Power type cylindrical battery positive electrode assembly and cylindrical battery

Abstract

The positive pole assembly comprises a shell with one end open, the other end of the shell is provided with an annular end plate formed by extending inwards in the radial direction, and the middle of the annular end plate is provided with a polar plate arranged concentrically. The polar plate is hermetically connected to the annular end plate in an insulating manner; the inner side of the polar plate is provided with a confluence plate, the middle part of the confluence plate is provided with a welding boss which is formed by integrally drawing towards the polar plate, the diameter of the welding boss is matched with that of the polar plate, and the welding boss is welded on the polar plate in an attaching manner. The positive electrode assembly of the power type cylindrical battery and the cylindrical battery have the advantages of being reasonable in structural design, capable of increasing the over-current area between the confluence plate and the pole column, beneficial to reducing the internal resistance of the battery, improving the performance of the battery and the like.

Description

TECHNICAL FIELD

[0001] The utility model relates to lithium battery technical field, especially a kind of power type cylindrical battery positive pole assembly and cylindrical battery. BACKGROUND

[0002] At present, with the rapid development of new energy industry, the energy density, safety performance, fast charging performance and other requirements of lithium ion battery are further improved, and large cylindrical battery, as a widely recognized solution, welcomes broad market space.

[0003] The existing cylindrical battery has two welding methods between the pole and the bus bar, one is to use a conductive handle to connect by welding, but the cross-sectional area of the conductive handle is small, which causes the internal resistance of the battery to be large, and if the battery is charged and discharged with large current, the temperature of the conductive handle part is easy to rise, which affects the performance of the battery consistency, and there is a risk of failure. The other is to weld the edge of the liquid injection hole of the pole to the protruding part of the bus bar, since the diameter of the pole itself is small, the diameter of the liquid injection hole is smaller, and the circumference of the liquid injection hole is smaller, which determines that the welding area between the pole and the bus bar is also small, which will also increase the internal resistance of the battery, and the temperature of the welding part is easy to rise, which has a risk of failure. SUMMARY

[0004] In view of the above technical problems of the prior art, the utility model solves the technical problems of how to provide a power type cylindrical battery positive pole assembly and cylindrical battery with reasonable structure design, which can increase the flow area between the bus bar and the pole, reduce the internal resistance of the battery and improve the performance of the battery.

[0005] In order to solve the above technical problems, the utility model adopts the following technical scheme:

[0006] A power type cylindrical battery positive pole assembly, comprising a shell with one end open, the other end of the shell has an annular end plate formed by extending radially inward, the middle part of the annular end plate has a pole plate arranged concentrically, the pole plate is sealingly connected to the annular end plate; the inner side of the pole plate is provided with a bus bar, the middle part of the bus bar has a welding boss formed by drawing towards the pole plate as a whole, the diameter of the welding boss matches the pole plate, and the welding boss is welded on the pole plate.

[0007] In the above structure, the welding boss is welded with the pole plate, which can increase the welding area between the pole plate and the bus bar, and the welding boss is formed by drawing, and the edge between the welding boss and the bus bar body also has a large flow area, which can reduce the internal resistance and temperature rising speed, reduce the risk of battery failure and improve the performance of the battery.

[0008] Further, the diameter of the pole plate is 1.5-2 times the diameter of the battery core center hole.

[0009] In this way, the welding area between the busbar and the core tab can be increased while ensuring the welding area between the busbar and the core tab.

[0010] Furthermore, an annular rivet is provided between the electrode plate and the annular end plate. The cross-section of the rivet is in the shape of an "I" and it is riveted to the electrode plate and the annular end plate respectively. An insulating pad is provided between the rivet and the annular end plate.

[0011] Furthermore, the first insulating element includes a first insulating pad disposed on the inner side of the annular end plate, and a first flange protruding from the middle of the first insulating pad and engaging with the inner hole of the annular end plate; the outer side of the annular end plate has a first insulating ring in the shape of an annulus, and the inner side of the first insulating ring is connected to the first flange.

[0012] Furthermore, the outer diameter of the first insulating pad matches the inner diameter of the housing.

[0013] In this way, the first insulating pad can form an insulation barrier between the busbar and the housing, preventing short circuits.

[0014] Furthermore, a second insulating element is provided between the rivet and the electrode plate in the insulating pad.

[0015] Furthermore, the second insulating member includes a second insulating pad disposed on the inner side of the electrode plate, the outer edge of the second insulating pad being provided with a second flange that mates with the edge of the electrode plate, and the outer side of the electrode plate having an annular second insulating ring, the outer diameter of the second insulating ring being consistent with the outer diameter of the second insulating pad and being connected to the second flange.

[0016] Furthermore, the outer diameter of the first insulating ring matches the outer diameter of the rivet piece and has an outwardly protruding flange; the inner diameter of the second insulating ring matches the inner diameter of the rivet piece and has an outwardly protruding inner flange, the heights of the outer flange and the inner flange both matching the protrusion height of the rivet piece.

[0017] Furthermore, the first insulating ring and the second insulating ring are made of PPS plastic; the first insulating pad and the second insulating pad are made of fluororubber.

[0018] A cylindrical battery includes a power-type cylindrical battery positive electrode assembly as described above.

[0019] In summary, the power-type cylindrical battery positive electrode assembly and cylindrical battery of this utility model have advantages such as reasonable structural design, which can increase the flow area between the busbar and the terminal post, which is conducive to reducing the internal resistance of the battery and improving the battery performance. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is the whole structure schematic view of the embodiment of the utility model.

[0021] Figure 2 It is Figure 1 The sectional structure schematic view.

[0022] Figure 3 It is Figure 2 The local enlarged structure schematic view.

[0023] Figure 4 It is the structure schematic view of positive busbar. DETAILED DESCRIPTION

[0024] The utility model will be further explained in detail in combination with examples.

[0025] Specific implementation time: as Figures 1-4 The cylindrical battery shown in the drawing, including the shell 1 of one end open, the shell 1 in the open direction towards is sequentially provided with positive busbar, roll core, negative busbar and cover plate;The other end of the shell 1 has the annular end plate 11 formed along the radial direction inwardly, the middle part of the annular end plate 11 has the polar plate 2 concentrically arranged, the polar plate 2 is sealingly connected on the annular end plate 11 in an insulating manner;The inner side of the polar plate 2 is provided with the positive busbar 3, the positive busbar 3 includes the busbar body 31 that is overall circular, the middle part of the busbar body 31 has the welding boss 32 that is integrally drawn towards the polar plate 2, the diameter of the welding boss 31 matches the diameter of the polar plate 2 and is welded on the polar plate 2 in a fit manner.

[0026] The side wall of the welding boss 32 has the flow hole 33 that is provided along the radial direction, and a plurality of flow holes are arranged along the circumferential direction of the welding boss 32.Simultaneously, the busbar body 31 has the flow groove 34 that is provided through, and the flow groove 34 is arranged along the radial direction of the busbar body 31.One end of the flow groove 34 extends to the welding boss 32 and is connected with one of the flow holes 33, and the other end has the weakening groove 35 that is formed along the circumferential direction and extends to both sides.Thus, the busbar body is divided into multiple regions by the flow groove and the weakening groove, so that each region has better deformation to better fit the welding of the roll core tab, to ensure the reliability of welding.Simultaneously, the flow groove and the weakening groove also facilitate the flow of electrolyte.

[0027] In the embodiment, the diameter of the welding boss 32 is 1.5-2 times the diameter of the battery roll core center hole.Thus, the welding area between the polar plate and the busbar can be increased, and the welding area between the busbar and the roll core tab is ensured.

[0028] An annular riveting piece 4 is provided between the electrode plate 2 and the annular end plate 11. The cross-section of the riveting piece 4 is "I"-shaped, and it is riveted to the electrode plate 2 and the annular end plate 11 respectively. An insulating pad with a first insulating element is provided between the riveting piece 4 and the annular end plate 11, and an insulating pad with a second insulating element is provided between the riveting piece 4 and the electrode plate 2. The first insulating element includes a first insulating pad 12 disposed on the inner side of the annular end plate 11. A first flange protruding from the middle of the first insulating pad 12 is provided to mate with the inner hole of the annular end plate 11. The outer diameter of the first insulating pad 12 matches the inner diameter of the housing 1. The first insulating pad can form an insulating barrier between the busbar and the housing to avoid short circuits. The outer side of the annular end plate 11 has an annular first insulating ring 13, and the inner side of the first insulating ring 13 is connected to the first flange. The second insulating element includes a second insulating pad 14 disposed on the inner side of the electrode plate 2. The outer edge of the second insulating pad 14 is provided with a second flange that cooperates with the edge of the electrode plate 2. The outer side of the electrode plate 2 has a second insulating ring 15 in the shape of an annular ring. The outer diameter of the second insulating ring 15 is consistent with the outer diameter of the second insulating pad 14 and is connected to the second flange.

[0029] The outer diameter of the first insulating ring 13 matches the outer diameter of the riveting piece 4 and has an outwardly protruding flange; the inner diameter of the second insulating ring 15 matches the inner diameter of the riveting piece 4 and has an outwardly protruding inner flange, the heights of the outer and inner flanges matching the protrusion height of the riveting piece 4. The first insulating ring 13 and the second insulating ring 15 are made of PPS plastic; the first insulating pad 12 and the second insulating pad 14 are made of fluororubber.

[0030] In this embodiment, the cylindrical battery has a welding boss that is welded to the electrode plate, thereby increasing the welding area between the electrode plate and the busbar. The welding boss itself is formed by deep drawing, and its edge also has a large flow area with the busbar body, which can reduce internal resistance and temperature rise rate, reduce the risk of battery failure, and improve battery performance.

[0031] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A power-type cylindrical battery positive electrode assembly, characterized in that, The application relates to a power type cylindrical battery positive electrode assembly, which comprises a shell (1) with an open end, an annular end plate (11) formed by extending radially inward at the other end of the shell (1), a polar plate (2) concentrically arranged at the middle part of the annular end plate (11), and a bus bar (3) arranged at the inner side of the polar plate (2).

2. The power prismatic battery positive electrode assembly of claim 1, wherein, The diameter of the polar plate (2) is 1.5-2 times the diameter of the central hole of the battery winding core.

3. The power prismatic battery positive electrode assembly of claim 1, wherein, A riveting sheet (4) in the shape of a ring is arranged between the polar plate (2) and the annular end plate (11), the cross section of the riveting sheet (4) is in the shape of a "H" and the riveting sheet (4) is riveted to the polar plate (2) and the annular end plate (11) respectively, and a first insulating piece is arranged between the riveting sheet (4) and the annular end plate (11).

4. The power prismatic battery positive electrode assembly of claim 3, wherein, The first insulating piece comprises a first insulating pad (12) arranged at the inner side of the annular end plate (11), a first flange protrudingly arranged at the middle part of the first insulating pad (12) and matched with the inner hole of the annular end plate (11), and a first insulating ring (13) arranged at the outer side of the annular end plate (11) and matched with the first flange.

5. The power prismatic cell positive electrode assembly of claim 4, wherein, The outer diameter of the first insulating pad (12) is matched with the inner diameter of the shell (1).

6. The power prismatic cell positive electrode assembly of claim 4, wherein, A second insulating piece is arranged between the riveting sheet (4) and the polar plate (2).

7. The power prismatic battery positive electrode assembly of claim 6, wherein, The second insulating piece comprises a second insulating pad (14) arranged at the inner side of the polar plate (2), a second flange protrudingly arranged at the outer edge of the second insulating pad (14) and matched with the edge of the polar plate (2), and a second insulating ring (15) arranged at the outer side of the polar plate (2) and matched with the second flange.

8. The power prismatic battery positive electrode assembly of claim 7, wherein, The outer diameter of the first insulating ring (13) is matched with the outer diameter of the riveting sheet (4) and an outwardly protruding flange is arranged at the outer diameter of the first insulating ring (13), the inner diameter of the second insulating ring (15) is matched with the inner diameter of the riveting sheet (4) and an outwardly protruding flange is arranged at the inner diameter of the second insulating ring (15), and the height of the outwardly protruding flange and the inwardly protruding flange is matched with the protruding height of the riveting sheet (4).

9. The power prismatic battery positive electrode assembly of claim 8, wherein, The first insulating ring (13) and the second insulating ring (15) are made of PPS plastic, and the first insulating pad (12) and the second insulating pad (14) are made of fluorine rubber.

10. A cylindrical battery, characterized by The application relates to a power type cylindrical battery positive electrode assembly, which comprises a shell (1) with an open end, an annular end plate (11) formed by extending radially inward at the other end of the shell (1), a polar plate (2) concentrically arranged at the middle part of the annular end plate (11), and a bus bar (3) arranged at the inner side of the polar plate (2).

Images