People weigh the investment in solar energy systems with a lifespan of only 5-6 years. But that is completely wrong. The minimum lifespan of the Li-ion battery itself is 10 years. The life expectancy of the whole solar energy system is 25-30 years. Even after that, it is not that the system will stop working. It is predicted that the optimum performance might decrease after that time. But the solar energy system will function even after that. Solar panels and systems can work for decades, given that they are cleaned and maintained regularly.