42: L42 - Best Location for Lithium Batteries

[Jim Woodall]

Has anyone investigated replacing the L42 batteries with Lithium? If so, any idea of typical ambient operating temperatures in the engine compartments, particularly in the starboard engine compartment? I've not done very much research but with the house batteries and chargers in the starboard engine compartment an upgrade to Lithium might necessitate moving the batteries and chargers to a cooler location. My understanding is that ambient temperature at or above 45C (113F) is very detrimental to the charging cycle and life of the batteries. I think the engine compartments are well ventilated, but I'm curious if they're well ventilated enough to drop the ambient temperature below 45C (113F). Obviously a few degrees below that threshold would be better.

I've seen recent posts from Impi and Starry Horizons (Out Chasing Stars) about this issue. Starry Horizons' battery bank (and chargers I think) were moved from the engine compartment to a location under a settee in the saloon.

Note sure how accurate this next bit is, but I read that getting the ambient temperature down below 105F puts one in a range in which the charging cycle and battery life will not suffer at all. I'm not sure if it's realistic to get enough ventilation in the L42 starboard engine compartment to even approach 105F.