A Novel Phosphate-Based Flame Retardant and Film-Forming Electrolyte Additive for Lithium Ion Batteries

Materials for lithium-ion battery safety

“…As halogens are hazardous to the environment and human health, the organic phosphorus compounds are more promising candidates as flame-retardant additives because of their high flame-retarding ability and environmental friendliness. Typical organic phosphorus compounds include trimethyl phosphate ( 87 ), triphenyl phosphate ( 89 ), bis(2-methoxyethoxy)methylallylphosphonate ( 90 ), tris(2,2,2-trifluoroethyl) phosphite ( 91 ), (ethoxy)pentafluorocyclotriphosphazene ( 92 ), ethylene ethyl phosphate ( 93 ), etc. ( Fig.…”

Rational design on separators and liquid electrolytes for safer lithium-ion batteries

“…The organic phosphorous compounds are more promising as flame retardant additives due to their high flame-retarding ability and environmental-friendliness, whereas the halogens are proven to be hazardous to the environment and human health. Typical organic phosphorus-containing compounds include phosphates [71,72] , phosphonates [73] , phosphites [74] , cyclotriphosphazenes [75] , etc. ( Fig.…”

“…To solve this problem, the molecular structures of these flame retardants have been modified: (1) use flame retardants that contain polymerizable or reductive groups, such as bis(2-methoxyethoxy)methylallylphosphonate [73] and tris(2,2,2trifluoroethyl) phosphite) [74] , where the polymerizable allylic groups in the former and the P(III) phosphites in the latter can facilitate SEI formation on electrode to protect the electrode from hazardous side reactions while preserving the flame-retardant function. (2) Fluorination of the alkyl phosphates to improve their electrochemical stability [74] , as the enrichment of fluoride components, such as LiF, is well recognized to be beneficial to stabilize the SEI of anode.…”

Fluorinated Hyperbranched Cyclotriphosphazene Simultaneously Enhances the Safety and Electrochemical Performance of High‐Voltage Lithium‐Ion Batteries

“…[9] Organophosphorus compounds ( Figure S1 ai nt he Supporting Information) have been utilized as flame-retardants, owing to their self-extinguishing properties. [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] At elevated temperatures, they generate free radicals including PO· to scavenge the ·H and ·OH radicals produced from organic solvents to form phosphoric acids, which are finally converted to chars that act as at hermally insulating barrier. [5,[25][26][27] However,o rganophosphorus compounds often lead to considerable electrochemicald ecomposition of the electrolytes, thereby presenting at rade-off between fire retardation and electrochemical performance.…”

“…[5,[25][26][27] However,o rganophosphorus compounds often lead to considerable electrochemicald ecomposition of the electrolytes, thereby presenting at rade-off between fire retardation and electrochemical performance. [21][22][23][24] Recently,t he von Cresce and Xu reported ah ighly fluorinated phosphate compound, tris(hexafluoroisopropyl) phosphate (HFiP), as an electrolyte additive to stabilize both the LiNi 0.5 Mn 1.5 O 4 cathode and the graphite anode (Figure S1 b). [28] Although the use of 1% HFiP enhanced the electrochemical performances of the electrodes, this amount does not seem to be enough to guarantee thermal stabilityo ft he electrolytes and the electrodes at high temperatures.…”