Swapped out my old AGM setup for a pair of Fogstar Drift 100Ah lithiums last spring and honestly thought I'd cracked it — proper smug about it for about three weeks.
Then my Victron SmartSolar started throwing low voltage warnings every other Tuesday like clockwork, despite 200W of panels on the roof and barely running anything heavier than a 12V compressor fridge and a few USB chargers.
Turns out my cable runs were undersized for the new discharge rates — lost nearly 0.8V just between the battery and the BMV-712. Sorted it now but feel like a proper muppet. Anyone else fall into the "upgraded the batteries, forgot everything else needs upgrading too" trap?
