Conclusion: Large-capacity square batteries are the development direction of power batteries.

　　Recently, Mr. Chen Henglong, chairman of Suzhou Yimao Electric Bus Co., Ltd. and a PhD from the University of Delaware, delivered a speech entitled "Summary of Mainstream Technology Features of Power Lithium Battery" at the "Power Battery Exchange Conference". The following is the main content of Chen Henglong's speech:

　　The government's strong support for electric vehicles has given birth to the rapid development of power lithium batteries and the rapid expansion of production capacity. In 2014, power lithium batteries survived the low-speed market cultivation period and ushered in the first market peak. In 2015, power lithium batteries rose all the way, and there was a shortage of supply in the second half of the year. At the same time, a large amount of capital began to flow into this field, and there was a large expansion of production capacity.

　　At the same time, in order to ensure the safety of electric vehicles, the state has banned the subsidy for the use of ternary lithium battery in public transportation and related commercial vehicles, and has virtually proposed a focus of battery materials on EVs. In the development process of new energy vehicles, various technical disputes and focuses have been accompanied by each stage of industrial development, and the discussion and judgment of various technologies are often accompanied by stormy waves.

　　Electric vehicle technology: China's pure electric technology is the mainstream, Toyota focuses on hybrid, Nissan pure electric, BYD: pure electric technology, dual-mode technology (plug-in hybrid).

　　battery technology: lithium battery technology, fuel cell technology (HydroyenFeul), metal-air battery technology, etc. The current more mature technology is lithium-ion battery technology.

　　Lithium ion battery: Lithium ion battery system is divided into ternary system, lithium iron lithium oxide system, lithium titanate anode system, carbon nanotubes, graphene addition, and fast charging system. The process is divided into winding technology, lamination technology; cylindrical battery, square battery; soft package technology, aluminum shell technology.

　　Domestic and foreign power batteries are mainly classified according to their appearance: wound cylindrical batteries, laminated soft-pack batteries, laminated aluminum-shell batteries.

　　Process route: The current lithium-ion battery process has two types of batteries, cylindrical and square. The cylinders are mainly represented by 18650 and 26650. The squares are mainly composed of aluminum shell and aluminum-plastic film soft pack. The manufacturing process is divided into winding Process and lamination process, the soft package is mainly lamination process, and the aluminum shell is mainly winding process. At present, a small number of domestic power battery companies also use the soft package winding process. In short, each process has its own advantages and The disadvantage is how to produce the best battery suitable for electric vehicles.

　　Power battery winding and lamination process comparison:

　　Comparison of 　　 soft pack lamination and aluminum shell lamination:

　　Comparison of different single-unit modules: According to the effects of the two PACK processes, aluminum-shell batteries can be directly assembled into power battery packs, while soft-package batteries need to be reinstalled in a metal or plastic shell with relatively high mechanical strength and good heat dissipation. For PAKC application again, this process considerably increases the cost and process complexity.　　Main domestic and foreign power battery companies and product forms:

　　New energy vehicle goals for major countries in 2020:

　　According to 5 million vehicles, 200 million KWH batteries are required.　　 Conclusion: Large-capacity square batteries are the development direction of power batteries. In Japan, the 18650 cylindrical battery is the main and fully automated production equipment, which is derived from the mature nickel-hydrogen battery industry; in China, the development of fully automated manufacturing equipment for large-capacity batteries, the continuous development and maturity of the process route, guarantees the large The quality, consistency, and safety of the capacity battery also ensure the implementation of the power group technology.