Alternating Current (AC) is the type of electrical power supplied by most household outlets. Unlike Direct Current (DC), which flows in one direction, AC reverses its direction multiple times per second (measured in Hertz, Hz). EV batteries store power as DC, so when charging from an AC source, the EV must use an onboard converter to change the AC into DC. AC charging is typically slower than DC fast charging because of the conversion process and lower power levels.
