CN202034444U - Lithium ion power battery - Google Patents

Abstract

The utility model provides a lithium-ion power battery, the electric field of the electric core is evenly distributed, the internal resistance of the battery is small, the specific power is large, and the requirement for realizing high-rate discharge is met. It includes a battery core and a casing surrounding the battery core. The battery core includes multiple positive electrode sheets, separators and negative electrode sheets that are arranged and connected in a winding or superimposed manner, and the separator is spaced between adjacent positive electrode sheets and negative electrode sheets; It is characterized in that: each positive electrode sheet includes a positive electrode tab and a positive electrode current collector, and each negative electrode sheet includes a negative electrode tab and a negative electrode current collector; the battery core also includes a positive electrode plate and a negative electrode plate respectively It is located on both ends of the positive electrode sheet, the separator and the negative electrode sheet; the positive electrode lug extends out of the positive electrode collector and is located in the gap between the positive electrode plate and the positive electrode collector, and the negative electrode ear extends out of the negative electrode collector and is located in the In the gap between the negative electrode plate and the negative electrode current collector.

Description

Lithium-ion power battery

technical field

The utility model belongs to the technical field of lithium-ion power batteries, in particular to a tab structure of a lithium-ion power battery and a connection method thereof.

Background technique

Lithium-ion battery is a new generation of rechargeable battery developed after MH-Ni battery, because of its high working voltage, high energy density, good safety, light weight, small self-discharge, long cycle life, no memory effect, no pollution, etc. Advantages become the key research field of new energy development.

The tab structure commonly used in existing lithium-ion batteries is a tab structure in which a tab is externally connected to the current collector or a tab at the same position is attached to each piece or circle of the current collector, and then stacked together. Due to the small tabs and uneven distribution of the tabs, during high current charging and discharging, the tabs will generate heat due to excessive current, which is likely to cause safety problems. During high-current charging and discharging, if there is an oxide layer or oil on the connection part of the tab or the pole, or the connection between the tab and the pole is loose, it will inevitably cause local overheating, which will cause a safety hazard and make the battery Consistency is poor.

At present, the connection structure between the tabs (or poles) of the power lithium-ion battery and the positive and negative electrodes in the industry is fastened by bolts and welded by ultrasonic waves. The bolt fastening connection is easy to loosen when the battery is subjected to vibration, resulting in increased contact resistance at the connection, deterioration of battery performance, heat at the connection during charging and discharging, and even ignition, which may cause the battery to explode; The process is complex, the cost is high, and the welding of multi-layer plates is not strong.

Contents of the invention

The purpose of the utility model is to provide a lithium-ion power battery, the electric field of the electric core is evenly distributed, the internal resistance of the battery is small, and the specific power is large, which meets the requirement of realizing high-rate discharge.

The utility model is achieved through the following technical solutions:

Lithium-ion battery, including the battery core and the casing surrounding the battery core, the battery core includes multiple positive electrode sheets, separators and negative electrode sheets arranged and connected in a winding or superimposed manner, and the separator is spaced from adjacent positive electrode sheets and negative electrode sheets between; it is characterized in that: each of the positive pole pieces includes a positive pole tab and a positive current collector, and each negative pole piece includes a negative pole tab and a negative current collector; the battery core also includes a positive pole plate and The negative plate is located on both ends of the positive plate, the separator and the negative plate respectively; the positive tab extends out of the positive current collector and is located in the gap between the positive plate and the positive current collector, and the negative tab extends out of the negative current collector and located in the gap between the negative electrode plate and the negative electrode current collector.

The width of the positive current collector is not greater than the width of the negative current collector, and the width of the negative current collector is smaller than the width of the separator.

The thickness of the positive electrode tab is the same as that of the positive electrode current collector, and the thickness of the negative electrode tab is the same as that of the negative electrode current collector.

In sum, the beneficial effects of the present utility model are:

In the lithium ion battery of the present utility model, since each negative electrode sheet all includes a negative electrode tab and a negative electrode current collector; End face; the positive tab extends out of the positive current collector and is located in the gap between the positive plate and the positive current collector, and the negative tab extends out of the negative current collector and is located in the gap between the negative plate and the negative current collector middle. In layman's terms, the lug structure and the connection structure of the lugs provided by the utility model use the blank tape of the current collector as the lug, and do not need external lugs and insulating tape for sealing. The battery with this structure has a specific energy Large, small internal resistance, uniform current distribution, reduces the process of connecting tabs, is conducive to industrial use, and can greatly improve production efficiency. The pole lug and the pole post of the utility model are stamped and sealed with the pole plate with the pole plate through conductive glue, and do not need to be fastened by common bolts or welded by ultrasonic waves, which avoids the shock caused by the bolt fastened connection on the battery When it is easy to loosen, the internal contact resistance of the connection will increase, the performance of the battery will deteriorate, and the connection will heat up during charging and discharging, and even cause the battery to explode; and the use of ultrasonic welding has complex processes, high costs, and Insufficient welding when welding multi-layer plates.

The utility model is suitable for the use of lamination-type or winding-type power batteries. The tab structure of the lithium-ion power battery provided by the utility model has the advantages of easy operation, simple materials, light weight, low cost, high power density, and high production efficiency. High efficiency and other advantages. It is convenient for continuous production in production and greatly improves production efficiency.

Description of drawings

Fig. 1 is the schematic diagram of the cross-sectional structure of the positive electrode tab of the lithium-ion battery of the present invention;

Fig. 2 is a schematic diagram of the lug connection structure of the annular lithium ion battery embodiment of the lithium ion battery of the present invention;

Fig. 3 is a schematic diagram of the tab connection structure of the square or cylindrical lithium ion battery embodiment of the lithium ion battery of the present invention.

Detailed ways

The utility model discloses a lithium-ion battery, which comprises a battery core and a casing surrounding the battery core. The battery core includes a plurality of positive pole pieces, separators and negative pole pieces arranged and connected in a winding or superimposed manner. Between the adjacent positive electrode sheets and negative electrode sheets; it is characterized in that: each positive electrode sheet includes a positive electrode tab and a positive electrode current collector, and each negative electrode sheet includes a negative electrode tab and a negative electrode current collector; the battery core It also includes a positive electrode plate and a negative electrode plate respectively located on the two ends of the positive electrode sheet, separator and negative electrode sheet; the positive electrode lug extends out of the positive electrode collector and is located in the gap between the positive electrode plate and the positive electrode collector. The tab extends out of the negative electrode current collector and is located in the gap between the negative electrode plate and the negative electrode current collector.

The width of the positive current collector is not greater than the width of the negative current collector, and the width of the negative current collector is smaller than the width of the separator.

The thickness of the positive electrode tab is the same as that of the positive electrode current collector, and the thickness of the negative electrode tab is the same as that of the negative electrode current collector.

The width of the positive tab is 2-5mm, and the width of the negative tab is 2-5mm. The material of tabs can be greatly saved and the cost can be reduced.

As shown in Figure 1, the positive electrode sheet is a planar sheet structure when it is unfolded, including the positive electrode tab 1 and the positive electrode current collector 2 connected as a whole, the length and size of the positive electrode tab 1 and the positive electrode current collector 2 are the same, and the width of the positive electrode tab 1 The size plus the width of the positive electrode collector 2 is equal to the width of the positive electrode sheet.

The material of the positive electrode tab 1 is aluminum foil, which is the same as the material of the positive electrode current collector 2; no additional materials are required.

The negative electrode tab material is copper foil or aluminum foil, which is the same as the material of the negative electrode current collector; no additional materials are required.

Embodiment one:

As shown in Figure 2, the lithium-ion battery is a lithium-ion battery with a hollow structure, and the casing includes an outer shell 5 with an annular structure and a hollow inner shell 6 with an annular structure, a positive electrode current collector 2, and a negative electrode current collector 10 It is wound and arranged in parallel with the separator 13 and is located in the cavity between the outer shell 5 and the inner shell 6; the positive electrode plate 4 and the negative electrode plate 12 are both annular sheet structures, covering the two sides of the outer shell 5 and the inner shell 6 respectively. The outer end of each positive pole tab 1 is connected to the positive pole plate 4, and the outer end of each negative pole tab 9 is connected to the negative pole plate 12; the outer end surface of the positive pole plate 4 is provided with more than one positive pole Pillar 3, the positive pole tab 1 and the positive pole pole 3 are connected and conducted through the positive pole plate 4, the positive pole pole 3 is fixed on the positive pole plate 4, and the positive pole plate 4 and the positive pole lug 1 are connected and conducted through the positive pole plate 4. The glue 7 is sealed and connected; the structure and connection method of the negative electrode tab 9, the negative electrode pole 11 and the negative electrode plate 12 are the same as those of the positive electrode.

The positive pole 3 is fixed on the positive pole plate 4 by riveting, and the positive pole plate 4 is sealed and connected to the positive pole lug 1 through the conductive glue 7; the positive pole plate is insulated from the inner shell and the outer shell through the sealant 8, Then, they are fixedly connected by stamping; the structure and connection method of the negative electrode lug, negative electrode pole and negative electrode plate are the same as those of the positive electrode.

Embodiment two:

As shown in Figure 3, the lithium-ion battery is a square or cylindrical lithium-ion battery, including a casing 5, the positive electrode current collector 2, the negative electrode current collector 10 and the separator 13 are arranged in parallel in the cavity of the casing 5; Both the plate 4 and the negative pole plate 12 are sheet-like structures, covering the two ends of the casing 5 respectively, the outer end of each positive pole lug is connected with the positive pole plate 4, and the outer end of each negative pole lug 9 is connected with the negative pole. The pole plate 12 is connected; the outer end surface of the positive pole plate 4 is provided with more than one positive pole pole 3, the positive pole lug and the positive pole pole 3 are connected and conducted through the positive pole pole plate 4, and the positive pole pole 3 is fixed on the positive pole On the pole plate 4, the positive pole plate 4 and the positive pole lug 1 are sealed and connected by the conductive glue 7; the structure and connection method of the negative pole lug 9, the negative pole pole 11 and the negative pole plate 12 are the same as those of the positive pole.

The positive pole is fixedly connected to the positive pole plate by riveting, the positive pole plate is insulated from the shell by sealant, and is sealed and connected by stamping the end of the shell; the negative pole pole is fixedly connected to the negative pole plate by riveting ; The negative electrode plate is insulated from the casing by sealant, and is connected by punching and sealing the end of the stamping casing

The specific implementation methods listed above are non-restrictive. For those skilled in the art, various improvements and changes made within the scope of the present utility model all belong to the protection scope of the present utility model.

Claims (10)

1. lithium-ion-power cell comprises battery and surrounds the housing of battery, comprises in the battery that multi-disc positive plate, barrier film and negative plate adopt coiling or stacked system to arrange and be connected, and barrier film is interval between adjacent positive plate, the negative plate; It is characterized in that: described each sheet positive plate has included positive pole ear and plus plate current-collecting body, and each sheet negative plate has included negative lug and negative current collector; Described battery also includes the both ends of the surface that anode plate and negative plates lay respectively at positive plate, barrier film and negative plate; Positive pole ear extends in the outside and gap between anode plate and plus plate current-collecting body of plus plate current-collecting body, and negative lug is extended in the outside and gap between negative plates and negative current collector of negative current collector.

2. lithium-ion-power cell as claimed in claim 1 is characterized in that: described plus plate current-collecting body width dimensions is not more than the negative current collector width dimensions, and the negative current collector width dimensions is less than the barrier film width dimensions.

3. lithium-ion-power cell as claimed in claim 2 is characterized in that: the thickness of described positive pole ear is identical with the thickness of plus plate current-collecting body, and the thickness of described negative lug is identical with the thickness of negative current collector.

4. lithium-ion-power cell as claimed in claim 2 is characterized in that: the width dimensions of described positive pole ear is 2-5mm, and the width dimensions of described negative lug is 2-5mm.

5. as each described lithium-ion-power cell in the claim 1 to 4, it is characterized in that: during described positive plate deployed condition is the planar sheet structure, include positive pole ear (1) and plus plate current-collecting body (2) connects as one, positive pole ear (1) is identical with the length dimension of plus plate current-collecting body (2), and the width dimensions of positive pole ear (1) adds that the width dimensions of plus plate current-collecting body (2) promptly equals the width dimensions of positive plate.

6. lithium-ion-power cell as claimed in claim 5 is characterized in that: described positive pole ear (1) material is an aluminium foil, and is identical with plus plate current-collecting body (2) material.

7. lithium-ion-power cell as claimed in claim 5 is characterized in that: described negative lug material is Copper Foil or aluminium foil, and is identical with the negative current collector material.

8. lithium-ion-power cell as claimed in claim 5, it is characterized in that: described lithium ion battery is a kind of lithium ion battery of hollow structure, described housing includes the inner casing (6) of the hollow of the shell (5) of loop configuration structure and loop configuration, and plus plate current-collecting body (2), negative current collector (10) and barrier film (13) close wind are arranged the cavity that is arranged between shell (5) and the inner casing (6); Anode plate (4) and negative plates (12) are the annulus laminated structure, be covered in the two ends of shell (5) and inner casing (6) respectively, the outer end of each sheet positive pole ear (1) all is connected with anode plate (4), and the outer end of each sheet negative lug (9) all is connected with negative plates (12); The outer face of anode plate (4) is provided with more than one Positive Poles (3), described positive pole ear (1) is connected conducting with Positive Poles (3) by anode plate (4), described Positive Poles (3) is fixed on the anode plate (4), and described anode plate (4) is tightly connected by conducting resinl (7) with positive pole ear (1); The structure of described negative lug (9), negative pole pole (11) and negative plates (12) and connected mode are with anodal identical.

9. lithium-ion-power cell as claimed in claim 5, it is characterized in that: described lithium ion battery is a kind of square or column lithium ion battery, include shell (5), plus plate current-collecting body (2), negative current collector (10) and barrier film (13) are arranged in parallel and are arranged in the cavity of shell (5); Anode plate (4) and negative plates (12) are laminated structure, are covered in the two ends of shell (5) respectively, and the outer end of each sheet positive pole ear all is connected with anode plate (4), and the outer end of each sheet negative lug (9) all is connected with negative plates (12); The outer face of anode plate (4) is provided with more than one Positive Poles (3), described positive pole ear is connected conducting with Positive Poles (3) by anode plate (4), described Positive Poles (3) is fixed on the anode plate (4), and described anode plate (4) is tightly connected by conducting resinl (7) with positive pole ear (1); The structure of described negative lug (9), negative pole pole (11) and negative plates (12) and connected mode are with anodal identical.

10. lithium-ion-power cell as claimed in claim 8 or 9, it is characterized in that: described Positive Poles is connected by riveted and fixed with anode plate, and described anode plate and housing be by fluid sealant (8) insulation, and be tightly connected by the punching press shell end; Described negative pole pole is connected by riveted and fixed with negative plates; Described negative plates and housing insulate by fluid sealant, and are tightly connected by the punching press of punching press shell end.

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