Battery Life Calculator
Calculate how long your battery will last based on capacity and power consumption
Battery & Device Specifications
Battery Type Reference
| Type | Typical Voltage | Energy Density | Self-Discharge |
|---|---|---|---|
| Lithium-Ion | 3.6-3.7V | 150-250 Wh/kg | 1-2%/month |
| Lithium-Polymer | 3.7V | 130-200 Wh/kg | 2-3%/month |
| NiMH | 1.2V | 60-120 Wh/kg | 20-30%/month |
| NiCd | 1.2V | 40-60 Wh/kg | 10%/month |
| Lead Acid | 2.0V | 30-50 Wh/kg | 3-20%/month |
Battery Life Results
Enter your battery and device specifications, then click Calculate to see results.
Battery Discharge Visualization
Optimization Recommendations
Calculate battery life to see personalized recommendations.
How This Calculator Works
This calculator estimates battery life based on battery capacity and power consumption. The core formula used is:
Battery Life (hours) =
(Battery Capacity (mAh) × Battery Voltage (V) × Efficiency Factor × Depth of Discharge)
÷
(Device Power Consumption (W) × 1000)
For current-based calculations, the formula becomes:
Battery Life (hours) =
(Battery Capacity (mAh) × Efficiency Factor × Depth of Discharge)
÷
(Current Consumption (mA) × Number of Devices)
Several factors affect battery life calculation:
- Battery Chemistry: Different battery types have different discharge characteristics.
- Temperature: Most batteries perform optimally at room temperature (20-25°C). Performance decreases at higher or lower temperatures.
- Discharge Rate: Batteries typically provide less total energy when discharged at high rates.
- Efficiency Factor: Accounts for energy losses in voltage regulators, converters, and wiring.
- Self-Discharge: Batteries lose charge over time even when not in use.
For maximum accuracy, refer to the specific battery's datasheet, as actual performance may vary based on manufacturing quality, age, and usage patterns.
This calculator provides estimates only. Always add a safety margin when designing battery-powered systems for critical applications.