Yes, Lithium batteries are something else I'm looking at. I purchased a small on to run my back locator on to see how it performs and how I like it. If all goes well; I'll buy a big one for my trolling motor next year. (Need to get something lighter, Those lead batteries are getting heavier for this old man). My boat is mostly tied up to my pier and I have to carry my batteries up to my small yard barn to charge them.