State of charge, SOC
WARNING: This page is about a different car, the 2002 Volvo C70, 2001 Volvo C70, 2000 Volvo C70, 1999 Volvo C70, and 1998 Volvo C70. However, it is still accessible from the selected car via links, so may be relevant.
The state of charge is expressed as the amount of electrical energy that is stored in the battery at any given time, in relation to how much energy can be stored in a fully charged battery. The state of charge is listed as a percentage of full charge. This is the "State of Charge", SOC.