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, one of the cover plate body and the shell is provided with a first liquid injection hole, and the first liquid injection hole is communicated with a second liquid injection hole in the first plastic part. A first annular step of the flow guide supporting structure is arranged in the circumferential direction of a second liquid injection hole, a second annular step is connected to the side, close to the second liquid injection hole, of the first annular step, a through hole is formed in the first annular step, and the space, away from one side of the cover plate body or the shell, of the flow guide supporting structure communicates with the second liquid injection hole through the through hole. During liquid injection, electrolyte is injected into the containing cavity through the first liquid injection hole, the second liquid injection hole and / or the through hole, the electrolyte flows smoothly, and the liquid injection efficiency is high. During vacuumizing, the end face, facing one side of the pole group, of the second annular step can support the insulated rubber tape, gas is discharged through the through hole, the second liquid injection hole and the first liquid injection hole, vacuumizing is easy to achieve, and vacuumizing efficiency is high.

Description

Technical Field

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

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

[0003] However, for some battery cover plates with smaller sizes or higher integration levels, due to structural design and layout space limitations, the liquid injection holes can only be arranged above the tabs. The tab and the pole column are electrically connected through a conductive connection piece. To prevent slag from falling off the welding mark of the tab and the conductive connection piece and to prevent the tab from making lap contact short circuit with the housing, a high-temperature insulating tape is wrapped around the welding area of the tab and the conductive connection piece. A conical flow guiding structure is usually provided at the liquid injection hole of the lower plastic part, and the flow guiding structure on the lower plastic part is arranged above the connection area of the conductive connection piece and the tab. During the battery production process, when injecting liquid into the housing through the liquid injection hole and performing a vacuum pumping operation, the high-temperature insulating tape may adhere to the flow guiding structure, blocking the liquid injection hole, slowing down the liquid injection rate, and affecting the production efficiency. Summary of the Invention

[0004] The purpose of the present invention is to provide a battery, in which the electrolyte can smoothly enter the housing, the liquid injection efficiency is relatively high, and the insulating tape does not block the liquid injection hole, making the vacuum pumping easier and the vacuum pumping efficiency high.

[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, arranged on the side of the cover plate body or the housing facing the containing cavity, the first plastic part is provided with a second liquid injection hole, and the second liquid injection hole is communicated with the first liquid injection hole;

[0010] The diversion support structure includes a first annular step and a second annular step parallel to the first plastic part. The first annular step is disposed around the circumference of the second liquid injection hole and is connected to the first plastic part. The second annular step is connected to the side of the first annular step close to the second liquid injection hole. A through hole is provided on the first annular step, and the through hole communicates the space on the side of the diversion support structure away from the cover body or the housing with the second liquid injection hole;

[0011] Wherein, along the axial direction of the second liquid injection hole, the distance between the end face of the first annular step on the side away from the cover body or the housing and the end face of the second annular step on the side away from the cover body or the housing is a, and the value range of a is 0.3mm ≤ a ≤ 3mm.

[0012] Optionally, along the radial direction of the second liquid injection hole, the distance between the section of the through hole close to the second annular step and the outer peripheral wall of the second annular step is L;

[0013] Wherein, the relationship between L and a satisfies: 0 ≤ L / a ≤ 5;

[0014] The value range of L is: 0mm ≤ L ≤ 10mm.

[0015] Optionally, the diameter of the first liquid injection hole is φD, and the inner diameter of the second annular step is φE;

[0016] Wherein, the relationship between φD and φE satisfies: 1.1 ≤ φE / φD ≤ 2.6;

[0017] The value range of φD is: 2mm ≤ φD ≤ 5mm.

[0018] Optionally, the cover body is provided with the first liquid injection hole and a guiding flange. The guiding flange is disposed around the circumference of the first liquid injection hole and extends into the second liquid injection hole;

[0019] Along the axial direction of the second liquid injection hole, the distance between the end face of the guiding flange on the side close to the first plastic part and the end face of the first annular step on the side close to the cover body is g;

[0020] Wherein, the value range of g is 0.1mm ≤ g ≤ 3mm.

[0021] Optionally, the first annular step and the first plastic part are connected through a first transition surface, the first transition surface faces the second liquid injection hole, the guiding flange and the cover body are connected through a second transition surface, and the second transition surface faces away from the first liquid injection hole;

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

[0023] Optionally, the inner diameter of the first annular step is φm, and φm and φE satisfy: φm≥φE;

[0024] The flow area of the first injection hole is S1, and φm, φD and g satisfy:

[0025] π·φm·g≥0.8S1;

[0026]

[0027] Optionally, the battery includes a pole group, which is located on the side of the first plastic part away from the cover body, the pole group includes a pole ear and a connecting plate, the connecting plate is connected to the pole ear, the connecting plate is located on the side close to the first plastic part, and the end face of the connecting plate away from the pole group and the end face close to the first annular step intersect to form an edge; along the radial direction of the second injection hole, the spacing between the outer peripheral wall of the first annular step away from the second injection hole and the edge is b, and the value range of b is b≥0.3mm.

[0028] Optionally, along the axial direction of the second injection hole, a distance between an end surface of the pole ear close to the first plastic part and an end surface of the second annular step away from the cover body is c, and a value range of c is c≥0.1 mm.

[0029] Optionally, the through holes are provided in n numbers, and the n through holes are arranged at intervals in the circumferential direction of the first annular step, and n≥2;

[0030] The flow area of the first injection hole is S1, the flow area of the through hole is S2, and S1 and S2 satisfy: S2·n≥0.8S1.

[0031] Optionally, the distance between the cut surfaces of two adjacent through holes on the side close to each other is e, and the value range of e is e≥2 mm.

[0032] The beneficial effects of the present invention are:

[0033] The present invention provides a battery, including a cover plate body, a shell and a first plastic part. The cover plate body and the shell form a receiving cavity for mounting a pole group, a first injection hole is provided on the cover plate body or the shell, a second injection hole is provided on the first plastic part, the second injection hole is connected with the first injection hole, a flow guiding support structure includes a first annular step and a second annular step parallel to the first plastic part, the first annular step is arranged around the circumference of the second injection hole, the second annular step is connected with a side of the first annular step close to the second injection hole, a through hole is provided on the first annular step, and the through hole connects the space on the side of the flow guiding support structure away from the cover plate body or the shell with the second injection hole. When injecting liquid, electrolyte can be injected into the receiving cavity through the first injection hole, the second injection hole and / or the through hole, the flow of electrolyte is relatively smooth, and the injection efficiency is high. When evacuating, the end face of the second annular step facing the pole group can support the insulating tape to prevent the insulating tape from blocking the through hole. The gas in the accommodating cavity can be discharged out of the shell through the through hole, the second injection hole and the first injection hole. Vacuuming is easy to achieve and the vacuuming efficiency is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0035] Figure 1 This is a schematic diagram of the structure of the battery provided in the first embodiment of the present invention;

[0036] Figure 2 for Figure 1 A partial enlarged view of the middle A;

[0037] Figure 3 A bottom view of the battery provided in the first embodiment of the present invention;

[0038] Figure 4 for Figure 3 A partial enlarged view of point B in the middle;

[0039] Figure 5 A cross-sectional view of a battery provided in Embodiment 1 of the present invention;

[0040] Figure 6 for Figure 5 A partial enlarged view of point C in the middle.

[0041] In the figure:

[0042] 100. Cover body; 110. First liquid injection hole; 120. Guide flange; 1201. Second transition surface; 200. First plastic part; 210. Second liquid injection hole; 220. Flow guiding and supporting structure; 221. First annular step; 2211. Through hole; 2212. First transition surface; 222. Second annular step; 300. Pole; 400. Second plastic part; 410. Connecting block; 500. Shell; 600. Electrode group; 610. Tab; 620. Connecting piece; 621. Edge; 630. Insulating tape. Detailed implementation manners

[0043] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. The components of the embodiments of the present invention usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0044] Therefore, the detailed description of the embodiments of the present invention provided in the accompanying drawings below is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0045] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use. 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 thus cannot be construed as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive distinction and cannot be construed as indicating or implying relative importance. In the description of the present invention, unless otherwise stated, the meaning of "a plurality" is two or more.

[0046] In the description of the present invention, it should also be noted that unless otherwise clearly defined and limited, the terms "set" and "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection. 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 situations.

[0047] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0048] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0049] Embodiment 1

[0050] like Figures 1-4 As shown, this embodiment provides a battery, which includes a cover body 100, a shell 500 and a first plastic part 200. One side of the shell 500 is provided with an opening, and the cover body 100 is connected to the opening of the shell 500, and the shell 500 and the cover body 100 are jointly surrounded to form a receiving cavity for installing the electrode group 600.

[0051] The cover body 100 is provided with a first injection hole 110, the first plastic part 200 is arranged on one side of the cover body 100, the first plastic part 200 is provided with a second injection hole 210 and a flow guide support structure 220, and the second injection hole 210 is communicated with the first injection hole 110. The flow guide support structure 220 includes a first annular step 221 and a second annular step 222 which are sequentially connected and parallel to the first plastic part 200, the first annular step 221 is arranged around the circumference of the second injection hole 210 and connected to the first plastic part 200, and the second annular step 222 is connected to a side of the first annular step 221 close to the second injection hole 210. That is, the second annular step 222 and the first annular step 221 both extend in the direction close to the axis of the second injection hole 210, and the first annular step 221 is located on the side of the first plastic part 200 away from the cover body 100, and the second annular step 222 is located on the side of the first annular step 221 away from the cover body 100, and the first annular step 221 is provided with a through hole 2211, and the through hole 2211 is along the axial direction of the second injection hole 210 ( Figure 1The first annular step 221 is penetrated in the Z-axis direction shown in FIG. 1 , so that the space of the guide support structure 220 away from the cover body 100 is connected to the second liquid injection hole 210 .

[0052] Since the second annular step 222 and the first annular step 221 have a tendency to move toward the center of the second injection hole 210 and extend toward the side where the electrode group 600 is located, the flow guiding support structure 220 has a good flow guiding effect, which facilitates the rapid injection of the electrolyte. In addition, during the injection, the electrolyte can enter the accommodating cavity through the first injection hole 110 and the second injection hole 210, or through the first injection hole 110, the second injection hole 210 and the through hole 2211, so that the electrode group 600 is quickly immersed in the electrolyte, the flow of the electrolyte is relatively smooth, and the injection efficiency is relatively high.

[0053] During vacuuming, the end surface of the second annular step 222 facing the pole group 600 can support the insulating tape 630 to prevent the insulating tape 630 from blocking the through hole 2211, thereby ensuring smooth vacuuming. Even if the insulating tape 630 bulges toward the side where the flow guide support structure 220 is located and wraps the end surface of the second annular step 222 facing the pole group 600, the gas in the accommodating cavity can still be discharged from the shell 500 through the through hole 2211 on the first annular step 221, the second injection hole 210 and the first injection hole 110, so that vacuuming is easy to achieve and the vacuuming efficiency is high.

[0054] See also Figure 5 and Figure 6 , along the axial direction of the second injection hole 210 ( Figure 5 ), in this embodiment, the distance between the end surface of the first annular step 221 facing away from the cover body 100 and the end surface of the second annular step 222 facing away from the cover body 100 is a. Since the first annular step 221 and the second annular step 222 are parallel to the first plastic part 200, and the through hole 2211 is arranged on the first annular step 221, the distance between the end surface of the first annular step 221 facing away from the cover body 100 and the end surface of the second annular step 222 facing away from the cover body 100 is the dimension of the second annular step 222 along the axial direction of the second injection hole 210. In other words, the dimension of the second annular step 222 along the axial direction of the second injection hole 210 is also a.

[0055] Among them, the value range of a is 0.3 mm ≤ a ≤ 3 mm. For example, the value of a can be 0.3 mm, 0.4 mm, 0.5 mm, 1.0 mm, 2.0 mm or 3.0 mm. By controlling the value of a within the above range, the second annular step 222 can well support the insulating tape 630, avoiding the insulating tape 630 bulging to cover the through hole 2211 on the first annular step 221 during vacuum pumping, and at the same time, a relatively large flow space can be formed between the through hole 2211 and the insulating tape 630 for the electrolyte or gas to flow. Otherwise, if the value of a is too small, the second annular step 222 cannot well support the insulating tape 630, and after the insulating tape 630 bulges towards the cover plate body 100, it may adhere to the end face of the first annular step 221 facing the electrode group 600, causing the through hole 2211 to be covered and resulting in poor vacuum pumping or liquid injection. And the value of a should not be too large either, otherwise the size of the diversion support structure 220 in the axial direction of the second liquid injection hole 210 is relatively large, causing waste of space in the accommodation cavity and being unfavorable for improving the energy density of the battery.

[0056] Further, in this embodiment, there are multiple through holes 2211 on the first annular step 221, and the multiple through holes 2211 are evenly spaced in the circumferential direction of the first annular step 221, and the centers of all the through holes 2211 are located on the same circle.

[0057] As an alternative solution, the through holes 2211 in this embodiment are set as round holes, and the centers of all the through holes 2211 are located on the same circle. The diameters of all the through holes 2211 are equal, that is, the ends of all the through holes 2211 close to the second annular step 222 are tangent to the same auxiliary circle. At this time, along the radial direction of the second liquid injection hole 210 ( Figure 5 the Y-axis direction shown in the figure), the distance between the section of the through hole 2211 close to the second annular step 222 and the outer peripheral wall of the second annular step 222 is L, that is, the distance between the section at the intersection of the through hole 2211 and the auxiliary circle and the outer peripheral wall of the second annular step 222 is L. L and a satisfy: 0 ≤ L / a ≤ 5, and the value range of L is: 0 mm ≤ L ≤ 10 mm.

[0058] Exemplarily, the value of L can be 0 mm, 1 mm, 3 mm, 5 mm, 8 mm, 10 mm, etc. The value of L / a can be 0, 1, 2, 3, 4, 5, etc. By controlling the value of L / a within the above range, the second annular step 222 can well support the insulating tape 630, preventing the insulating tape 630 from completely blocking the through hole 2211 and the second liquid injection hole 210, and ensuring the smooth progress of liquid injection and vacuum pumping. If the value of L / a is greater than 5, the tangent plane at the intersection of the through hole 2211 and the auxiliary circle is far from the outer peripheral wall of the second annular step 222. When vacuum pumping, the insulating tape 630 bulges towards the side where the diversion support structure 220 is located, which may block the through hole 2211 and the second liquid injection hole 210, resulting in difficult vacuum pumping. It should be noted that the value of L and the value of L / a cannot be negative.

[0059] Of course, in other embodiments, the through hole 2211 can also be set as a square hole, a triangular hole or other polygonal holes, as long as the ends of all the through holes 2211 on the side close to the second annular step 222 are tangent to the same auxiliary circle, which will not be elaborated one by one here.

[0060] Continue to refer to Figure 4 , 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 when injecting liquid or vacuum pumping, the flow area of the first liquid injection hole 110 is large enough to meet the usage requirements of liquid injection and vacuum pumping. In addition, in this embodiment, the second annular step 222 is in a straight cylindrical shape, and the inner diameter of the second annular step 222 is equal everywhere along the axial direction of the second liquid injection hole 210. Optionally, the inner diameter of the second annular step 222 is φE, that is, the minimum inner diameter of the diversion support structure 220 is φE, and the value of φE limits the gas or electrolyte flow rate in the second liquid injection hole 210. In order to make the flow rate of the first liquid injection hole 110 match the flow rate of the second liquid injection hole 210, the following relationship is satisfied between φD and φE: 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 or 2.6, etc. That is to say, the inner diameter φE of the second annular step 222 is 1.1 times - 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. After passing through the diversion support structure 220, the liquid injection plug has a certain expansion space to ensure good sealing.

[0061] Continue to refer to Figure 6, the cover body 100 is provided with a guide flange 120, which is arranged in the circumference of the first injection hole 110 and extends into the second injection hole 210. Through the cooperation between the guide flange 120 and the guide support structure 220, the positioning between the cover body 100 and the first plastic part 200 is accurate, and the installation accuracy is high. Further, along the axial direction of the second injection hole 210, the distance between the end face of the guide flange 120 close to the first plastic part 200 and the end face of the first annular step 221 close to the cover body 100 is g, and the value range of g is 0.1mm≤g≤3mm. For example, the value of g can be 0.1mm, 0.5mm, 1.0mm, 2.0mm or 3.0mm, etc. By limiting the size of g, a clearance space is formed between the guide flange 120 and the first annular step 221. On the one hand, interference between the guide flange 120 and the first annular step 221 during assembly is avoided; on the other hand, the through hole 2211 on the first annular step 221 can be avoided, so that the gas or electrolyte can flow more smoothly in the through hole 2211, ensuring that the insulating tape 630 will not block the second liquid injection hole 210, and the liquid injection and vacuum extraction are smooth, with high assembly efficiency.

[0062] Furthermore, the first annular step 221 is connected to the first plastic part 200 through a first transition surface 2212, the first transition surface 2212 faces the second injection hole 210, and the first transition surface 2212 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 2212, 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 first annular step 221 facing the second injection hole 210, thereby avoiding the connection between the first plastic part 200 and the first annular step 221 being too sharp, which is beneficial to protecting the guide flange 120 from damage. The guide flange 120 is connected to the cover plate body 100 through a second transition surface 1201, and the second transition surface 1201 faces away from the first injection hole 110. The second transition surface 1201 is a part of the conical surface, so that the guide flange 120 can cooperate with the first transition surface 2212, and play a good guiding role when inserted into the second injection hole 210. Along the radial direction of the second injection hole 210, there is a gap h between the first transition surface 2212 and the second transition surface 1201, and the value range of h is h≥0.1mm. For example, 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 arrangement can ensure that there is sufficient assembly clearance between the cover body 100 and the first plastic part 200, avoiding interference caused by insufficient assembly clearance between the two, resulting in poor battery assembly, which may affect the sealing of subsequent batteries.

[0063] Continue to seeFigure 6 , the battery includes a pole group 600, which is disposed on the side of the first plastic part 200 away from the cover plate body 100. The pole group 600 includes pole tabs 610 and connecting pieces 620. The connecting piece 620 is connected to the pole tab 610. The connecting piece 620 is located on the side close to the first plastic part 200. One end of the connecting piece 620 is welded to the pole tab 610, and the other end of the connecting piece 620 is connected to the pole post 300 on the cover plate body 100. An insulating tape 630 is wrapped around the connecting piece 620 and the pole tab 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 tab 610 are welded, and at the same time ensure good insulation between the connecting piece 620 and the cover plate body 100, and good insulation between the pole tab 610 and the cover plate body 100.

[0064] The battery further includes a second plastic part 400 and a connecting block 410. The second plastic part 400 is disposed on the side of the cover plate body 100 away from the pole group 600. The connecting block 410 is located on the side of the second plastic part 400 away from the pole group 600 and is embedded in the accommodation groove of the second plastic part 400. The pole post 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 setting 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 post 300 and the end face of the cover plate body 100 on the side away from the pole group 600.

[0065] The end face of the connecting piece 620 on the side away from the pole group 600 and the end face close to the first annular step 221 intersect to form an edge 621; along the radial direction of the second liquid injection hole 210, the distance between the outer peripheral wall of the first annular step 221 away from the second liquid injection hole 210 and the edge 621 is b, and the value range of b is b≥0.3mm. It should be noted that b is the minimum distance between the flow guiding support structure 220 and the connecting piece 620. Exemplarily, the value of b can be 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, thereby triggering a short-circuit risk.

[0066] Further, along the axial direction of the second liquid injection hole 210, the distance between the end face of the tab 610 close to the first plastic part 200 and the end face of the second annular step 222 away from the cover plate body 100 is c, and the value range of c is c≥0.1 mm. Exemplarily, the value of c can be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, etc., which will not be listed one by one here. The above setting can ensure that there is enough assembly clearance between the second annular step 222 and the tab 610 to accommodate the insulating tape 630, avoiding interference between the two when the assembly clearance is insufficient, and the insulating tape 630 is squeezed and worn during long-term use, which may cause the insulating tape 630 to rupture, and further cause a short-circuit risk.

[0067] Continue to refer to Figure 4 and Figure 5 In this embodiment, the first annular step 221 is in a straight cylinder shape, and along the axial direction of the second liquid injection hole 210, the inner diameter of the first annular step 221 is equal everywhere. Optionally, the inner diameter of the first annular step 221 is φm, and φm and φE satisfy: φm≥φE.

[0068] The flow area of the first liquid injection hole 110 is S1, and φm, φD and g satisfy:

[0069] π·φm·g≥0.8S1;

[0070]

[0071] Among them, in the circumferential direction of the flow guiding and supporting structure 220, the flowable area between the guiding flange 120 and the first annular step 221 is π·φm·g. Through the above size limitation, it can be ensured that the flowable area between the guiding flange 120 and the first annular step 221 matches the flow area of the first liquid injection hole 110, ensuring that the electrolyte or gas can quickly pass through the flow space between the guiding flange 120 and the first annular step 221, and there will be no situation of electrolyte overflow, which is beneficial to improving the liquid injection efficiency and the vacuum pumping efficiency.

[0072] Further, in this embodiment, there are n through holes 2211, and the n through holes 2211 are arranged at intervals in the circumferential direction of the first annular step 221, n≥2, the through holes 2211 are all round holes, and the diameter of each through hole 2211 is φF, and the value range of φF is φF≥0.3 mm. For example, the value of φF can be 0.3 mm, 0.5 mm, 0.8 mm, 1.0 or 1.2 mm, etc. The flow area of the first liquid injection hole 110 is S1, and the flow area of the through holes 2211 is S2, and S1 and S2 satisfy:

[0073] S2·n≥0.8S1;

[0074]

[0075] Among them, in the axial direction of the second liquid injection hole 210, the total flow-through area of all the through holes 2211 on the first annular step 221 is S2·n. Through the above-mentioned dimensional limitations, it can be ensured that the flow-through area between the guiding flange 120 and the first annular step 221 matches the sum of the flow-through areas of all the through holes 2211, ensuring that the electrolyte or gas can quickly pass through the through holes 2211 on the first annular step 221 without the occurrence of electrolyte overflow, which is beneficial to improving the liquid injection efficiency and the vacuum pumping efficiency.

[0076] In this embodiment, n = 8 is taken as an example for illustration. At this time, the relationship between S1 and S2 satisfies: S2≥0.1S1. Of course, in other embodiments, the number of the through holes 2211 can also be set to 2, 3, 4, 5, 6, etc., which will not be elaborated here one by one.

[0077] Of course, in some alternative embodiments, when the through holes 2211 are square holes, triangular holes or other polygonal holes, it is also necessary to ensure that S2·n≥0.8S1. At this time, the calculation formula of S2 is different, and its cross-sectional area can be calculated according to the shape of the through holes 2211, which will not be elaborated here one by one.

[0078] Continue to refer to Figure 4 , in this embodiment, the distance between the cut surfaces on the side where two adjacent through holes 2211 are close to each other is e, and the value range of e is e≥2mm. For example, the value of e can be 2mm, 3mm, 4mm, 5mm, etc. By limiting the value of e within the above range, it is ensured that the mechanical strength of the first annular step 221 after the through holes 2211 are opened is still relatively high, and problems such as deformation or fracture are not likely to occur. Otherwise, when the value of e is too small, the distance between two adjacent through holes 2211 is too close, the mechanical strength of the first annular step 221 is insufficient, and deformation or cracking is likely to occur, reducing the reliability of the battery. Of course, the value of e should not be too large either, otherwise the distance between two adjacent through holes 2211 is too large, the arrangement quantity of the through holes 2211 is reduced, the flow-through area of the electrolyte or gas at the through holes 2211 is reduced, and there may be a risk of liquid overflow during liquid injection and vacuum pumping.

[0079] Next, the above-mentioned dimensional limitations are verified with batteries in some specific embodiments. Samples of different size parameters are made for the first plastic part 200 and the flow guiding and supporting structure 220 in the battery. Then, each cover body 100 and the housing 500 are assembled to form a battery, and tests of liquid injection and vacuum pumping are carried out on each battery, and the results are shown in Table 1.

[0080] Table 1

[0081]

[0082] As can be seen from the above results, in Example 1, the value of parameter a is close to the lower limit of its dimensional limit, and the remaining parameters are all taken as normal values, slightly higher than the lower limit of their corresponding dimensional limits. At this time, the insulating tape 630 does not block the through hole 2211 and the second liquid injection hole 210, and the liquid injection and vacuum pumping are both relatively smooth, and there is no situation of electrolyte overflow.

[0083] In Example 2, the value of parameter φF is close to the lower limit of its dimensional limit, and the remaining parameters are all taken as normal values, slightly higher than the lower limit of their corresponding dimensional limits. At this time, the insulating tape 630 does not block the through hole 2211 and the second liquid injection hole 210, and the liquid injection and vacuum pumping are both relatively smooth.

[0084] In Example 3, the value of parameter L / a is close to the upper limit of its dimensional limit, and the remaining parameters are all taken as normal values, slightly higher than the lower limit of their corresponding dimensional limits. At this time, the insulating tape 630 does not block the through hole 2211 and the second liquid injection hole 210, and the liquid injection and vacuum pumping are both relatively smooth, and there is no situation of electrolyte overflow.

[0085] In Example 4, the value of parameter π·φm·g is relatively close to the value of 0.8S1, the value of π·φm·g is slightly greater than 0.8S1, and the remaining parameters are all taken as normal values, slightly higher than the lower limit of their corresponding dimensional limits. At this time, the insulating tape 630 does not block the through hole 2211 and the second liquid injection hole 210, and the liquid injection and vacuum pumping are both relatively smooth, and there is no situation of electrolyte overflow.

[0086] In Example 5, the value of parameter S2·n is relatively close to the value of 0.8S1, the value of S2·n is slightly greater than 0.8S1, and the remaining parameters are all taken as normal values, slightly higher than the lower limit of their corresponding dimensional limits. At this time, the insulating tape 630 does not block the through hole 2211 and the second liquid injection hole 210, and the liquid injection and vacuum pumping are both relatively smooth, and there is no situation of electrolyte overflow.

[0087] In Example 6, all parameters are taken as normal values, slightly higher than the lower limit of their corresponding dimensional limits. At this time, the insulating tape 630 does not block the through hole 2211 and the second liquid injection hole 210, and the liquid injection and vacuum pumping are both relatively smooth, and there is no situation of electrolyte overflow.

[0088] Referring to Comparative Example 1, the value of parameter a exceeds the lower limit of 0.3mm ≤ a ≤ 3mm, and the remaining parameters are all taken as normal values. At this time, when the production line performs a vacuum pumping operation, the insulating tape 630 significantly blocks the through hole 2211 and the second liquid injection hole 210, making it difficult to pump vacuum, resulting in production delay and reduced assembly efficiency.

[0089] Referring to Comparative Example 2, the value of the parameter φF exceeds the lower limit of φF≥0.3 mm, and the remaining parameters are taken as normal values. At this time, the diameter of the through hole 2211 is small, the liquid injection speed of the second liquid injection hole 210 is reduced, it is difficult to inject liquid, the production is delayed, and the assembly efficiency is reduced.

[0090] Referring to Comparative Example 3, the value of the parameter L / a exceeds the upper limit of 0≤L / a≤5, and the remaining parameters are taken as normal values. At this time, when the production line performs a vacuum pumping operation, the insulating tape 630 significantly blocks the through hole 2211 and the second liquid injection hole 210, it is difficult to pump vacuum, the production is delayed, and the assembly efficiency is reduced.

[0091] Referring to Comparative Example 4, the value of the parameter π·φm·g is less than the value of 0.8S1. At this time, the flowable area formed between the first annular step 221 and the guiding flange 120 of the cover body 100 is small, there is a liquid overflow phenomenon during liquid injection, the liquid injection is not smooth, affecting the production rhythm, and the assembly efficiency is reduced.

[0092] Referring to Comparative Example 5, the value of the parameter S2·n is less than the value of 0.8S1. At this time, the diameter of the through hole 2211 on the first annular step 221 is small, the flowable area of all the through holes 2211 is small, there is a liquid overflow phenomenon during liquid injection, the liquid injection is not smooth, affecting the production rhythm, and the assembly efficiency is reduced.

[0093] In summary, it can be known that when the above parameters φD, φF, m, g, a, L / a, 0.8S1, π·φm·g, S2·n all meet their corresponding dimensional limits, it can be ensured that the insulating tape 630 does not block the through hole 2211 and the second liquid injection hole 210, and the flowable area between the cover body 100 and the first plastic part 200 is sufficient, the flowable area of all the through holes 2211 is sufficient, the liquid injection and vacuum pumping are smooth, and the assembly efficiency is high.

[0094] Example Two

[0095] The present embodiment provides a battery, which is different from the battery in the first embodiment in that: in the present embodiment, the first injection hole 110 is arranged 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 sandwiched between the housing 500 and the electrode group 600, and the second injection hole 210 on the first plastic part 200 is connected with the first injection hole 110 on the housing 500. The structures of the first plastic part 200 and the guide support structure 220 are the same as those in the first embodiment, the guide support structure 220 is arranged around the circumference of the second injection hole 210, and the guide support structure 220 is located on the side of the first plastic part 200 away from the housing 500, and the space on the side of the guide support structure 220 away from the housing 500 can be connected with the second injection hole 210 through the through hole 2211 on the guide support structure 220. The first annular step 221 of the diversion support structure 220 is connected to the first plastic part 200, and the second annular step 222 and the first annular step 221 both extend toward the center of the second injection hole 210, and the first annular step 221 is located on the side of the first plastic part 200 away from the shell 500, and the second annular step 222 is located on the side of the first annular step 221 away from the shell 500, and the through hole 2211 passes through the first annular step 221.

[0096] Further, along the axial direction of the second injection hole 210, the distance between the end surface of the first annular step 221 facing away from the housing 500 and the end surface of the second annular step 222 facing away from the housing 500 is a. The value range of a is also 0.3mm≤a≤3mm. Exemplarily, the value of a can be 0.3mm, 0.4mm, 0.5mm, 1.0mm, 2.0mm or 3.0mm, etc.

[0097] By adopting the above-mentioned first plastic part 200 and guide support structure 220, the second annular step 222 can well support the insulating tape 630, so as to prevent the insulating tape 630 from bulging and covering the through hole 2211 on the first annular step 221 during vacuuming. At the same time, a larger flow space can be formed between the through hole 2211 and the insulating tape 630 to allow electrolyte or gas to flow, thereby ensuring smooth battery filling or vacuuming, and high filling and vacuuming efficiency.

[0098] The remaining structures in this embodiment are the same as those in the first embodiment and will not be described in detail here.

[0099] Obviously, the above-mentioned embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

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, and a second liquid injection hole is provided on the first plastic part, and the second liquid injection hole is connected with the first liquid injection hole; A flow guiding support structure, comprising a first annular step and a second annular step parallel to the first plastic part, wherein the first annular step is arranged around the circumference of the second liquid injection hole and connected to the first plastic part, and the second annular step is connected to a side of the first annular step close to the second liquid injection hole, and a through hole is provided on the first annular step, wherein the through hole connects a space of the flow guiding support structure away from the cover plate body or the shell with the second liquid injection hole; Among them, along the axial direction of the second injection hole, the distance between the end surface of the first annular step away from the cover body or the shell side and the end surface of the second annular step away from the cover body or the shell side is a, and the value range of a is 0.3mm≤a≤3mm.

2. The battery according to claim 1, characterized in that, Along the radial direction of the second liquid injection hole, the distance between the section of the through hole close to the second annular step and the outer peripheral wall of the second annular step is L; Among them, L and a satisfy: 0≤L / a≤5; The value range of L is: 0mm≤L≤10mm.

3. The battery according to claim 1, characterized in that, The diameter of the first injection hole is φD, and the inner diameter of the second annular step is φE; Among them, φD and φE satisfy: 1.1≤φE / φD≤2.6; The value range of φD is: 2mm≤φD≤5mm.

4. The battery according to claim 1, wherein The cover plate body is provided with the first liquid injection hole and a guide flange, wherein the guide flange is arranged in the circumference of the first liquid injection hole and extends into the second liquid injection hole; Along the axial direction of the second injection hole, the distance between the end surface of the guide flange close to the first plastic part and the end surface of the first annular step close to the cover body is g; Among them, the value range of g is 0.1mm≤g≤3mm.

5. The battery according to claim 4, wherein The first annular step is connected to the first plastic part via a first transition surface, the first transition surface faces the second injection hole, 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 h between the first transition surface and the second transition surface, and the value range of h is h≥0.1 mm.

6. The battery according to claim 4, characterized in that, The inner diameter of the first annular step is φm, and φm and φE satisfy: φm≥φE; The flow area of the first injection hole is S1, and φm, φD and g satisfy: π·φm·g≥0.8S1; 7. The battery according to claim 4, wherein, The battery comprises an electrode group, the electrode group is located on a side of the first plastic part away from the cover plate body, the electrode group comprises 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 on a side away from the electrode group and an end surface close to the first annular step intersect to form an edge; Along the radial direction of the second liquid injection hole, the spacing between the outer peripheral wall of the first annular step away from the second liquid injection hole and the edge is b, and the value range of b is b≥0.3 mm.

8. The battery according to claim 7, characterized in that, Along the axial direction of the second injection hole, the distance between the end surface of the pole ear close to the first plastic part and the end surface of the second annular step away from the cover body is c, and the value range of c is c≥0.1mm.

9. The battery according to claim 1, characterized in that, The through holes are provided in n numbers, and the n through holes are arranged at intervals in the circumferential direction of the first annular step, and n≥2; The flow area of the first injection hole is S1, the flow area of the through hole is S2, and S1 and S2 satisfy: S2·n≥0.8S1.

10. The battery according to claim 9, wherein The distance between the cut surfaces of two adjacent through holes on the side close to each other is e, and the value range of e is e≥2mm.

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