효율 손실을 고려하여 주어진 전류 소모량에서 배터리가 얼마나 지속될지 계산하세요. mAh, Wh, 암페어시(Ah) 간 변환도 가능합니다.
| 효율 | 사용 시간 | 사용된 와트시 |
|---|
용량을 와트시로 변환합니다: Wh = (mAh × V) / 1000. 부하를 와트로 변환합니다(W = V × A). 사용 시간(시간) = (Wh × 효율) / 부하 와트.
실제 사용 시간은 이론값보다 짧습니다. 배터리가 방전될수록 전압이 떨어지고, 저온에서는 용량이 줄어들며, 기기의 전류 소비도 완전히 일정하지 않기 때문입니다.
Everything is normalised to watt-hours before dividing. Capacity becomes Wh as mAh × V ÷ 1000, as Ah × V, or is used directly when you select Wh. The load becomes watts as mA × V ÷ 1000, as A × V, or straight through when you select W. Runtime in hours is then Wh × efficiency ÷ watts. The mAh readout is the reverse trip, Wh × 1000 ÷ V, which is why voltage matters even for a Wh entry.
Battery voltage (V) is the input people get wrong most often, and it silently rescales both conversions at once; the field's note offers Li-ion ≈ 3.7 V, AA ≈ 1.5 V and lead-acid ≈ 12 V. Efficiency (%) defaults to 85 and stands in for regulator and heat losses. The table beneath re-runs the identical calculation at 100, 90, 85, 75 and 60% so you can read the spread instead of trusting one assumption.
This is a constant-current, constant-voltage model and real batteries are neither. Voltage sags as a pack empties, so usable watt-hours fall short of the nameplate figure; cold weather cuts capacity further; and alkalines in particular surrender a large share of their rated mAh at anything above a gentle draw. The device presets are illustrative starting points rather than measured discharge profiles, so treat every result as an optimistic upper bound.
About 12 hours 45 minutes at the defaults. 3000 mAh at 3.7 V is 11.1 Wh, a 200 mA draw is 0.74 W, and the 85% efficiency setting leaves 9.4 Wh usable. Without that haircut the ideal figure would be 15 hours.
Multiply by the pack voltage, then divide by 1000. A 10000 mAh bank at 3.7 V holds 37 Wh. That is why airlines quote watt-hours rather than mAh, and why two packs with identical mAh at different voltages store different energy.
Around 80 to 85%. Boosting a 3.7 V cell up to 5 V costs real energy, which is why a 10000 mAh bank typically delivers nearer 6000–6500 mAh at 5 V. The 85% default is a fair starting point for most regulated devices.
The model assumes a steady draw at a steady voltage. Real packs sag as they empty, cold weather cuts usable capacity, and most devices spike well above their average load. Alkaline cells suffer worst, losing a large share of rated capacity at higher currents.
No. The second holds over three times the energy, 60 Wh against 18.5 Wh. Milliamp-hours only compare meaningfully at the same voltage, which is exactly why the calculator converts both capacity and load to watt-hours before dividing.
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