Proper maintenance of solar energy storage systems ensures optimal performance and extends equipment lifespan. This guide explores practical strategies for residential and commercial users while addressing industry trends and common challenges. This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www. National Renewable Energy Laboratory, Sandia National Laboratory, SunSpec Alliance, and the SunShot National Laboratory Multiyear Partnership (SuNLaMP) PV O&M Best Practices. NFPA 70E requires that electrical equipment be properly maintained, and following NFPA 70B is an excellent way to comply. Solar energy storage devices – whether lithium-ion. The article outlines maintenance procedures for photovoltaic systems, including inverters, charge controllers, PV arrays, and battery banks.