Cover plate assembly, battery cell and electric device

Abstract

This application relates to a cover plate assembly, a battery cell, and an electrical device, belonging to the field of battery technology. The cover plate assembly includes a cover plate and a terminal post assembly. The terminal post assembly includes terminal posts disposed on the cover plate. Each terminal post includes a base and a column body, with one end of the column body connected to the base. The diameter of the connection between the column body and the base is b. The length of the terminal post assembly along a first direction is L. The width of the terminal post assembly along a second direction is W. Wherein, the first direction represents the length direction of the cover plate, and the second direction represents the width direction of the cover plate. Wherein, b, L, and W satisfy: W≥b+4; b≥; L<60mm; U represents the cell capacity; C represents the charge / discharge rate of the cell; n represents the number of terminal posts; σ1 represents the overcurrent coefficient of the terminal posts. This cover plate assembly, battery cell, and electrical device can simultaneously meet the width requirements of the cover plate, the overcurrent requirements of the terminal posts, the overcurrent requirements of the rivet blocks, and the welding effect between the terminal post assembly and the busbar.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a cover plate assembly, a battery cell, and an electrical device. Background Technology

[0002] Currently, the battery cell includes a cover plate, a terminal assembly, and a terminal group. The terminal assembly includes a terminal and a rivet block. The terminal is set on the cover plate and connected to the terminal group. The rivet block is sleeved on the terminal and welded to the busbar. The rivet block has a solder mark. Current is transmitted from the terminal group to the rivet block through the terminal and then to the busbar through the rivet block. In related technologies, firstly, to ensure the terminal block meets current requirements, its diameter needs to be increased, leading to an increase in the overall width of the terminal block assembly. This, in turn, increases the width of the cover plate, occupying more space. Secondly, to ensure the rivet block meets current requirements, the area of ​​the solder marks on the rivet block needs to be increased, necessitating a longer solder mark length (since the solder mark width is limited by the width of the terminal block assembly, the range for increase is small). Increasing the solder mark length leads to an increase in the overall length of the terminal block assembly, resulting in a larger length-to-width ratio. During assembly (e.g., assembling the terminal block), the surface of the terminal block assembly is prone to deformation, causing the surface flatness to fail to meet requirements. Ultimately, this leads to poor soldering between the terminal block assembly and the busbar, resulting in unsatisfactory welding performance. In summary, related technologies cannot simultaneously address the width requirements of the cover plate, the current requirements of the terminal block, the current requirements of the rivet block, and the welding performance between the terminal block assembly and the busbar. Summary of the Invention

[0003] To address the aforementioned technical problems, embodiments of this application provide a cover plate assembly, a battery cell, and an electrical device that can simultaneously meet the width requirements of the cover plate, the current-carrying requirements of the terminal post, the current-carrying requirements of the rivet block, and the welding effect between the terminal post assembly and the busbar.

[0004] In a first aspect, a cover plate assembly is provided, comprising:

[0005] Cover plate;

[0006] An electrode assembly includes an electrode post disposed on a cover plate; the electrode post includes a base and a column body, one end of the column body is connected to the base, the diameter of the connection between the column body and the base is b (in mm), the length of the electrode assembly along a first direction is L (in mm), and the width of the electrode assembly along a second direction is W (in mm); wherein, the first direction represents the length direction of the cover plate, and the second direction represents the width direction of the cover plate;

[0007] Wherein, b, L, and W satisfy: W ≥ b + 4; b ≥ L < 60 mm;

[0008] Wherein, U represents the capacity of the battery cell, in Ah; C represents the charge / discharge rate of the battery cell, in A / Ah; n represents the number of terminals; and σ1 represents the overcurrent coefficient of the terminal, in A / mm. 2 .

[0009] According to a first aspect of this application, the number of poles is two, and the two poles are distributed along the first direction;

[0010] The pole assembly also includes:

[0011] A rivet block is fitted onto the two columns, and the surface of the rivet block is provided with a solder mark for connecting the busbar, the solder mark being located between the two columns.

[0012] According to a first aspect of this application, the pole assembly is symmetrically arranged about a preset axis, the solder mark is symmetrically arranged about the preset axis, and the two poles are symmetrically arranged about the preset axis;

[0013] The length of the weld mark along the first direction is A, in mm; the width of the weld mark along the second direction is B, in mm; the distance between the edge of the connection between the column and the base and the edge of the weld mark along the first direction is a; and the distance between the edge of the column and the edge of the rivet block along the first direction is d, in mm.

[0014] The following conditions are met: A, B, a, and d.

[0015] A≥UC / (Bσ2β); L=A+2(a+b+d);

[0016] Wherein, σ2 represents the flow coefficient of the riveting block, with units of A / mm. 2 β represents the effective coefficient of the solder mark.

[0017] According to the first aspect of this application, B satisfies:

[0018] 2mm≤B≤4mm.

[0019] According to the first aspect of this application, a satisfies:

[0020] 1mm≤a≤2mm.

[0021] According to the first aspect of this application, d satisfies:

[0022] 2mm≤d≤3mm.

[0023] According to a first aspect of this application, the flatness of the surface of the rivet block is P, in mm, and P satisfies: P < 0.4 mm.

[0024] According to a first aspect of this application, the cover plate assembly further includes:

[0025] The first plastic part is sleeved on the two pillars. The first plastic part has a receiving groove, and the riveting block is disposed in the receiving groove.

[0026] Secondly, a battery cell is also provided, including:

[0027] The casing has an opening;

[0028] An electrode assembly is disposed within the housing, and the electrode assembly is provided with electrode tabs;

[0029] As described in the previous embodiment, the cover plate assembly is connected to the housing to close the opening; the base is electrically connected to the tab.

[0030] Thirdly, an electrical appliance is also provided, including:

[0031] The battery cell as described in the previous embodiment.

[0032] The cover plate assembly, battery cell, and electrical device provided in this application embodiment, in a first aspect, satisfy the following conditions by limiting the diameter b at the connection between the column and the base and the width W of the pole assembly along the second direction: W ≥ b + 4, b ≥ Firstly, by limiting the width of the pole assembly to a smaller value while ensuring that the current carrying capacity of the pole is met, the width of the cover plate can also be limited to a smaller value, reducing the space occupied by the cover plate. This balances the width requirements of the cover plate and the current carrying capacity of the pole. Secondly, by limiting the length L of the pole assembly along the first direction to satisfy: L < 60mm, the maximum length of the pole assembly along the first direction can be limited to a reasonable range while ensuring that the current carrying capacity of the rivet block is met. This avoids the problem of the surface flatness of the pole assembly not meeting the requirements due to the excessive length of the pole assembly, effectively improving the problem of easy cold solder joints between the pole assembly and the busbar, and improving the welding effect. In other words, it can balance the current carrying capacity of the pole assembly (rivet block) and the welding effect between the pole assembly (rivet block) and the busbar. Attached Figure Description

[0033] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0034] Figure 1 This is a schematic diagram of the structure of a battery cell provided for an exemplary embodiment of this application.

[0035] Figure 2 An exploded view of a cover plate assembly provided for an exemplary embodiment of this application.

[0036] Figure 3 This is a schematic diagram of the structure of a pole provided for an exemplary embodiment of this application.

[0037] Figure 4 This is a schematic diagram of the structure of a cover plate assembly provided for an exemplary embodiment of this application.

[0038] Reference numerals: 100-Cover assembly; 110-Cover; 111-Explosion-proof hole; 112-Mounting hole; 120-Pole post assembly; 121-Pole post; 1211-Base; 1212-Post; 122-Rivet block; 1221-Weld mark; 124-Sealing ring; 125-Explosion-proof valve; 126-Protective patch; 130-Second plastic part; 140-First plastic part; 141-Receiving groove; 200-Cell; 210-Housing; 220-Pole group; 221-Pole tab. Detailed Implementation

[0039] Hereinafter, exemplary embodiments according to this application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments of this application. It should be understood that this application is not limited to the exemplary embodiments described herein.

[0040] Figure 1 This is a schematic diagram of the structure of a battery cell provided for an exemplary embodiment of this application. Figure 1 As shown, the battery cell 200 provided in this application embodiment may include a housing 210 and an electrode group 220. The housing 210 has an opening, and the electrode group 220 can extend into the housing 210 through the opening. The housing 210 can protect the electrode group 220.

[0041] like Figure 1 As shown, the battery cell 200 may also include a cover assembly 100, which is connected to the housing 210. The cover assembly 100 can close the opening of the housing 210. Therefore, the cover assembly 100 can prevent foreign objects from entering the housing 210 and avoid the influence and damage of foreign objects on the electrode assembly 220.

[0042] Figure 2 An exploded view of a cover plate assembly provided for an exemplary embodiment of this application. Figure 1 and Figure 2As shown, the electrode assembly 220 is provided with electrode tabs 221, and the cover plate assembly 100 may include a cover plate 110 and an electrode post assembly 120. The cover plate 110 is connected to the aforementioned housing 210 and is used to close the opening of the housing 210.

[0043] Figure 3 This is a schematic diagram of the pole structure provided for an exemplary embodiment of this application. Figures 1 to 3 As shown, the pole assembly 120 may include a pole 121, which is disposed on the cover plate 110. The pole 121 includes a base 1211 and a column 1212. The base 1211 is electrically connected to the tab 221, and one end of the column 1212 is connected to the base 1211. Current can be input to or output to the pole assembly 220 through the base 1211 and the column 1212.

[0044] In one embodiment, the base 1211 and the tab 221 can be directly connected or indirectly connected through an adapter.

[0045] like Figure 2 As shown, the terminal assembly 120 may further include a sealing ring 124. The cover plate 110 has a mounting hole 112, and the sealing ring 124 is sleeved on the post 1212. The sealing ring 124 and the post 1212 are located within the mounting hole 112. The sealing ring 124 can isolate and insulate the outer wall of the post 1212 from the inner wall of the mounting hole 112, preventing the terminal 121 from directly contacting the cover plate 110 and preventing short circuit accidents in the cell 200.

[0046] like Figure 2 As shown, an explosion-proof hole 111 can be provided on the cover plate 110. Correspondingly, the cover plate assembly 100 can include an explosion-proof valve 125, which is disposed within the explosion-proof hole 111. In the event of an abnormality in the battery cell 200 (such as overcharging, over-discharging, or short circuit), a large amount of gas will be generated inside the electrode group 220. When the gas pressure inside the electrode group 220 exceeds the pressure threshold, the explosion-proof valve 125 can open to promptly release the gas inside the electrode group 220. This can prevent problems such as the battery cell 200 exploding or burning due to excessive gas pressure inside the electrode group 220.

[0047] like Figure 2 As shown, the cover assembly 100 may further include a protective patch 126, which covers the explosion-proof valve 125. In practical applications, the protective patch 126 can prevent residual electrolyte on the cover 110 from entering the explosion-proof valve 125 and avoid electrolyte corrosion of the explosion-proof valve 125.

[0048] like Figure 2As shown, the terminal assembly 120 may further include a first plastic part 140 and a riveting block 122. The first plastic part 140 is sleeved on the post body 1212 and has a receiving groove 141. The riveting block 122 is disposed in the receiving groove 141 and sleeved on the post body 1212. The first plastic part 140 can isolate and insulate the riveting block 122 from the cover plate 110, preventing the riveting block 122 from directly contacting the cover plate 110 and preventing short circuit accidents in the battery cell 200.

[0049] like Figure 2 As shown, the cover plate assembly 100 may include a second plastic part 130. The second plastic part 130 is disposed on the side of the cover plate 110 near the electrode group 220. The second plastic part 130 can be placed between the base 1211 and the cover plate 110 to avoid direct contact between the base 1211 and the cover plate 110 and prevent short circuit accidents in the battery cell 200.

[0050] Figure 4 This is a schematic diagram of the structure of a cover plate assembly provided for an exemplary embodiment of this application. Figures 2 to 4 As shown, the connection between the column 1212 and the base 1211 (see reference for details) Figure 2 and Figure 3 The diameter of the part indicated by the middle arrow K is b. In order to ensure that the pole post 121 can meet the overcurrent requirements (the overcurrent requirements of the pole post 121 in this embodiment can be understood as the overcurrent requirements at the connection between the pole post 1212 and the base 1211), it is necessary to ensure that the cross-sectional area at the connection between the pole post 1212 and the base 1211 is greater than the required overcurrent area, that is, it is necessary to satisfy:

[0051] Relation 1: In this context, n can be interpreted as the number of terminals 121; U can be interpreted as the capacity of cell 200, in Ah; C can be interpreted as the charge / discharge rate of cell 200, in A / Ah; and σ1 characterizes the overcurrent coefficient of terminal 121, in A / mm². 2 .

[0052] In one embodiment, the number n of poles 121 can be one, two, three, etc.

[0053] In one embodiment, the electrode post 121 is made of aluminum, and the current coefficient σ1 of the electrode post 121 can be 5-8 A / mm. 2 Values ​​can be taken within a range.

[0054] It should be noted that by transforming the aforementioned relation one, we can obtain:

[0055] Relation 2: b≥ .

[0056] It should be understood that, assuming the pole post 121 meets the overcurrent requirements, if b increases, the area occupied by the pole post 1212 in the pole post assembly 120 (specifically, the riveting block 122) will correspondingly increase, and the width of the pole post assembly 120 (refer to the pole post assembly 120 in...) will also increase. Figure 4 The width in the direction indicated by the Y-axis will increase accordingly. Therefore, after determining the number n of terminals 121, the capacity U of cell 200, the charge / discharge rate C of cell 200, and the overcurrent coefficient σ1 of terminals 121, the minimum value of b can be calculated according to equation two, i.e. .

[0057] like Figure 4 As shown, the pole assembly 120 is along the second direction (reference). Figure 4 The width of the rivet block 122 in the direction indicated by the Y-axis is W (that is, the width of the aforementioned rivet block 122 along the second direction is W). Once the diameter b is determined, the dimensions of the column 1212 are also determined accordingly. It is necessary to ensure that the rivet block 122 has sufficient margin in the second direction to guarantee the overall structural strength of the rivet block 122. Therefore, in this embodiment, the width W and diameter b satisfy:

[0058] Relationship 3: W≥b+4. In this way, while ensuring the overall structural strength of the riveting block 122, it is also possible to ensure that the riveting block 122 has enough space to manufacture the pole post 121.

[0059] It should be understood that the width W of the pole post assembly 120 directly determines the width of the cover plate 110. In order to reduce the space occupied by the cover plate 110, the minimum width of the pole post assembly 120 should be taken, that is, W=b+4.

[0060] It should be understood that Equations 2 and 3 can limit the width of the pole assembly 120 to a smaller value while ensuring that the current requirements of the pole 121 are met, thereby limiting the width of the cover plate 110 to a smaller value and reducing the space occupied by the cover plate 110. In other words, Equations 2 and 3 can balance the width requirement of the cover plate 110 (small space occupation) and the current requirements of the pole 121.

[0061] It should be noted that the rivet block 122 mentioned above can be used to weld to a busbar (not shown in the figure), and the rivet block 122 can transmit current between the pole 121 and the busbar. During the welding process between the rivet block 122 and the busbar, a solder mark 1221 will be formed on the surface of the rivet block 122.

[0062] It should be noted that after the width W of the pole assembly 120 is determined, the adjustable range of the width B of the solder mark 1221 on the rivet block 122 is also determined accordingly (the adjustable range of the width B of the solder mark 1221 will be described in detail later).

[0063] In related technologies, in order to ensure that the riveting block 122 can meet the overcurrent requirements, it is necessary to increase the area of ​​the solder mark 1221 on the riveting block 122, which requires extending the length of the solder mark 1221 (because the width of the solder mark 1221 is limited by the width of the pole assembly 120, the range that can be increased is small). The increase in the length of the solder mark 1221 will lead to an increase in the overall length of the pole assembly 120, which in turn leads to an increase in the length-to-width ratio of the pole assembly 120. During the assembly process (e.g., the assembly of the pole 121), the surface of the pole assembly 120 is prone to deformation, which makes the flatness of the surface of the pole assembly 120 unable to meet the requirements. Ultimately, this leads to a tendency for the pole assembly 120 (specifically the riveting block 122) to have a poor weld with the busbar, resulting in an unsatisfactory welding effect.

[0064] Therefore, in this embodiment of the application, the length L of the pole post assembly 120 along the first direction (that is, the overall length L of the riveting block 122 along the first direction) is limited, that is, the length L (in mm) of the pole post assembly 120 satisfies:

[0065] Equation 4: L < 60mm. This limits the length of the terminal assembly 120 along the first direction to a reasonable range, preventing the surface flatness of the terminal assembly 120 from failing to meet requirements due to excessive length. This effectively improves the problem of weak soldering between the terminal assembly 120 and the busbar, enhancing the welding effect. In other words, Equation 4 can balance the current requirements of the riveting block 122 with the welding effect between the terminal assembly 120 (specifically, the riveting block 122) and the busbar.

[0066] The following is a detailed description of the process of using Relationship 2, Relationship 3, and Relationship 4 to take into account the width requirement of cover plate 110 (small space occupation), the current flow requirement of pole post 121, the current flow requirement of riveting block 122, and the welding effect between pole post assembly 120 (specifically riveting block 122) and busbar.

[0067] During the manufacturing process, the diameter b required to meet the current requirements at the connection between the cell 200 and the base 121 can be determined first based on the cell's capacity U, charge / discharge rate C, number of terminals 121 n, current coefficient σ1 of terminals 121, and Equation 2. Then, the width W of the terminal assembly 120 can be determined according to Equation 3. After the width W of the terminal assembly 120 is determined, the width B of the solder mark 1221 is correspondingly determined. To meet the current requirements of the rivet block 122, the length of the solder mark 1221 is gradually increased, correspondingly increasing the length L of the terminal assembly 120. If the length L of the terminal assembly 120 is ≥ 60mm while meeting the current requirements of the rivet block 122, the flatness of the terminal assembly 120 surface will not meet the requirements (for reasons explained above), resulting in an unsatisfactory welding effect between the terminal assembly 120 and the busbar (specifically, between the rivet block 122 and the busbar). Based on this, the width W of the pole post assembly 120 needs to be readjusted according to Equation 3, appropriately increasing the width W of the pole post assembly 120. Then, according to the aforementioned process, it is determined whether the length L of the pole post assembly 120 satisfies Equation 4. If it does, the current width W of the pole post assembly 120 can be used as the actual design width, and the overall width of the cover plate 110 can be obtained accordingly. If it does not satisfy, the width W of the pole post assembly 120 will be adjusted again until the length L of the pole post assembly 120 satisfies Equation 4. In this way, under the combined constraints of Equations 2, 3, and 4, the embodiments of this application can take into account the width requirements of the cover plate 110 (small space occupation), the flow requirements of the pole post 121, the flow requirements of the riveting block 122, and the welding effect between the pole post assembly 120 and the busbar (the flatness of the surface of the pole post assembly 120 meets the requirements).

[0068] It should be noted that in practical applications, the rivet block 122 is directly welded to the busbar, and the solder mark 1221 is formed on the surface of the rivet block 122. The flatness of the aforementioned pole assembly 120 surface can also be understood as the flatness of the rivet block 122 surface.

[0069] Specifically, the flatness of the surface of the rivet block 122 is P, in mm. If the flatness P of the rivet block 122 is large, it will cause the rivet block 122 to be prone to poor welding when welding with the busbar, which will affect the welding effect between the rivet block 122 and the busbar.

[0070] Therefore, in this embodiment, the flatness P of the surface of the rivet block 122 is limited to the following range: P < 0.4 mm. This improves the aforementioned problem caused by excessive flatness of the surface of the rivet block 122.

[0071] It should be noted that, in this embodiment, the length of the pole post assembly 120 along the first direction can be understood as the length of the portion of the pole post assembly 120 protruding from the side of the cover plate 110 away from the pole group 220 along the first direction. Similarly, the width of the pole post assembly 120 along the second direction can be understood as the width of the portion of the pole post assembly 120 protruding from the side of the cover plate 110 away from the pole group 220 along the second direction.

[0072] That is, in this embodiment, the outer edge of the riveting block 122 can be considered as the outer edge of the pole assembly 120. The length of the riveting block 122 along the first direction can be considered as the length L of the pole assembly 120 along the first direction. The width of the riveting block 122 along the second direction can be considered as the width W of the pole assembly 120 along the second direction.

[0073] like Figure 2 and Figure 4 As shown, there are two pole posts 121, and the two pole posts 121 are along the first direction (reference). Figure 4 The rivet block 122 is distributed along the X-axis direction and can be fitted onto the pillars 1212 of the two pole posts 121, with the solder mark 1221 located between the two pillars 1212. This design shortens the path of current transfer from the two pillars 1212 to the solder mark 1221, effectively reducing conduction resistance and heat generation. Furthermore, it fully utilizes the portion of the rivet block 122 located between the two pillars 1212, providing a larger area for the solder mark 1221. The larger area of ​​the solder mark 1221 allows it to better meet greater overcurrent requirements.

[0074] It should be noted that, as mentioned earlier, during the process of increasing the length of the solder mark 1221, the columns 1212 at both ends of the solder mark 1221 will be far apart. After the columns 1212 at both ends are riveted to the riveting block 122, the portion of the riveting block 122 located between the columns 1212 at both ends is prone to protrusion. That is, the flatness of the area where the solder mark 1221 is located cannot meet the requirements, which leads to a tendency for the riveting block 122 to have a weak weld with the busbar, resulting in an unsatisfactory welding effect. Therefore, by using the aforementioned Equation 4, the length of the solder mark 1221 along the first direction can be limited, thereby avoiding the columns 1212 at both ends of the solder mark 1221 being far apart and ensuring that the flatness of the surface of the riveting block 122 can meet the welding requirements.

[0075] like Figure 4 As shown, the length of the solder mark 1221 along the first direction is A, in mm; the width of the solder mark 1221 along the second direction is B, in mm; to ensure that the riveting block 122 meets the overcurrent requirements, A and B can satisfy:

[0076] Relationship 5: ABβ≥UC / σ2.

[0077] It should be noted that σ2 can be understood as the flow coefficient of the riveting block 122, with units of A / mm. 2 .

[0078] In one embodiment, the riveting block 122 can be made of aluminum, and the flow coefficient σ2 of the riveting block 122 can be 5-8 A / mm. 2 Values ​​can be taken within a range.

[0079] It should be noted that β can be understood as the effective coefficient of solder mark 1221. That is, after the riveting block 122 is welded to the busbar, the effective current-carrying area of ​​solder mark 1221 that can carry current is the proportion of the total area of ​​solder mark 1221. The product of A, B, and β can be understood as the effective current-carrying area of ​​solder mark 1221 after welding.

[0080] In one embodiment, β can be selected as 0.8, 0.7, etc.

[0081] Transforming relation five yields:

[0082] Relationship 6: A≥UC / (Bσ2β).

[0083] like Figure 4 As shown, the entire pole assembly 120 is positioned about a preset axis (reference). Figure 4 The axes (indicated by the middle arrow E) are symmetrically arranged, the solder stamps 1221 are symmetrically arranged about the preset axis, and the two pole posts 121 are symmetrically arranged about the preset axis. The distance between the edge of the connection between the pole 1212 and the base 1211 and the edge of the solder stamp 1221 along the first direction is a, and the distance between the edge of the pole 1212 and the edge of the riveting block 122 along the first direction is d. a and d can satisfy:

[0084] Relationship 7: L = A + 2(a + b + d).

[0085] It should be noted that, in combination Figure 4 Since the width W of the pole post assembly 120 is determined, the range of values ​​for the width B of the solder mark 1221 is also determined accordingly. Therefore, according to Equation 6, the length A of the solder mark 1221 can be calculated. Then, according to Equation 7, the length L of the pole post assembly 120 is calculated. Then, according to the process described above, it is determined whether the length L of the pole post assembly 120 satisfies Equation 4. If it does not, the length A of the solder mark 1221 can be adjusted by adjusting the width W of the pole post assembly 120 and the width B of the solder mark 1221, thereby adjusting the length L of the pole post assembly 120. If the length L of the pole post assembly 120 satisfies Equation 4, it can be considered that the width W of the pole post assembly 120 meets the requirement of occupying less space, and the width B and length A of the solder mark 1221 meet the current carrying requirements of the riveting block 122.

[0086] It should be understood that if the width B of the solder mark 1221 is too large, the allowance between the edge of the pole assembly 120 and the solder mark 1221 will be small, affecting the structural strength of the pole assembly 120. If the width B of the solder mark 1221 is too small, the length of the solder mark 1221 will be too large (if the current requirement of the rivet block 122 is met), resulting in the flatness of the surface of the pole assembly 120 (i.e. the surface of the rivet block 122) not meeting the requirements, affecting the welding effect between the pole assembly 120 and the busbar (specifically, the rivet block 122 and the busbar).

[0087] Therefore, in this embodiment, the width B of the solder mark 1221 is limited to the following range: 2mm ≤ B ≤ 4mm. This effectively improves the problems caused by the aforementioned excessively large or small width B of the solder mark 1221.

[0088] In one embodiment, the width B of the solder mark 1221 can be selected as 2mm, 3mm, 4mm, etc.

[0089] It should be understood that if 'a' is too large, the distance between the two end pillars 1212 will be too large. After the pillars 1212 are riveted to the riveting block 122, the part of the riveting block 122 located between the two end pillars 1212 is prone to protrusion, which will cause the flatness of the surface of the riveting block 122 to fail to meet the requirements. If 'a' is too small, the solder mark 1221 will easily interfere with the pillars 1212. During the welding process, the pillars 1212 are easily affected by the welding.

[0090] Therefore, in this embodiment, 'a' is limited to the following range: 1mm ≤ a ≤ 2mm. This effectively improves the problems caused by 'a' being too large or too small.

[0091] In one embodiment, 'a' can be selected as 1mm, 1.5mm, 2mm, etc.

[0092] It should be understood that if d is too large, it will result in a large margin between the edge of the column 1212 and the rivet block 122, occupying a large space; if d is too small, it will result in a small margin between the edge of the column 1212 and the rivet block 122, affecting the overall structural strength of the pole post assembly 120.

[0093] Therefore, in this application embodiment, d is limited to the following range: 2mm ≤ d ≤ 3mm. This effectively improves the problems caused by d being too large or too small.

[0094] In one embodiment, d can be selected as 2mm, 2.5mm, or 3mm.

[0095] The present application will be further described below with reference to specific embodiments and comparative examples.

[0096] Example 1

[0097] The battery cell 200 includes a housing 210, an electrode assembly 220, and a cover plate assembly 100. The housing 210 has an opening, and the electrode assembly 220 extends into the housing 210 through the opening. The electrode assembly 220 has tabs 221. The cover plate assembly 100 is connected to the housing 210 and can close the opening of the housing 210. The cover plate assembly 100 is connected to the tabs 221.

[0098] The cover plate assembly 100 includes a cover plate 110 and a pole post assembly 120. The pole post assembly 120 includes a riveting block 122 and two pole posts 121. The two pole posts 121 are disposed on the cover plate 110. Each pole post 121 includes a base 1211 and a column 1212. One end of the column 1212 is connected to the base 1211. The bases 1211 of both pole posts 121 are electrically connected to the tabs 221. The two pole posts 121 are distributed along a first direction. The riveting block 122 is sleeved on the column 1212 of the two pole posts 121. The surface of the riveting block 122 is provided with a solder mark 1221 for connecting the busbar. The solder mark 1221 is located between the two columns 1212. The pole post assembly 120 is symmetrically arranged about a preset axis, the solder mark 1221 is symmetrically arranged about a preset axis, and the two pole posts 121 are symmetrically arranged about a preset axis.

[0099] The diameter of the connection between the column 1212 and the base 1211 is b; the length of the electrode assembly 120 along the first direction is L; the width of the electrode assembly 120 along the second direction is W; the length of the solder mark 1221 along the first direction is A; the width of the solder mark 1221 along the second direction is B; the distance between the edge of the connection between the column 1212 and the base 1211 and the edge of the solder mark 1221 along the first direction is a; the distance between the edge of the column 1212 and the edge of the riveting block 122 along the first direction is d; the capacity of the battery cell 200 is U; the charge / discharge rate of the battery cell 200 is C; the number of electrodes 121 is n; the overcurrent coefficient of the electrodes 121 is σ1; the overcurrent coefficient of the riveting block 122 is σ2; ​​and the effective coefficient of the solder mark 1221 is β. The above parameters satisfy:

[0100] W≥b+4;b≥ ;A≥UC / (Bσ2β);L=A+2(a+b+d).

[0101] In this embodiment, U=60Ah; C=2; σ1=σ2=6.5A / mm 2 ;β=0.6; B=2.5mm; A=12.31mm; n=2; b=3.43mm; a=1.5mm; d=2mm; L=26.17mm.

[0102] Example 2

[0103] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0104] U=60Ah; C=2.5; σ1=σ2=6.5A / mm 2 ; β=0.6; B=2.5mm; A=15.38mm; n=2; b=3.83mm; a=1.5mm; d=2mm; L=30.05mm.

[0105] Example 3

[0106] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0107] U=60Ah; C=3; σ1=σ2=6.5A / mm 2 ;β=0.6; B=2.5mm; A=18.46mm; n=2; b=4.20mm; a=1.5mm; d=3mm; L=35.86mm.

[0108] Example 4

[0109] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0110] U=90Ah; C=2.5; σ1=σ2=6.5A / mm 2 ; β=0.6; B=2.5mm; A=23.08mm; n=2; b=4.70mm; a=1.5mm; d=3mm; L=41.47mm.

[0111] Example 5

[0112] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0113] U=90Ah; C=3; σ1=σ2=6.5A / mm 2 ; β=0.6; B=2.5mm; A=27.69mm; n=2; b=5.14mm; a=1.5mm; d=3mm; L=46.98mm.

[0114] Example 6

[0115] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0116] U=90Ah; C=4; σ1=σ2=6.5A / mm 2; β=0.6; B=2.5mm; A=36.92mm; n=2; b=5.94mm; a=1.5mm; d=3mm; L=57.80mm.

[0117] Example 7

[0118] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0119] U=90Ah; C=3.5; σ1=σ2=6.5A / mm 2 ; β=0.8; B=3.5mm; A=17.31mm; n=2; b=5.56mm; a=1.5mm; d=3mm; L=37.42mm.

[0120] Example 8

[0121] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0122] U=120Ah; C=2; σ1=σ2=6.5A / mm 2 ;β=0.8; B=3.5mm; A=13.19mm; n=2; b=4.85mm; a=1.5mm; d=3mm; L=31.89mm.

[0123] Example 9

[0124] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0125] U=120Ah; C=2.5; σ1=σ2=6.5A / mm 2 ; β=0.8; B=3.5mm; A=16.48mm; n=2; b=5.42mm; a=1.5mm; d=3mm; L=36.33mm.

[0126] Example 10

[0127] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0128] U=120Ah; C=3; σ1=σ2=6.5A / mm 2 ; β=0.8; B=3.5mm; A=19.78mm; n=2; b=5.94mm; a=1.5mm; d=3mm; L=40.66mm.

[0129] Example 11

[0130] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0131] U=120Ah; C=3.5; σ1=σ2=6.5A / mm 2 ; β=0.8; B=3.5mm; A=23.08mm; n=2; b=6.42mm; a=1.5mm; d=3mm; L=44.91mm.

[0132] Example 12

[0133] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0134] U=120Ah; C=3.5; σ1=σ2=6.5A / mm 2 ; β=0.7; B=3mm; A=30.77mm; n=2; b=6.42mm; a=1.5mm; d=3mm; L=52.60mm.

[0135] Example 13

[0136] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0137] U=140Ah; C=3.5; σ1=σ2=6.5A / mm 2 ; β=0.7; B=3mm; A=35.90mm; n=2; b=6.93mm; a=1.5mm; d=3mm; L=58.76mm.

[0138] Example 14

[0139] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0140] U=140Ah; C=3.5; σ1=σ2=6.5A / mm 2 ; β=0.8; B=4mm; A=23.56mm; n=2; b=6.93mm; a=1.5mm; d=3mm; L=46.42mm.

[0141] Example 15

[0142] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0143] U=140Ah; C=3; σ1=σ2=6.5A / mm 2;β=0.7; B=2.7mm; A=34.19mm; n=2; b=6.42mm; a=1.5mm; d=3mm; L=56.02mm.

[0144] Example 16

[0145] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0146] U=150Ah; C=2; σ1=σ2=6.5A / mm 2 ;β=0.7; B=2.7mm; A=24.42mm; n=2; b=5.42mm; a=1.5mm; d=3mm; L=44.26mm.

[0147] Example 17

[0148] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0149] U=150Ah; C=2.5; σ1=σ2=6.5A / mm 2 ; β=0.7; B=2.7mm; A=30.53mm; n=2; b=6.06mm; a=1.5mm; d=3mm; L=51.65mm.

[0150] Example 18

[0151] This embodiment is basically the same as embodiment 1, except for some parameters. The relevant parameters in this embodiment are as follows:

[0152] U=150Ah; C=3.5; σ1=σ2=6.5A / mm 2 ; β=0.8; B=4mm; A=25.24mm; n=2; b=7.17mm; a=1.5mm; d=3mm; L=48.59mm.

[0153] Comparative Example 1

[0154] This comparative example is basically the same as Example 1, except for some parameters. The relevant parameters in this comparative example are as follows:

[0155] U=90Ah; C=4; σ1=σ2=6.5A / mm 2 ;β=0.6; B=2.3mm; A=40.13mm; n=2; b=5.94mm; a=1.5mm; d=3mm; L=61.01mm.

[0156] Comparative Example 2

[0157] This comparative example is basically the same as Example 1, except for some parameters. The relevant parameters in this comparative example are as follows:

[0158] U=120Ah; C=4; σ1=σ2=6.5A / mm 2 ;β=0.7; B=2.7mm; A=39.07mm; n=2; b=6.86mm; a=1.5mm; d=3mm; L=61.79mm.

[0159] Comparative Example 3

[0160] This comparative example is basically the same as Example 1, except for some parameters. The relevant parameters in this comparative example are as follows:

[0161] U=140Ah; C=3.5; σ1=σ2=6.5A / mm 2 ;β=0.7; B=2.7mm; A=39.89mm; n=2; b=6.93mm; a=1.5mm; d=3mm; L=62.74mm.

[0162] Comparative Example 4

[0163] This comparative example is basically the same as Example 1, except for some parameters. The relevant parameters in this comparative example are as follows:

[0164] U=150Ah; C=3.5; σ1=σ2=6.5A / mm 2 ; β=0.7; B=3mm; A=38.46mm; n=2; b=7.17mm; a=1.5mm; d=3mm; L=61.81mm.

[0165] Test results

[0166] The flatness of the surface of the pole assembly 120 (specifically the riveting block 122) was inspected, as well as the presence of any cold solder joints between the pole assembly 120 (specifically the riveting block 122) and the busbar were checked. The inspection results are shown in the table below.

[0167]

[0168]

[0169]

[0170]

[0171]

[0172] According to the table above, when the length L of the pole assembly is less than 60mm, the flatness of the surface of the pole assembly 120 (specifically, the riveting block 122) meets the requirements, and there is no incomplete welding between the surface of the pole assembly 120 (specifically, the riveting block 122) and the busbar, ensuring the welding effect between the pole assembly 120 (specifically, the riveting block 122) and the busbar. When the length L of the pole assembly is greater than 60mm, the flatness of the surface of the pole assembly 120 (specifically, the riveting block 122) does not meet the requirements, and there is incomplete welding between the surface of the pole assembly 120 (specifically, the riveting block 122) and the busbar, making it impossible to guarantee the welding effect between the pole assembly 120 (specifically, the riveting block 122) and the busbar.

[0173] This application embodiment also provides an electrical device that may include the battery cell 200 as described in the previous embodiment and has all the functions of the battery cell 200.

[0174] The beneficial effects of the electrical equipment provided in this application embodiment can be referred to the beneficial effects of the aforementioned battery cell 200.

[0175] In one embodiment, the electrical equipment may include automobiles, construction machinery, special equipment, etc.

[0176] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0177] The block diagrams of devices, apparatuses, devices, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0178] It should also be noted that in the apparatus, equipment, and methods of this application, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered as equivalent solutions of this application.

[0179] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0180] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A cover plate assembly, characterized in that, include: Cover plate; A terminal assembly includes a terminal and a rivet block. The terminal is disposed on the cover plate, and there are two terminals distributed along a first direction. Each terminal includes a base and a column body. One end of the column body is connected to the base, and the diameter of the connection between the column body and the base is b (in mm). The length of the terminal assembly along the first direction is L (in mm). The width of the terminal assembly along a second direction is W (in mm). The rivet block is sleeved on the two columns, and the surface of the rivet block has solder marks for connecting a busbar. The solder marks are located between the two columns. The first direction represents the length direction of the cover plate, and the second direction represents the width direction of the cover plate. Wherein, b, L, and W satisfy: W ≥ b + 4; b ≥ L < 60 mm; Wherein, U represents the capacity of the battery cell, in Ah; C represents the charge / discharge rate of the battery cell, in A / Ah; n represents the number of terminals; and σ1 represents the overcurrent coefficient of the terminal, in A / mm. 2 ; The pole post assembly is symmetrically arranged about a preset axis, the solder mark is symmetrically arranged about the preset axis, and the two pole posts are symmetrically arranged about the preset axis. The length of the solder mark along the first direction is A (mm), the width of the solder mark along the second direction is B (mm), the distance between the edge of the connection between the post and the base and the edge of the solder mark along the first direction is a (mm), and the distance between the edge of the post and the edge of the rivet block along the first direction is d (mm). The following conditions are met: A, B, a, and d. A≥UC / (Bσ2β); L=A+2(a+b+d); Wherein, σ2 represents the flow coefficient of the riveting block, with units of A / mm. 2 ; β represents the effective coefficient of the solder mark; B satisfies: 2mm≤B≤4mm; a satisfies: 1mm≤a≤2mm; d satisfies: 2mm≤d≤3mm; The flatness of the surface of the rivet block is P, in mm, and P satisfies: P < 0.4 mm.

2. The cover plate assembly according to claim 1, characterized in that, The cover plate assembly also includes: The first plastic part is sleeved on the two pillars. The first plastic part is provided with a receiving groove, and the riveting block is disposed in the receiving groove.

3. A battery cell, characterized in that, include: The casing has an opening; An electrode assembly is disposed within the housing, and the electrode assembly is provided with electrode tabs; The cover plate assembly as claimed in claim 1 or 2, wherein the cover plate is connected to the housing to close the opening; and the base is electrically connected to the tab.

4. An electrical appliance, characterized in that, include: The battery cell as described in claim 3.

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