Thanks Rod:
Rod is right on with his observations. I have had Battleborn lithium batteries for 2 1/2 years, and could not be happier. I float them at 13.4V, and never charge below freezing. I have a light which warns me when the batteries get down to 10% SOC.
The only thing I can add is that insurance problems is a "red herring". I recently had to change insurance companies because my previous company decided to withdraw from the market. Two brokers contacted a total of six companies, and only one said they would not insure a boat with lithium batteries.