Lithium ion battery is an internationally recognized ideal chemical energy source.It has the advantages of small size,large capacitance and high voltage.It is widely used in mobile phones,laptops and other electronic products.The growing field of electric vehicles will bring more development space for lithium ion batteries

　　China and major developed countries in the world have issued many policies to support new energy vehicles

　　The development planning of seven strategic emerging industries,including new energy vehicles,will further promote China's electric vehicles from the policy level.In 2009,the global production of lithium-ion batteries was about 3.05 billion,with a total battery capacity of about 15000 MWh.In recent years,major global automobile manufacturers have launched various types of electric vehicles.In 2013,the lithium battery capacity of electric vehicles reached 14000 MWh,equivalent to 93%of the global small lithium battery capacity in 2009;In 2018,the lithium battery capacity of electric vehicles will reach 45000MWh,which is nearly three times of the global small lithium battery capacity in 2009.The difficulties of lithium iron phosphate mainly focus on product consistency,low temperature performance,etc

　　In addition,the two core technology patents include carbon deposition and carbothermal reduction

　　Lithium manganate has been studied for a long time,and it is the most mature and reliable positive electrode material for power battery at present,without patent restriction.It can be seen from the current selection of mainstream automobile manufacturers in the world that manganese system and ternary system are the first choice.[**]t present,domestic medium and high grade diaphragms are mainly imported,and domestic technical level is still low

　　In terms of conductivity,thermal stability,oxidation resistance and other properties,lithium hexafluorophosphate is the best electrolyte material.[**]t present,China's medium and high-grade electrolytes are almost all imported,and the gross profit rate of lithium hexafluorophosphate is up to more than 60%.Other additives focus on PVDF,NMP,DOP.[**]t present,polyvinylidene fluoride(PVDF)is widely used in industry as the binder for lithium ion batteries,N-methylpyrrolidone(NMP)as the dispersant,and DOP as the plasticizer