摘要
Abstract: Lithium iron phosphate (LiFePO 4 ) is recognized as being less stable and easily dissolvable in aqueous suspensions, particularly when the suspension pH is adjusted to be more alkaline or acidic. In this investigation, an unexpected and interesting finding is revealed, which contradicts the conventional understanding of the dissolution of LiFePO 4 . As most of the surface of commercial LiFePO 4 is coated with carbon, the key factor determining its dissolution behavior is the chemical quality of the surface carbon. With more sp 2 -bonded carbon on the surface, both the dissolution and electrochemistry of LiFePO 4 are independent of pH variations in aqueous suspensions. When the surface carbon is mainly sp 3 -bonded, LiFePO 4 exhibits distinct dissolution and electrochemical properties at different pH levels and, under alkaline conditions, shows greater dissolution and poorer cell performance than that characterized mainly by sp 2 -bonded carbon. Graphical Abstract: [Figure not available: see fulltext.].