The rechargeable batteries used in solar-powered lights last around 5 to 15 years and the lifespan of these batteries is determined by their use cycles. With growing energy storage solutions, solar batteries are expected to have a better lifespan in the future. Lifespan of solar batteries mostly depends on the following factors:
Type of batteries:
Lead acid batteries come with a lifespan of around 3 to 5 years. The estimated life of lithium ion batteries is about 2 to 3 years. LiFePO4 batteries have a lifespan of approximately 5 to 6 years.
Battery usage:
The life expectancy of a solar battery can be determined by its cyclic life or usage cycles. While a flooded lead acid battery can provide 300 to 700 cycles, lithium batteries are expected to give around 2000 cycles.
Battery temperature:
When stored in a high temperature setting, the capacity of a battery tends to increase; however, when kept under high temperatures, the life cycle of the battery starts to decrease gradually as the chemical reactions in a battery are found to be higher when stored in high temperatures.
Depth of discharge:
When a battery is charged on a daily basis, it starts to degrade slowly and loses its capacity to store energy. Depth of discharge of a battery simply means the amount of a battery’s capacity that has been used. LiFePO4 batteries have a higher DoD of around 80% which means more of the battery capacity can be utilized.
Can we improve lifespan of solar batteries?
- Purchase your solar lights from a reputed dealer. A good quality battery usually comes with good manufacturer guarantee.
- Installing the battery in a climate-controlled location helps in increasing the life cycle of the battery.
- Ensure you do not leave your solar batteries idle for too long as they are likely to be damaged when uncharged for a very long time.
- It is important to choose the right type of solar battery
Modern solar street lights generally use lithium ion or LiFePO4 batteries and the fact that they recharge faster can directly influence the total life of the entire solar street light unit. Moreover, lithium batteries are more recommended because they have a longer lifespan and can be easily replaced if they are not working properly and they do not require any maintenance during their operating life.