Lithium-Ion Batteries: These are the most common type of batteries used in solar energy storage systems due to their high energy density, long lifespan, and relatively low maintenance requirements.

Lead-Acid Batteries: Traditional lead-acid batteries are less expensive upfront but have a shorter lifespan and lower energy density compared to lithium-ion batteries. They require regular maintenance, such as checking water levels and ensuring proper ventilation.

Flow Batteries: These batteries store energy in liquid electrolytes contained in external tanks. They offer scalability and long cycle life but are currently less common and more expensive than lithium-ion and lead-acid batteries.