Battery

Abstract

The invention relates to the technical field of batteries, and particularly discloses a battery which comprises a cover plate body, a shell and a first plastic part, a first liquid injection hole is formed in the cover plate body or the shell, a second liquid injection hole and an annular flange are arranged on the first plastic part, the annular flange is arranged in the circumferential direction of the second liquid injection hole, and the second liquid injection hole is communicated with the first liquid injection hole. The end face, deviating from the cover plate body or the shell, of the annular flange is provided with a plurality of convex parts and a plurality of concave parts, and the convex parts and the concave parts are alternately arranged in the circumferential direction of the annular flange. During liquid injection or vacuum pumping, the convex part can be used for supporting an insulating adhesive tape wrapping the tab and the connecting piece, and a circulation space is formed between the concave part and the insulating adhesive tape, so that electrolyte can smoothly flow in the first liquid injection hole, the second liquid injection hole and the circulation space, the insulating adhesive tape is prevented from shielding the second liquid injection hole and the first liquid injection hole, the liquid injection efficiency is relatively high, and the service life of the electrolyte is prolonged. And vacuumizing is easy to realize.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a battery. Background Art

[0002] Common lithium-ion batteries currently generally include a battery cover plate, a lower plastic part, a pole group, a housing, etc. Among them, the pole group is arranged in the housing. After the battery cover plate and the housing are laser welded, a closed space for protecting the pole group is formed. The pole tabs of the pole group are electrically connected to the pole posts on the battery cover plate through conductive connecting pieces. The lower plastic part is arranged on one side of the battery cover plate and can press the pole group tightly in the housing to prevent the pole group from shaking and causing an internal short circuit. Liquid injection holes are provided on both the battery cover plate and the lower plastic part, and the electrolyte can be injected into the housing through the liquid injection holes so that the pole group is immersed in the electrolyte.

[0003] For some battery cover plates with smaller sizes or higher integration degrees, due to structural design and layout space limitations, the liquid injection holes can only be arranged above the pole tabs. The pole tabs and the pole posts are electrically connected through conductive connecting pieces. To prevent slag from falling off the welding marks of the welding between the pole tabs and the conductive connecting pieces and to prevent the pole tabs from making a lap short circuit with the housing, a high-temperature insulating tape is wrapped around the welding area between the pole tabs and the conductive connecting pieces. See Figure 1 , a conical flow guiding structure 12' is usually provided at the liquid injection hole 11' of the lower plastic part 10'. The flow guiding structure 12' is arranged circumferentially around the liquid injection hole 11' and is coaxial with the liquid injection hole 11'. The flow guiding structure 12' on the lower plastic part 10' is arranged above the connection area between the conductive connecting piece 20' and the pole tab. During the battery production process, when injecting liquid into the housing through the liquid injection hole 11' and performing a vacuum pumping operation, the high-temperature insulating tape 30' may adhere to the flow guiding structure 12', causing blockage of the liquid injection hole 11', slow liquid injection rate, and affecting production efficiency. Summary of the Invention

[0004] The object of the present invention is to provide a battery in which there is a flow-through space between the first plastic part and the insulating tape covering the outside of the pole tab and the connecting piece, and the electrolyte can be injected into the housing through the flow-through space, with smooth liquid injection and relatively high liquid injection efficiency and vacuum pumping efficiency.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention provides a battery, including:

[0007] A cover plate body;

[0008] A housing, connected to the cover plate body, the housing and the cover plate body jointly enclose a containing cavity, and one of the housing and the cover plate body is provided with a first liquid injection hole;

[0009] A first plastic part is arranged on a side of the cover body or the shell facing the accommodating cavity, a second injection hole and an annular flange are arranged on the first plastic part, the second injection hole is communicated with the first injection hole, and the annular flange is arranged around the circumference of the second injection hole; the end surface of the annular flange away from the cover body or the shell is wavy, and the end surface of the annular flange away from the cover body has a plurality of convex parts and a plurality of concave parts, the convex parts and the concave parts are alternately arranged in the circumference of the annular flange, the vertices of all the convex parts are located in a first reference plane parallel to the first plastic part, and the bottom points of all the concave parts are located in a second reference plane parallel to the first plastic part;

[0010] Wherein, along the axial direction of the second injection hole, the distance between the first reference plane and the second reference plane is a, and the distance between the end of the protrusion and the end surface of the first plastic part facing the accommodating cavity is F; a and F satisfy: 0.3≤a / F≤0.6;

[0011] The value range of a is 0.6mm≤a≤10mm.

[0012] Optionally, the diameter of the first injection hole is φD, the inner diameter of the end of the protrusion in the first reference plane is φE; φD and φE satisfy: 1.1≤φE / φD≤2.6;

[0013] a and φE satisfy: 0.15≤a / φE≤4;

[0014] The value range of φD is 2mm≤φD≤5mm.

[0015] Optionally, along the radial direction of the second liquid injection hole, the thickness of the annular flange is e, and the value range of e is 0.3mm≤e≤3.0mm.

[0016] Optionally, the battery includes a pole group, the first liquid injection hole is arranged on the cover body, and the first plastic part is arranged on a side of the cover body close to the pole group.

[0017] Optionally, the electrode group includes a pole ear and a connecting piece, the connecting piece is connected to the pole ear, the connecting piece is located on a side close to the first plastic part, and an end surface of the connecting piece facing away from the electrode group and an end surface close to the annular flange intersect to form an edge;

[0018] Along the radial direction of the second liquid injection hole, the distance between the outer peripheral wall of the annular flange away from the second liquid injection hole and the edge is b, and the value range of b is b≥0.1 mm.

[0019] Optionally, along the axial direction of the second liquid injection hole, the distance between the vertex of the protrusion and the end surface of the pole ear away from the pole group is h, and the value range of h is h≥0.1 mm.

[0020] Optionally, a guide flange is provided on the cover plate body, the guide flange is arranged in the circumference of the first injection hole, and the guide flange extends into the second injection hole.

[0021] Optionally, the annular flange is connected to the first plastic part via a first transition surface, the first transition surface faces the second injection hole, and the guide flange is connected to the cover body via a second transition surface, the second transition surface faces away from the first injection hole;

[0022] Along the radial direction of the second liquid injection hole, there is a gap C between the first transition surface and the second transition surface, and the value range of C is C≥0.1mm.

[0023] Optionally, within the curved surface where the outer peripheral wall of the annular flange on the side away from the second liquid injection hole is located, the cross-sectional area of the convex portion is equal to the cross-sectional area of the concave portion.

[0024] Optionally, the number of the convex portions is n, n≥3, and the flow area of the first injection hole is S;

[0025] Among them, the relationship between φE, a, S, and φD satisfies: (π·φE·a) / 2≥0.8S;

[0026]

[0027] The beneficial effects of the present invention are:

[0028] The present invention provides a battery, including a cover body, a shell and a first plastic part. The shell and the cover body together enclose a receiving cavity, the first plastic part is arranged on the side of the cover body or the shell facing the receiving cavity, and one of the shell and the cover body is provided with a first injection hole. The first plastic part is provided with a second injection hole and an annular flange, the annular flange is arranged around the circumference of the second injection hole, and the second injection hole is connected with the first injection hole. The end surface of the annular flange facing away from the cover body or the shell has a plurality of convex parts and a plurality of concave parts, and the convex parts and the concave parts are alternately arranged in the circumference of the annular flange. When injecting liquid or vacuuming, the convex part can be used to support the insulating tape wrapped around the outer surface of the pole ear and the connecting piece, and a circulation space is formed between the concave part and the insulating tape, thereby, the electrolyte can flow smoothly in the first injection hole, the second injection hole and the circulation space, avoiding the insulating tape blocking the second injection hole and the first injection hole, the injection efficiency is high, and vacuuming is easy to achieve. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1Schematic diagram of the structure of the battery cover plate, lower plastic part and electrode group in the prior art;

[0030] Figure 2 Schematic diagram of the structure of the cover plate body and the first plastic part provided in the first embodiment of the present invention;

[0031] Figure 3 For Figure 2 Partial enlarged view at position A in

[0032] Figure 4 Bottom view of the cover plate body and the first plastic part provided in the first embodiment of the present invention;

[0033] Figure 5 For Figure 4 Partial enlarged view at position B in

[0034] Figure 6 Partial sectional view of the battery provided in the first embodiment of the present invention;

[0035] Figure 7 For Figure 6 Partial enlarged view at position C in

[0036] In the figure:

[0037] 10’, lower plastic part; 11’, liquid injection hole; 12’, flow guiding structure; 20’, conductive connecting piece; ’30, high temperature insulating tape;

[0038] 100, cover plate body; 110, first liquid injection hole; 120, guiding flange; 1201, second transition surface; 200, first plastic part; 210, second liquid injection hole; 220, annular flange; 221, convex part; 222, concave part; 2201, first transition surface; 300, pole column; 400, second plastic part; 500, housing; 600, electrode group; 610, pole ear; 620, connecting piece; 621, edge; 630, insulating tape. Detailed implementation manners

[0039] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0040] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions. Moreover, the first feature being "above", "over" and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature has a higher horizontal height than the second feature. The first feature being "below", "under" and "beneath" the second feature includes the first feature being directly below and obliquely below the second feature, or simply indicating that the first feature has a lower horizontal height than the second feature.

[0041] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "mounted", "connected" and "coupled" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, in which the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation on the present invention.

[0043] Embodiment 1

[0044] As Figures 2 - 5 shown, this embodiment provides a battery, which includes a cover body 100, a housing 500, and a first plastic part 200. An opening is provided on one side of the housing 500. The cover body 100 is connected to the opening of the housing 500, and a receiving cavity for mounting the electrode group 600 is formed by jointly enclosing the housing 500 and the cover body 100.

[0045] Further, a first liquid injection hole 110 is provided on the cover plate body 100. The first plastic part 200 is arranged on the side of the cover plate body 100 facing the accommodating cavity. A second liquid injection hole 210 and an annular flange 220 are provided on the first plastic part 200. The second liquid injection hole 210 communicates with the first liquid injection hole 110. The annular flange 220 is arranged around the circumference of the second liquid injection hole 210. The end face of the annular flange 220 facing away from the cover plate body 100 is wavy. The end face of the annular flange 220 facing away from the cover plate body 100 has a plurality of convex portions 221 and a plurality of concave portions 222. The convex portions 221 and the concave portions 222 are alternately arranged in the circumferential direction of the annular flange 220, and the convex portions 221 and the concave portions 222 are smoothly transitioned. The vertices of all the convex portions 221 are located in a first reference plane parallel to the first plastic part 200, and the bottom points of all the concave portions 222 are located in a second reference plane parallel to the first plastic part 200. It should be noted that the vertices of all the convex portions 221 are the outermost ends of the annular flange 220 on the side facing away from the cover plate body 100. When injecting liquid or evacuating, the convex portions 221 can be used to support the insulating tape 630 covering the tab 610 and the connecting piece 620. A flow space is formed between the concave portions 222 and the insulating tape 630. Thus, the electrolyte can flow smoothly in the first liquid injection hole 110, the second liquid injection hole 210, and the flow space, avoiding the insulating tape 630 from blocking the second liquid injection hole 210 and the first liquid injection hole 110, with a high liquid injection efficiency and easy evacuation.

[0046] See Figure 6 and Figure 7 , along the axial direction of the second liquid injection hole 210 (i.e., Figure 6 the Z-axis direction shown in

[0047] ), the distance between the first reference plane and the second reference plane is a, and the distance between the end of the convex portion 221 and the end face of the first plastic part 200 facing the accommodating cavity is F; the relationship between a and F satisfies: 0.3 ≤ a / F ≤ 0.6. Exemplarily, the value of a / F can be 0.3, 0.4, 0.5, or 0.6, etc. By controlling the value of a / F within the above range, on the one hand, it is convenient to process the convex portions 221 and the concave portions 222 on the end face of the annular flange 220 facing away from the cover plate body 100, with a high forming rate and product yield; on the other hand, it is also to form a larger flow space between the concave portions 222 and the insulating tape 630 to facilitate the rapid flow of the electrolyte.Optionally, the value range of a is 0.6 mm ≤ a ≤ 10 mm. For example, the value of a can be 0.6 mm, 0.8 mm, 1.0 mm, 2.0 mm, 4.0 mm, 5.0 mm, 10.0 mm, etc. When the value of a is 0.6 mm, the value of F can be 1.0 mm, 1.2 mm, 1.5 mm, 2.0 mm, etc. When the value of a is 5.0 mm, the value of F can be 8.5 mm, 10.0 mm, 12.5 mm, 16.0 mm. When the value of a is 10.0 mm, the value of F can be 17 mm, 20.0 mm, 25.0 mm, 32.0 mm, etc. The distance a between the first reference plane and the second reference plane is also the dimension of the convex portion 221 along the axial direction of the second liquid injection hole 210, and the dimension of the concave portion 222 along the axial direction of the second liquid injection hole 210. By limiting the dimension of a within the above range, the convex portion 221 can well support the insulating tape 630, preventing the insulating tape 630 from covering the second liquid injection hole 210 and the first liquid injection hole 110 during vacuum pumping. At the same time, a relatively large flow space can be formed between the concave portion 222 and the insulating tape 630 to facilitate the flow of electrolyte or gas. Otherwise, if the value of a is too small, the convex portion 221 cannot well support the insulating tape 630. After the insulating tape 630 bulges toward the cover body 100, it may fit into the concave portion 222 of the annular flange 220, completely covering the flow space and causing poor vacuum pumping. The value of a should not be too large either. Otherwise, it is necessary to correspondingly increase the dimension of the annular flange 220 along the axial direction of the second liquid injection hole 210, occupying a large space and being unfavorable for improving the energy density of the battery. In addition, when the number of the convex portions 221 and the concave portions 222 is large, the transition between the convex portions 221 and the concave portions 222 is relatively drastic, making it difficult to process and manufacture. Moreover, the convex portions 221 are relatively sharp, easily damaging the insulating tape 630 and having a short-circuit risk.

[0048] Continue to refer to Figure 5 , in this embodiment, the diameter of the first liquid injection hole 110 is φD, and the value range of φD is 2 mm ≤ φD ≤ 5 mm. For example, the value of φD can be 2 mm, 3 mm, 4 mm, or 5 mm. Controlling the diameter φD of the first liquid injection hole 110 within the above range is to ensure that the flow area of the first liquid injection hole 110 is large enough during liquid injection or vacuum pumping to meet the usage requirements of liquid injection and vacuum pumping. In addition, the annular flange 220 in this embodiment is in an inverted cone shape, with its small end facing away from the cover body 100. The inverted cone-shaped annular flange 220 has a certain guiding effect, facilitating the injection of electrolyte.

[0049] The inner diameter of the end of the convex portion 221 in the first reference plane is φE, that is, the minimum inner diameter of the annular flange 220 is φE. The relationship between φD and φE satisfies: 1.1 ≤ φE / φD ≤ 2.6. For example, the value of φE / φD can be 1.1, 1.3, 1.5, 1.8, 2.0, 2.3, 2.6, etc. That is to say, the minimum inner diameter φE of the annular flange 220 is 1.1 to 2.6 times the diameter φD of the first liquid injection hole 110, and φE > φD, thereby ensuring the smooth installation of the liquid injection plug, and the liquid injection plug has a certain expansion space after passing through the annular flange 220, ensuring good sealing.

[0050] Furthermore, the relationship between a and φE also needs to satisfy: 0.15 ≤ a / φE ≤ 4. Exemplarily, the value of a / φE can be 0.15, 0.2, 0.5, 0.8, 0.9, 1.0, 2.0, 3.0, 4.0, etc. By controlling the value of a / φE within the above range, it is ensured that the ratio between a and φE is appropriate, avoiding the inner diameter φE of the end of the convex portion 221 in the first reference plane being too large while the value of a is too small (that is, the value of a / φE is too small), resulting in the insulating tape 630 bulging towards the cover plate body 100 and adhering to the concave portion 222 of the annular flange 220 when evacuating, blocking the flow space and making it difficult to evacuate. Of course, the value of a / φE should not be too large either, otherwise it is necessary to correspondingly increase the size of the annular flange 220 in the axial direction of the second liquid injection hole 210, occupying a large space and being not conducive to improving the energy density of the battery.

[0051] Continue to refer to Figure 6 and Figure 7 , along the radial direction of the second liquid injection hole 210 ( Figure 6 the Y-axis direction shown in

[0052] ), the thickness of the annular flange 220 is e, and the value range of e is 0.3 mm ≤ e ≤ 3.0 mm. Exemplarily, the value of e can be 0.3 mm, 0.5 mm, 1.5 mm, 2.5 mm, 3.0 mm, etc., and will not be listed one by one here. By setting the value of e to be greater than 0.3 mm, it is to make the annular flange 220 have a certain thickness, so that the contact area between its convex portion 221 and the insulating tape 630 is larger, avoiding the convex portion 221 being too sharp and piercing the insulating tape 630, and then scratching the tab 610. However, the value of e should not be too large either, otherwise shrinkage deformation will occur during the injection molding of the first plastic part 200, and the size of the first plastic part 200 is not standard, affecting the assembly accuracy between the cover plate body 100 and the first plastic part 200.Further, a pole group 600 is provided on the side of the first plastic part 200 facing away from the cover plate body 100. The pole group 600 is inserted into the accommodating cavity through an opening on one side of the housing 500. The pole group 600 includes pole lugs 610 and connecting pieces 620. The connecting pieces 620 are located on the side close to the first plastic part 200. One end of the connecting piece 620 is welded to the pole lug 610, and the other end of the connecting piece 620 is connected to the pole column 300 on the cover plate body 100. An insulating tape 630 is wrapped outside the connecting piece 620 and the pole lug 610. Along the axial direction of the second liquid injection hole 210, the projection of the insulating tape 630 on the first plastic part 200 can cover the second liquid injection hole 210. The insulating tape 630 can prevent slag from falling off the welding mark after the connecting piece 620 and the pole lug 610 are welded, and at the same time ensure good insulation between the connecting piece 620 and the cover plate body 100, as well as good insulation between the pole lug 610 and the cover plate body 100. Optionally, a second plastic part 400, a connecting block 410 and a pole column 300 are also integrated on the cover plate body 100. The second plastic part 400 is arranged on the side of the cover plate body 100 facing away from the pole group 600. The connecting block 410 is located on the side of the second plastic part 400 facing away from the pole group 600 and is embedded in the accommodating groove of the second plastic part 400. The pole column 300 passes through the first plastic part 200, the cover plate body 100, the second plastic part 400 and the connecting block 410 and is riveted to the connecting block 410. The second plastic part 400 is clamped between the connecting block 410 and the cover plate body 100. The arrangement of the second plastic part 400 can ensure insulation between the connecting block 410 and the cover plate body 100, and further ensure insulation between the pole column 300 and the end face of the cover plate body 100 on the side facing away from the pole group 600.

[0053] Further, an edge 621 is formed at the intersection of the end face of the connecting piece 620 facing away from the pole group 600 and the end face close to the annular flange 220. Along the radial direction of the second liquid injection hole 210, the distance between the outer peripheral wall of the annular flange 220 facing away from the second liquid injection hole 210 and the edge 621 is b, and the value range of b is b≥0.1mm. It should be noted that b is the minimum distance between the annular flange 220 and the connecting piece 620. Exemplarily, the value of b can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm or 0.6mm, etc., which will not be listed one by one here. The above setting can ensure that there is enough assembly clearance between the connecting piece 620 and the first plastic part 200 to accommodate the insulating tape 630, and avoid interference between the two when the assembly clearance between the two is insufficient. The insulating tape 630 is extruded and worn during long-term use, which may cause the insulating tape 630 to rupture, and further lead to a short-circuit risk.

[0054] Continue to refer to Figure 7, along the axial direction of the second injection hole 210, the spacing between the vertex of the protrusion 221 and the end face of the pole ear 610 away from the pole group 600 is h, that is, the spacing between the end of the annular flange 220 close to the pole group 600 and the end face of the pole ear 610 away from the pole group 600 is h, and the value range of h is: h≥0.1mm. Exemplarily, the value of h can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm or 0.6mm, etc., which are not listed here one by one. The above-mentioned setting can ensure that there is enough assembly clearance between the annular flange 220 and the pole ear 610 to accommodate the insulating tape 630, so as to avoid interference between the two when the assembly clearance between the two is insufficient, and the insulating tape 630 is squeezed and worn during long-term use, which may cause the insulating tape 630 to rupture, thereby causing the risk of short circuit.

[0055] Optionally, the cover body 100 is further provided with a guide flange 120, which is arranged in the circumference of the first injection hole 110, and extends toward the side where the first plastic part 200 is located and extends into the second injection hole 210. Through the cooperation between the guide flange 120 and the annular flange 220, the cover body 100 and the first plastic part 200 are accurately positioned and the installation accuracy is high. Furthermore, the annular flange 220 and the first plastic part 200 are connected through the first transition surface 2201, and the first transition surface 2201 faces the second injection hole 210. The first transition surface 2201 is a part of a torus, wherein the torus is a doughnut-shaped rotational curved surface generated by a circle rotating around an axis coplanar with the circle. By adopting the above configuration of the first transition surface 2201, a smooth transition is made between the end surface of the first plastic part 200 away from the pole group 600 and the inner wall of the annular flange 220 facing the second injection hole 210, thereby avoiding the connection between the first plastic part 200 and the annular flange 220 being too sharp, which is conducive to protecting the guide flange 120 from damage. The guide flange 120 is connected to the cover body 100 through the second transition surface 1201, and the second transition surface 1201 is away from the first injection hole 110. The second transition surface 1201 is a part of a conical surface, thereby enabling the guide flange 120 to cooperate with the first transition surface 2201 of the annular flange 220, and play a good guiding role when being installed in the second injection hole 210.

[0056] Along the radial direction of the second injection hole 210, there is a gap C between the first transition surface 2201 and the second transition surface 1201, and the value range of C is C ≥ 0.1mm. Exemplarily, the value of C can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm or 0.6mm, etc., which are not listed here one by one. The above setting can ensure that there is sufficient assembly gap between the cover body 100 and the first plastic part 200, avoiding interference caused by insufficient assembly gap between the two, resulting in poor assembly of the cover body 100 and the first plastic part 200, which may affect the sealing of the battery later.

[0057] Furthermore, in the curved surface where the outer peripheral wall of the annular flange 220 on the side away from the second injection hole 210 is located, the cross-sectional area of the convex portion 221 is equal to the cross-sectional area of the concave portion 222. That is, in the circumferential direction of the annular flange 220, the surface area of the outer peripheral wall of the annular flange 220 on the side away from the second injection hole 210 between the first reference plane and the second reference plane is S1, and the flow area of the flow space formed between the concave portion 222 and the first reference plane is S2, and S2 is half of S1.

[0058] Optionally, the number of the protrusions 221 is n, and the flow area of the first injection hole 110 is S;

[0059] Among them, the relationship between φE, a, S, and φD satisfies: (π·φE·a) / 2≥0.8S;

[0060]

[0061] In this embodiment, the number of convex parts 221 is 6 for illustration. Since the cross-sectional area of the convex part 221 is equal to the cross-sectional area of the concave part 222 in the curved surface where the outer peripheral wall of the annular flange 220 is away from the second liquid injection hole 210, when the end surface of the annular flange 220 away from the cover body 100 abuts against the insulating tape 630, the flow area of the flow space enclosed by the concave part 222 and the insulating tape 630 is S2, S2 = (π·φE·a) / 2.

[0062] In order to ensure that the flow area of the flow space enclosed by the concave portion 222 and the insulating tape 630 matches the flow area of the first injection hole 110, it is necessary to ensure that (π·φE·a) / 2≥0.8S. At this time, the flow rate of the injected electrolyte is relatively large, and no liquid will bubble up during rapid injection, thus meeting the circulation requirements of the electrolyte.

[0063] Of course, in other embodiments, the number of the convex portions 221 may also be set to 3, 4, 5, etc., which will not be elaborated one by one here. However, no matter how many the convex portions 221 are, the flow area S2 of the flow space formed between the concave portion 222 and the insulating tape 630 accounts for half of the surface area S1 of the outer peripheral wall of the annular flange 220 facing away from the second liquid injection hole 210 between the first reference plane and the second reference plane, and S1 = π·φE·a.

[0064] The following uses the batteries in some specific embodiments to verify the above size limitations. Samples of the annular flange 220 of the first plastic part 200 in the battery are made with different size parameters. Then, each cover body 100 and the housing 500 are assembled to form a battery, and each battery is tested for liquid injection and vacuum pumping. The results are shown in Table 1.

[0065] Table 1

[0066]

[0067] From the above results, it can be seen that in Embodiment 1, the value of parameter a is at the lower limit of its size limitation, the value of a / F is at the upper limit of its size limitation, and the remaining parameters are all normally taken, slightly higher than the lower limit of their corresponding size limitations. At this time, the insulating tape 630 does not block the second liquid injection hole 210 and the first liquid injection hole 110, and the liquid injection and vacuum pumping are both relatively smooth.

[0068] In Embodiment 2, the value of parameter a is at the upper limit of its size limitation, the value of a / F is close to the upper limit of its size limitation, and the remaining parameters are all normally taken, slightly higher than the lower limit of their corresponding size limitations. At this time, the insulating tape 630 does not block the second liquid injection hole 210 and the first liquid injection hole 110, and the liquid injection and vacuum pumping are both relatively smooth.

[0069] In Embodiment 3, the value of parameter a / φE is close to the lower limit of its size limitation, and the remaining parameters are all normally taken, slightly higher than the lower limit of their corresponding size limitations. At this time, the insulating tape 630 does not block the second liquid injection hole 210 and the first liquid injection hole 110, and the liquid injection and vacuum pumping are both relatively smooth.

[0070] In Embodiment 4, the value of parameter a / φE is at the lower limit of its size limitation, the value of a / F is at the lower limit of its size limitation, and the remaining parameters are all normally taken, slightly higher than the lower limit of their corresponding size limitations. At this time, the insulating tape 630 does not block the second liquid injection hole 210 and the first liquid injection hole 110, and the liquid injection and vacuum pumping are both relatively smooth.

[0071] In Embodiment 6, parameter (π·φE·a) / 2 = 0.8S. At this time, the insulating tape 630 does not block the second liquid injection hole 210 and the first liquid injection hole 110, and the liquid injection and vacuum pumping are both relatively smooth.

[0072] In Example 7, the value of the parameter (π·φE·a) / 2 is relatively close to the value of 0.8S, and the other parameters are all normally valued. At this time, the insulating tape 630 does not block the second liquid injection hole 210 and the first liquid injection hole 110, and the liquid injection and vacuum pumping are both relatively smooth, and the assembly efficiency is relatively high.

[0073] In Examples 5 and 8, all the parameters are normally valued, slightly higher than the lower limit of their corresponding dimensional limits. At this time, the insulating tape 630 does not block the second liquid injection hole 210 and the first liquid injection hole 110, and the liquid injection and vacuum pumping are both relatively smooth, and the assembly efficiency is relatively high.

[0074] Referring to Comparative Example 1, the value of the parameter a exceeds the lower limit of 0.6mm ≤ a ≤ 10mm, and the value of a / F exceeds the upper limit of 0.3 ≤ a / F ≤ 0.6, and the other parameters are all normally valued. At this time, when the production line performs the vacuum pumping operation, the insulating tape 630 significantly blocks the second liquid injection hole 210, the vacuum pumping is difficult, the production is delayed, and the assembly efficiency is reduced.

[0075] Referring to Comparative Example 2, the value of the parameter a / φE exceeds the lower limit of 0.15 ≤ a / φE ≤ 4, and the value of a / F exceeds the lower limit of 0.3 ≤ a / F ≤ 0.6, and the other parameters are all normally valued. At this time, the insulating tape 630 significantly blocks the second liquid injection hole 210, the vacuum pumping is difficult, the production is delayed, and the assembly efficiency is reduced.

[0076] Referring to Comparative Example 3, the value of the parameter a / φE exceeds the lower limit of 0.15 ≤ a / φE ≤ 4, the value of a / F is at the upper limit of 0.3 ≤ a / F ≤ 0.6, and the other parameters are all normally valued. At this time, the insulating tape 630 significantly blocks the second liquid injection hole 210, the vacuum pumping is difficult, the production is delayed, and the assembly efficiency is reduced.

[0077] Referring to Comparative Example 4, the parameter (π·φE·a) / 2 < 0.8S. At this time, the flow space formed between the concave portion 222 on the first plastic part 200 and the insulating tape 630 is small, and there is a liquid overflow phenomenon during liquid injection, the liquid injection is not smooth, which affects the production rhythm, and the assembly efficiency is reduced.

[0078] In summary, it can be known that when the above parameters φD, φE, a, a / φE, 0.8S, and (π·φE·a) / 2 are all within their corresponding dimensional limits, it can be ensured that the insulating tape 630 does not block the second liquid injection hole 210, and there is sufficient flow space between the insulating tape 630 and the concave portion 222 of the first plastic part 200, the liquid injection and vacuum pumping are smooth, and the assembly efficiency is relatively high.

[0079] Example Two

[0080] This embodiment also provides a battery, which is different from the battery in Embodiment 1 in that: in this embodiment, the first liquid injection hole 110 is provided on the housing 500, the first plastic part 200 is arranged on the side of the housing 500 facing the accommodating cavity, the first plastic part 200 is clamped between the housing 500 and the electrode group 600, and the second liquid injection hole 210 on the first plastic part 200 is communicated with the first liquid injection hole 110 on the housing 500. The structure of the first plastic part 200 is the same as that in Embodiment 1. By adopting the above-mentioned first plastic part 200, it can ensure the smooth progress of battery liquid injection or vacuum pumping, avoid the situation that the insulating tape 630 blocks the second liquid injection hole 210 and the first liquid injection hole 110, helps to quickly inject the electrolyte, and quickly pump the vacuum, with relatively high efficiency.

[0081] The rest of the structures in this embodiment are the same as those in Embodiment 1, and will not be described in detail here one by one.

[0082] Obviously, the above are only the preferred embodiments of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments here, and various obvious changes, re-adjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments only. Without departing from the concept of the present invention, it can also include more other equivalent embodiments, and the scope of the present invention is determined by the scope of the appended claims.

[0083] Note that in the description of this specification, the descriptions referring to the terms "some embodiments", "other embodiments", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

Claims

1. A battery, characterized in that, include: Cover plate body; A shell connected to the cover body, the shell and the cover body together enclose a containing cavity, and one of the shell and the cover body is provided with a first liquid injection hole; A first plastic part is arranged on a side of the cover body or the shell facing the accommodating cavity, a second injection hole and an annular flange are arranged on the first plastic part, the second injection hole is communicated with the first injection hole, and the annular flange is arranged around the circumference of the second injection hole; the end surface of the annular flange away from the cover body or the shell is wavy, and the end surface of the annular flange away from the cover body has a plurality of convex parts and a plurality of concave parts, the convex parts and the concave parts are alternately arranged in the circumference of the annular flange, the vertices of all the convex parts are located in a first reference plane parallel to the first plastic part, and the bottom points of all the concave parts are located in a second reference plane parallel to the first plastic part; Wherein, along the axial direction of the second injection hole, the distance between the first reference plane and the second reference plane is a, and the distance between the end of the protrusion and the end surface of the first plastic part facing the accommodating cavity is F; a and F satisfy: 0.3≤a / F≤0.6; The value range of a is: 0.6mm≤a≤10mm.

2. The battery according to claim 1, wherein The diameter of the first injection hole is φD, and the inner diameter of the end of the protrusion in the first reference plane is φE; φD and φE satisfy: 1.1≤φE / φD≤2.6; a and φE satisfy: 0.15≤a / φE≤4; The value range of φD is 2mm≤φD≤5mm.

3. The battery according to claim 1, wherein, Along the radial direction of the second liquid injection hole, the thickness of the annular flange is e, and the value range of e is 0.3mm≤e≤3.0mm.

4. The battery according to claim 1, wherein, The battery includes a pole group, the first liquid injection hole is arranged on the cover body, and the first plastic part is arranged on a side of the cover body close to the pole group.

5. The battery according to claim 4, characterized in that, The electrode group includes an electrode ear and a connecting piece, the connecting piece is connected to the electrode ear, the connecting piece is located on a side close to the first plastic part, and an end surface of the connecting piece facing away from the electrode group and an end surface close to the annular flange intersect to form an edge; Along the radial direction of the second liquid injection hole, the distance between the outer peripheral wall of the annular flange away from the second liquid injection hole and the edge is b, and the value range of b is b≥0.1 mm.

6. The battery according to claim 5, characterized in that, Along the axial direction of the second liquid injection hole, the distance between the vertex of the protrusion and the end surface of the pole ear away from the pole group is h, and the value range of h is h≥0.1 mm.

7. The battery according to claim 4, characterized in that, The cover plate body is provided with a guide flange, the guide flange is arranged in the circumference of the first liquid injection hole, and the guide flange extends into the second liquid injection hole.

8. The battery according to claim 7, wherein The annular flange is connected to the first plastic part via a first transition surface, the first transition surface faces the second injection hole, and the guide flange is connected to the cover body via a second transition surface, the second transition surface faces away from the first injection hole; Along the radial direction of the second liquid injection hole, there is a gap C between the first transition surface and the second transition surface, and the value range of C is C≥0.1mm.

9. The battery according to claim 1, characterized in that, In the curved surface where the outer peripheral wall of the annular flange on the side away from the second liquid injection hole is located, the cross-sectional area of the convex portion is equal to the cross-sectional area of the concave portion.

10. The battery according to claim 9, characterized in that, The number of the convex parts is n, n≥3, and the flow area of the first injection hole is S; Among them, the relationship between φE, a, S, and φD satisfies: (π·φE·a) / 2≥0.8S;

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