⚡ Battery Pack Calculator
🔋 REQUIRED PACK ENERGY
-- kWh
🔢 TOTAL CELLS NEEDED
-- cells
🌡️ MAX THERMAL LOAD (Heat)
-- W
Capacity, cell count & heat load estimation
Battery pack sizing for an electric vehicle starts with the energy requirement: E = Range × Consumption. A typical electric two-wheeler consumes 15–25 Wh/km, while a car consumes 150–250 Wh/km depending on weight and aerodynamics.
The usable capacity is always less than the rated capacity. Lithium-ion packs are typically discharged between 20% and 90% SOC (State of Charge) to preserve cycle life. So a 10 kWh pack has about 7 kWh usable energy in practice.
Pack voltage is determined by the number of cells in series. A 48V pack uses 13S (13 cells in series at 3.7V nominal). Higher voltage reduces current for the same power, which reduces cable size and heat losses — that is why commercial EVs use 400V or 800V systems.
| Chemistry | Nominal V | Energy Density | Best For |
|---|---|---|---|
| NMC | 3.6V | 150–220 Wh/kg | Passenger EVs |
| LFP | 3.2V | 90–160 Wh/kg | Commercial, stationary |
| NCA | 3.6V | 200–260 Wh/kg | Performance EVs |
| LTO | 2.4V | 50–80 Wh/kg | Fast charging, long life |
Design tip: Always add 10–15% to your calculated pack capacity for degradation over the battery's life. A pack that is perfectly sized on day 1 will fall short of range requirements after 2–3 years of use.