Structural regulation chemistry of lithium-ion solvation in nonflammable phosphate-based electrolytes for high interfacial compatibility with graphite anode

With the booming development of lithium-ion batteries,safety has become one of the most primary focuses of current researches.Although there are various approaches to enhance the safety of lithiumion batteries,phosphate-based electrolyte holds the greatest potential for practical application due to their non-flammability.Nonetheless,its compatibility issue with the graphite anode remains a significant obstacle to its widespread use.Herein,an effective method is proposed to improve the compatibility of electrolyte with graphite(Gr)anode by rationally adjusting the proportion of lithium salt and solvent components to optimize the Li^(+)solvation structure.By slightly increasing the Li^(+)/triethyl phosphate(TEP)ratio,TEP alone cannot fully occupy the inner solvation sheath and therefore less polar ethylene carbonate(EC)has to be recruited,and the solvation structure gradually changes from Li^(+)–[TEP]_(4)to Li^(+)–[TEP]_(3)[EC]with the coexistence of EC and TEP.Simultaneously,EC molecules in the Li^(+)–[TEP]_(3)[EC]could be preferentially reduced on graphite compared to the TEP molecules,resulting in the formation of a uniform and durable solid-electrolyte interphase(SEI)layer.Benefiting from the optimized phosphate-based electrolyte,the Gr|Li battery exhibits a capacity retention rate of 96.8%after stable cycling at 0.5 C for 470 cycles which shows a longer cycle life than the battery with carbonate electrolyte(cycling at 0.5 C for 450 cycles).Therefore,this work provides the guidance for designing a non-flammable phosphate-based electrolyte for high-safety and long cycling-life lithium-ion batteries.

Investigating TEP as a greener alternative to NMP in Ni-rich cathode fabrication

In the past decade,the surging demand for portable electronics,electric vehicles,and stationary energy storage grids has triggered a noticeable rise in the production of Li-ion batteries(LIBs).However,this swift rise is now hindered by relying on the use of N-methyl-2-pyrrolidone(NMP),a repro-toxic solvent,in the current cathode processing of LIBs.To overcome this challenge,here we have investigated triethyl phosphate(TEP) as a greener alternative to NMP.The compatibility with polyvinylidene fluoride(PVDF)binder,the slurry rheology,the electrode morphology and cell performance with Ni-rich cathodes are characterized.The results show that TEP-based samples possess indistinguishable characteristics in all as pects studied when compared with NMP,revealing that TEP is a promising substitute for NMP in processing Ni-rich cathodes.It is anticipated that this green solvent,TEP,will draw attention from industry in the real-world LIB application in the future.

Thiamine hydrochloride(VB1):An efficient catalyst for one-pot synthesis of α-aminophosphonates under ultrasonic irradiation

An efficient synthesis of novelα-aminophosphonates by the reaction of aldehydes and amines with triethyl phosphite in the presence of the easily available,inexpensive,and nontoxic catalyst thiamine hydrochloride（VB1）.This method affords theα-aminopho-sphonates under the influence of ultrasound irradiation in aqueous medium,in short reaction times（4-6 min）,high yields（85-95%）, with improved purity.The process is green,mild,inexpensive and excellent yields are the main compensation of this procedure.