Battery cover plate and battery

Abstract

The invention belongs to the technical field of batteries, and discloses a battery cover plate and a battery, the battery cover plate comprises a cover plate body and a pole module, the cover plate body comprises a mounting part and a capacity expansion part, the mounting part is of a solid flat plate structure and is bent towards a pole group, and an included angle between the mounting part and the capacity expansion part towards the pole group is an obtuse angle; the capacity expansion part is of a hollow convex structure, the pole module is in insulated connection with the mounting part, and the part, exceeding the outer side of the cover plate body, of the pole module is lower than the capacity expansion part. Therefore, on one hand, the space originally occupied by the pole module protruding out of the cover plate body is effectively utilized, the occupation of the outer side space is reduced, the assembling rate of the battery module is improved, the pole module is protected through the capacity expansion part, and damage caused by collision is avoided, and on the other hand, due to the fact that the capacity expansion part is of a hollow protruding structure, the capacity expansion part is not damaged. Therefore, the space utilization rate between the pole group and the cover plate body is improved by utilizing the space inside the capacity expansion part, the size of the pole group is increased, and the battery capacity is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a battery cover plate and a battery. BACKGROUND

[0002] As an important component of lithium battery, the structural design of battery cover plate not only affects the basic performance of battery (such as capacity, charge and discharge efficiency), but also directly relates to the safety and long-term reliability of battery. The main structure of battery cover plate includes conductive pole, light aluminum plate, riveting block, outer insulating part, inner insulating part, sealing part and explosion-proof valve, etc.

[0003] At present, the light aluminum plate of traditional battery cover plate is usually a flat plate structure. The conductive pole passes through one end of the light aluminum plate and is connected with the light aluminum plate through the riveting block, and the outer insulating part is arranged between the riveting block and the light aluminum plate for insulation protection; the other end is located on the other side of the light aluminum plate and is welded with the tab of the pole group, and the inner insulating part is used to realize the insulation protection of the conductive pole and the light aluminum plate.

[0004] This structure causes two problems after the assembly of the traditional battery cover plate is completed: on the one hand, the riveting block and the outer insulating part on the outside of the light aluminum plate protrude from the plate surface due to the superimposed installation, which occupies additional external space and affects the grouping rate of the battery module; on the other hand, the conductive pole and the inner insulating part on the other side of the light aluminum plate also protrude from the plate surface, which occupies the internal space, resulting in low space utilization rate between the pole group and the light aluminum plate, limiting the volume of the pole group, and thus reducing the battery capacity. SUMMARY

[0005] The purpose of the present application is to provide a battery cover plate and a battery, which not only saves the assembly space of the battery module and improves the grouping rate of the battery module, but also improves the utilization rate of the internal space, increases the volume of the pole group, and improves the battery capacity.

[0006] To achieve this purpose, the present application adopts the following technical solutions:

[0007] On the one hand, a battery cover plate is provided, which comprises:

[0008] A cover plate body, the cover plate body comprises a mounting part and an expansion part, the mounting part is a solid flat plate structure and is bent towards the direction of the pole group, the included angle between the mounting part and the expansion part towards the pole group is obtuse, and the expansion part is a hollow protruding structure formed by the cover plate body protruding from the inner side towards the outer side away from the pole group;

[0009] A pole group, the pole group is insulatedly connected with the mounting part, and the part of the pole group beyond the outer side of the cover plate body is lower than the height of the expansion part.

[0010] Optionally, the cover plate body further includes a connecting portion, which is parallel to the expansion portion and located on the side of the mounting portion opposite to the expansion portion;

[0011] The length of the cover plate body along the first direction is W1, and the distance between the side of the connecting part away from the mounting part and the junction of the expansion part and the mounting part along the first direction is W2, and satisfies 0.3≤W2 / W1≤0.5.

[0012] Optionally, the length of the mounting part in the direction parallel to the mounting part is L1, and the length of the pole module in the direction parallel to the mounting part is L2, and the length satisfies 11mm≤L1-L2≤18mm.

[0013] Optionally, the electrode module includes a conductive electrode post, a riveting block, an outer insulating component, and an inner insulating component. The conductive electrode post includes a column portion and a plate portion. The column portion passes through the mounting portion and is riveted to the riveting block. The column portion is perpendicular to the mounting portion. The outer insulating component is disposed between the riveting block and the mounting portion. The inner insulating component is disposed between the plate portion and the mounting portion. The plate portion is used to weld to the electrode tabs of the electrode assembly.

[0014] The cross-section of the column is elliptical, the minor axis of the column is A, the major axis of the column is B, and 1≤B / A≤3.5.

[0015] Optionally, the expansion section includes a top protective plate and side protective plates surrounding the top protective plate. The thickness of the top protective plate is T1, and the thickness of the side protective plates is T2, satisfying 0.5≤T2 / T1≤0.75.

[0016] Optionally, the thickness T2 of the side protective plate satisfies 1mm≤T2≤1.5mm.

[0017] Optionally, the angle between the mounting portion and the expansion portion toward the pole group is N, and satisfies 120°≤N≤145°.

[0018] Optionally, the height dimension of the expansion portion along the second direction is H, and satisfies 8mm≤H≤20mm.

[0019] Optionally, the cover plate body has an insertion protrusion with the same outline as the cover plate body on the inner side facing the pole group.

[0020] On the other hand, a battery is provided, the battery including an electrode assembly, a battery housing and a battery cover as described in any of the preceding claims, the battery housing being a hollow housing structure having at least one opening, and the battery cover being disposed at the opening of the battery housing to close the battery housing and form a receiving cavity for accommodating the electrode assembly.

[0021] The beneficial effects of this invention are:

[0022] This invention provides a battery cover plate. The cover plate body is designed with a mounting portion and an expansion portion at a specific angle. The expansion portion is a hollow, protruding structure, and the portion of the terminal module extending beyond the cover plate body is lower than the height of the expansion portion. This effectively utilizes the space previously occupied by the protruding terminal module, reducing the space occupied on the outside of the battery cover plate and increasing the battery module assembly rate. Furthermore, the protruding expansion portion provides protection for the terminal module, preventing damage from impacts. On the other hand, because the expansion portion is a hollow, protruding structure, the terminal assembly utilizes the space inside the expansion portion, improving the space utilization between the terminal assembly and the cover plate body, increasing the terminal assembly volume, and ultimately increasing battery capacity.

[0023] The present invention also provides a battery that, by applying the aforementioned battery cover, not only reduces the external space occupied but also expands the internal space, thereby increasing the volume of the electrode assembly and enhancing the power supply capacity. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the top structure of the battery cover provided by the present invention;

[0025] Figure 2 This is a schematic diagram of the bottom structure of the battery cover provided by the present invention;

[0026] Figure 3 This is a longitudinal cross-sectional view of the battery cover plate provided by the present invention;

[0027] Figure 4 This is a cross-sectional view of the area where the terminal module is located in the battery cover provided by the present invention;

[0028] Figure 5 This is a partial structural diagram of a battery using the aforementioned battery cover provided by the present invention;

[0029] Figure 6 This is a partial structural cross-sectional view of a battery using the aforementioned battery cover plate provided by the present invention.

[0030] In the picture:

[0031] 100. Electrode assembly; 101. Protrusion; 102. Angled portion; 200. Battery casing;

[0032] 1. Cover plate body; 11. Mounting part; 12. Expansion part; 121. Top protective plate; 122. Side protective plate; 13. Connecting part; 14. Insertion protrusion;

[0033] 2. Electrode post module; 21. Conductive electrode post; 211. Post body; 212. Plate body; 22. Riveting block; 23. Outer insulating component; 24. Inner insulating component. Detailed Implementation

[0034] 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.

[0035] 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.

[0036] 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.

[0037] In the description of this embodiment, the terms "upper," "lower," "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.

[0038] Because traditional battery covers have flat aluminum plates, the rivet blocks and outer insulation components on the outside of the aluminum plate protrude from the plate surface due to stacking, resulting in additional external space occupation and affecting the battery module assembly rate. On the other hand, the conductive electrode posts and inner insulation components on the other side of the aluminum plate also protrude from the plate surface, occupying internal space. This leads to low space utilization between the electrode assembly and the aluminum plate, limiting the electrode assembly volume and thus reducing battery capacity.

[0039] Therefore, in order to reduce the space occupied by the battery cover in the external and internal spaces, improve the battery module assembly rate, and increase battery capacity, this embodiment provides a battery cover. For ease of description, the length direction of the battery cover is defined as the first direction, and the thickness direction of the battery cover is defined as the second direction.

[0040] like Figures 1 to 6 As shown, the battery cover includes a cover body 1 and a terminal module 2. The cover body 1 includes a mounting part 11 and an expansion part 12. The mounting part 11 is a solid flat plate structure and is bent towards the terminal group 100. The angle between the mounting part 11 and the expansion part 12 towards the terminal group 100 is an obtuse angle. The expansion part 12 is a hollow protrusion structure formed by the cover body 1 protruding from the inner side towards the terminal group 100 to the outer side away from the terminal group 100. The terminal module 2 is insulated from the mounting part 11. The part of the terminal module 2 that extends beyond the outer side of the cover body 1 is lower than the height of the expansion part 12.

[0041] The battery cover is designed with a mounting portion 11 and an expansion portion 12 at a specific angle. The expansion portion 12 is a hollow protruding structure, and the portion of the terminal module 2 extending beyond the outer side of the cover body 1 is lower than the height of the expansion portion 12. This effectively utilizes the space originally occupied by the terminal module 2 protruding from the cover body 1, reducing the space occupied on the outer side of the battery cover and improving the battery module assembly rate. The protruding expansion portion 12 also provides protection for the terminal module 2, preventing damage from impacts. Furthermore, because the expansion portion 12 is a hollow protruding structure, the electrode assembly 100 can utilize the space inside the expansion portion 12, improving the space utilization between the electrode assembly 100 and the cover body 1, increasing the volume of the electrode assembly 100, and improving the battery capacity.

[0042] Optionally, such as Figure 3 As shown, the cover body 1 also includes a connecting part 13, which is parallel to the expansion part 12 and located on the side of the mounting part 11 away from the expansion part 12.

[0043] The length dimension of the cover plate body 1 along the first direction is W1, and the distance dimension along the first direction between the side of the connecting part 13 away from the mounting part 11 and the junction of the expansion part 12 and the mounting part 11 is W2, and satisfies 0.3≤W2 / W1≤0.5.

[0044] By limiting the ratio between the distance W2 along the first direction between the side of the connecting part 13 away from the mounting part 11 and the junction of the expansion part 12 and the mounting part 11, and the length W1 of the cover body 1 along the first direction, such that 0.3≤W2 / W1≤0.5, we can avoid the following: on the one hand, the total length of the mounting part 11 and the connecting part 13 along the first direction is too small relative to the length of the cover body 1, resulting in insufficient area of ​​the mounting part 11 for mounting the electrode module 2, leading to a reduction in the size of the electrode module 2 and thus reducing the current carrying capacity; on the other hand, we can avoid the following: the total length of the mounting part 11 and the connecting part 13 along the first direction is too large relative to the length of the cover body 1, resulting in a reduction in the size of the expansion part 12, which would compress the space for expanding the volume of the electrode assembly 100 and reduce the capacity expansion effect of the battery.

[0045] The ratio between the distance W2 between the side of the connecting part 13 away from the mounting part 11 and the junction of the expansion part 12 and the mounting part 11 along the first direction and the length W1 of the cover body 1 along the first direction can be any value between 0.3 and 0.5 or any range between two values, such as 0.3, 0.35, 0.4, 0.45, 0.5, etc.

[0046] Optionally, such as Figure 3 As shown, the length of the mounting portion 11 in the direction parallel to the mounting portion 11 is L1, and the length of the pole module 2 in the direction parallel to the mounting portion 11 is L2, satisfying 11mm≤L1-L2≤18mm. By limiting the difference between the length L1 of the mounting portion 11 in the direction parallel to the mounting portion 11 and the length L2 of the pole module 2 in the direction parallel to the mounting portion 11, ensuring that 11mm≤L1-L2≤18mm, sufficient clearance is maintained between the edge of the pole module 2 and the edge of the mounting portion 11. This avoids an excessively small clearance, which would increase the probability of damage to the pole module 2 due to impacts. On the other hand, it avoids an excessively large clearance between the edge of the pole module 2 and the edge of the mounting portion 11, which would reduce the size of the pole module 2 given a fixed size of the mounting portion 11, thereby reducing the area of ​​the pole module 2 used for current flow and decreasing its current flow capacity.

[0047] The difference between the length L1 of the mounting part 11 in the direction parallel to the mounting part 11 and the length L2 of the pole module 2 in the direction parallel to the mounting part 11 can be any value between 11mm and 18mm or any range between two values, such as 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, etc.

[0048] Optionally, such as Figure 3 , Figure 4As shown, the electrode module 2 includes a conductive electrode post 21, a riveting block 22, an outer insulating component 23, and an inner insulating component 24. The conductive electrode post 21 includes a post body 211 and a plate body 212. The post body 211 passes through the mounting part 11 and is riveted to the riveting block 22. The post body 211 is perpendicular to the mounting part 11. The outer insulating component 23 is disposed between the riveting block 22 and the mounting part 11. The inner insulating component 24 is disposed between the plate body 212 and the mounting part 11. The plate body 212 is used to weld to the electrode tabs of the electrode assembly 100.

[0049] The cross-section of the column part 211 is elliptical. The minor axis dimension of the column part 211 is A, and the major axis dimension of the column part 211 is B, and 1≤B / A≤3.5 is satisfied.

[0050] By setting the cross-section of the column portion 211 to an elliptical shape, the contact area between the column portion 211 and the riveting block 22 is increased. This improves the connection strength and the flow area of ​​the column portion 211, enhancing its flow capacity. Since the cover plate body 1 is usually a long and narrow structure, when designing the elliptical column portion 211, the minor axis dimension A of the column portion 211 needs to be determined first, and then the major axis dimension of the column portion 211 needs to be calculated using proportional relationships. By limiting the ratio of the major axis dimension B of the column portion 211 to the minor axis dimension A, it is ensured that 1≤B / A≤3.5. This avoids the major axis dimension B being too small relative to the minor axis dimension A, which would reduce the flow capacity of the column portion 211, and also avoids the major axis dimension B being too large relative to the minor axis dimension A, which would increase the difficulty of pressing the column portion 211 and reduce production efficiency.

[0051] The ratio of the major axis dimension B of the column portion 211 to the minor axis dimension A of the column portion 211 can be any value between 1 and 3.5 or a range between any two values, such as 1, 1.5, 2, 2.5, 3, 3.5, etc.

[0052] In this embodiment, the portion of the pole module 2 that extends beyond the outer side of the cover plate body 1 is the total height of the rivet block 22 and the outer insulating component 23. The projection of the rivet block 22 and the outer insulating component 23 on the mounting part 11 does not exceed the mounting part 11, thereby avoiding damage in the event of a collision. In addition, the mounting part 11 is provided with a pole through hole for the insertion of the pole body 211.

[0053] In this embodiment, to verify the impact of the above parameter limitations on the battery cover provided in this embodiment, as shown in Table 1, six sets of embodiments and six sets of comparative examples are provided for verification.

[0054] Table 1

[0055]

[0056] A comparison of Examples 1 to 6 with Comparative Examples 1 to 2 reveals that when the ratio of the distance W2 between the side of the connecting portion 13 away from the mounting portion 11 and the junction of the expansion portion 12 and the mounting portion 11 along the first direction to the length W1 of the cover plate body 1 along the first direction is less than the minimum value of 0.3 ≤ W2 / W1 ≤ 0.5, the total length of the mounting portion 11 and the connecting portion 13 along the first direction is too small relative to the length of the cover plate body 1. This results in insufficient area of ​​the mounting portion 11 for mounting the pole post module 2, thereby reducing the size of the pole post module. The size of 2 reduces the current carrying capacity; when the ratio of the distance W2 between the side of the connecting part 13 away from the mounting part 11 and the junction of the expansion part 12 and the mounting part 11 along the first direction is greater than the maximum value of 0.3≤W2 / W1≤0.5, the total length of the mounting part 11 and the connecting part 13 along the first direction is too large relative to the length of the cover body 1, which causes the expansion part 12 to shrink, and the space used to expand the volume of the electrode group 100 is compressed, thereby reducing the capacity expansion effect of the battery.

[0057] A comparison of Examples 1 to 6 with Comparative Examples 3 to 4 reveals that when the difference between the length L1 of the mounting portion 11 in the direction parallel to the mounting portion 11 and the length L2 of the pole module 2 in the direction parallel to the mounting portion 11 is less than the minimum value of 11mm ≤ L1 - L2 ≤ 18mm, the gap between the edge of the pole module 2 and the edge of the mounting portion 11 becomes too small, increasing the probability of damage to the pole module 2 due to impact. When the difference between the length L1 of the mounting portion 11 in the direction parallel to the mounting portion 11 and the length L2 of the pole module 2 in the direction parallel to the mounting portion 11 is greater than the maximum value of 11mm ≤ L1 - L2 ≤ 18mm, the gap between the edge of the pole module 2 and the edge of the mounting portion 11 becomes too large, causing the size of the pole module 2 to be reduced under the premise that the size of the mounting portion 11 is constant, thereby reducing the area of ​​the pole module 2 used for current flow and reducing its current flow capacity.

[0058] A comparison of Examples 1 to 6 with Comparative Examples 5 to 6 reveals that when the ratio of the major axis dimension B to the minor axis dimension A of the column portion 211 is less than the minimum value of 1≤B / A≤3.5, the major axis dimension B is too small relative to the minor axis dimension A, resulting in a reduction in the flow capacity of the column portion 211. When the ratio of the major axis dimension B to the minor axis dimension A of the column portion 211 is greater than the maximum value of 1≤B / A≤3.5, the major axis dimension B is too large relative to the minor axis dimension A, resulting in an increase in the difficulty of pressing and forming the column portion 211 and a reduction in production efficiency.

[0059] Optionally, such as Figure 3As shown, the expansion section 12 includes a top protective plate 121 and a side protective plate 122 surrounding the top protective plate 121. The thickness of the top protective plate 121 is T1, and the thickness of the side protective plate 122 is T2, and both satisfy 0.5≤T2 / T1≤0.75.

[0060] Since the expansion section 12 is formed by a stamping and stretching process, the side protective plate 122 surrounding the top protective plate 121 on the expansion section 12 will become thinner due to stretching during forming. The thickness of the top protective plate 121 is basically equal to the thickness of the plate before forming. Therefore, by limiting the ratio between the thickness T2 of the side protective plate 122 and the thickness T1 of the top protective plate 121 to satisfy 0.5≤T2 / T1≤0.75, the side protective plate 122 is prevented from being too thin relative to the top protective plate 121, which would result in poor structural strength of the side protective plate 122 and inability to provide effective protection for the pole assembly 100 inserted into the expansion section 12, thus increasing the probability of damage due to impact. On the other hand, the side protective plate 122 is also prevented from being too thick relative to the top protective plate 121, which would increase the difficulty of forming.

[0061] The ratio between thickness dimension T2 and thickness dimension T1 can be any value between 0.5 and 0.75 or any range between any two values, such as 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, etc.

[0062] Optionally, such as Figure 3 As shown, the thickness T2 of the side protective plate 122 satisfies 1mm ≤ T2 ≤ 1.5mm. By further individually limiting the thickness T2 of the side protective plate 122, it is possible to avoid the side protective plate 122 being too thin, resulting in insufficient structural strength and protection, and to avoid the side protective plate 122 being too thick, which would lead to an excessively thick top protective plate 121 when calculating its thickness, thus increasing the processing difficulty.

[0063] The thickness T2 of the side protection plate 122 can be any value between 1mm and 1.5mm or any range between two values, such as 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, etc.

[0064] Optionally, such as Figure 3As shown, the angle N between the mounting portion 11 and the expansion portion 12 toward the electrode assembly 100 satisfies 120°≤N≤145°. By limiting the angle N between the mounting portion 11 and the expansion portion 12 toward the electrode assembly 100 to satisfy 120°≤N≤145°, it avoids two problems: firstly, an angle N that is too small, causing the mounting portion 11 to bend excessively toward the electrode assembly 100, thereby reducing the external dimensions of the electrode assembly 100 and decreasing the battery capacity; secondly, it avoids an angle N that is too large, causing the mounting portion 11 to bend excessively away from the electrode assembly 100, thereby causing the electrode module 2 to be too close to the top of the expansion portion 12, increasing the probability of the electrode module 2 being damaged by impact.

[0065] The included angle N between the mounting part 11 and the expansion part 12 toward the pole group 100 can be any value between 120° and 145° or any range between two values, such as 120°, 125°, 130°, 140°, 145°, etc.

[0066] Optionally, such as Figure 3 As shown, the height dimension of the expansion section 12 along the second direction is H, and it satisfies 8mm≤H≤20mm. By limiting the height dimension H of the expansion section 12 along the second direction to satisfy 8mm≤H≤20mm, on the one hand, it avoids the expansion section 12 being too small, which would not only result in a small height difference between the expansion section 12 and the part of the electrode module 2 protruding from the cover plate body 1, leading to insufficient protection for the part of the electrode module 2 protruding from the cover plate body 1, but also result in limited space for the expansion section 12 to accommodate the electrode group 100, limiting the increase in battery capacity. On the other hand, it avoids the expansion section 12 being too large along the second direction, which would increase the molding difficulty and cause excessive stretching, making the side protective plate 122 of the expansion section 12 too thin and with poor protection capabilities, making the electrode group 100 easily damaged by impacts.

[0067] The height dimension H of the expansion section 12 along the second direction can be any value between 8mm and 20mm or any range between two values, such as 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, etc.

[0068] In this embodiment, to verify the impact of the above parameter limitations on the battery cover provided in this embodiment, as shown in Table 2, six sets of embodiments and six sets of comparative examples are provided for verification.

[0069] Table 2

[0070]

[0071] A comparison of Examples 7 to 12 with Comparative Examples 7 to 8 reveals that when the ratio between the thickness T2 of the side protective plate 122 and the thickness T1 of the top protective plate 121 is less than the minimum value of 0.5 ≤ T2 / T1 ≤ 0.75, the side protective plate 122 is too thin relative to the top protective plate 121, resulting in poor structural strength of the side protective plate 122, which cannot provide effective protection for the pole assembly 100 inserted into the expansion section 12, thus increasing the probability of damage due to impact. When the ratio between the thickness T2 of the side protective plate 122 and the thickness T1 of the top protective plate 121 is greater than the maximum value of 0.5 ≤ T2 / T1 ≤ 0.75, the side protective plate 122 is too thick relative to the top protective plate 121, thereby increasing the difficulty of molding.

[0072] A comparison of Examples 7 to 12 with Comparative Examples 9 to 10 shows that when the angle N between the mounting portion 11 and the expansion portion 12 toward the electrode group 100 is less than the minimum value of 120°≤N≤145°, the angle N is too small, causing the mounting portion 11 to bend excessively toward the electrode group 100, thereby reducing the external dimensions of the electrode group 100 and lowering the battery capacity. When the angle N between the mounting portion 11 and the expansion portion 12 toward the electrode group 100 is greater than the maximum value of 120°≤N≤145°, the angle N is too large, causing the mounting portion 11 to bend excessively toward the direction away from the electrode group 100, thereby causing the electrode module 2 to be too close to the top of the expansion portion 12, increasing the probability of the electrode module 2 being damaged by impact.

[0073] A comparison of Examples 7 to 12 with Comparative Examples 11 to 12 reveals that when the height dimension H of the expansion section 12 along the second direction is less than the minimum value of 8mm ≤ H ≤ 20mm, the height of the expansion section 12 is too small. This not only results in a small height difference between the expansion section 12 and the portion of the electrode module 2 protruding from the cover plate body 1, leading to insufficient protection for the portion of the electrode module 2 protruding from the cover plate body 1, but also limits the space available for the expansion section 12 to accommodate the electrode assembly 100, thus restricting the increase in battery capacity. When the height dimension H of the expansion section 12 along the second direction is greater than the maximum value of 8mm ≤ H ≤ 20mm, the height dimension of the expansion section 12 along the second direction is too large, increasing the molding difficulty and causing excessive stretching. This results in the side protective plate 122 of the expansion section 12 being too thin, with poor protective capability, making the electrode assembly 100 easily damaged by impacts.

[0074] Optionally, such as Figure 1As shown, the inner side of the cover plate body 1 facing the electrode assembly 100 is provided with an insertion protrusion 14 that has the same outline as the cover plate body 1. By providing an insertion protrusion 14 that has the same outline as the cover plate body 1 on the inner side of the cover plate body 1 facing the electrode assembly 100, the cover plate body 1 can be assembled by inserting it into the battery housing 200, thereby facilitating subsequent welding operations.

[0075] In this embodiment, the outline of the cover plate body 1 is the shape of the cover plate body 1 after it has been formed by stamping and stretching to form the mounting part 11, the expansion part 12 and the connecting part 13.

[0076] In this embodiment, as Figure 5 , Figure 6 As shown, a battery is also provided, comprising an electrode assembly 100, a battery casing 200, and a battery cover plate according to this embodiment. The battery casing 200 is a hollow casing structure with at least one opening. The battery cover plate is disposed at the opening of the battery casing 200, closing the battery casing 200 to form a receiving cavity for accommodating the electrode assembly 100. By using the aforementioned battery cover plate, this battery not only reduces the external space occupied but also expands the internal space, increasing the volume of the electrode assembly 100 and thereby enhancing the power supply capacity.

[0077] In order to adapt to the battery cover provided in this embodiment, the shape of the battery housing 200 is adapted to the shape of the battery cover. The electrode assembly 100 is provided with a protrusion 101 that is inserted into the expansion part 12, and an angled part 102 corresponding to the mounting part 11.

[0078] In this embodiment, in order to ensure the safety of the battery, an explosion-proof valve is also provided on the battery. The explosion-proof valve can be provided on the battery housing 200 or on the expansion portion 12 of the battery cover provided in this embodiment.

[0079] In this embodiment, the battery is a blade battery. Since the blade battery has a structure with tabs on both sides of the electrode group 100, it is provided with two battery covers. Therefore, based on the battery covers provided in this embodiment, two types of blade batteries can be derived. One type has two battery covers of the same type as the battery cover provided in this embodiment, and the other type has one battery cover of the same type as the battery cover provided in this embodiment, while the other retains the traditional battery cover type.

[0080] 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. A battery cover, characterized in that, The battery cover includes: The cover plate body includes a mounting part and an expansion part. The mounting part is a solid flat plate structure and is bent towards the electrode group. The angle between the mounting part and the expansion part towards the electrode group is an obtuse angle. The expansion part is a hollow protrusion structure formed by the cover plate body protruding from the inside towards the electrode group to the outside away from the electrode group. The pole module is insulated from the mounting part, and the portion of the pole module extending beyond the outer side of the cover plate body is lower than the height of the expansion part.

2. The battery cover according to claim 1, characterized in that, The cover plate body also includes a connecting part, which is parallel to the expansion part and located on the side of the mounting part away from the expansion part; The length of the cover plate body along the first direction is W1, and the distance between the side of the connecting part away from the mounting part and the junction of the expansion part and the mounting part along the first direction is W2, and satisfies 0.3≤W2 / W1≤0.

5.

3. The battery cover according to claim 1, characterized in that, The length of the mounting part along the direction parallel to the mounting part is L1, and the length of the pole module along the direction parallel to the mounting part is L2, and both satisfy 11mm≤L1-L2≤18mm.

4. The battery cover according to claim 1, characterized in that, The electrode module includes a conductive electrode post, a riveting block, an outer insulating component, and an inner insulating component. The conductive electrode post includes a column portion and a plate portion. The column portion passes through the mounting portion and is riveted to the riveting block. The column portion is perpendicular to the mounting portion. The outer insulating component is disposed between the riveting block and the mounting portion. The inner insulating component is disposed between the plate portion and the mounting portion. The plate portion is used to weld to the electrode tabs of the electrode assembly. The cross-section of the column is elliptical, the minor axis of the column is A, the major axis of the column is B, and 1≤B / A≤3.

5.

5. The battery cover according to claim 1, characterized in that, The expansion section includes a top protective plate and side protective plates surrounding the top protective plate. The thickness of the top protective plate is T1, and the thickness of the side protective plates is T2, satisfying 0.5≤T2 / T1≤0.

75.

6. The battery cover according to claim 5, characterized in that, The thickness T2 of the side protective plate satisfies 1mm≤T2≤1.5mm.

7. The battery cover according to claim 1, characterized in that, The angle between the mounting part and the expansion part toward the pole group is N, and satisfies 120°≤N≤145°.

8. The battery cover according to claim 1, characterized in that, The height dimension of the expansion section along the second direction is H, and it satisfies 8mm≤H≤20mm.

9. The battery cover according to claim 1, characterized in that, The cover plate body has an insertion protrusion with the same outline as the cover plate body on the inner side facing the pole group.

10. A battery, characterized in that, The battery includes an electrode assembly, a battery casing, and a battery cover as described in any one of claims 1-9. The battery casing is a hollow casing structure with at least one opening, and the battery cover is disposed at the opening of the battery casing to close the battery casing and form a receiving cavity for accommodating the electrode assembly.

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