Lithium batteries are the most recent technology for batteries. They are more advanced and so they are usually more expensive than regular flooded or gel batteries. Lithium ion batteries are usually compact compared to their lead acid equivalent. And they run over 4000 cycles with 80 percent debt of discharge. This means longer life span and longer warranty period. Smksolar 5kwh 48v lithium battery is sold with 5 years warranty period and up to 15 years working life span.