Battery cover plate assembly, battery and power device

Abstract

The present application relates to the technical field of batteries. Disclosed are a battery cover plate assembly, a battery and a power device. The battery cover plate assembly comprises a cover plate body and a terminal post assembly. The cover plate body is provided with a mounting hole, and the terminal post assembly is arranged in the mounting hole; the terminal post assembly comprises a terminal post, a first insulating member and a support ring, wherein a support ring flange of the support ring is welded to the cover plate body; the width of fusion of a weld seam between the cover plate body and the support ring flange is E, and the depth of fusion of said weld seam is F, the area of the projection of the terminal post assembly in the direction of its thickness is S, the circumference of the support ring flange is S1, and the shear strength of the material selected for the support ring flange is τ; the thickness of the cover plate body is T; the distance between a first step of the mounting hole and the upper end face of the cover plate body is C; and the minimum horizontal distance between the center of the weld seam and the outer sidewall of the first insulating member is K. In the present application, making the depth and width of fusion of the welding between the terminal post assembly and the cover plate body meet preset conditions can improve the reliability of the weld seam, ensuring that the weld seam is less prone to damage, improving the safety of the battery.

Description

Battery cover plate assembly, battery and power device

[0001] Cross-reference to related applications

[0002] The present application claims priority to the Chinese patent application No. 202411367253.2, filed on September 29, 2024, and entitled "Battery cover plate assembly, battery and power device", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0003] The present application relates to the technical field of batteries, in particular to a battery cover plate assembly, a battery and a power device. BACKGROUND

[0004] The safety and reliability of lithium-ion batteries have always been the most important issue in the new energy industry.

[0005] In the battery cover plate assembly, the pole post and the cover plate are welded together, but the conventional welding method has poor welding reliability, and the weld is easily damaged, which can cause battery leakage and safety problems.

[0006] The safety of the battery is always the top priority. Therefore, the weld between the pole post and the cover plate needs to be improved. SUMMARY

[0007] Therefore, the present application provides a battery cover plate assembly, a battery and a power device to solve the problem of poor welding reliability between the pole post and the cover plate, and the weld is easily damaged, which can cause poor battery safety.

[0008] In a first aspect, the present application provides a battery cover plate assembly, comprising a cover plate body and a pole post assembly, the cover plate body is provided with a mounting hole, the mounting hole is a stepped hole, the mounting hole comprises a first step and a second step arranged in the first step; the pole post assembly is arranged in the mounting hole, the pole post assembly comprises a pole post, a first insulating member and a support ring arranged outside the pole post, the support ring comprises a support ring body and a support ring protruding edge extending outwardly from the support ring body; the support ring body and the pole post are connected in a spaced manner, the support ring protruding edge is arranged in the second step and welded with the cover plate body; the fusion width of the weld between the cover plate body and the support ring protruding edge is E, the unit is mm, the fusion depth of the weld is F, the unit is mm, and the following conditions are met: 13S / 6S1τ≤F≤T-C-0.5, 0.8≤E<2K-2.4,

[0009] wherein,

[0010] S is the area of the pole post assembly projected along its thickness direction, the unit is mm 2 ;

[0011] S1 is the circumference of the support ring protruding edge, the unit is mm;

[0012] τ is the shear strength of the material selected for the support ring protrusion, in MPa;

[0013] T is the thickness of the cover plate body, in mm;

[0014] C is the vertical distance between the plane along which the first step is located and the upper end surface of the cover plate body, in mm;

[0015] K is the minimum horizontal distance between the center of the weld and the outer sidewall of the first insulating piece, in mm.

[0016] Beneficial effects: By controlling the welding penetration and welding width between the pole post assembly and the cover plate body, the reliability of the weld can be improved, so that the weld is not easily damaged, and the safety performance of the battery is improved.

[0017] In an alternative embodiment, the thickness T of the cover plate body satisfies: 1.5≤T≤4.

[0018] In an alternative embodiment, the vertical distance C between the plane along which the first step of the mounting hole is located and the upper end surface of the cover plate body satisfies: 0.2≤C≤0.5T.

[0019] In an alternative embodiment, the vertical distance between the plane along which the second step is located and the lower end surface of the cover plate body is A, in mm, and satisfies: 0.7≤A≤0.8T.

[0020] In an alternative embodiment, the vertical distance between the plane along which the second step is located and the plane along which the first step is located is B, in mm, and satisfies: 0.8≤B≤0.8T, and A+B+C=T.

[0021] In an alternative embodiment, the wall thickness of the support ring protrusion is D, in mm, and satisfies: B-0.15≤D≤B+0.15.

[0022] In an alternative embodiment, the shear strength τ of the material selected for the support ring protrusion satisfies: τ≥30MPa.

[0023] In an alternative embodiment, the first insulating piece is injection molded between the pole post and the support ring to fixedly connect the pole post and the support ring.

[0024] In a second aspect, the application further provides a battery comprising a shell, a pole group and the battery cover plate assembly of any one of the above embodiments, the shell having a receiving cavity, the shell having an open end in communication with the receiving cavity; the pole group is arranged in the receiving cavity of the shell, the pole group comprising a pole lug; the battery cover plate assembly is arranged at the open end of the shell, encapsulating the pole group in the shell, and the pole post of the battery cover plate assembly is in conductive connection with the pole lug of the pole group.

[0025] Beneficial effects: because the battery comprises the battery cover plate assembly, it has the same effects as the battery cover plate assembly, which will not be repeated here.

[0026] In a third aspect, the application further provides a power device comprising the battery of the above embodiments.

[0027] Beneficial effects: because the power device comprises the battery, it has the same effects as the battery, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the specific embodiments of the application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0029] Fig. 1 is a structural schematic diagram of a battery cover plate assembly according to an embodiment of the application from a first perspective;

[0030] Fig. 2 is a structural schematic diagram of a cover plate body and an explosion-proof valve in the battery cover plate assembly shown in Fig. 1;

[0031] Fig. 3 is a top view of the battery cover plate assembly shown in Fig. 1;

[0032] Fig. 4 is a sectional view along A-A in Fig. 3;

[0033] Fig. 5 is a partial enlarged view of B in Fig. 4;

[0034] Fig. 6 is an exploded view of the battery cover plate assembly shown in Fig. 1;

[0035] Fig. 7 is a structural schematic diagram of a cover plate body in the battery cover plate assembly shown in Fig. 1 from a first perspective;

[0036] Fig. 8 is a structural schematic diagram of the cover plate body shown in Fig. 7 from a second perspective;

[0037] Fig. 9 is a top view of the cover plate body shown in Fig. 7;

[0038] Fig. 10 is a sectional view along C-C in Fig. 9;

[0039] Fig. 11 is an enlarged view of D in Fig. 10;

[0040] Fig. 12 is a structural schematic view of a support ring;

[0041] Fig. 13 is a top view of the support ring shown in Fig. 12;

[0042] Fig. 14 is a sectional view along E-E in Fig. 13;

[0043] Fig. 15 is a structural schematic view of a square pole;

[0044] Fig. 16 is an exploded structural schematic view of the square pole shown in Fig. 15.

[0045] Legend: 1, cover plate body; 101, mounting hole; 1011, first step; 1012, second step; 2, pole; 3, first insulating member; 4, support ring; 401, support ring body; 402, support ring flange; 5, second insulating member; 6, explosion-proof valve; 7, explosion-proof valve protection film; 8, sealing ring. DETAILED DESCRIPTION

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0047] The embodiments of the present application will be described below with reference to Figs. 1 to 16.

[0048] According to the embodiments of the present application, in a first aspect, a battery cover plate assembly is provided, which comprises a cover plate body 1 and a pole assembly. The cover plate body 1 is provided with a mounting hole 101, which is a stepped hole and comprises a first step 1011 and a second step 1012 arranged in the first step 1011; the pole assembly is arranged in the mounting hole 101; the pole assembly comprises a pole 2 and a first insulating member 3 and a support ring 4 arranged outside the pole 2. The support ring 4 comprises a support ring body 401 and a support ring flange 402 extending outwardly from the support ring body 401; the support ring body 401 is connected to the pole 2 at intervals, the support ring flange 402 is arranged at the second step 1012 and is welded to the cover plate body 1; the fusion width of the weld between the cover plate body 1 and the support ring flange 402 is E, in mm, the fusion depth of the weld is F, in mm, and satisfies: 13S / 6S1τ≤F≤T-C-0.5, 0.8≤E<2K-2.4,

[0049] wherein,

[0050] S is the area of the pole assembly projected along the thickness direction, in mm 2 ;

[0051] S1 is the circumference of the support ring protrusion 402, in mm;

[0052] τ is the shear strength of the material selected for the support ring protrusion 402, in MPa;

[0053] T is the thickness of the cover plate body 1, in mm;

[0054] C is the vertical distance from the plane along which the first step 1011 lies to the upper end surface of the cover plate body 1, in mm;

[0055] K is the minimum horizontal distance from the center of the weld to the outer sidewall of the first insulating member 3, in mm.

[0056] Specifically, the fusion width refers to the lateral width of the molten metal of the welding wire or electrode during welding. In the present embodiment, the fusion width refers to the lateral width of the molten cover plate body 1 during welding of the cover plate body 1 and the support ring protrusion 402. The fusion depth refers to the longitudinal depth of the molten metal of the welding wire or electrode during welding. In the present embodiment, the fusion depth refers to the longitudinal depth of the molten cover plate body 1 during welding of the cover plate body 1 and the support ring protrusion 402.

[0057] If the weld fusion depth F is too small, the weld strength will be insufficient; if the weld fusion depth F is too large, the cover plate body 1 support portion will be deformed greatly, affecting assembly of the second insulating member 5.

[0058] If the weld fusion width E is too small, the weld fusion width will be insufficient, and the weld will be prone to breaking during use, resulting in low reliability; if the weld fusion width E is too large, the first insulating member 3 will be partially melted, affecting assembly between the pole 2 and the support ring 4, and insulation failure between the pole 2 and the support ring 4 will be prone to occur, resulting in low reliability.

[0059] The present embodiment can improve the reliability of the weld by controlling the weld fusion depth F and the weld fusion width E between the pole assembly and the cover plate body 1, thereby preventing the weld from being easily damaged and improving the safety performance of the battery.

[0060] To control the size of the weld fusion width E and the size of the weld fusion depth F, factors such as voltage, current, and welding speed can be controlled, so that the size of the weld fusion width E and the size of the weld fusion depth F are controlled within the above-mentioned range.

[0061] For the orientation, specifically, in FIG. 2, the direction indicated by X is the length direction of the cover plate body 1, the direction indicated by Y is the width direction of the cover plate body 1, and the direction indicated by Z is the thickness direction of the cover plate body 1. When the pole is a circular structure, the X direction is the radial direction of the pole, and the Z direction is the axial direction of the pole.

[0062] Specifically, the shape of the support ring 4 is adapted to the shape of the pole, for a circular pole 2, the support ring 4 is a circular ring, the support ring body 401 extends in the axial direction, and the support ring flange 402 extends in the radial direction. When the support ring 4 and the cover plate body 1 are assembled, the support ring flange 402 is arranged in the second step 1012 of the mounting hole 101. When welding, the joint between the support ring flange 402 and the mounting hole 101 is welded. For a square pole, the support ring 4 is also a rectangular ring.

[0063] In some embodiments, the first insulating part 3 is formed by injection molding between the pole 2 and the support ring 4, and the pole 2 and the support ring 4 are fixedly connected. Specifically, after the pole 2 and the support ring 4 are assembled, injection molding is performed to form the first insulating part 3, and the pole 2 and the support ring 4 are fixedly connected as one body at the same time. The first insulating part 3 is annular in structure, and further, the first insulating part 3 includes a plastic ring.

[0064] The pole 2, the first insulating part 3, and the support ring 4 are integrally formed, and the pole assembly can form a separate piece, greatly improving the assembly efficiency between the pole 2 and the cover plate body 1.

[0065] In some embodiments, the thickness T of the cover plate body 1 satisfies: 1.5≤T≤4.

[0066] Controlling the thickness T of the cover plate body 1 within this range can ensure the strength of the cover plate body 1 and prevent deformation during welding.

[0067] In some embodiments, the vertical distance C between the first step 1011 of the mounting hole 101 and the upper end surface of the cover plate body 1 along the plane of X-Y satisfies: 0.2≤C≤0.5T.

[0068] If the vertical distance C between the first step 1011 of the mounting hole 101 and the upper end surface of the cover plate body 1 along the plane of X-Y is too small, the welding seam will protrude from the surface of the cover plate body 1, resulting in poor appearance. Since the thickness T of the cover plate body 1 is determined, if the vertical distance C between the first step 1011 of the mounting hole 101 and the upper end surface of the cover plate body 1 along the plane of X-Y is too large, the vertical distance A between the second step 1012 of the mounting hole 101 and the lower end surface of the cover plate body 1 along the plane of X-Y will be too small, resulting in insufficient strength of the cover plate body 1 to support the support ring 4.

[0069] In some embodiments, the vertical distance A between the second step 1012 of the mounting hole 101 and the lower end surface of the cover plate body 1 along the plane of X-Y is 0.7≤A≤0.8T, in mm.

[0070] The vertical distance A between the second step 1012 along the plane of X-Y and the lower end surface of the cover plate body 1 is too small, which will penetrate the cover plate body 1 during welding, causing the cover plate body 1 to leak or the supporting part of the cover plate body 1 to be deformed too much, affecting the assembly of the connecting piece. If the vertical distance A between the second step 1012 along the plane of X-Y and the lower end surface of the cover plate body 1 is too large, the welding thickness of the supporting ring 4 and the cover plate body 1 will be insufficient, resulting in low welding strength and low reliability of the cover plate body 1.

[0071] In some embodiments, the vertical distance B between the second step 1012 along the plane of X-Y and the plane of the first step 1011 along the plane of X-Y is in mm, and satisfies: 0.8≤B≤0.8T, A+B+C=T.

[0072] The vertical distance C between the first step 1011 along the plane of X-Y and the upper end surface of the cover plate body, the vertical distance B between the second step 1012 along the plane of X-Y and the plane of the first step 1011 along the plane of X-Y, and the vertical distance A between the second step 1012 along the plane of X-Y and the lower end surface of the cover plate body 1 are the thickness T of the cover plate body 1. If the vertical distance B between the second step 1012 along the plane of X-Y and the plane of the first step 1011 along the plane of X-Y is too small, the thickness of the supporting ring 4 will be low, the supporting ring 4 will be weak and easy to deform, and the reliability will be low. If the vertical distance B between the second step 1012 along the plane of X-Y and the plane of the first step 1011 along the plane of X-Y is too large, the thickness of the supporting ring 4 will be large, the supporting ring 4 will not be easy to be formed by stamping, and the processing cost will be high.

[0073] In some embodiments, the wall thickness of the supporting ring 4 is D in mm, and satisfies: B-0.15≤D≤B+0.15.

[0074] Controlling the wall thickness D of the supporting ring 4 within this range can improve the welding yield and avoid the occurrence of welding problems such as weld offset and burst point.

[0075] In some embodiments, the shear strength τ of the material selected for the supporting ring convex edge 402 satisfies: τ≥30Mpa, that is, the shear strength τ of the material selected for the supporting ring 4 satisfies: τ≥30MPa.

[0076] Controlling the shear strength τ of the material selected for the supporting ring 4 within the range of greater than or equal to 30MPa ensures that the supporting ring 4 has sufficient strength to pass the 1.3MPa pressure test of the battery.

[0077] In some embodiments, the battery cover plate assembly further comprises a second insulating piece 5 connected to one side of the cover plate body 1 facing the pole group.

[0078] In some embodiments, a sealing ring 8 is further included, and the sealing ring 8 is arranged between the pole post assembly and the mounting hole to achieve a sealed connection.

[0079] In some embodiments, the cover plate body 1 is provided with two mounting holes 101, and the pole post 2 includes a positive pole post and a negative pole post, and the two mounting holes 101 are respectively used for mounting the positive pole post and the negative pole post. The positive pole post and the negative pole post are of the same structure, and therefore, the connection structure between the positive pole post and the mounting hole 101 is the same as the connection structure between the negative pole post and the mounting hole 101.

[0080] In some embodiments, the cover plate body 1 is further provided with an explosion-proof valve 6, and the explosion-proof valve 6 is provided with an explosion-proof valve protection film 7.

[0081] Eight specific experimental cases are provided below. See Tables 1 to 8.

[0082] Table 1:

[0083] For the experimental cases 1 to 8 in Table 1, it is required that the fusion width E satisfies: 0.8≤E<2K-2.4, i.e., 0.8mm≤E<3.6mm.

[0084] For the experimental cases 1 to 6 and 8 in Table 1, it is required that the fusion depth F satisfies: 13S / 6S1τ≤F≤T-C-0.5, i.e., 0.26mm≤F≤1.3mm.

[0085] For the experimental case 7, it is required that the fusion depth F satisfies: 0.217mm≤F≤1.3mm.

[0086] As can be seen from Table 1, in the experimental case 1, the fusion width E=0.65mm is less than the lower limit value 0.8mm of E, the weld fusion width is insufficient, and the weld is prone to breakage during use, resulting in low reliability.

[0087] As can be seen from Table 1, in the experimental case 7, the fusion width E=3.6mm, and the value of 2K-2.4-E is zero, i.e., E is not less than the upper limit value 2K-2.4, the first insulating piece 3 appears to be partially melted, affecting the assembly between the pole post 2 and the support ring 4, and the insulation between the pole post 2 and the support ring 4 is prone to failure, resulting in low reliability.

[0088] As can be seen from Table 1, in the experimental case 3, the fusion depth F=0.1mm is less than the lower limit value 0.26mm of F, and the value of F-(13S) / (6S1τ) is negative, the 1.3MPa pressure test fails, and the weld strength is insufficient.

[0089] From Table 1, it can be seen that in the eighth implementation case, the penetration F = 1.5 mm, the value of T-C-0.5-F is negative, that is, F is greater than the upper limit value 1.3 mm, the penetration is deeper, and the support part of the cover plate body 1 is deformed greatly, which affects the assembly of the second insulating part 5.

[0090] Table 2:

[0091] For the ninth to sixteenth experimental cases in Table 2, it is required that the weld width E satisfies: 0.8≤E<2K-2.4, that is, 0.8mm≤E<3.6mm.

[0092] For the ninth to fourteenth and sixteenth experimental cases in Table 2, it is required that the penetration F satisfies: 13S / 6S1τ≤F≤T-C-0.5, that is, 0.26mm≤F≤0.8mm.

[0093] For the fifteenth experimental case, it is required that the penetration F satisfies: 0.217mm≤F≤0.8mm.

[0094] From Table 2, it can be seen that in the ninth implementation case, the weld width E = 0.65 mm is less than the lower limit value 0.8 mm of E, the weld width is insufficient, and the weld is prone to breakage during use, which has low reliability.

[0095] From Table 2, it can be seen that in the fifteenth implementation case, the weld width E = 3.6 mm, the value of 2K-2.4-E is zero, that is, E is not less than the upper limit value 2K-2.4, the first insulating part 3 is partially melted, which affects the assembly between the pole 2 and the support ring 4, and is prone to insulation failure between the pole 2 and the support ring 4, which has low reliability.

[0096] From Table 2, it can be seen that in the eleventh implementation case, the penetration F = 0.1 mm, the value of F-(13S) / (6S1τ) is negative, that is, F is less than the lower limit value 0.26 mm, and the 1.3 MPa pressure test fails, and the weld strength is insufficient.

[0097] From Table 2, it can be seen that in the sixteenth implementation case, the penetration F = 1 mm, the value of T-C-0.5-F is negative, that is, F is greater than the upper limit value 0.8 mm, the penetration is deeper, and the support part of the cover plate body 1 is deformed greatly, which affects the assembly of the second insulating part 5.

[0098] Table 3:

[0099] For the seventeenth to twenty-fourth experimental cases in Table 3, it is required that the weld width E satisfies: 0.8≤E<2K-2.4, that is, 0.8mm≤E<3.6mm.

[0100] For the implementation cases seventeen to twenty-two and twenty-four in Table Three, the fusion depth F is required to satisfy: 13S / 6S1τ≤F≤T-C-0.5, i.e., 0.26mm≤F≤2.3mm.

[0101] For the implementation case twenty-three, the fusion depth F is required to satisfy: 0.217mm≤F≤2.3mm.

[0102] As can be seen from Table Three, in the implementation case seventeen, the fusion width E=0.65mm, which is less than the lower limit value 0.8mm of E, the weld fusion width is insufficient, and the weld is prone to breakage during use, and the reliability is relatively low.

[0103] As can be seen from Table Three, in the implementation case twenty-three, the fusion width E=3.6mm, and the value of 2K-2.4-E is negative, i.e., E is not less than the upper limit value 2K-2.4, the first insulation piece 3 appears partial melting, which affects the assembly between the pole 2 and the support ring 4, and is prone to insulation failure between the pole 2 and the support ring 4, and the reliability is low.

[0104] As can be seen from Table Three, in the implementation case nineteen, the fusion depth F=0.1mm, and the value of F-(13S) / (6S1τ) is negative, i.e., F is less than the lower limit value 0.26mm, and the 1.3MPa pressure test fails, and the weld strength is insufficient.

[0105] As can be seen from Table Three, in the implementation case twenty-four, the fusion depth F=2.5mm, and the value of T-C-0.5-F is negative, i.e., F is greater than the upper limit value 2.3mm, the fusion depth is deep, and the support part of the cover plate body 1 is deformed greatly, which affects the assembly of the second insulation piece 5.

[0106] Table Four:

[0107] For the implementation cases twenty-five to thirty-two in Table Four, the fusion width E is required to satisfy: 0.8≤E<2K-2.4, i.e., 0.8mm≤E<3.6mm.

[0108] For the implementation cases twenty-five to thirty in Table Four and the implementation case thirty-two, the fusion depth F is required to satisfy: 13S / 6S1τ≤F≤T-C-0.5, i.e., 0.26mm≤F≤0.8mm.

[0109] For the implementation case thirty-one, the fusion depth F is required to satisfy: 0.217mm≤F≤0.8mm.

[0110] As can be seen from Table Four, in the implementation case twenty-five, the fusion width E=0.65mm, which is less than the lower limit value 0.8mm of E, the weld fusion width is insufficient, and the weld is prone to breakage during use, and the reliability is relatively low.

[0111] As can be seen from Table Four, in the thirty-first implementation case, the melt width E = 3.6 mm, the value of 2K-2.4-E is zero, that is, E is not less than the upper limit value 2K-2.4, resulting in partial melting of the first insulating member 3, affecting the assembly between the pole 2 and the support ring 4, and easily causing insulation failure between the pole 2 and the support ring 4, and low reliability.

[0112] As can be seen from Table Four, in the twenty-seventh implementation case, the melt depth F = 0.1 mm, the value of F-(13S) / (6S1τ) is negative, that is, F is less than the lower limit value 0.26 mm, resulting in failure in the 1.3 MPa pressure test, and insufficient weld strength.

[0113] As can be seen from Table Four, in the thirty-second implementation case, the melt depth F = 3.5 mm, the value of T-C-0.5-F is negative, that is, F is greater than the upper limit value 3.3 mm, the melt depth is deep, resulting in large deformation of the support part of the cover plate body 1, affecting the assembly of the second insulating member 5.

[0114] It can be concluded from Tables One to Four that controlling the melt depth F and the melt width E between the support ring 4 and the cover plate body 1 within the range of 13S / 6S1τ≤F≤T-C-0.5, 0.8≤E<2K-2.4 can ensure the strength of the weld, guarantee the stability of the welding between the pole 2 and the cover plate body 1, and improve the safety performance of the battery.

[0115] Table Five:

[0116] As can be seen from Table Five, in the thirty-fifth implementation case, the shear strength τ of the material selected for the support ring 4 is 10 MPa, which is lower than the lower limit value 30 MPa, the material shear strength of the support ring 4 is low, resulting in failure in the 1.3 MPa pressure test. In other implementation cases, τ≥30 MPa under the condition of ensuring that the melt depth F and the melt width E are within the limited range, and the 1.3 MPa pressure test is passed.

[0117] Table Six:

[0118] As can be seen from Table Six, in the forty-first implementation case, the shear strength τ of the material selected for the support ring 4 is 10 MPa, which is lower than the lower limit value 30 MPa, the material shear strength of the support ring 4 is low, resulting in failure in the 1.3 MPa pressure test. In other implementation cases, τ≥30 MPa under the condition of ensuring that the melt depth F and the melt width E are within the limited range, and the 1.3 MPa pressure test is passed.

[0119] Table Seven:

[0120] As can be seen from Table Seven, in the forty-seventh implementation case, the shear strength τ of the material selected for the support ring 4 is 10 MPa, which is lower than the lower limit value 30 MPa, and the shear strength of the material of the support ring 4 is low, resulting in that the 1.3 MPa pressure test fails. In other implementation cases, in the case of ensuring that the penetration F and the width E are within the limited range, τ≥30 MPa, and the 1.3 MPa pressure test passes.

[0121] Table Eight:

[0122] As can be seen from Table Eight, in the fifty-third implementation case, the shear strength τ of the material selected for the support ring 4 is 10 MPa, which is lower than the lower limit value 30 MPa, and the shear strength of the material of the support ring 4 is low, resulting in that the 1.3 MPa pressure test fails. In other implementation cases, in the case of ensuring that the penetration F and the width E are within the limited range, τ≥30 MPa, and the 1.3 MPa pressure test passes.

[0123] According to the embodiments of the present application, the second aspect further provides a battery including a shell pole group and the battery cover plate assembly in any one of the above embodiments. The shell has a containing cavity, and the shell has an open end in communication with the containing cavity; the pole group is arranged in the containing cavity of the shell, and the pole group includes a pole lug; the battery cover plate assembly is arranged at the open end of the shell, encapsulates the pole group in the shell, and the pole post 2 of the battery cover plate assembly is in conductive connection with the pole lug of the pole group.

[0124] Since the battery in the present embodiment includes the battery cover plate assembly in the above embodiments, all the beneficial effects of the battery cover plate assembly are possessed, which will not be described here again.

[0125] According to the embodiments of the present application, the third aspect further provides a power device including the battery in the above embodiments.

[0126] Since the power device in the present embodiment includes the battery in the above embodiments, the same beneficial effects as the battery are possessed, which will not be described here again.

[0127] Although the embodiments of the present application are described in conjunction with the drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.

Claims

1. A battery cover plate assembly, characterized by, The battery cover plate assembly comprises: a cover plate body provided with a mounting hole, the mounting hole being a stepped hole, the mounting hole comprising a first step and a second step arranged in the first step; a pole column assembly arranged in the mounting hole, the pole column assembly comprising a pole column, a first insulating member and a support ring arranged outside the pole column, the support ring comprising a support ring body and a support ring protruding edge extending outwardly from the support ring body, the support ring body being connected to the pole column at a distance, and the support ring protruding edge being arranged in the second step and welded to the cover plate body; a fusion width of a weld joint between the cover plate body and the support ring protruding edge being E, in mm, and a fusion depth of the weld joint being F, in mm, satisfying: 13S / 6S1τ≤F≤T-C-0.5, 0.8≤E<2K-2.4, wherein, S is the area of the pole assembly projected along its thickness direction in mm2 2 ; S1 is a circumference of the support ring protruding edge, in mm; τ is a shear strength of a material selected for the support ring protruding edge, in MPa; T is a thickness of the cover plate body, in mm; C is a vertical distance between a plane along which the first step extends and an upper end surface of the cover plate body, in mm; K is a minimum horizontal distance between a center of the weld joint and an outer sidewall of the first insulating member, in mm.

2. The battery cover plate assembly of claim 1, wherein, The thickness T of the cover plate body satisfies: 1.5≤T≤4.

3. The battery cover plate assembly of claim 1 or 2, wherein, The vertical distance C between a plane along which the first step of the mounting hole extends and an upper end surface of the cover plate body satisfies: 0.2≤C≤0.5T.

4. The battery cover plate assembly of claim 3, wherein, A vertical distance between a plane along which the second step extends and a lower end surface of the cover plate body satisfies: 0.7≤A≤0.8T.

5. The battery cover plate assembly of claim 4, wherein, A vertical distance between a plane along which the second step extends and a plane along which the first step extends satisfies: 0.8≤B≤0.8T, and A+B+C=T.

6. The battery cover plate assembly of claim 5, wherein, A wall thickness of the support ring protruding edge satisfies: B-0.15≤D≤B+0.

15.

7. The battery cover plate assembly of claim 1 or 2, wherein, The shear strength τ of the material selected for the support ring protruding edge satisfies: τ≥30MPa.

8. The battery cover plate assembly of claim 1 or 2, wherein, The first insulating member is formed by injection molding between the pole column and the support ring, and the pole column and the support ring are fixedly connected.

9. A battery, characterized by The battery cover plate assembly comprises: a shell having a receiving cavity, the shell having an open end communicating with the receiving cavity; a pole group arranged in the receiving cavity of the shell, the pole group comprising pole tabs; the battery cover plate assembly of any one of claims 1 to 8 is arranged at the open end of the shell, the pole group being encapsulated in the shell, and the pole column of the battery cover plate assembly and the pole tabs of the pole group are electrically connected.

10. A power plant characterized by The battery comprises the battery cover plate assembly of claim 9.

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