071] In another embodiment, as shown in FIG. 1, the second housing 3 includes a plate body portion 31 and a bending structure 32 provided on the outer peripheral portion of the plate body portion 31. The first mounting hole 311 is provided on the plate body portion 31. The first housing 2 includes a bottom plate 21 and a first surrounding plate 22 surrounding the bottom plate 21. The bottom plate 21 and the first surrounding plate 22 are connected to form a receiving cavity 23. The bending structure 32 is fixedly connected to the inner side wall of the first surrounding plate 22. In this design, the bending structure 32 of the second housing 3 and the first surrounding plate 22 cooperate to increase the contact area between the second housing 3 and the first housing 2, so that the second housing 3 can block the opening of the receiving cavity 23, effectively isolate the heat of laser welding, and prevent the welding heat from affecting the internal structure of the battery.

[0072] Specifically, as shown in FIG. 2, a flared portion 221 is provided at one end of the first surrounding plate 22 away from the bottom plate 21. The flared portion 221 is hermetically connected to the bending structure 32 to further increase the contact area.

[0073] Specifically, as shown in FIG. 8, a limiting groove 312 is recessed on the side surface of the plate body portion 31 facing away from the core package 1. The first mounting hole 311 penetrates through the bottom of the limiting groove 312. The fixing block 4 is arranged in the limiting groove 312. The limiting groove 312 can limit the fixing block 4 and improve the stability of the fixing block 4. And a part of the fixing block 4 protrudes from the side surface of the plate body portion 31 facing away from the core package 1. This design ensures that the fixing block 4 has sufficient thickness so that the fixing block 4 has sufficient strength.

[0074] Specifically, as shown in Figure 8, the bent structure 32 includes a first bent portion 321 and a second bent portion 322. The first bent portion 321 is connected to the plate portion 31 and extends toward the interior of the battery. The second bent portion 322 is connected to the end of the first bent portion 321 away from the plate portion 31 and extends toward the exterior of the battery. The second bent portion 322 and the inner sidewall of the flared portion 221 are aligned in direction, ensuring more complete contact between the two and improving the welding quality between the second shell 3 and the first shell 2. The first bent portion 321 and the second bent portion 322 form a double-layer barrier, further reducing the impact of welding on the core pack 1.

[0075] Specifically, the end surface of the bent structure 32 away from the bottom plate 21 is flush with the side surface of the plate body 31 away from the bottom plate 21. More specifically, the end surface of the second bent portion 322 away from the first bent portion 321 is flush with the end surface of the bent structure 32 away from the bottom plate 21 and the side surface of the plate body 31 away from the bottom plate 21. This ensures a certain height difference between the end of the second bent portion 322 and the end surface of the fixing block 4, reducing the risk of short circuits caused by overlapping conductors during battery production and use, thereby improving battery safety.

[0076] Specifically, as shown in Figure 1, the core pack 1 is provided with a first tab 11. The folding structure 32 is welded to the first enclosure, and the first tab 11 is sandwiched between the folding structure 32 and the inner sidewall of the first enclosure 22. This eliminates the need for ejector pins to secure the first tab 11. This reduces the space occupied by the ejector pins within the first housing 2 during welding, allowing the core pack 1 to be larger and improving the battery's energy density. Furthermore, the first tab 11 extends from the core pack 1 to between the first housing 2 and the folding structure 32, eliminating the need for the first tab 11 to be located within the first housing 2, further improving the battery's energy density.

[0077] It can be understood that the core package 1 is provided with a first pole tab 11 and a second pole tab 12, one of the first pole tab 11 and the second pole tab 12 is a positive pole tab and the other is a negative pole tab, the first pole tab 11 is welded to the first shell 2, and the second pole tab 12 is electrically connected to the pole 5.

[0078] In another embodiment, the second shell 3 includes a plate body 31 and a second enclosure (not shown in the drawings) arranged on one side of the plate body 31. The second enclosure is connected to the first enclosure 22 and is arranged outside the first enclosure 22. Exemplarily, the second enclosure is welded to the first enclosure 22 so that the second shell 3 can be better covered outside the first shell 2, thereby improving the sealing of the battery.

[0079] In other embodiments, the second enclosure is inserted into the first enclosure 22. In other words, the first enclosure 22 is arranged outside the second enclosure, and a bending structure 32 is provided on the second enclosure.

[0080] Specifically, as shown in FIG1 , the battery further includes an insulating sheet 7 , which is disposed between the core pack 1 and the second shell 3 . The insulating sheet 7 can provide insulation to prevent the core pack 1 from being directly connected to the second shell 3 .

[0081] Optionally, the main material of the insulating sheet 7 is a mixture of PP, PE, PET, PVC or other insulating materials well known to those skilled in the art.

[0082] In one embodiment, as shown in Figure 8, the limiting groove 312 is integrally stamped by the plate body, so that a protrusion 313 is formed at the position of the limiting groove 312 on the side of the plate body adjacent to the core package 1. The limiting groove 312 is formed by the stamping process, which ensures that the thickness of each position of the second shell 3 is the same, and the protrusion 313 formed by stamping strengthens the second shell 3.

[0083] Optionally, as shown in FIG8 , the insulating sheet 7 is an insulating ring, and the insulating ring is located between the raised portion 313 and the folded structure.

[0084] In other embodiments, the shape of the insulating sheet 7 may also be square, circular, or other shapes, and is not limited to this embodiment.

[0085] As shown in Figures 1 to 11, the battery production process includes the following steps:

[0086] S10, manufacturing the second housing 3, the pole 5, the fixing block 4 and other components;

[0087] S20, forming a sealing member 6 as shown in FIG3 by injection molding around the wall of the first mounting hole 311 of the second housing 3;

[0088] S30, riveting the pole 5 and the fixing block 4 to form a cover assembly;

[0089] S40, pasting the insulating sheet 7 on the inner side of the second housing 3;

[0090] S50, making explosion-proof notches 211 on the outer surface of the first shell 2 by laser engraving;

[0091] S60: Provide a core package 1, install the core package 1 into the first shell 2, clamp the first electrode tab 11 of the core package 1 between the bent structure 32 of the second shell 3 and the flared portion 221 of the first shell 2, and connect the second electrode tab 12 of the core package 1 to the electrode 5;

[0092] S70, injecting electrolyte into the first shell 2;

[0093] S80, pressing the second shell 3 with a forming mold so that the second shell 3 is embedded in the flared portion 221 of the first shell 2, and then cutting off the portion of the first tab 11 that is exposed outside the first shell 2;

[0094] S90 , sealingly welding the first shell 2 and the second shell 3 along the flared portion 221 by circumferential laser welding to form the battery provided by the embodiment of the present disclosure.

[0095] The technical principles of the present disclosure have been described above in conjunction with specific embodiments. These descriptions are intended solely to illustrate the principles of the present disclosure and should not be construed in any way as limiting the scope of protection of the present disclosure. Based on the explanations herein, those skilled in the art will be able to devise other specific implementations of the present disclosure without inventive effort, and such implementations will fall within the scope of protection of the present disclosure.

Claims

1. A battery, comprising a core pack (1) and an outer shell, the outer shell comprising a first shell (2) and a second shell (3), the first shell (2) having a receiving cavity (23), the first shell (2) having an opening communicating with the receiving cavity (23), the core pack (1) being arranged in the receiving cavity (23), the second shell (3) blocking the opening, the first shell (2) and / or the second shell (3) being provided with an explosion-proof notch (211), the pressure relief of the explosion-proof notch (211) being P, and the material tensile strength of the outer shell being , the diameter of the first shell (2) is D, the wall thickness of the shell is H, and the depth of the explosion-proof notch (211) is h; The explosion-proof notch (211) is in a straight line shape. ;or, The explosion-proof notch (211) is in a curved shape. 。 2. The battery according to claim 1, wherein The explosion-proof notch (211) comprises at least two notch grooves (2111), all of the notch grooves (2111) are arranged in a stepped manner along their depth direction, and the sum of the depths of all of the notch grooves (2111) is equal to a depth h of the explosion-proof notch (211).

3. The battery according to claim 2, wherein Along the depth direction of the explosion-proof notches (211), the depth difference between any two notch grooves (2111) is △h, where -0.02mm≤△h≤0.01mm.

4. The battery according to claim 2, wherein The groove wall of the notched groove (2111) is a first inclined surface (2112), and the first inclined surface (2112) is arranged obliquely from the groove bottom of the notched groove (2111) toward one end of the notch and away from the center of the explosion-proof notch (211).

5. The battery according to claim 2, wherein From the inside to the outside of the shell, the lengths of all the notched grooves (2111) gradually increase.

6. The battery according to claim 1, wherein The depth h of the explosion-proof notch (211) is 0.13 mm ≤ h ≤ 0.155 mm; and / or, The width of the explosion-proof notch (211) is W, 0.1 mm ≤ W ≤ 0.5 mm; and / or, The release pressure P of the explosion-proof notch (211) is 1.6 MPa≤P≤5 MPa; and / or, The wall thickness H of the shell is 0.17 mm ≤ H ≤ 0.19 mm; The diameter D of the shell is 5.5 mm ≤ D ≤ 15 mm.

7. The battery according to claim 1, wherein The explosion-proof notch (211) has an arc-shaped cross section; and / or, The explosion-proof notch (211) is arranged on the outer side wall of the first shell (2), and the position of the inner side wall of the first shell (2) corresponding to the explosion-proof notch (211) is a planar structure.

8. The battery according to claim 1, wherein The first shell (2) comprises a bottom plate (21) and a first enclosure plate (22) arranged around the bottom plate (21), the bottom plate (21) and the first enclosure plate (22) being connected to form the accommodating cavity (23), and the explosion-proof notch (211) being arranged on the bottom plate (21).

9. The battery according to claim 8, wherein The explosion-proof notches (211) are arc-shaped, and the plurality of explosion-proof notches (211) are evenly distributed in a ring shape along the center of the bottom plate (21).

10. The battery according to claim 1, wherein The first shell (2) comprises a bottom plate (21) and a first enclosure (22) arranged around the bottom plate (21), the bottom plate (21) and the first enclosure (22) being connected to form the accommodating cavity (23), and the explosion-proof notch (211) being arranged on the first enclosure (22).

11. The battery according to any one of claims 1 to 10, wherein The battery further comprises a fixing block (4), a pole (5) and a sealing member (6); The second shell (3) is provided with a first mounting hole (311) running through it; The fixing block (4) is arranged on a side of the second shell (3) facing away from the core package (1), the fixing block (4) comprises a first main body (43), an outer side wall of the first main body (43) is provided with a first convex ring (44), the thickness of the first main body (43) is greater than the thickness of the first convex ring (44), and the first main body (43) is provided with a second mounting hole (41) corresponding to the first mounting hole (311); The pole (4) is arranged on a side surface of the second shell (5) facing the core package (1), and a portion of the pole (4) passes through the first mounting hole (311) and the second mounting hole (41) and is riveted to the first main body (43), an outer side wall of the pole (5) is provided with a first step surface (51) and a second step surface (52) at intervals, and an end surface of the first main body (43) facing the second shell (2) abuts against the first step surface (51); The sealing member (6) is partially sandwiched between the hole wall of the first mounting hole (311) and the outer side wall of the pole (5), and the first convex ring (44) and the second step surface (52) are respectively pressed against two opposite side surfaces of the sealing member (6).

12. The battery according to claim 11, wherein At least a portion of the hole wall of the second mounting hole (41) is a second inclined surface (411), and the second inclined surface (411) is arranged obliquely from an end adjacent to the second step surface (52) toward an end away from the second step surface (52) and away from the center of the second mounting hole (41).

13. The battery according to claim 12, wherein: At least a portion of the second mounting hole (41) is a tapered hole, the tapered hole having a large end and a small end, the large end being located on the end surface of the first body (43) away from the second step surface (52).

14. The battery according to claim 11, wherein The pole (5) comprises a second main body (53), an outer side wall of the second main body (53) is provided with a second convex ring (54), an end face of the second convex ring (54) facing the fixing block (4) is the first step face (51), an outer side wall of the second convex ring (54) is provided with a third convex ring (55), and an end face of the second convex ring (54) facing the fixing block (4) is the second step face (52).

15. The battery according to claim 11, wherein The sealing member (6) comprises at least a first sealing portion (61), a second sealing portion (62) and a third sealing portion (63); the second sealing portion (62) and the third sealing portion (63) are respectively arranged at opposite ends of the first sealing portion (61); the first sealing portion (61) is sandwiched between the hole wall of the first mounting hole (311) and the outer side wall of the pole (5); the second sealing portion (62) is sandwiched between the first convex ring (44) and the second shell (3); and the third sealing portion (63) is sandwiched between the second step surface (52) and the second shell (3).

16. The battery according to claim 15, wherein A first extending portion (64) is provided at one end of the second sealing portion (62) away from the first sealing portion (61), the first extending portion (64) extending away from the second shell (3), the first extending portion (64) abutting against an outer side wall of the fixing block (4); and / or, A second extension portion (65) is provided at one end of the third sealing portion (63) away from the first sealing portion (61), the second extension portion (65) extending away from the second shell (3), and the second extension portion (65) abutting against the outer side wall of the pole (5).

17. The battery according to claim 11, wherein The second shell (3) comprises a plate body (31) and a bending structure (32) arranged on the outer periphery of the plate body (31); the first mounting hole (311) is arranged on the plate body (31); the first shell (2) comprises a bottom plate (21) and a first enclosure (22) arranged around the bottom plate (21); the bottom plate (21) and the first enclosure (22) are connected to form the accommodating cavity (23); and the bending structure (32) is fixedly connected to the inner side wall of the first enclosure (22).

18. The battery according to claim 17, wherein A limiting groove (312) is recessed on a side surface of the plate body (31) facing away from the core package (1); the first mounting hole (311) passes through the bottom of the limiting groove (312); the fixing block (4) is arranged in the limiting groove (312); and a portion of the fixing block (4) protrudes from a side surface of the plate body (31) facing away from the core package (1).

19. The battery according to claim 18, wherein An end surface of the bending structure (32) away from the bottom plate (21) is arranged flush with a side surface of the plate body (31) away from the bottom plate (21).

20. The battery according to claim 17, wherein The core package (1) is provided with a first pole lug (11), the bending structure (32) is fixed to the first enclosure (22) by welding, and the first pole lug (11) is sandwiched between the bending structure (32) and the inner side wall of the first enclosure (22).

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