Positive electrode confluence plate and positive electrode assembly
By designing a positive electrode bus disk with a convex ring and a cutting groove, the problem of low infiltration efficiency of large cylindrical lithium batteries is solved, and better distribution of electrolyte and improved battery performance are achieved.
Patent Information
- Application Number
- CN202421434261.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-21
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-06-21
AI Technical Summary
During the injection process of existing large cylindrical lithium batteries, the electrolyte infiltration efficiency is low, affecting battery performance.
A positive electrode bus disk is designed, which comprises a circular substrate with a central hole arranged concentrically and a convex ring for welding with the pole column. There are penetrating liquid permeability holes on the top surface of the convex ring, and cutting grooves are arranged in the circumferential direction on the substrate to form an electrolyte collection area and an underwater path.
Through this design, the electrolyte can be directly dispersed to the end of the core, improving the infiltration efficiency, enhancing the uniform distribution of the electrolyte and battery performance.
Smart Images
Figure CN222953319U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of lithium batteries, in particular to a positive electrode busbar and a positive electrode assembly. Background Art
[0002] At present, with the rapid development of the new energy industry, society's requirements for the energy density, safety performance, and fast charging performance of lithium-ion batteries have been further improved. As a highly recognized solution, large cylindrical batteries have ushered in a broad market space. Large cylindrical batteries usually use two upper and lower busbars to connect the positive and negative electrodes to the core. In order to reliably connect the busbars to the positive and negative electrodes, the busbars need to be pressed tightly against the core and laser welded. Usually, the injection holes of cylindrical batteries are concentrically arranged on the poles or shells, and most of the added electrolyte will flow directly into the center hole of the core, and penetrate from the center hole between the pole piece and the diaphragm to the entire core, greatly affecting the electrolyte infiltration efficiency. Utility Model Content
[0003] In view of the above-mentioned deficiencies of the prior art, the technical problem to be solved by the present invention is: how to provide a positive electrode busbar and a positive electrode assembly with a reasonable design that can allow the electrolyte to be directly dispersed to the end of the winding core, thereby facilitating the infiltration of the electrolyte.
[0004] In order to solve the above technical problems, the utility model adopts the following technical solutions:
[0005] A positive busbar, characterized in that it includes a circular substrate, the substrate having a concentrically arranged center hole and a convex ring for welding to a pole, the convex ring being formed by an overall depression on one side of the substrate and protruding toward the other side; the top surface of the convex ring having a liquid-permeable hole extending therethrough; the substrate having cutting grooves uniformly distributed along the circumferential direction, the cutting grooves passing through the substrate, one end of which is connected to the center hole, and the other end extending toward the outside of the substrate, a welding area being provided between two adjacent cutting grooves.
[0006] In the above structure, since the convex ring is formed by the overall depression of the substrate, the depressed portion can form an electrolyte distribution area between the busbar and the core. After the electrolyte is injected from the liquid permeable hole, it will first flow into this area. A part of it will directly seep from this area to between the electrode and the diaphragm, and the other part will extend radially along the cutting groove toward the core and seep from the gap between the core layers exposed at the cutting groove, so that the electrolyte can be dispersed and seep into each layer of the core, thereby improving the efficiency of infiltration.
[0007] Furthermore, the top of the convex ring has a flow groove formed by a depression, the flow groove extends in a ring shape along the circumference of the convex ring, and the liquid permeable hole is located at the bottom of the flow groove.
[0008] Since the convex ring needs to be welded to the pole, the electrolyte needs to be injected from the injection hole on the pole. By setting the flow slot in a ring shape, the injected electrolyte can be better received and flow into the liquid permeable hole through the flow slot.
[0009] Furthermore, a plurality of liquid-permeable holes are evenly distributed along the circumference of the convex ring.
[0010] In this way, the electrolyte can be evenly injected into the core through the evenly distributed liquid permeable holes, so that the electrolyte can be better distributed and infiltrated.
[0011] Furthermore, the liquid-permeable hole extends into an arc shape along the circumference of the convex ring.
[0012] Furthermore, the welding area is located on a side of the substrate facing the convex ring and is in the shape of a strip groove, so that the thickness of the welding area is smaller than the thickness of the substrate.
[0013] In this way, the welding area can be determined by the shape of the groove, and the thickness of the welding area can be used to achieve better penetration welding.
[0014] Furthermore, one end of the welding zone is close to the convex ring, and the other end extends outward along the spiral line; the cutting groove and the welding zone are arranged in a spiral shape in the same direction.
[0015] In this way, the length of the welding zone and the cutting groove can be increased, thereby increasing the welding area and the electrolyte lowering area.
[0016] A positive electrode assembly, characterized in that it includes the positive electrode busbar and pole as described above, the outer side of the pole having a concentrically arranged first annular groove, the bottom of the first annular groove having a through-arranged injection hole, and a plurality of the injection holes are evenly distributed along the circumferential direction; the inscribed circle diameter of the plurality of injection holes is larger than the inscribed circle diameter of the plurality of liquid-permeable holes, and the circumscribed circle diameter of the plurality of injection holes is smaller than the circumscribed circle diameter of the plurality of liquid-permeable holes.
[0017] In this way, the convex ring of the busbar is welded concentrically with the pole, the injection hole and the liquid permeable hole are connected, and the electrolyte can be added.
[0018] Furthermore, the inner side of the pole has a concentrically arranged second annular groove, and the second annular groove is arranged opposite to the first annular groove in the axial direction; the height of the convex ring is greater than the depth of the second annular groove, and the width is smaller than the width of the second annular groove, and it is fitted in the second annular groove.
[0019] Furthermore, one side of the injection hole facing outward is expanded outward along the edge to form a relatively thin step at the bottom of the injection hole, and the step is connected to the convex ring fitted in the second annular groove by penetration welding.
[0020] Furthermore, the injection hole extends into an arc shape along the circumference of the first annular groove.
[0021] In summary, the utility model has the advantages of reasonable design, enabling the electrolyte to be directly dispersed to the end of the winding core, which is beneficial to the infiltration of the electrolyte. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 Schematic diagram of the cross-sectional structure of a large cylindrical battery.
[0023] Figure 2 Schematic diagram of the internal structure of a large cylindrical battery.
[0024] Figure 3 Schematic diagram of the structure of the guide tube.
[0025] Figure 4 It is a schematic diagram of the structure of the inner shell.
[0026] Figure 5 Schematic diagram of the cross-sectional structure of the positive busbar.
[0027] Figure 6 It is a schematic diagram of the structure of the positive busbar.
[0028] Figure 7 Schematic diagram of the cross-sectional structure of the pole.
[0029] Figure 8 and Fig. 9 They are schematic diagrams of the structures at the top and bottom of the pole respectively.
[0030] Fig.10 It is a schematic diagram of the structure of the cover plate. DETAILED DESCRIPTION
[0031] The utility model is further described in detail below in conjunction with a large cylindrical battery using the structure of the utility model.
[0032] When implementing: Figures 1 to 10As shown, a large cylindrical battery with rapid heat dissipation capability comprises an outer shell 1 and an inner shell 2 arranged concentrically, wherein the outer shell 1 is provided with a positive busbar 3, a winding core assembly 4 and a negative busbar 5 in sequence; one end of the inner shell 2 is connected to the outer shell 1 through an insulated pole 6, and the other end is welded to the shell 1 through a cover plate 7. Specifically, the outer diameter of the cover plate 7 matches the diameter of the shell 1 and is welded to the shell 1 circumferentially, the middle part of the cover plate 7 has a through hole consistent with the diameter of the inner shell 2, the inner shell 2 passes through the through hole and is welded to the cover plate 7 circumferentially, the cover plate 7 has a convex ridge formed by inward concavity, the convex ridge abuts against the negative busbar 5, and the side of the negative busbar 5 is welded to the outer shell 1 circumferentially. The middle part of the inner shell 2 has an inner hole set through, and is penetrated by a liquid cooling pipe 8, the surface of the liquid cooling pipe 8 is coated with an insulating material and is attached to the inner wall of the inner shell 2.
[0033] The winding core assembly 4 includes a guide tube 41 made of insulating material and a winding core 42 wound on the guide tube 41, and both ends of the guide tube 41 are protruding; the middle of the positive busbar 3 and the negative busbar 5 have a concentrically arranged center hole, the diameter of the center hole matches the outer diameter of the guide tube 41, and is coaxially sleeved on the guide tube 41. Figure 3 As shown, the outer circumferential surface of the guide tube 41 is provided with a guide groove 43 which is axially penetrating, and a plurality of guide grooves 43 are evenly distributed along the circumferential direction. In this way, the winding core is wound on the guide tube, and the two ends of the guide tube are protruding, so that the positive busbar and the negative busbar can be better positioned, which is convenient for welding and assembly. At the same time, the guide tube forms a conducting space between the guide groove and the winding core, the positive busbar and the negative busbar, so that the electrolyte injected from one end can flow quickly to the other end through the guide groove, which is beneficial to improve the assembly efficiency of the battery.
[0034] One end of the outer shell 1 has an integrally formed end plate, and the middle of the end plate has a concentrically arranged assembly hole; Figure 4 As shown, the inner shell 2 is tubular as a whole, and a concentrically arranged connection disk is formed in a radially outwardly protruding end toward the assembly hole; the pole 6 is annular, and the outer ring of the pole 6 is insulated and riveted to the assembly hole of the end plate through a first insulating ring 11, and the inner ring is insulated and riveted to the connection disk through a second insulating ring 21. The inner side of the end plate has a ring-shaped insulating pad 12, the inner ring of the insulating pad 12 is concentrically connected to the first insulating ring 11, and is riveted between the pole 6 and the end plate; the outer ring of the insulating pad 12 has an annular boss protruding toward the positive busbar 3, and the annular boss abuts against the positive busbar 3.
[0035] like Figure 7 to Figure 9 As shown, the outer side of the pole 6 has a concentrically arranged first annular groove 61, and the bottom of the first annular groove 61 has a through-arranged injection hole 62, and a plurality of the injection holes 62 are evenly distributed along the circumference. In this embodiment, three injection holes are evenly distributed along the circumference, and the injection holes 62 extend into an arc along the circumference of the first annular groove 61; the first annular groove 61 is equipped with a sealing ring 9 for welding sealing, and the thickness of the sealing ring 9 matches the depth of the first annular groove 61.
[0036] In this embodiment, the inner side of the pole 6 has a concentrically arranged second annular groove 63, and the second annular groove 63 is arranged opposite to the first annular groove 61 in the axial direction; Figure 5 and Figure 6 As shown, the positive busbar 3 includes a circular substrate 31, and the substrate 31 has a protruding ring 32 that is integrally recessed and protrudes toward one side, and the protruding ring 32 is arranged concentrically with the substrate 31; the height of the protruding ring 32 is greater than the depth of the second annular groove 63, and the width is smaller than the width of the second annular groove 63, and the protruding ring 32 is fitted in the second annular groove 63, and the protruding ring 32 is welded to the second annular groove 63. In this embodiment, the side of the injection hole 62 facing outward is expanded outward along the edge to form a relatively thin step at the bottom of the injection hole 62, and the step is connected to the protruding ring 32 fitted in the second annular groove 63 by penetration welding.
[0037] The convex ring 32 has a through-hole 33, and a plurality of the liquid-permeable holes 33 are evenly distributed along the circumference of the convex ring 32. In this embodiment, in order to allow the electrolyte to flow into the winding core more evenly through the liquid-permeable holes 33, the liquid-permeable holes 33 extend into an arc along the circumference of the convex ring 32, and 6 liquid-permeable holes 33 are evenly distributed along the circumference.
[0038] Specifically, the convex ring 32 is provided with a concave flow groove 34, the flow groove 34 extends in a ring shape along the circumference of the convex ring 32, and the liquid permeable hole 33 is located at the bottom of the flow groove 34. In this way, the electrolyte flowing in from the injection hole of the first annular groove 61 will first enter the flow groove 34, and then flow from the flow groove 34 into the battery cell through the nearest liquid permeable hole 33.
[0039] like Figure 6As shown, the substrate 31 has a concentrically arranged center hole 35 and a circumferentially evenly arranged cutting grooves 36, the cutting grooves 36 penetrate the substrate 31, and one end is connected to the center hole 35, and the other end extends toward the outside of the substrate 31, and there is a welding area 37 between two adjacent cutting grooves 36. In this way, the cutting grooves evenly arranged in the circumference make the overall flexibility of the substrate better, so that it can better fit the pole ear welding and ensure the welding quality. At the same time, because the cutting grooves extend toward the outside of the substrate, the radial layers of the winding core can be exposed at the cutting grooves, so as to facilitate the electrolyte to flow into the layers of the winding core through the cutting grooves.
[0040] In this embodiment, the welding area 37 is located on the side of the substrate 31 away from the winding core and is in the shape of a strip groove, so that the thickness of the welding area 37 is less than the thickness of the substrate 31. In this way, the welding area can be determined by the shape of the groove, and the thickness of the welding area 37 can be used to achieve better penetration welding.
[0041] In addition, one end of the welding area 37 is close to the convex ring 32, and the other end extends outward along the spiral line; the cutting groove 36 and the welding area 37 are arranged in a spiral line in the same direction. In this way, the length of the welding area and the cutting groove can be increased, thereby increasing the welding area and the electrolyte drop area.
[0042] In this embodiment, by inserting a liquid cooling tube through the inner hole of the inner shell, and making the liquid cooling tube and the inner shell insulated and close to each other, the heat at the center of the cylindrical battery can be taken away by the coolant flowing through the liquid cooling tube, thereby cooling the center of the battery, thereby reducing the temperature difference of the battery, which is conducive to improving the uniformity of the battery temperature and making the battery work more stable. Moreover, the inner shell of this structure can form a support in the middle of the winding core, thereby preventing the internal collapse of the winding core and ensuring the full performance of the battery.
[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A positive busbar, characterized in that: The invention comprises a circular substrate (31), wherein the substrate (31) has a concentrically arranged center hole (35) and a convex ring (32) for being welded to a pole, wherein the convex ring (32) is formed by an integral depression on one side of the substrate (31) and protruding toward the other side; the top surface of the convex ring (32) has a liquid-permeable hole (33) extending therethrough; and the substrate (31) has cutting grooves (36) uniformly arranged along the circumferential direction, wherein the cutting grooves (36) penetrate the substrate (31), one end of the cutting grooves is connected to the center hole (35), and the other end is extended toward the outside of the substrate (31), and a welding area (37) is provided between two adjacent cutting grooves (36).
2. The positive busbar according to claim 1, characterized in that: The top of the convex ring (32) has a concave flow groove (34), the flow groove (34) extends in a ring shape along the circumference of the convex ring (32), and the liquid permeable hole (33) is located at the bottom of the flow groove (34).
3. The positive busbar according to claim 2, characterized in that: A plurality of liquid-permeable holes (33) are evenly distributed along the circumference of the convex ring (32).
4. The positive busbar according to claim 1, characterized in that: The liquid permeable hole (33) extends in an arc shape along the circumference of the convex ring (32).
5. The positive busbar according to claim 1, characterized in that: The welding area (37) is located on a side of the base plate (31) facing the convex ring (32) and is in the shape of a strip groove, so that the thickness of the welding area (37) is smaller than the thickness of the base plate (31).
6. The positive busbar according to claim 5, characterized in that: One end of the welding area (37) is close to the convex ring (32), and the other end extends outward along a spiral line; the cutting groove (36) and the welding area (37) are arranged in a spiral line in the same direction.
7. A positive electrode assembly, characterized in that: It comprises a positive busbar and a pole (6) as claimed in any one of claims 1 to 6, wherein the outer side of the pole (6) has a first annular groove (61) arranged concentrically, and the bottom of the first annular groove (61) has a liquid injection hole (62) arranged through, and a plurality of the liquid injection holes (62) are evenly distributed along the circumferential direction; the diameter of the inscribed circle of the plurality of the liquid injection holes (62) is greater than the diameter of the inscribed circle of the plurality of the liquid permeable holes (33), and the diameter of the circumscribed circle of the plurality of the liquid injection holes (62) is smaller than the diameter of the circumscribed circle of the plurality of the liquid permeable holes (33).
8. The positive electrode assembly according to claim 7, characterized in that The inner side of the pole (6) has a concentrically arranged second annular groove (63), the second annular groove (63) and the first annular groove (61) being arranged opposite to each other in the axial direction; the convex ring (32) has a height greater than a depth of the second annular groove (63) and a width less than a width of the second annular groove (63), and is fitted in the second annular groove (63).
9. The positive electrode assembly according to claim 8, characterized in that The outward side of the injection hole (62) is expanded outward along the edge to form a step that thins the bottom of the injection hole (62), and the step is connected to the convex ring (32) fitted in the second annular groove (63) by penetration welding.
10. The positive electrode assembly according to claim 8, characterized in that The liquid injection hole (62) extends in an arc shape along the circumference of the first annular groove (61).