Basic Terminology 31 Parallel—A battery with parallel connections refers to cells that are connected in parallel (e.g., positive to positive, negative to negative, etc.). In a parallel connection, you are feeding current into all of the cells at the same time and pulling current out of them at the same time. When connecting cells in parallel, the system capacity is increased. The example below represents three cells: let us assume that they are 3.6 V and 5 Ah; in a parallel configuration, this would end up with still at 3.6 V but the capacity would increase to 15 Ah (5 Ah Ч 3 cells) ( Figure 6 ). Figure 6 Parallel cells.
Power Density—Measured in either kilowatt per kilogram (kW/kg) or kilowatt per Liter (kW/L). Similar to energy density, power density is the comparison of a battery’s power in relation to its weight or volume. Power Net—The term power net is a relatively new one. It is getting used largely in European countries by automakers to refer to the collection of on-board technologies and software that is being run electronically. It usually includes the infotainment systems, radio and communications systems, navigation systems, and anything else that is electri- cally powered. Primary Battery—A primary battery is simply a battery that is not rechargeable.
An example of a primary battery would be the AA-, C-, or D-type battery, which you might use in your household electronics that are often made using an alkaline chemistry. Resistance—Resistance is related to impedance and is a measurement of how much the materials within the cell slow down, or resist, the flow of current when a voltage is applied. It is measured in Ohms and is represented by the symbol Ω . DC resistance is