Solar Technology
Solar Battery Storage Explained
Batteries let you use solar energy after sunset and during power cuts. Compare lithium and lead-acid options and understand capacity, depth of discharge and lifespan.
1 min read
Solar panels only produce electricity during daylight. Batteries store surplus energy so it can be used in the evening, at night or during a power outage.
Common battery types
- Lithium iron phosphate (LiFePO4): long cycle life, deep usable capacity, low maintenance and good thermal stability. Higher upfront cost but often better value over time.
- Lead-acid (flooded, AGM, gel): lower upfront cost and widely available, but shorter life and lower usable depth of discharge. Flooded types need regular maintenance.
Key terms
- Capacity (kWh or Ah): how much energy the battery can store.
- Depth of discharge (DoD): how much of the capacity can be used regularly without shortening battery life.
- Cycle life: how many charge and discharge cycles the battery is rated for.
- Battery management system (BMS): electronics that protect lithium batteries.
Sizing storage
Start by listing the loads you want to run from the battery and for how long. Multiply each load's power by its hours of use to estimate the energy required, then allow for the battery's usable depth of discharge and system losses.
