Electrical terminology
Alternating Current (AC) and Direct Current (DC) describe types of current flow in a circuit. In DC, the electric charge (current) only flows in one direction, whereas electric charge in AC, changes direction, periodically.
AC is used in homes as it cheaper to generate, has less heat losses in transmission and can be converted between high and low voltages easily with transformers.
DC is used to power pretty much anything that runs off of a battery or plugs in to the wall with an AC adapter.
AC EV Chargers
AC Chargers can be a simple three-pin plug in a conventional power outlet (Level 1). Or a home charging station on a dedicated circuit (Level 2). For ongoing use, home chargers are recommended for safety and convenience.
DC EV Chargers
A DC charger powers the vehicle by converting AC from the grid and is many times faster because the converter inside the EV charger is more efficient than converters found inside EVs.
The high upfront costs of DC charging has meant it is mainly built out to serve a fleet of vehicles or public charging, for drivers to top-up the battery and extend the daily operating range. The faster current creates higher temperatures so as a trade-off for longer battery life, DC charging generally stops at around 90% of capacity.
Charging connectors
While older vehicles still use the CHAdeMO connector, Australian vehicle sellers have largely standardised on the Combined Charging Standard (CCS) that supports both DC fast charging and Level 2 AC charging.