Battery capacity, expressed in kilowatt-hours (kWh), quantifies the electrical energy a battery can store and deliver over time.
It represents the amount of energy consumed when a device with a power of one kilowatt operates for one hour. In the realm of electric mobility, kWh is used to assess a vehicle’s potential range: a higher capacity translates to more kilometers the vehicle can travel before requiring a recharge.
For instance, a heavy-duty vehicle consuming 1.2 kWh/km could travel approximately 500 km with a 600 kWh battery. It’s crucial to differentiate between gross capacity (total storable energy) and usable capacity (energy actually available for driving), which is generally lower to preserve battery life and avoid extreme charge/discharge cycles.
Note: kWh measures a quantity of energy, whereas kW expresses instantaneous power, distinguishing the battery’s storage capability (kWh) from its charging speed (kW).