Square winding type battery pole piece and manufacturing technology thereof

Abstract

The invention belongs to the technical field of battery structures, and discloses a square winding type battery pole piece. One edges of positive and negative current collectors are provided with convex electrode lugs; the roots of the convex electrode lugs are provided with insulation rubber coatings; two side edges of the positive current collector are provided with positive electrode small white spaces; two side edges of the negative current collectors are provided with negative electrode small white spaces; the positive electrode small white spaces and the negative electrode small white spaces are oppositely adhered with insulation tapes; a big white space is arranged between a positive electrode coating region and the positive electrode small white space at one side edge; the big white space provides larger coating amount of positive active substances, increases capacity of the battery, and reduces cost of the battery. The insulation rubber coatings are tightly combined with the coating material on the convex electrode lugs, thereby increasing the strength of the electrode lugs and playing a role of preventing shore-circuit situation during a pole-lug folding process. By cutting in the position where the insulation tapes are oppositely adhered during a winding process, powder off caused by cutting the material and burr short circuit caused by a cutter can be prevented effectively.

Description

technical field [0001] The invention belongs to the technical field of battery structures, and relates to a square wound battery pole piece and a manufacturing process thereof. Background technique [0002] The shortage of fossil energy, environmental pollution, and climate warming have become common issues faced by all mankind. 70% of my country's oil is used for automobiles, 50% of urban air pollutants come from automobiles, and the dependence on foreign crude oil has exceeded 50%. The development of new energy vehicles is a strategic need to get rid of dependence on fossil energy such as petroleum, protect the ecological environment and ensure national energy security. [0003] Electric vehicles are the focus of the development of new energy vehicles, and power batteries are the core components of electric vehicles. The development of new energy vehicles has opened up a broader space for the development of my country's power battery industry, and lithium-ion batteries a...

AI Technical Summary

Problems solved by technology

Due to the design of the tabs, the laminated battery has high-rate performance due to the tabs on each laminate, but the processing technology of the laminated battery is complicated, the process is cumbersome, and the quality control of process burrs is relatively strict. limited by processing shortcomings

In contrast, the wound-type battery has a simple preparation process and can be fully automatic and mass-produced, so it develops relatively rapidly. Around the disadvantage of its poor rate performance, many emerging designs have also appeared in the battery structure, such as single-pole multiple The structural design of the winding core can improve the rate performance of the battery, but this structure reduces the capacity performance of the battery due to the need to reserve space for blank current-collecting structures such as tabs and blanks on the first roll

There is also the form of outsourcing the diaphragm with multi-pole structure of positive and negative electrodes. The battery with this structure has high rate and capacity performance, but the dressing position is generally cut during the winding process of the battery core, resulting in a large amount of dust and positive ears. The unprotected folding process is relatively easy to cause short circuit of the battery cell and relatively easy to break the tab during the production process. Certain protective measures are required. Based on this, the form of laser cutting the negative electrode and spot welding the positive electrode and pasting the tab is derived. , to a large extent solved the short-circuit problem of the battery cell, but the tab position of the spot welding occupies a certain dressing position, which reduces the capacity of the battery to a certain extent

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