Batteries and DC Power Supplies EGR 101 1 Batteries EGR 101 2 Battery Capacity – a measure of how long the battery will last at a given output current, measured in ampere-hours (Ah) Example: If a battery has 1 Ah rating, then, -1 A discharge rate: battery will last 1 hour -100 mA discharge rate: battery will last 10 hours - 4 A discharge rate: battery will last 15 minutes EGR 101 3 Series – Connected Batteries EGR 101 4 Parallel – Connected Batteries EGR 101 5 Types of Batteries (Primary Cells) – cannot be recharged Carbon-zinc Alkaline Silver-oxide Zinc-air Lithium Common Batteries (Secondary Cell) – can be recharged Lead-acid Nickel-Cadmium (Ni-Cd) Nickel Metal Hydride and Lithium Ion – newer replacements for Ni-Cds EGR 101 6 DC Power Supplies DC Power Supply a piece of equipment with dc outputs that can be adjusted to provide any voltage within its supply limits EGR 101 7 DC Output Voltages EGR 101 8