Gross and Net Battery Capacity
Gross battery capacity is the battery's declared total energy content before the normal driver-accessible operating window is applied. Net capacity, often called usable capacity, is the energy the vehicle permits for driving under defined conditions.
How the figures relate
Manufacturers and test organisations do not always use gross, nominal, net, usable, and available in exactly the same way. A useful comparison therefore requires the source's definition and test boundaries, not only a number in kilowatt-hours.
The declared difference is:
Gross-to-net difference = gross capacity - net capacity
That difference reflects energy outside the stated usable window, but it does not reveal how the margin is divided above and below the operating range. It also does not show whether the vehicle can continue driving after the dashboard reaches 0%.
EVKX defines net capacity as all driver-accessible energy from displayed 100% until propulsion stops. If a vehicle has an accessible reserve below displayed 0%, that energy is included in EVKX net capacity and can be recorded separately as a usable buffer.
The complete relationship between gross capacity, displayed 100-0% energy, below-zero reserve, and inaccessible margins is explained in Battery Buffer and Usable Capacity.
What the numbers do not prove
A larger gross-to-net difference does not by itself prove better durability, greater safety, or a longer warranty. Battery chemistry, cell limits, temperature, balance, software, ageing targets, and the manufacturer's rating method all influence the chosen operating window.
Do not estimate an unknown net capacity by subtracting a typical percentage from gross capacity. Buffer strategies vary by battery and vehicle. Gross and net figures also describe rated energy under specified conditions; they are not a direct measurement of the present health of a used battery.
Capacity is normally expressed in Kilowatt-Hour (kWh).