Here's the latest from Jackline policy representative on Lithium.
"Markel's underwriters are not currently receptive to insuring boats with Lithium batteries. If we learn of lithium installations on boats they already insure, we must bring that to their attention for review which could result in a cancellation. They are very sensitive to the exposures they have of both physical damage losses and the even larger potential for resulting liabilities should a failure occur to a lithium set up. They recently started to consider coverage for some lower valued vessels using LifePO4 batteries with a BMS by a US manufacturer, if professionally installed in the states. However, Kristy’s hull value is higher than that current threshold. Unfortunately, Markel is not going to consider any changes to their position until 2022 at the earliest. It is my hope that they will become more flexible on the matter since many cruisers are looking to make the upgrade.
If you wish to move forward with the upgrade, we will need to seek quotes from an alternate carriers."
Kent & Iris