Anyone else running a Victron Multiplus with Fogstar Drift lithium — what BMS settings are you using?

Just wired up a 200Ah Fogstar Drift 12V to my Multiplus-II 12/3000 and trying to nail down the charge profile. Fogstar recommends 14.2V absorption but I've seen people pushing to 14.4V without issue. Running DVCC through a Cerbo GX so in theory the BMS should be taking over, but I want a sensible fallback in VEConfigure just in case.

Main thing I'm unsure about is absorption time. I've got it set to 1 hour at the moment which feels conservative. Float is at 13.5V. No cell issues so far across about 20 cycles but still feels like I'm guessing a bit.

Anyone dialled this in properly? Especially curious if you're using the BMS CANBUS connection or just relying on the Victron's own charge algo.

Hey @OllieThompson73, I'm running almost the exact same setup. I settled on 14.2V absorption after chatting with Fogstar support directly — they were pretty clear that 14.4V is technically within tolerance but offers negligible capacity gain whilst adding unnecessary cycle stress over time.

One thing worth mentioning that I haven't seen covered yet: make sure your float is set no higher than 13.5V. I had mine at 13.8V initially and the BMS was kicking out intermittently. Dropped it to 13.5V and it's been rock solid since.

Also set your absorption time fairly short — I'm running 20 minutes rather than the default adaptive setting. The Drift cells genuinely don't need lengthy absorption like AGM does. Worth configuring in VictronConnect rather than fiddling with the rotary switch if you haven't already.

Stick with 14.2V — Fogstar's recommendation exists for a reason and the warranty conversation gets awkward if you've been pushing higher.

On the Multiplus-II side, the setting that catches people out is absorption time. With lithium you want this very short (I run adaptive absorption off entirely and use a fixed time of around 20 mins). Default lead-acid style long absorption will just cook the top of your cells repeatedly.

Also worth checking your tail current setting in VEConfig — set it to around 2-4% of capacity (so ~4-8A on a 200Ah bank) to end absorption early once charge current drops. That's doing the real work of protecting your cells, not the voltage figure people obsess over.

Running this on my narrowboat with a 400Ah Drift bank and it's been solid for 18 months.

Hey @OllieThompson73 — worth mentioning that alongside your absorption voltage, the absorption time and tail current settings matter just as much with LiFePO4. On my Multiplus I've got the absorption time cut right down to around 1 hour max, and more importantly I'm using the tail current (under the battery settings in VE.Configure) to end absorption early once current drops to around 2-3% of capacity — so roughly 4-6A on a 200Ah pack. That way you're not sitting at elevated voltage longer than necessary. Also make sure float is set to 13.5V so it's not constantly pushing the cells. @CraigDavies is right to stick with Fogstar's 14.2V recommendation — no real gains worth chasing at 14.4V on this chemistry.

Hey @OllieThompson73, great setup! One thing worth adding to what @CraigDavies and @ShedGenius have mentioned — make sure your float voltage is set conservatively too. I run mine at 13.5V which keeps the cells happy without constantly topping them off. Also worth enabling the repeated absorption setting in VE.Configure and setting it to every 7 days or so, rather than letting it sit in float indefinitely.

Are you using a VE.Bus Smart Dongle or direct BMS comms? If your BMS supports DVCC through a Cerbo/Venus device, letting the BMS control charge parameters directly takes a lot of the guesswork out of it entirely. That's probably the cleanest solution long-term with Fogstar's own BMS.