The power output of a battery per unit volume, usually expressed in W dmâ€“3 and quoted at 80 per cent depth of discharge.

Power density is the ratio of a fuel cell's power output to its weight. Power density is more important in non-stationary applications like fuel cell cars, portable power supplies, and NASA missions.

the rate or amount of radiofrequency or electromagnetic energy flowing through a given area. It is measured in watts per square meter.

The ratio of the power available from a battery to its weight (W/kg) or volume (W/L). Also used on a weight basis (W/Kg).

Performance of a fuel cell stack, related either to the volume (kW per liter) or to the weight (kW per kilogram).

fluence/pulse width ( units in W/cm2).

A batteries rated power per unit volume. Measured in units of watts per liter (w/l).

The amount of radiant energy concentrated at a point.

The power density of an individual fuel cell is the power produced related to the active area or volume of the cell.

The power per unit cross sectional area in an electromagnetic field. Unit watt per square metre, symbol W m-2.

The energy flowing from an antenna through a unit area normal to the direction of propagation in a unit time. Measured in watts per square metre.

Laser output per unit area, such as watts per square centimeter (W/cm2).

The amount of power per unit area of a free windstream.

Power density is the ratio of the power available from a battery to its volume (watt/liter). Specific power generally refers to the ratio of power to mass (watt/kg). Comparison of power to cell mass is more common.

In an electromagnetic wave, the rate of power flow in a specific direction at a particular point in a transmission medium, expressed as energy per unit time (power, or radiant flux) per unit cross-sectional area normal to the direction of propagation. The power density generally diminishes with increasing distance from the source as a result of absorption, reflection, scattering, and possibly other effects, as well as geometric spreading of the beam. For surfaces or objects that intercept the radiation at a sufficiently long distance from the source, the propagating energy may be regarded as plane-wave or parallel-beam radiation. Then the power density is the same as the irradiance at a surface normal to the beam.