The batteries we install are built for long-term reliability. You can expect a long and productive lifespan from a quality system.
Warranty and lifespan:
- Manufacturer warranty — most premium batteries come with a minimum 10-year warranty. Tesla Powerwall, for example, has a 10-year warranty.
- Expected lifespan — 15–20+ years in typical domestic use
- Capacity retention — lithium-ion batteries gradually lose a small amount of capacity over time. A good battery retains around 70–80% of its original capacity after 10 years
What affects battery lifespan:
- Cycle count — each charge and discharge is one cycle. Most batteries are rated for 4,000–6,000 cycles. One cycle per day gives you 10–15+ years.
- Depth of discharge — regularly draining the battery to 0% wears it faster than cycling between 20–80%. Modern battery management systems handle this automatically.
- Temperature — batteries perform best in moderate temperatures. Indoor installation (garage, utility room) is ideal in Scotland.
After the warranty period:
The battery does not stop working when the warranty expires. It will still function, just with slightly reduced capacity. Even at 70% capacity, a 10 kWh battery still provides 7 kWh of usable storage.
