OK new member
Early 2015 diesel extracab tray
I have a slide on camper with a portable AGM battery, redarc bcdc charger and solar panel in/on the camper. Redarc as it fitted in the battery box.
I have just installed a second battery deep cycle flooded in a ARB bracket under bonnet being charged via a Redarc isolater solenoid with a switched 10mm, 35mm2 jump start cable, as a Quick installation before a trip, while I work out a BCDC charger. THis goes to an in cabin fridge, and various electronics charging. Unsure if this needs a voltage boosting diode, Have a cigarette socket voltmeter in car and house sockets to check on this trip. Probably should monitor engine bay temperature at battery position.
I have just read the 49 pages of this thread, then a century battery spec sheet, as that was the battery ARB and battery world recommended and could supply and fitted, then onto a page that lists charging and gassing voltages at various temperatures for lead acid batteries.
https://www.powerstream.com/SLA.htmAs temperatures rise to common under bonnet temperatures the gassing voltage can be below the charging voltage. This would be what the temperature compensating alternator is trying to allow for. Could this be what is happening with BCDC chargers when there is boilover? That the BCDC is charging to a fixed voltage and backs off the current at higher temperatures , rather than cutting the the voltage.
Also if the BCDC charger is located out of the heat such as in front of the radiator on the redarc bracket, then the unit will not sense the battery heat back in the far corner of the engine bay, so output reduction at high temperatures may not happen, and boilover may be worse.
I am no expert but am puzzling over the best way forward.
Will see if Redarc have any further information next year.