AC versus DC

AC charging passes alternating current through the vehicle's onboard charger, which converts it to the direct current the battery stores. DC fast charging bypasses the onboard charger and feeds direct current straight into the battery — which is why it is faster, and why DC hardware is larger and more complex.

Connectors in North America

  • J1772: the standard AC connector found on most non-Tesla EVs.
  • J3400 (NACS): the connector design now being adopted across the industry, supporting both AC and DC.
  • CCS1: a dominant DC fast-charging connector, which shares J1772's AC pins and adds two DC pins.

Why compatibility is more than the plug

A successful session also depends on the communication handshake between vehicle and charger — power levels, limits and safety checks are negotiated before energy flows. That is why RESERVE ships with a J3400 (NACS) interface and CCS1 support, and why the supported vehicle list is published and updated as compatibility grows.