Power battery is the core component of new energy vehicles, lithium battery quality directly determines the performance of new energy vehicles, so its manufacturing process, production equipment has extremely high precision requirements. Lithium battery manufacturing is connected by a process, and its production process is mainly divided into three parts: pole piece manufacturing, cell production and battery assembly.
As an advanced "light" manufacturing tool, laser technology plays an important role in the processing of the front, middle and back sections of the power battery production line due to its high efficiency, precision, flexibility, reliability and stability, low loss of welding material, automation and high degree of safety.
Laser Welding
Laser welding is the use of laser beams on the object to melt and realize the welding process, in the new energy vehicle lithium batteries and battery packs in the manufacturing process, there are more than 20 processes need to be welded to achieve conductive connection or sealing.
Specifically, the laser welding application process includes:
- Pole piece production section - the front section: laser cutting process is applied to the pole piece and diaphragm slitting link.
- Core assembly section - middle: laser welding process is applied to the shell, top cover, sealing nails, pole lugs and other welding links.
- Post-processing section - back section: welding of connecting pieces in battery PACK module.
Laser cutting
Laser cutting is a process that utilizes a high power density laser beam to achieve cutting. Laser cutting has the advantages of no physical wear and tear, flexible cutting shapes, edge quality control, higher accuracy and lower operating costs, which helps to reduce manufacturing costs, improve productivity and significantly shorten the cycle time for die-cutting new products.
Laser cutting specific application process:
In power battery production is mainly used in the first section of the process of battery pole manufacturing link.
Including laser lug cutting and molding of positive and negative electrodes, laser lug cutting, laser lug slitting, and laser cutting of diaphragm; among them, laser lug molding is currently the most important application of laser cutting in the field of lithium battery manufacturing.
Laser marking
In order to better control product quality and trace the entire production information of lithium batteries, it is necessary to store key information (including raw material information, production process and technology, product batch, manufacturer and date, etc.) in the two-dimensional code and mark it on the battery.
Traditional inkjet coding technology is prone to friction, easy to lose information for a long time and other issues, while laser marking has a strong permanence, high anti-counterfeiting, high precision, wear resistance, safety and reliability, etc., can provide the best solution for product quality tracking.
Laser cleaning
In the lithium battery manufacturing process, before welding the lugs, it is necessary to clean off the coating in the area of the lugs to be welded. The main methods for removing the coating are mechanical scraping, styrofoam application and laser cleaning.
Mechanical scraping is easy to damage the lugs, and it is difficult to ensure that the coating is removed cleanly; the Styrofoam method has more processes, high production costs, and is not applicable to anode aqueous slurry.
Laser cleaning, on the other hand, has the advantages of green, high efficiency, good cleaning effect and little damage to copper foil, etc. It is recognized as the preferred method for removing the coating film on the front and back of the anode pole piece of lithium battery, so as to make the copper foil bare and directly carry out the welding of the pole pole lugs.
As a high-precision production process, the application of laser technology effectively improves power battery safety, reliability and service life. Power battery energy density and safety performance, production automation requirements gradually increased, the precision of production equipment, safety and consistency of high requirements.
Domestic new energy power battery ushered in a period of capacity expansion, small blue power guide used in laser cutting equipment, laser welding equipment, lithium battery automatic stacking machine, lithium battery automation packaging equipment, etc., to meet the lithium expansion tide, with small size, simple structure, high degree of automation, cost-effective advantages, can fully replace the screw module, improve lithium equipment precision, capacity and production efficiency.
