Research Of The Derived Analytical Method About Lithium Difluorosulfonimede Intermediate

Lithium batteries are widely used in renewable energy storage,electric vehicles,aerospace,military and other fields because of their high energy density,fast charging,high voltage,high cycle life and no pollution.Especially in the new energy automotive industry,since the new century,China's lithium battery technology has gradually broken through the market monopoly and technical blockade of the United States,Japan and other European countries.In recent years we completely ignores the faces of Americans and Japanese.Catching up and blasting the US and Japan's new energy market share.China's lithium battery capacity will occupy 2/3 of the world's market in 2020,and truly achieving a corner overtaking in the automotive sector.At present,the most widely used lithium-ion battery in the market is lithium hexafluorophosphate.Due to the poor thermal stability of lithium hexafluorophosphate,even a small amount of moisture,some anions(such as chloride ion,sulfate ion)have a great destructive effect on the electrolyte.Compared with lithium hexafluorophosphate,Lithium difluorosulfonimide has obvious advantages such as faster charging and no phosphorus pollution.It is a general trend to replace lithium hexafluorophosphate in the current market.Whether lithium difluorosulfonimide or lithium hexafluorophosphate is analyzed by appearance,water content,acid value,solvent residue,anion content(chloride ion,fluoride ion,sulfate ion,amino sulfonate ion plasma anion),cation content(sodium,potassium,calcium,iron and other metal separation).Content and other indicators for monitoring.This text mainly elaborates the anion detection(other quality index analysis methods are very mature).At present,the intermediate control reaction conditions are determined by ion chromatography.This method is very convenient for the detection of fluoride ions,chloride ions and sulfate ions,but it is easy to hydrolyze dichlorosulfonyl imide.The detection data of chloride sulfate ion and sulfamic acid ion are easily distorted,while the ion radius and polarization of difluorosulfonimide ion are very large,which makes ion chromatography unable to wash this anion.By deriving dichlorosulfonimide ion and aniline under certain conditions,benzene-containing derivatives which can be detected by ordinary liquid phase can be produced.At the same time,the corresponding standard products can be prepared to quantify dichlorosulfonimide ion.