Ampere-Hour (Ah) describes what aspect of a battery?

• A. Describes the charge capacity of a battery, or how much current can be delivered at a constant rate as the battery is depleted over the course of one hour.
• B. The capacity of a storage cabinet.
• C. A module of battery cells.
• D. An organization.

Answer: (A)

Ampere-Hour describes how much electrical charge a battery stores and can deliver over time. It’s a measure of charge capacity: if a battery provides 1 ampere for 1 hour, that is 1 Ah. So a 100 Ah battery could, in principle, supply 100 A for 1 hour, or 10 A for 10 hours, and so on. The rating is tied to a specific discharge condition, and real-world capacity can vary with how quickly you draw current. Remember that Ah tells you about charge, not energy—multiply Ah by the battery’s voltage to get watt-hours. The other options aren’t relevant to battery capacity.