Batteries play a pivotal role in the development of the renewable energy industry, especially in the fields of new energy vehicles,solar energy, grid-connected FM stations for wind energy power storage, mobile communication base stations, electric logistics vehicles, and so on. 

Each square shell battery shell is composed of a shell and a cover. The battery cover is a key component that seals the shell with the cells, outputs the internal energy, and ensures the safety of the cells. There are strict requirements on the relief pressure, electrical performance, size and appearance of the safety valve.

At present, the common cover plates on the market include riveted pole cover plates, minimalist pole cover plates, and pole injection cover plates. Although there are various types of cover plates, most of them are composed of positive and negative parts and explosion-proof devices, which means that the welding quality will directly determine the performance and safety of the power battery.

Laser welding is an efficient and precise welding method that uses a high-energy-density laser beam as a heat source. It has the characteristics of high speed, small deformation and high precision. For the power battery cover, the laser welding welding parts are mainly various forms of positive and negative column welding, explosion-proof valve welding and pin welding where some covers exist.

• For the welding of positive and negative poles, it is usually CU-CU/AL-AL welding of the same material, and CU-AL negative electrode dissimilar material welding;
• Pin welding, usually copper and aluminum pins;
• In the welding of explosion-proof valve, the common cover plate has explosion-proof valve structure, the main function is to release the pressure of the cell at all times to ensure that the cell does not explode due to excessive internal pressure.

The New Energy Equipment Division  of UW Laser has been working in the power battery and cover plate industry for more than ten years. It has strong independent research and development capabilities, rich practical experience, and advanced technical production equipment.

The rotary welding system used in the 20PPM prismatic cell cover assembly line of UW Laser is suitable for explosion-proof valve welding, pin welding, pressure riveting pole welding/minimal pole welding and other processes. It is stable, efficient and easy to operate. At the same time, it has dual options of galvanometer welding and hybrid welding (different process routes can be selected).

The whole line includes automatic loading and unloading, explosion-proof valve welding, pole spot welding, pole full welding, ultrasonic welding, sealing helium inspection, multi-function inspection and other processes, which can complete the entire cover plate production process of assembly, riveting and welding,to achieve 20PPM standard production with a ≥98% pass-through yield.

• Equipped with a rotary welding table, the X,Y,Z axis of the exit head can move, and it can weld points, straight lines, circles, squares or any plane graphics composed of arcs. It is suitable for explosion-proof valve welding, flip plate welding, pin welding, and riveting pole welding;
• Dual selection of galvanometer welding and composite welding, simple operation, fast welding speed and high precision;
• The entire production line is easy to operate, easy to maintain, and has a high degree of automation. It can implement comprehensive inspection of each process to ensure the quality of finished products, MES traceability, and accurate tracking and inspection of all welding and related process parameters. Industry 4.0 intelligent Kanban realizes visual real-time monitoring of production data.

In addition to the whole line solution, UW Laser can also provide modular equipment solutions to meet the different customized needs of customers.

Key Stations and Advantages of the Production Line

Explosion-Proof Valve Welding

Automatic installation of explosion-proof discs, automatic welding, post-weld inspection, etc., the production capacity is ≥20PPM, and the excellent rate is ≥99.5%.

Pole Spot Welding Machine + Pole Full Welding Machine

Pole feeding, automatic welding, etc., the production capacity is ≥20PPM, and the excellent rate is ≥99%.

Plastic Ultrasonic Welding Machine

Including plastic hot melt under PP, automatic ultrasonic wave, etc., the production capacity is ≥20PPM, and the excellent rate is ≥99.8%.

Cover Plate Helium Detector

Helium detection test module, helium detection NG cache, cover pairing module, etc., the production capacity is ≥20PPM, and the excellent rate is ≥98%.

Multifunctional Testing Machine

Cover material, code scanning, insulation test, resistance test, sticking explosion-proof film, diaphragm inspection, etc., the production capacity is ≥20PPM, and the single-machine pass rate is ≥99.5%.

Finished Cover Inspection Equipment

Weld bead detection, metal detection, bump and blue film internal detection, edge bump, blue film offset detection, etc., the equipment has high stability, the detection and leakage rate are stable below 0.1%, and the false positive rate is stable within 2%. Capacity ≥30PPM, excellent rate ≥99.5%.

As the core supplier of new energy power battery laser welding, UW Laser has many technical reserves related to power battery welding, in the fields of prismatic power battery, pouch battery, cylindrical power battery, blade battery, and so on. Both have deep technical accumulation, and have two business divisions, New Energy Equipment Division and New Energy Vehicle Division, which are dedicated to R&D and production of corresponding equipment and intelligent manufacturing solutions for the power battery industry, and carry out industrialization and marketization promotion.

The company has strong strength. While making unremitting innovation in technology research and development, it actively expands its production capacity.  Committed to becoming the world's leading mainstream supplier of laser welding equipment and intelligent manufacturing solutions, it has built a total of 391,700 square meters of production bases in Shenzhen, Jiangsu, Huizhou, and Yibin, Sichuan, and implements "localized" research and development, production, sales and services.