Cells and Cell Systems

Power cells 

Power cells mainly include lithium ion cells, lead acid cells, nickel cadmium cells, nickel hydrogen cells, solar cells and fuel cells. Lithium ion cells are the most important variety of power cells today and also represent the major development direction of power cells in the future. In recent years, China has issued quite a few policies to encourage and support the development of power cell sector, such as theNotice of the State Council on Issuing the Energy-Saving and New Energy Vehicles Industry Development Plan(2012-2020), theGuiding Opinions on Accelerating the Promotion and Application of New Energy Vehiclesand theGuideline for Developing Electric Vehicle Charging Infrastructure(2015-2020). The output of new energy vehicles in China was 78, 000 units in 2014, 379, 000 units in 2015 and 517,000 units in 2016. The rapid development of the new energy vehicle sector has also promoted the development of power cell sector and related sectors. 

Cathode materials 

Cathode materials used in power cells mainly include lithium ion phosphate, ternary materials and lithium manganate. Cathode materials determine the safety property of cells and also the possibility for large-scale production. Lithium iron phosphate is easily available and has good recycle and safety properties, but its conductivity is poor. Ternary materials have good properties, but the manufacturing process conditions are demanding and the cost is high. Lithium manganate costs low and has good safety property, but the service life of cells is quite low.  

Anode materials 

Anode materials are classified into carbon materials (graphite carbon materials and non-graphite carbon materials) and non-carbon materials. Graphite materials have extensive sources and low price and also play an important role in the safety property of cells. They are mainstream anode materials for lithium ion cells today. Production technologies for anode materials are quite well developed. Lithium ion cell anode materials produced in China occupy a high share in the global market.  

Electrolyte 

Cell electrolyte fluids are called the “blood” of cells. They perform ionic conducting function between cathodes and anodes of cells. They are usually made of high-purity organic solvents (carbonates, etc.), electrolyte salts (lithium hexafluorophosphate, etc.), additives (film forming additives, flame-retardant additives, overcharge protection additives, etc.) and other raw materials. China is one of the major cell electrolyte suppliers in the world. In the past decade, cell electrolyte technologies developed rapidly in China, relevant technologies regarding electrolyte formulas, raw materials and product quality have been constantly upgraded.  

Diaphragms 

Diaphragms are key interior components of lithium ion cells. They are important parts to protect the safety of end cells. They are used to prevent shortcuts caused by the contact between cathode and anode materials. Production processes for diaphragm materials are quite complicated. Dry process and wet process are the two key ones used. Polyolefin diaphragms are the dominant products in the market today.  

Resources 

Resources used in power lithium ion cells include graphite, lithium, cobalt and nickel, etc. As China accelerates the development of new energy vehicles, the demand of mineral resources in power cells will keep increasing in the future.