Question of efficiency of converter charging Lithium battery

[DougO]

Curious if anyone has any data on the efficiency of charging a Lithium house battery with the onboard converter from shore power? Particularly of the power draw of the converter when the Lithium battery is fully charged? I ask because I am curious about the efficiency of charging the Lithium house battery with an external “solar generator & solar panels” to provide shore power to charge the house battery. I have tried this with a Scamp with AGM battery and that was quite inefficient, I think because you can always run power through a lead battery. When a Lithium battery is fully charged I think the power draw should be very low. Thanks.

[scubarx]

Lithium batteries don't particularly like to see a charge current when they are totally full. At home, under cover and plugged in, I turn the AC breaker to the charger off when the batteries are full. There are enough phantom draws to bring the batteries down to 50-60% in a week or so. At that time I turn the charger back on for an hour or so to get it back toward 100%.


When out in the sun the solar controller takes care of cutting the current to the batteries when full.