Lithium batteries are a great choice for solar power systems. They are especially forgiving when it comes to the level of discharge they will tolerate. Said another way, you can safely go up to a 100% depth of discharge (DoD) while maintaining nearly 98% efficiency. Many of the lithium deep cycle batteries we offer have a cycle life north of 10,000 cycles (at 80% DoD)! Lithium batteries work well in solar systems with battery backup because they can be charged up and do not require maintenance.