Estimate charging time from battery capacity, state of charge and charger current.
Charging is efficient and fast up to about 80 per cent state of charge, after which the charger tapers current to avoid overvoltage. The last 20 per cent therefore takes disproportionately longer than the bulk phase. Quoting a full-charge time is misleading for most chemistries; the bulk phase to 80 per cent is the figure that matters in practice.
Battery Charging Time
Time = capacity × ΔSoC ÷ (charge current × efficiency)
Time = capacity × ΔSoC ÷ (charge current × efficiency) Charging is efficient and fast up to about 80 per cent state of charge, after which the charger tapers current to avoid overvoltage. The last 20 per cent therefore takes disproportionately longer than the bulk phase.
Quoting a full-charge time is misleading for most chemistries; the bulk phase to 80 per cent is the figure that matters in practice.
This calculator takes 5 inputs: Battery capacity, Starting state of charge, Target state of charge, Charger current, Charging efficiency. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.