A car is plugged in at a charging point for electric vehicles in London, Britain, March 6, 2018. REUTERS/Simon Dawson/FILE PHOTO (Corrects story and headline to say makers pledge $11.3 billion, not $14.3 billion for lithium iron phosphate plants) Interest and investment in lithium iron phosphate (LFP) battery cells and materials, used to power electric vehicles, continue to climb in the United States. LFP is a lower-cost competitor to nickel cobalt manganese cells.