Tons of lithium batteries out there. HOWEVER the big issue with them is charging rate and maximum voltage. When they get over charged they tend to combust. The problem with your set up is the alternator. You will note they all have a maximum rate and voltage for charging. If you go this way make sure you alternator does not exceed these numbers. The fires that involve lithium batteries are usually caused by over charging them, either rate or voltage. Having said that just follow manufactures direction and they work very very well. Will crank the engine over effortlessly as well. But don't follow their instructions make sure you have good insurance. I run a single Lithium ion battery in my TS car. Cranks the thing over way better than the two 16V AGM's it reaplced. And weighs 8lbs as it is in a conventional group 24 sized case.