@CharlieStevens85 had this exact headache with my Multiplus II and a bank of Fogstar Drift cells. Once @PennineNomad's tail current fix is sorted, check your absorption voltage too — if it's set...
@ShortCircuit 200Ah for a garden office through a British winter was always going to be marginal at best.
VitoProject | Posts: 1,156
@Rob1963 that "enthusiastically redistribute" comment made me laugh despite myself — seen similar.
@BitsAndBobs that's the bit nobody talks about — battery performance in winter is directly tied to ambient temp, not just the cells themselves.
@Davo49 the EV charging overnight is where it all falls apart isn't it. Even with decent panels you're basically running blind once the sun drops — you're drawing from whatever's left in the bank...
VitoProject | 1,203 posts
@Russ1992 The flat voltage curve issue @Lefty72 mentioned is exactly why SOC estimation from voltage alone is basically useless with LiFePO4 below about 10°C.
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2 months ago
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VitoProject | Posts: 1,203
Yeah the high voltage thing is well documented with Victron kit in winter — @BigAl's almost certainly right.
Finally got my EV charging setup running off the battery bank but the Multiplus-II 5000VA keeps throwing an overload fault when the EVSE ramps up past about 3.5kW.
@OllieThompson73 the Fogstar Drifts have a built-in BMS already — that's literally the point of buying them over bare cells.
Both MPPTs are making their float decision independently based on absorb voltage threshold being hit — not based on actual capacity restored.
Typical forum doing that. @MultiPlus_Queen just edit your original post and paste the full thing again — usually works when the initial submission gets mangled.
When you do repost, include:
Panel...
@CopperSparky for what it's worth I've got a Victron Orion-Tr Smart 12/12-30 between my starter battery and LiFePO4 bank — non-isolated version. Does the job without fuss.
I'd be keen to know the exact lithium chemistry and cell manufacturer — LiFePO4 specs vary quite a bit. What's the BMS firmware version on the Victron stack?
Had similar grief with my battery setup. Insurance firms seem to operate from a 1995 rulebook. Worth asking your broker if they can reclassify it as "domestic energy storage" rather than...
