The lifespan of a solar panel battery can vary depending on the type of battery and how it is used and maintained. Generally, solar panel batteries have an estimated lifespan of 5 to 15 years.

Lithium-ion batteries, such as lithium iron phosphate (LiFePO4) batteries, are becoming increasingly popular due to their longer lifespan and better performance compared to other battery types. These batteries can typically last 10 to 15 years, depending on the quality and usage.