Reserve Capacity
WARNING: This page is about a different car, the 2004 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.
The RC is an indication of the battery's ability to produce a relatively low amount of current over a long period of time. The RC rating is the amount of time in minutes it takes a fully charged battery at 27°C (80°F) to reach a terminal voltage of 10.5 volts when it is being discharged at a constant rate of 25 amperes. Refer to Battery Usage for the reserve capacity rating of the original equipment battery.