Battery Presets
Capacity (Ah)
100
1.2 kWh × 1000 ÷ 12V
Formula: Ah = kWh × 1000 ÷ Voltage
Understanding kWh vs Ah
Kilowatt Hours (kWh) measures total energy storage - it's the universal unit for comparing batteries regardless of voltage. Amp Hours (Ah) measures charge capacity at a specific voltage, which is useful for sizing wiring and charge controllers.
When to Use Each Unit
- Use kWh to compare batteries of different voltages or estimate how long your loads can run
- Use Ah to size battery cables, fuses, and charge controllers for your specific voltage system
Common Battery System Voltages
- 12V systems - RVs, boats, small off-grid setups (higher current)
- 24V systems - Larger RVs, medium solar systems
- 48V systems - Home battery backup, large solar (lower current, thinner wires)
Depth of Discharge (DoD)
DoD determines how much of your battery capacity you can safely use:
- Lead-acid batteries - 50% DoD recommended to maximize lifespan
- LiFePO4 batteries - 80-90% DoD with minimal impact on cycle life
Related Calculators
