Publication

Power and Mobility (P&M)
2023

SOME INSIGHTS IN FAST CHARGE METHODS FOR NCA CELLS

by Bapiraju Surampudi; Ian Smith; Terry Alger

Abstract

Low charge times are very desirable for battery electric vehicles. Lithium Nickel Cobalt Aluminum (NCA) chemistry is used in vehicles like the Tesla Model S for their energy density and also used in several consumer applications. Investigators used state of art NCA cells to conduct research into the tradeoffs between charge time, life and safety. Eight different charge profiles were compared. These included the standard CC-CV strategy and the state of the art Tesla Model S profile. Impact of temperature is also embedded in the selection of charge profiles. A non-dimensional charge metric is proposed as a composite of the impacts of charge time, effective charge stored, aging, overcharge sensitivity and lithium plating sensitivity. This metric is computed for all tested charge profiles and the best candidates are identified.