Switch to Lithium Iron Phosphate Batteries. The chemistry does not supply it's own oxidizer like the Lithium Ion batteries in you laptops, so it's much safer from a fire hazard point of view. Yes they cost more up front, but they last longer so in the long run they end up costing less. I'm still running the original K2 batteries that were the subject of my battery article in Soaring sever years ago. They still work fine, no battery issues since the switch. The electronics, and especially the radio like the fact that the voltage never drops below 12V, after 5 hours in the air with a full panel of electronic gizmos.

SF