How Long Does a Solar Battery Last?

Watch: How Long Does a Solar Battery Last? Warranty vs Lifespan

Many premium home batteries are supported by a manufacturer warranty of around 10 years. That does not mean the battery automatically stops working on the final day of year ten. It means the manufacturer provides defined warranty coverage for a stated period, subject to the warranty terms.

Warranty period and operating life

A warranty is a contractual promise. Battery life is the period during which the system continues operating at a useful level. The warranty may refer to time, energy throughput, charging cycles, retained capacity or a combination of these. Homeowners should read the product-specific document because not every 10-year warranty provides identical coverage.

Battery degradation

Rechargeable batteries gradually lose some storage capacity as they age. This is called degradation. A battery that originally provided a particular usable capacity may store less energy after years of operation. That does not necessarily make it unusable — it may simply provide less runtime than when new.

Factors affecting longevity

Battery life may be influenced by:

• cell chemistry and product quality;
• the number and depth of charging cycles;
• operating temperature;
• installation location;
• software and battery-management settings;
• household usage;
• correct commissioning; and
• compliance with manufacturer requirements.

What should a buyer compare?

Look beyond the headline warranty length. Compare:

• usable capacity;
• retained-capacity promise;
• cycle or throughput limits;
• product versus performance coverage;
• labour and transport exclusions;
• installer workmanship coverage;
• monitoring requirements; and
• the process for making a claim.

Solar Battery Group helps Australian homeowners compare the complete installed system, including the product, design, warranty conditions and expected household use.