Estimate runtime, required capacity, or maximum current for battery-powered devices.
Enter values to see results
| Chemistry | Nominal V | Max DoD | Self-Discharge | Notes |
|---|---|---|---|---|
| Li-ion / LiPo | 3.7V | 80-90% | 2-3%/month | Most IoT applications |
| LiFePO4 | 3.2V | 80% | 1-2%/month | Long cycle life |
| Alkaline | 1.5V | 90% | 2-3%/year | Primary (non-rechargeable) |
| NiMH | 1.2V | 90% | 15-20%/month | High self-discharge |
| Lead Acid | 2V/cell | 50% | 3-5%/month | Deep cycle rated |
| CR2032 (Lithium) | 3V | 90% | 1%/year | Coin cell, very low self-discharge |
Battery runtime depends on capacity, average current draw, and efficiency factors. For devices with multiple power modes, the duty cycle of each mode determines the average current consumption.
A 2000mAh battery at 100mA gives 20 hours. But real-world factors reduce this.
If a device uses 50mA for 10% of the time and 10µA for 90%, average = 5.009mA.
Modern MCUs can drop to µA levels in sleep. Wake only when needed using interrupts or timers.
Radio transmission is the biggest power consumer. Batch data, use compression, and minimize TX power.
Run at the minimum clock speed needed. Many MCUs scale power linearly with frequency.
Use MOSFETs to completely disconnect unused peripherals like sensors, LEDs, or communication modules.
Switching regulators are more efficient than linear regulators, especially with large voltage drops.
Datasheet values are typical. Use a current meter or power profiler to measure actual consumption.