An explosion-proof valve mounting structure and an electric core

Abstract

This invention belongs to the field of battery technology, specifically disclosing an explosion-proof valve mounting structure and a battery cell. In this explosion-proof valve mounting structure, a mounting plate has a protrusion facing the electrode assembly. A fixing component is disposed in a receiving groove formed on the side of the protrusion away from the electrode assembly. The fixing component includes a connecting block and a plastic-coated part surrounding the connecting block. A first mounting groove is provided on the side of the connecting block near the electrode assembly. The circumferential edge of the explosion-proof valve is received in the first mounting groove, and a first sealing element is sandwiched between the mounting plate and the connecting block. The connecting block presses the explosion-proof valve against the first sealing element. A current-conducting terminal presses a second plastic part against the mounting plate, and the circumferential edge of the second plastic part presses the plastic-coated part against the mounting plate, thereby fixing the fixing component on the mounting plate. The explosion-proof valve and the connecting block are made of the same material, avoiding the potential difference corrosion problem between the explosion-proof valve and the connecting block. The explosion-proof valve has a stable detonation value and high safety. This invention also provides a battery cell including the above-described explosion-proof valve mounting structure.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to an explosion-proof valve mounting structure and a battery cell. Background Technology

[0002] In steel-cased battery cells, both the casing and the cover are made of stainless steel. Steel-cased cells offer high dimensional consistency after encapsulation and have strong impact resistance, effectively protecting the internal electrode assembly. Generally, an explosion-proof valve is installed on the cover to prevent explosions in the event of thermal runaway of the internal electrode assembly, thus ensuring the safety performance of the steel-cased battery cell.

[0003] Currently, one approach to manufacturing explosion-proof valves involves directly machining grooves onto the cover plate. While this ensures a high connection strength between the valve and the cover plate, its processing efficiency is low. When the cover plate is thick, etching a single valve can take several minutes or even tens of minutes, hindering mass production. Directly welding a steel explosion-proof valve to a steel cover plate avoids potential corrosion at the weld joint. However, stainless steel is very hard, making it difficult to machine steps onto the cover plate. This makes it impractical to use the same step features found in existing aluminum-cased batteries and aluminum explosion-proof valve connection structures. Furthermore, steel explosion-proof valves are difficult to machine and form, resulting in unstable detonation values ​​and potential safety hazards. Summary of the Invention

[0004] The purpose of this invention is to provide an explosion-proof valve mounting structure and battery cell that can fix the explosion-proof valve to the mounting plate and avoid the corrosion problem caused by the potential difference between the two. The explosion-proof valve has high processing precision and stable detonation value.

[0005] To achieve this objective, the present invention adopts the following technical solution: On one hand, the present invention provides an explosion-proof valve mounting structure, comprising: The mounting plate has a protrusion facing the electrode group, and the side of the protrusion away from the electrode group forms a receiving groove. The bottom of the receiving groove has a through first mounting hole. A fixing component is disposed at the receiving groove. The fixing component includes a connecting block and a plastic-coated component. The plastic-coated component wraps around the circumference of the connecting block, at least a portion of the end face of the connecting block near the electrode group, and a portion of the end face of the connecting block away from the electrode group. The plastic-coated component and the connecting block are integrally formed. A second mounting hole is provided at the center of the connecting block, and a first mounting groove is provided in the circumference of the second mounting hole near the electrode group. A first plastic component is disposed along a first direction on the side of the mounting plate near the electrode assembly; The second plastic part is disposed along the first direction on the side of the mounting plate opposite to the electrode group; A current-guiding terminal is disposed along a first direction through the first plastic part, the mounting plate and the second plastic part. The current-guiding terminal presses the first plastic part and the second plastic part against the mounting plate. The circumferential edge of the second plastic part abuts against the end face of the connecting block on the side away from the electrode group, which is wrapped by the plastic part, so as to press the fixing component against the mounting plate. An explosion-proof valve, wherein the circumferential edge of the explosion-proof valve is accommodated in the first mounting groove on the connecting block, the explosion-proof valve and the connecting block are made of the same material, and the first mounting hole and the second mounting hole can communicate after the explosion-proof valve is opened; A first sealing element is disposed along a first direction between the mounting plate and the explosion-proof valve, and between the mounting plate and the connecting block, wherein the connecting block presses the explosion-proof valve against the first sealing element.

[0006] Optionally, along the first direction, the distance between the bottom wall of the first mounting groove and the end face of the connecting block on the side opposite to the pole group is e; The value of e is in the range of 0.5mm≤e≤2mm.

[0007] Optionally, along the second direction, the width of the contact surface between the first seal and the connecting block is d2, and the width of the overlapping portion of the first seal, the explosion-proof valve, and the protrusion is d3. The range of values ​​for d2 is: 1mm ≤ d2 ≤ 2mm; The range of d3 is: 1mm≤d3≤2mm.

[0008] Optionally, the connecting block has a second mounting groove on the end face opposite to the electrode group. The second mounting groove is located in the circumferential direction of the connecting block. The plastic-coated part includes a first horizontal part, a vertical part, and a second horizontal part. The first horizontal part wraps around a portion of the end face of the connecting block near the electrode group. The vertical part wraps around the circumferential direction of the connecting block and is spaced apart from the sidewall of the receiving groove. The second horizontal part wraps around a portion of the end face of the connecting block opposite to the electrode group and is located in the second mounting groove. The second plastic part abuts against the second horizontal part in a first direction.

[0009] Optionally, along the first direction, the distance between the bottom wall of the second mounting groove and the end face of the connecting block facing the pole group is c; The value of c is in the range of 0.5mm≤c≤2mm.

[0010] Optionally, the current guiding terminal includes a first plate, a second plate, and a column, wherein the second plate and the column are integrally formed; the first plate is located on the side of the first plastic part closer to the electrode group, the second plate is located on the side of the second plastic part away from the electrode group, and the column passes through the second plastic part, the mounting plate, and the first plastic part before connecting to the first plate.

[0011] Optionally, along the second direction, the peripheral sidewall of the second plate is located on the side of the vertical portion closer to the center of the plastic-coated part, and the distance between the peripheral sidewall of the connecting block and the peripheral sidewall of the second plate is b; The value of b is in the range of 0.5mm ≤ b ≤ 5mm.

[0012] Optionally, the thickness of the second plate is a along the first direction; The range of values ​​for a is: 2mm ≤ a ≤ 5mm.

[0013] Optionally, the explosion-proof valve mounting structure further includes a second sealing element, which is sleeved on the outside of the column and sandwiched between the column and the mounting plate.

[0014] On the other hand, the present invention provides a battery cell including the explosion-proof valve mounting structure of any of the above-mentioned solutions.

[0015] The beneficial effects of this invention are as follows: This invention provides an explosion-proof valve mounting structure, including a mounting plate, a fixing component, a first plastic part, a second plastic part, a flow guiding terminal, an explosion-proof valve, and a first sealing element. The mounting plate has a protruding portion facing the electrode assembly, and a receiving groove is formed on the side of the protruding portion facing away from the electrode assembly. The bottom of the receiving groove has a through first mounting hole. The fixing component is disposed in the receiving groove and includes a connecting block and a plastic-coated part surrounding the connecting block. The plastic-coated part and the connecting block are integrally formed. A second mounting hole is provided at the center of the connecting block, and a first mounting groove is provided circumferentially on the side of the second mounting hole near the electrode assembly. The circumferential edge of the explosion-proof valve is received in the first mounting groove on the connecting block, and the first sealing element is disposed between the mounting plate and the connecting block along a first direction. The connecting block presses the explosion-proof valve against the first sealing element, and the first mounting hole and the second mounting hole are connected after the explosion-proof valve is opened. The flow guiding terminal presses the second plastic part against the mounting plate, and the circumferential edge of the second plastic part abuts against the portion of the plastic-coated part covering the end face of the connecting block facing away from the electrode assembly, thereby fixing the fixing component to the mounting plate. The explosion-proof valve and the connecting block are made of the same material, thus avoiding potential difference corrosion between them. The explosion-proof valve has a stable detonation value and high safety. The plastic-coated parts insulate the connecting block from the mounting plate, and the first seal insulates the explosion-proof valve from the mounting plate, thereby ensuring electrical safety.

[0016] The present invention also provides a battery cell including the aforementioned explosion-proof valve mounting structure. By employing this explosion-proof valve mounting structure, the explosion-proof valve can be fixed to the mounting plate, avoiding potential difference corrosion between the two. The explosion-proof valve has high processing precision, a stable detonation value, and the battery cell exhibits good safety performance. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0018] Figure 1 This is an exploded view of the battery cell cover plate provided in Embodiment 1 of the present invention; Figure 2 This is an exploded view of the battery cell cover plate provided in Embodiment 1 of the present invention from another perspective; Figure 3 This is a top view of the battery cell cover plate provided in an embodiment of the present invention; Figure 4 yes Figure 3 Sectional view of section I-I; Figure 5 yes Figure 4 Enlarged view of a section at point II; Figure 6 This is a schematic diagram of the battery cell structure provided in Embodiment 1 of the present invention; Figure 7 This is a schematic diagram of the battery cell structure provided in Embodiment 2 of the present invention.

[0019] In the picture: 100. Cell cover plate; 110. Cover plate body; 111. Protrusion; 1111. Receiving groove; 1112. First mounting hole; 112. First through hole; 120. Fixing component; 121. Connecting block; 1211. Second mounting hole; 1212. First mounting groove; 1213. Second mounting groove; 122. Plastic-coated part; 1221. First horizontal part; 1222. Vertical part; 1223. Second horizontal part; 130. First plastic part; 131. Third mounting hole; 132. Second 140. Through hole; 141. Second plastic part; 142. Third through hole; 142. Limiting plate; 150. Flow guide terminal; 151. First plate; 1511. Fourth through hole; 152. Second plate; 153. Column; 160. Explosion-proof valve; 161. Fixing part; 162. Body part; 1621. Scoring groove; 1622. Opening part; 170. First sealing element; 171. First sealing part; 172. Second sealing part; 180. Second sealing element; 200. Housing; 201. Opening. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0021] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" 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 invention based on the specific circumstances.

[0022] 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.

[0023] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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 the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0024] Example 1 like Figures 1-5 As shown, this embodiment provides an explosion-proof valve mounting structure, which includes a mounting plate, a fixing component 120, a first plastic part 130, a second plastic part 140, a flow guiding terminal 150, a first sealing element 170, and an explosion-proof valve 160. The mounting plate is one of the walls of the battery cell's outer casing, and the electrode group (not shown in the figure) is disposed within the casing. In this embodiment, the mounting plate is exemplified by the cover plate body 110 in the battery cell cover plate 100; the cover plate body 110 in the following description refers to the mounting plate.

[0025] Specifically, the first plastic part 130, the cover plate body 110, and the second plastic part 140 are stacked sequentially along a first direction. The first plastic part 130 is disposed along the first direction on the side of the cover plate body 110 near the electrode group, and the second plastic part 140 is disposed along the first direction on the side of the cover plate body 110 away from the electrode group. A current-conducting terminal 150 passes through the first plastic part 130, the cover plate body 110, and the second plastic part 140 along the first direction, pressing the first plastic part 130 and the second plastic part 140 tightly onto the cover plate body 110, and fixing the current-conducting terminal 150 to the cover plate body 110. The aforementioned first direction is... Figure 1 The X-axis direction shown is also the thickness direction of the cover plate body 110. A protrusion 111 is provided on the cover plate body 110 in the direction facing the pole group. A receiving groove 1111 is formed on the side of the protrusion 111 away from the pole group. The fixing component 120 is disposed at the receiving groove 1111.

[0026] The fixing component 120 includes a connecting block 121 and a plastic-coated component 122. The plastic-coated component 122 covers the circumference of the connecting block 121, at least a portion of the end face of the connecting block 121 near the electrode group, and a portion of the end face of the connecting block 121 away from the electrode group. The plastic-coated component 122 and the connecting block 121 are integrated into a single structure through injection molding. The bottom of the receiving groove 1111 on the cover plate body 110 is provided with a through first mounting hole 1112, and the center of the connecting block 121 is provided with a second mounting hole 1211. The first mounting hole 1112 and the second mounting hole 1211 are coaxially arranged and interconnected. The first plastic component 130 is provided with a third mounting hole 131, and the protrusion 111 on the cover plate body 110 passes through the third mounting hole 131 and is accommodated within the third mounting hole 131. The connecting block 121 has a second mounting hole 1211 on its circumferential side near the electrode assembly, and the circumferential edge of the explosion-proof valve 160 is accommodated in the first mounting groove 1212 on the connecting block 121. A first sealing element 170 is disposed along a first direction between the cover plate body 110 and the explosion-proof valve 160, and between the cover plate body 110 and the connecting block 121. The circumferential edge of the second plastic part 140 abuts against the end face of the connecting block 121 on the side away from the electrode assembly, which is covered by the plastic-coated part 122, to press the fixing assembly 120 tightly against the cover plate body 110. The connecting block 121 of the fixing assembly 120 presses the circumferential edge of the explosion-proof valve 160 against the first sealing element 170, thereby realizing the installation of the explosion-proof valve 160 on the cover plate body 110. Part of the connecting block 121 is directly pressed against the first sealing element 170 to ensure good sealing at the installation location of the explosion-proof valve 160. In this embodiment, the installation of the explosion-proof valve 160 and the fixing component 120 on the cover plate body 110 does not require welding. After the second plastic part 140 is fixed to the cover plate body 110 through the flow guiding terminal 150, the second plastic part 140 can limit the fixing component 120, preventing it from detaching from the cover plate body 110. Furthermore, the fixing component 120 limits the explosion-proof valve 160, pressing it firmly onto the cover plate body 110. Moreover, the plastic-coated part 122 and the first sealing part 170 can insulate and isolate the connecting block 121 and the explosion-proof valve 160 from the cover plate body 110, avoiding electrochemical corrosion problems that occur when the cover plate body 110, connecting block 121, and explosion-proof valve 160 are made of different metal materials. Optionally, in this embodiment, the cover plate body 110 can be made of stainless steel, the connecting block 121 can be made of aluminum, and the plastic-coated part 122 can be made of PPS or PP.

[0027] Optionally, the explosion-proof valve 160 and the connecting block 121 are made of the same material, for example, both the explosion-proof valve 160 and the connecting block 121 are made of aluminum. The explosion-proof valve 160 made of aluminum is easy to process and manufacture, has high processing efficiency, and high processing precision, ensuring a stable detonation value for the explosion-proof valve 160, making the battery cell safer and more reliable. Furthermore, when the gas pressure inside the battery cell exceeds the detonation value of the explosion-proof valve 160, the explosion-proof valve 160 opens and forms a pressure relief channel. The first mounting hole 1112, the pressure relief channel of the explosion-proof valve 160, and the second mounting hole 1211 are sequentially connected to smoothly realize the pressure relief function of the explosion-proof valve 160. High-temperature and high-pressure gas can be discharged through the first mounting hole 1112, the pressure relief channel of the explosion-proof valve 160, and the second mounting hole 1211, avoiding the risk of battery cell explosion.

[0028] See also Figure 4 and Figure 5 Along the first direction, the distance between the bottom wall of the first mounting groove 1212 and the end face of the connecting block 121 on the side opposite to the pole group is denoted as e. The value of e ranges from 0.5mm to 2mm. For example, the value of e can be 0.5mm, 0.8mm, 1.0mm, 1.2mm, 1.5mm, 1.8mm, or 2.0mm. By limiting the value of e to the above range, on the one hand, it ensures that the mechanical strength of the connecting block 121 is still sufficient after the first mounting groove 1212 is opened, and it is not easy to deform. This provides good support for the explosion-proof valve 160 and can stably fix the explosion-proof valve 160. If the value of e is too small, the mechanical strength of the connecting block 121 near the explosion-proof valve 160 is insufficient, which can easily lead to deformation. This may cause the explosion-proof valve 160 to be squeezed or stretched, and the groove 1621 of the explosion-proof valve 160 may be deformed, leading to sealing failure. The detonation value of the explosion-proof valve 160 will be unstable, reducing its reliability. If the value of e is too large, the design redundancy will be excessive, resulting in increased material costs and wasting space in the thickness direction of the cover plate body 110.

[0029] Optionally, the explosion-proof valve 160 includes a fixing part 161 and a body part 162. The fixing part 161 is arranged circumferentially around the body part 162. The body part 162 is provided with a groove 1621, and the inner side of the groove 1621 forms an opening part 1622. After the explosion-proof valve 160 is opened, the body part 162 breaks at the groove 1621, and a pressure relief channel is formed at the opening part 1622. The groove 1621 can be a C-shaped groove or an oblong groove. The fixing part 161 is located in the first mounting groove 1212, and the end face of the fixing part 161 facing the electrode group is flush with the end face of the connecting block 121 facing the electrode group, thereby ensuring that the first sealing member 170 is uniformly compressed.

[0030] Furthermore, a second mounting groove 1213 is provided on the end face of the connecting block 121 facing away from the electrode group. The second mounting groove 1213 is located circumferentially on the connecting block 121. The plastic-coated part 122 includes a first horizontal part 1221, a vertical part 1222, and a second horizontal part 1223. The first horizontal part 1221 wraps around a portion of the end face of the connecting block 121 near the electrode group. The vertical part 1222 wraps around the circumference of the connecting block 121 and is spaced apart from the sidewall of the receiving groove 1111. The second horizontal part 1223 wraps around a portion of the end face of the connecting block 121 facing away from the electrode group and is located within the second mounting groove 1213. The second plastic part 140 abuts against the second horizontal part 1223 along a first direction. The cross-sections of the first horizontal part 1221, the vertical part 1222, and the second horizontal part 1223 form a U-shaped structure, which wraps around the connecting block 121, thereby stably connecting the plastic-coated part 122 and the connecting block 121 into an integral structure.

[0031] The first sealing element 170 includes a first sealing portion 171 and a second sealing portion 172. The first sealing portion 171 is disposed on the side of the second sealing portion 172 near its central axis and extends into the first mounting hole 1112. The inner wall of the first sealing portion 171 abuts against the wall of the first mounting hole 1112. The second sealing portion 172 is partially sandwiched between the connecting block 121 and the protrusion 111 of the cover plate body 110 along a first direction, and partially sandwiched between the circumferential edge of the explosion-proof valve 160 and the protrusion 111 of the cover plate body 110. After the second sealing portion 172 is compressed by the connecting block 121 and the explosion-proof valve 160, the thickness of the second sealing portion 172 is equal to the thickness of the first horizontal portion 1221 of the plastic-coated part 122.

[0032] Along the second direction, the width of the contact surface between the second sealing portion 172 of the first sealing member 170 and the connecting block 121 is d2, and the width of the overlapping portion of the second sealing portion 172 of the first sealing member 170, the explosion-proof valve 160, and the protrusion 111 is d3. That is, the total width of the portion of the second sealing portion 172 of the first sealing member 170 compressed by the connecting block 121 and the explosion-proof valve 160 is d2+d3, where d2+d3 is greater than 2mm. This ensures a good sealing effect for the first sealing member 170. Optionally, the range of d2 is 1mm≤d2≤2mm, and the range of d3 is 1mm≤d3≤2mm. By controlling the values ​​of d2 and d3 within the aforementioned range, the second sealing portion 172 of the first sealing element 170, after compression, can have a larger sealing width, effectively sealing the gaps between the connecting block 121 and the protrusion 111, as well as the gaps between the explosion-proof valve 160 and the protrusion 111, thus meeting the sealing grade requirements of the battery cell and saving material costs. Otherwise, if the values ​​of d2 and d3 are too small, the total width of the contact surface between the second sealing portion 172 of the first sealing element 170 and the connecting block 121 and the explosion-proof valve 160 is small, resulting in poor sealing performance and failing to meet the sealing grade requirements of the battery cell; if the values ​​of d2 and d3 are too large, there will be more design redundancy, increasing material costs.

[0033] See also Figure 5 Along the first direction, the distance between the bottom wall of the second mounting groove 1213 and the end face of the connecting block 121 facing the pole group is denoted by c, and the value of c ranges from 0.5mm to 2mm. For example, the value of c can be 0.5mm, 0.8mm, 1.0mm, 1.2mm, 1.5mm, 1.8mm, or 2.0mm. By limiting the value of c to the above range, it is ensured that the connecting block 121 still has sufficient mechanical strength after processing the second mounting groove 1213, is not prone to deformation, and can stably fix the plastic-coated part 122, resulting in good fixing effect on the cover plate body 110. If the value of c is too small, the mechanical strength of the side of the connecting block 121 near the second plastic part 140 is insufficient, and deformation is likely to occur, which may lead to the risk of the fixing component 120 falling off the cover plate body 110, reducing reliability; if the value of c is too large, there will be too much design redundancy, resulting in waste of material costs.

[0034] The current-conducting terminal 150 includes a first plate 151, a second plate 152, and a pillar 153, wherein the second plate 152 and the pillar 153 are integrally formed. The first plate 151 is located on the side of the first plastic part 130 close to the electrode group, and the second plate 152 is located on the side of the second plastic part 140 away from the electrode group. The cover plate body 110 has a first through hole 112, the first plastic part 130 has a second through hole 132, the second plastic part 140 has a third through hole 141, and the first plate body 151 has a fourth through hole 1511. The column 153 passes sequentially through the third through hole 141 on the second plastic part 140, the first through hole 112 on the cover plate body 110, the second through hole 132 on the first plastic part 130, and the fourth through hole 1511 on the first plate body 151 along a first direction. Then, the peripheral sidewall of the column 153 near the electrode group is welded to the wall of the fourth through hole 1511 on the first plate body 151. Thus, the current guiding terminal 150, the first plastic part 130, and the second plastic part 140 are fixedly installed on the cover plate body 110. Optionally, in some embodiments, the end of the column 153 near the pole group can also be riveted to the circumferential riveting groove of the fourth through hole 1511 on the first plate 151 after passing through the fourth through hole 1511, and then welded to the groove wall of the riveting groove. This connection method is more stable and reliable.

[0035] See also Figure 1 and Figure 4 The column 153 is fitted with a second sealing element 180. The second sealing element 180 is sandwiched between the outer peripheral wall of the column 153 and the wall of the first through hole 112, and between the outer peripheral wall of the column 153 and the wall of the second through hole 132. The second sealing element 180 can seal the gap between the column 153 and the cover plate body 110, and the gap between the cover plate body 110 and the first plate 151, so as to ensure good sealing between the flow guiding terminal 150 and the cover plate body 110.

[0036] Furthermore, in this embodiment, two of each of the second plastic component 140, the flow guiding terminal 150, and the second sealing component 180 are provided. The two second plastic components 140, the two flow guiding terminals 150, and the two second sealing components 180 are symmetrically arranged about the first mounting hole 1112 on the cover plate body 110. The cover plate body 110 has two first through holes 112, which are located on both sides of the first mounting hole 1112 along a second direction. The aforementioned second direction is... Figure 4The Y-axis direction shown is also the length direction of the cover plate body 110. The first plastic part 130 has two second through holes 132, located on both sides of the third mounting hole 131 along the second direction. Each second plastic part 140 has a third through hole 141, and each first plate 151 has a fourth through hole 1511. The column 153 of each flow-guiding terminal 150 passes through the third through hole 141 of a second plastic part 140, the first through hole 112 of a cover plate body 110, the second through hole 132 of a first plastic part 130, and the fourth through hole 1511 of a first plate 151. Each column 153 is fitted with a second sealing member 180. By setting two second plastic parts 140 to respectively press the plastic-coated part 122 in the fixing assembly 120 along the second direction on both sides, the forces on both ends of the fixing assembly 120 along the second direction are balanced, thus ensuring that it can be stably pressed onto the cover plate body 110.

[0037] See also Figure 5 The second plastic part 140 is provided with a limiting plate 142 in its circumferential direction. The limiting plate 142 and the second plastic part 140 form a limiting groove, and the second plate body 152 is at least partially accommodated in the limiting groove. The setting of the limiting plate 142 helps to improve the positioning accuracy between the flow guiding terminal 150 and the second plastic part 140, resulting in a higher assembly yield. Furthermore, along the second direction, the peripheral sidewall of the second plate body 152 is located on the side of the vertical part 1222 close to the center of the plastic-coated part 122, thereby ensuring that the second plastic part 140 can press against the second horizontal part 1223 of the plastic-coated part 122, thus making the fixing assembly 120 more stable and securely fixed on the cover plate body 110.

[0038] Optionally, along the second direction, the distance between the peripheral sidewall of the connecting block 121 and the peripheral sidewall of the second plate 152 is b, and the value of b is in the range of 0.5mm ≤ b ≤ 5mm. For example, the value of b can be 0.5mm, 0.8mm, 1.0mm, 2.0mm, 3.0mm, 4.0mm, or 5.0mm, etc. By limiting the value of b to the above range, the width of the contact surface between the second plastic part 140 and the plastic-coated part 122 is ensured to be large, which can stably press and fix the fixing component 120 onto the cover plate body 110. If the value of b is too small, the width of the contact surface between the second plastic part 140 and the plastic-coated part 122 is too narrow, and the fixing component 120 is easy to fall off the cover plate body 110, resulting in poor reliability; if the value of b is too large, there will be too much design redundancy, resulting in a waste of material costs and space.

[0039] Optionally, along the first direction, the thickness of the second plate 152 is 'a', and the value of 'a' ranges from 2mm to 5mm. For example, the value of 'a' can be 2.0mm, 3.0mm, 4.0mm, or 5.0mm, etc. By limiting the value of 'a' to the above range, on the one hand, the mechanical strength of the second plate 152 is ensured to be sufficiently high, making it less prone to deformation, and the second plastic part 140 can be stably pressed and fixed on the cover plate body 110, thereby enabling the second plastic part 140 to press and fix the assembly 120; on the other hand, the heat generated when the second plate 152 is welded to the conductive busbar (a conductive structure that electrically connects two adjacent battery cells) is avoided from causing the second plastic part 140 to deform. If the value of a is too small, the mechanical strength of the second plate 152 is insufficient, and deformation is likely to occur. The circumferential edge of the second plastic part 140 is prone to warping, which weakens the clamping effect on the fixing component 120. The fixing component 120 is at risk of falling off the cover plate body 110, reducing reliability. If the value of a is too large, there will be too much design redundancy, resulting in a waste of material costs and wasting space in the thickness direction of the cover plate body 110.

[0040] Along the first direction, the thickness of the protrusion 111 on the cover body 110 located circumferentially to the first mounting hole 1112 is f, and the value of f is in the range of 0.8mm ≤ f ≤ 2mm. For example, the value of f can be 0.8mm, 1.0mm, 1.2mm, 1.5mm, 1.8mm, or 2.0mm, etc. By limiting the value of f to the above range, the protrusion 111 is guaranteed to have sufficient mechanical strength, is not prone to deformation, and can stably support and fix the fixing component 120, thereby ensuring a good fixing effect of the explosion-proof valve 160 on the cover body 110. If the value of f is too small, the mechanical strength of the protrusion 111 is insufficient, and it is prone to deformation, resulting in poor support effect for the fixing component 120. The fixing component 120 is at risk of displacement or detachment, reducing reliability. If the value of f is too large, there is too much design redundancy, resulting in waste of material costs and wasting space in the thickness direction of the cover body 110.

[0041] See Figure 6This embodiment also provides a battery cell, including a housing and the aforementioned explosion-proof valve mounting structure. The housing includes a shell 200 and two cover plate bodies 110. The shell 200 has an opening 201 at each end along a first direction. The two cover plate bodies 110 are respectively connected to one opening 201 of the shell 200, forming a closed space for mounting the electrode assembly. One of the cover plate bodies 110 is a mounting plate, and the cover plate body 110 is connected to the explosion-proof valve 160 using the aforementioned explosion-proof valve mounting structure. By using the explosion-proof valve mounting structure in this embodiment, the explosion-proof valve 160 made of aluminum can be fixed to the cover plate body 110 made of steel, avoiding potential difference corrosion between the two. The explosion-proof valve 160 has high processing precision, a stable detonation value, and good safety performance of the battery cell.

[0042] Of course, in other embodiments, one sidewall of the housing 200 can also be connected to the explosion-proof valve 160 using the aforementioned explosion-proof valve mounting structure. That is, one sidewall of the housing 200 can also serve as a mounting plate for the explosion-proof valve 160.

[0043] The following uses samples from specific implementation cases to verify the relevant dimensional design of the explosion-proof valve installation structure in the above-mentioned battery cell. For details, please refer to Table 1.

[0044] Table 1 As can be seen from the above results, the values ​​of parameters b, c, d2, and d3 in Examples 1 to 5 all meet their corresponding size limitations. The sealing effect at the first mounting hole 1112 on the cover plate body 110 is good, and it can still pass the helium test after a long period of use, with a long service life. The explosion-proof valve 160 has a stable detonation value, high reliability, and good product quality.

[0045] In Comparative Example 1, the value of parameter b is less than the minimum value within its range of 0.5mm ≤ b ≤ 5mm. At this time, the clamping effect of the second plastic part 140 on the fixing component 120 is poor, and the fixing component 120 cannot stably cooperate with the protrusion 111 on the cover plate body 110. Immediately after assembly, the sealing effect at the first mounting hole 1112 on the cover plate body 110 is good, but after prolonged use, there is an air leakage problem between the fixing component 120 and the cover plate body 110, failing the helium test and posing a risk of airtightness failure, resulting in a short service life. The detonation value of the explosion-proof valve 160 is unstable and inconsistent, indicating a defective product.

[0046] In Comparative Example 2, the value of parameter c is less than the minimum value of its range of 0.5mm ≤ c ≤ 2mm. At this time, the mechanical strength of the connecting block 121 near the second plastic part 140 is insufficient, and deformation is prone to occur. Consequently, the fixing effect of the fixing component 120 on the cover plate body 110 is poor, a certain proportion of the battery cells fail the helium test, the sealing effect at the first mounting hole 1112 on the cover plate body 110 is poor, and the detonation value of the explosion-proof valve 160 is unstable and inconsistent, resulting in product defects.

[0047] In Comparative Example 3, the value of parameter d2 is less than the minimum value within its range of 1mm ≤ d2 ≤ 2mm. The width of the second sealing part 172 of the first sealing element 170 compressed by the connecting block 121 is small, the sealing distance is short, and the sealing performance is poor. A certain proportion of the battery cells cannot pass the helium test. The sealing effect at the first mounting hole 1112 on the cover plate body 110 is not good. Moreover, the detonation value of the explosion-proof valve 160 is unstable and inconsistent, resulting in product defects.

[0048] In Comparative Example 4, the value of parameter d3 is less than the minimum value within its range of 1mm ≤ d3 ≤ 2mm. The width of the second sealing part 172 of the first sealing element 170 compressed by the explosion-proof valve 160 is small, the sealing distance is short, and the sealing performance is poor. A certain proportion of the battery cells cannot pass the helium test. The sealing effect at the first mounting hole 1112 on the cover plate body 110 is not good. Moreover, the detonation value of the explosion-proof valve 160 is unstable and inconsistent, resulting in product defects.

[0049] Taking all factors into consideration, when the dimensions of the battery cell (b, c, d2, d3) all meet the above-mentioned dimensional requirements, the battery cell can be guaranteed to have good sealing performance and can be used for a long time without leakage. The explosion-proof valve 160 has a stable detonation value, high reliability, and the battery cell product is of good quality.

[0050] Example 2 This embodiment provides a battery cell, which differs from the battery cell in Embodiment 1 in that the structure of the outer casing is different.

[0051] Specifically, see Figure 7 In this embodiment, the outer casing of the battery cell includes a housing 200 and a cover plate body 110. The housing 200 has an opening 201 at one end along a first direction. The cover plate body 110 is connected to the opening 201 of the housing 200, forming a closed space for mounting the electrode assembly. The cover plate body 110 serves as a mounting plate, and it is connected to the explosion-proof valve 160 using the aforementioned explosion-proof valve mounting structure. By employing the explosion-proof valve mounting structure in this embodiment, the explosion-proof valve 160 made of aluminum can be fixed to the cover plate body 110 made of steel, avoiding potential difference corrosion between them. The explosion-proof valve 160 has high processing precision, a stable detonation value, and good safety performance of the battery cell.

[0052] Of course, in other embodiments, one sidewall of the housing 200 can also be connected to the explosion-proof valve 160 using the aforementioned explosion-proof valve mounting structure. That is, one sidewall of the housing 200 can also serve as a mounting plate for the explosion-proof valve 160.

[0053] The remaining structures in this embodiment are the same as those in Embodiment 1, and will not be described again here.

[0054] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. An explosion-proof valve installation structure, characterized in that, include: The mounting plate has a protrusion facing the electrode group, and the side of the protrusion away from the electrode group forms a receiving groove. The bottom of the receiving groove has a through first mounting hole. A fixing component is disposed at the receiving groove. The fixing component includes a connecting block and a plastic-coated component. The plastic-coated component wraps around the circumference of the connecting block, at least a portion of the end face of the connecting block near the electrode group, and a portion of the end face of the connecting block away from the electrode group. The plastic-coated component and the connecting block are integrally formed. A second mounting hole is provided at the center of the connecting block, and a first mounting groove is provided in the circumference of the second mounting hole near the electrode group. A first plastic component is disposed along a first direction on the side of the mounting plate near the electrode assembly; The second plastic part is disposed along the first direction on the side of the mounting plate opposite to the electrode group; A current-guiding terminal is disposed along a first direction through the first plastic part, the mounting plate and the second plastic part. The current-guiding terminal presses the first plastic part and the second plastic part against the mounting plate. The circumferential edge of the second plastic part abuts against the end face of the connecting block on the side away from the electrode group, which is wrapped by the plastic part, so as to press the fixing component against the mounting plate. An explosion-proof valve, wherein the circumferential edge of the explosion-proof valve is accommodated in the first mounting groove on the connecting block, the explosion-proof valve and the connecting block are made of the same material, and the first mounting hole and the second mounting hole can communicate after the explosion-proof valve is opened; A first sealing element is disposed along a first direction between the mounting plate and the explosion-proof valve, and between the mounting plate and the connecting block, wherein the connecting block presses the explosion-proof valve against the first sealing element.

2. The explosion-proof valve installation structure according to claim 1, characterized in that, Along the first direction, the distance between the bottom wall of the first mounting groove and the end face of the connecting block on the side opposite to the pole group is e; The value of e is in the range of 0.5mm≤e≤2mm.

3. The explosion-proof valve installation structure according to claim 1, characterized in that, Along the second direction, the width of the contact surface between the first seal and the connecting block is d2, and the width of the overlapping portion of the first seal, the explosion-proof valve, and the protrusion is d3. The range of values ​​for d2 is: 1mm ≤ d2 ≤ 2mm; The range of d3 is: 1mm≤d3≤2mm.

4. The explosion-proof valve installation structure according to claim 1, characterized in that, The connecting block has a second mounting groove on the end face away from the electrode group. The second mounting groove is located in the circumference of the connecting block. The plastic-coated part includes a first horizontal part, a vertical part, and a second horizontal part. The first horizontal part wraps around a portion of the end face of the connecting block near the electrode group. The vertical part wraps around the circumference of the connecting block and is spaced apart from the sidewall of the receiving groove. The second horizontal part wraps around a portion of the end face of the connecting block away from the electrode group and is located in the second mounting groove. The second plastic part abuts against the second horizontal part in a first direction.

5. The explosion-proof valve installation structure according to claim 4, characterized in that, Along the first direction, the distance between the bottom wall of the second mounting groove and the end face of the connecting block facing the pole group is c; The value of c is in the range of 0.5mm≤c≤2mm.

6. The explosion-proof valve installation structure according to claim 4, characterized in that, The current guiding terminal includes a first plate, a second plate, and a column. The second plate and the column are integrally formed. The first plate is located on the side of the first plastic part closer to the electrode group, and the second plate is located on the side of the second plastic part away from the electrode group. The column passes through the second plastic part, the mounting plate, and the first plastic part and is connected to the first plate.

7. The explosion-proof valve installation structure according to claim 6, characterized in that, Along the second direction, the peripheral sidewall of the second plate is located on the side of the vertical part closer to the center of the plastic-coated part, and the distance between the peripheral sidewall of the connecting block and the peripheral sidewall of the second plate is b; The value of b is in the range of 0.5mm ≤ b ≤ 5mm.

8. The explosion-proof valve installation structure according to claim 6, characterized in that, Along the first direction, the thickness of the second plate is a; The range of values ​​for a is: 2mm ≤ a ≤ 5mm.

9. The explosion-proof valve installation structure according to claim 6, characterized in that, The explosion-proof valve mounting structure also includes a second sealing element, which is sleeved on the outside of the column and sandwiched between the column and the mounting plate.

10. A battery cell, characterized in that, The explosion-proof valve mounting structure includes any one of claims 1-9.

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