Watt (Watt, symbolized as W) is the standard unit of power in the International System of Units, representing the rate of energy transfer or conversion per unit of time.
Watt represents the power output or absorption capability that a battery can provide at a single moment. It is particularly crucial in the following scenarios:
Measuring output power
For example, an electric vehicle battery has a maximum output of 150 kW, which means it can provide 150,000 W of power instantaneously during acceleration.
Energy storage systems (such as ESS) may need to output or absorb hundreds of kilowatts or even megawatts of power to support grid balance.
Differentiating ‘power’ and ‘energy’
Power (watt) measures the speed – ‘how fast energy conversion occurs’;
Energy (watt-hour) measures the total amount – ‘how long the battery can run’.
