Battery
Battery Life Calculator
How long a battery lasts from its capacity and the load current, with a usable-capacity allowance.
Runtime = capacity × usable fraction ÷ lo…
Also called battery runtime · how long will battery last
Energy & Environment · 9 calculators
Battery Calculators
Battery life and runtime, capacity, charging time, C-rate, watt-hours and amp-hours, series and parallel packs.
Battery
Battery Capacity Calculator
Battery bank capacity in Ah and kWh for a required runtime, allowing for depth of discharge.
Ah = load W × hours ÷ efficiency ÷ DoD ÷ …
Also called battery bank size · ah calculator
Battery
Battery Charging Time Calculator
How long a battery takes to charge from its capacity, charger current and state of charge.
time = Ah to add ÷ charger current ÷ effi…
Also called charge time calculator · how long to charge battery
Battery
C-Rate Calculator
Battery C-rate from current and capacity, with the charge or discharge time it implies.
C-rate = current ÷ capacity in Ah
Also called c rating battery · discharge rate calculator
Battery
Watt Hours Calculator
Convert battery amp-hours and voltage into watt-hours, and back again.
Wh = Ah × V
Also called ah to wh · wh to ah
Battery
Amp Hours Calculator
Amp-hours from current and runtime, or the runtime a given capacity gives.
Ah = current × hours ÷ usable fraction
Also called ah calculator · battery amp hours
Battery
Batteries in Series Calculator
Voltage and capacity of a battery string wired in series.
V_total = n × V_each
Also called series battery voltage · batteries in series
Battery
Batteries in Parallel Calculator
Capacity and energy of batteries wired in parallel, with the total current available.
Ah_total = n × Ah_each
Also called parallel battery capacity · batteries in parallel
Battery
Battery Backup Calculator
Battery capacity needed to back up your home for a set number of hours.
kWh = load × hours ÷ efficiency ÷ depth o…
Also called home battery size · backup power calculator
Key battery formulas
| Battery Life | Runtime = capacity × usable fraction ÷ load current |
|---|---|
| Battery Capacity | Ah = load W × hours ÷ efficiency ÷ DoD ÷ system V |
| Battery Charging Time | time = Ah to add ÷ charger current ÷ efficiency |
| C-Rate | C-rate = current ÷ capacity in Ah |
| Watt Hours | Wh = Ah × V |
| Amp Hours | Ah = current × hours ÷ usable fraction |
| Batteries in Series | V_total = n × V_each · Ah unchanged |
| Batteries in Parallel | Ah_total = n × Ah_each · voltage unchanged |
| Battery Backup | kWh = load × hours ÷ efficiency ÷ depth of discharge |