CN204947019U - A kind of full lug column lithium ion battery - Google Patents

Abstract

The utility model discloses a cylindrical all-tab lithium ion battery structure. Including housing (5), positive electrode current collector (4), negative electrode current collector (6), positive electrode cover plate (2), negative electrode cover plate (8), positive electrode pole (1) and negative pole pole (7) , characterized in that the positive cover plate (2) and the positive pole (1) are a positive assembly, the positive current collector plate (4) is welded to the flattened part of the positive terminal surface, and the negative current collector plate is welded to the flattened part of the negative terminal surface (6); the positive pole (1) is connected to the positive current collector (4) in a threaded manner, and the negative pole (7) is connected to the negative current collector (6) in a threaded manner. The utility model connects the positive and negative poles with the positive and negative current collectors through screw connection, and uses two liquid injection holes to realize the functions of fast liquid injection and elimination of gas production after chemical formation, simple process and small internal resistance , The rate cycle performance is good, and the degree of automation is high, and the service life of the battery can be improved.

Description

A kind of all-tab cylindrical lithium-ion battery

【Technical field】

The invention relates to a lithium-ion battery assembly technology, in particular to a full-tab cylindrical lithium-ion battery assembly structure.

【Background technique】

As a green and environmentally friendly new energy source, lithium-ion batteries have the advantages of good reliability, high safety, small size, and light weight. They are widely used in electronic products, electric vehicles, military products and other fields. With the improvement of power performance requirements of electric vehicle systems, lithium-ion batteries are developing towards high power and high rate.

Cylindrical batteries are popular because of their winding processing, simple structure, and high production efficiency. At present, the gap coating method is mostly used for cylindrical batteries, and the tabs are welded to the foil coating gap of the pole piece. Generally, 2-5 tabs are welded on a single pole piece, and finally all the tabs are welded to the same current collector. This process The process is complicated, time-consuming and low in production efficiency. In addition, due to the many welding structures, the tabs are prone to false welding and over-soldering, resulting in excessive internal resistance of the battery, and the service life is not up to standard, and the current distribution of the gap tabs is uneven, the transmission path is long, and the resistance is large, which is difficult to meet the requirements of the industry. High-rate charge and discharge performance requirements for power lithium-ion batteries.

【Content of invention】

Aiming at the above problems, the present invention provides a cylindrical lithium battery structure with all tabs to improve the high rate charge and discharge capacity of the battery, reduce the welding process in the assembly of the battery structure, improve product quality, ensure the product qualification rate, and reduce human-induced damage. of defective products. Its scheme is as follows:

A cylindrical lithium-ion battery, comprising a housing (5), a positive current collector (4), a negative current collector (6), a positive cover (2), a negative cover (8), a positive post (1 ) and negative pole pole (7), it is characterized in that, described positive pole cover plate (2) and positive pole pole (1) are positive pole assemblies, positive pole current collecting plate (4) is welded at the flat place of positive pole surface, negative pole surface The negative electrode current collecting plate (6) is welded at the vibration level; the positive electrode pole (1) is connected with the positive electrode current collecting plate (4), and the negative electrode pole (7) is connected with the negative electrode current collecting plate (6).

Preferably, the positive electrode assembly is connected by plastic heat riveting and made of PFA or PPS.

Preferably, the positive column head (1) and the negative column head (7) have external threads (10). There are internal threads (14) in the center of the positive electrode current collecting plate (4) and the negative electrode current collecting plate (6).

Preferably, the thread length is ≥4mm.

Preferably, the positive column head (1) is provided with a liquid injection hole 1 (11), the inner end of the liquid injection hole 1 (11) communicates with the inner cavity of the battery and a steel ball is built in the liquid injection hole 1.

Preferably, a groove (12) is provided on the positive cover plate, and the groove (12) is welded with the liquid injection nozzle (3) to form a liquid injection hole 2, and the inner end of the liquid injection hole 2 is connected to the inner cavity of the battery And a steel ball is built in the liquid injection hole 2.

Preferably, a welding position (15) is provided on the collector plate, and the thickness of the welding position (15) is 0.5-2.5 mm.

Preferably, the upper end surface of the positive electrode current collecting plate (4) is in close contact with the lower end surface of the positive electrode column (1), and the upper end surface of the negative electrode current collecting plate (6) is in close contact with the lower end surface of the negative electrode column (7).

Preferably, the structural material of hardware used in the entire battery is metal.

Beneficial effects of the present invention:

The process of the present invention adopts the screw fit method to connect the battery current collector plate and the pole, and the contact internal resistance is very small, which not only retains the large current output capability of the full-tab battery, but also reduces the welding process. At the same time, the present invention adopts two A liquid injection hole structure realizes the function of fast liquid injection and discharge of exhaust gas. The invention has simple structure, high production efficiency, and improves the battery life while improving the electrical performance such as battery rate cycle.

【Description of drawings】

Accompanying drawing 1 is the assembled structural diagram of lithium ion battery of the present invention

Accompanying drawing 2 lithium-ion battery positive electrode cover assembly of the present invention

Accompanying drawing 3 Lithium-ion battery cathode cover plate assembly collector plate front according to the present invention

Accompanying drawing 4 lithium-ion battery positive electrode cover plate assembly collector plate back according to the present invention

【detailed description】

The specific embodiment of the present invention will be further described below in conjunction with accompanying drawing:

Figure 1 shows the overall structure of the battery, including a housing (5), a positive current collector (4), a negative current collector (6), a positive cover (2), a negative cover (8), and a positive post ( 1) and negative pole pole (7), liquid injection hole (11) (12), safety valve (13).

The invention is an all-tab cylindrical lithium ion battery. The specific assembly process of the battery is as follows:

1. The positive cover plate (2) and the positive pole (1) are an assembly (Fig. 2), which are connected by plastic thermal riveting. The thermal riveting uses plastic PFA (9) (soluble polytetrafluoroethylene), which can ensure thermal riveting The structure has sufficient chemical corrosion resistance and creep resistance, etc.;

2. Flatten the parts that need to be welded at both ends of the cell with a lug shaping machine, and press them into a rice-shaped or cross-shaped (corresponding to the shape of the current collector), and then weld the positive current collector on the flattened part of the positive end surface ( 4) Weld the negative electrode current collector plate (6) at the flattened part of the negative terminal surface, and the thickness of the welded part is 0.5mm, which not only ensures the strength of the welding, but also reduces the weight of the battery and improves the energy density of the battery;

3. The positive electrode current collecting plate (4) and the negative electrode current collecting plate (6) are processed with internal thread (14) at the center, and the positive electrode column head (1) and the negative electrode column head (7) have external thread (10). Connect the positive end of the cell welded with the collector plate to the positive cover plate assembly (Figure 2) in a threaded manner, and connect the negative end to the negative pole (7) in a threaded manner. The length of the threaded connection is ≥ 4mm to ensure the connection reliability.

4. Weld the negative cover plate (8) and the shell (5), then put the cell assembly connected in step 4 into the shell, and put the positive cover plate and the shell, that is, the seam between the positive cover plate and the shell Welding at the place, and a safety valve is set on the positive cover plate to ensure safety.

5. Finally, weld the joint between the negative electrode pole (7) and the negative electrode cover plate (8).

6. After the assembly is complete, check the battery for leaks.

7. Liquid injection process: there is a liquid injection hole 1 (11) on the positive column head (1), the bottom of the liquid injection hole leads to the inner cavity of the battery, there is a groove (12) on the positive electrode cover plate, and the groove (12) is connected to the injection hole. The liquid nozzle (3) is welded to form a liquid injection hole 2; the liquid injection hole 1 is connected to the liquid injection system for liquid injection, and the liquid injection hole 2 is connected to the vacuum system for exhaust gas during vacuuming and formation during the liquid injection process; After liquid injection, the injection hole 1 is sealed with a steel ball, and the injection hole 2 is sealed with a sealing cap. The sealing method of the injection hole 2 can be a thread seal or a pagoda joint seal, so as to facilitate subsequent opening and exhaust.

8. During formation, the liquid injection hole 2 can be removed from the sealing cap and connected to an external pipeline for exhaust or after formation, the sealing cap can be removed and exhausted in a vacuum box. After exhausting, the liquid injection hole 2 can be sealed with steel balls.

Claims (9)

1. a column lithium ion battery, comprise housing (5), anode collection plate (4), negative pole currect collecting plate (6), positive pole cover plate (2), negative pole cover plate (8), Positive Poles (1) and negative pole pole (7), it is characterized in that, described positive pole cover plate (2) and Positive Poles (1) are positive pole sub-assembly, positive pole end face shakes flat place's welding anode collection plate (4), and negative pole end face shakes flat place's welding negative pole currect collecting plate (6); Described Positive Poles (1) is connected with anode collection plate (4), and negative pole pole (7) is connected with negative pole currect collecting plate (6).

2. column lithium ion battery according to claim 1, is characterized in that: described positive pole sub-assembly, with plastic hot riveting method connect and material for PFA or PPS.

3. column lithium ion battery according to claim 1, it is characterized in that: described positive pole column cap (1) and negative pole column cap (7) have external screw thread (10), there is internal thread (14) at anode collection plate (4) and negative pole currect collecting plate (6) center.

4. column lithium ion battery according to claim 3, is characterized in that: described reach >=4mm.

5. column lithium ion battery according to claim 1, it is characterized in that: described positive pole column cap (1) is provided with liquid injection hole 1 (11), described liquid injection hole 1 (11) the inner is communicated with battery compartment and is built-in with steel ball at liquid injection hole 1.

6. column lithium ion battery according to claim 1, it is characterized in that: described positive pole cover plate is provided with groove (12), form liquid injection hole 2 after groove (12) welds with liquid injecting mouth (3), described liquid injection hole 2 the inner is communicated with battery compartment and is built-in with steel ball at liquid injection hole 2.

7. column lithium ion battery according to claim 1, is characterized in that: described collector plate is provided with welding position (15), and welding position (15) thickness is 0.5-2.5mm.

8. column lithium ion battery according to claim 1, it is characterized in that: anode collection plate (4) upper surface and positive terminal (1) lower surface close contact, negative pole currect collecting plate (6) upper surface and negative terminal (7) lower surface close contact.

9. column lithium ion battery according to claim 1, is characterized in that: the hardware structure material that described whole battery is used is metalwork.