1.5V (DC) - A common open circuit voltage for non-rechargeable alkaline batteries (e.g. AAA, AA and C cells). u003cbr/u003e3.8V (DC) - Almost all smartphone batteries work at 3.8 volts. In order to make current flow from the charger to the battery, there must be a potential difference. Therefore battery chargers or USBs for almost all smartphones provide a voltage of 5V.u003cbr/u003e12V (DC) - A common voltage for automobile batteries is 12 volts (DC).u003cbr/u003e110 - 120V (AC) - The most common electrical outlet in any home. The American continent uses a voltage of 110 to 120 volts (AC) while Europe, Asia and Africa use 220 to 240 volts (AC).