I checked into the lithium battery at the local battery warehouse and there were two factors.. One was an old style charging system might not charge it correctly, a modern computer/ECM system with a temperature sensor is highly recommended with that style battery... Secondly I was told they don't like any high temp environment and battery life suffers{including the case swelling}... They could have sold me one and I wouldn't have known the difference I was only looking at the weight savings without really researching... At least they were honest about it...