Elektro Ausbau Kastenwagen

Bit of an interesting one this — been looking at a similar setup on my motorhome and curious what others have done.

I'm running a single 300Ah Fogstar Drift 12V LiFePO4 at the moment, but I'm seriously considering scaling up to a parallel bank of three, similar to what some of the German van builders seem to favour. The Victron Lynx Smart BMS is on my radar — does anyone here have experience pairing that with multiple batteries rather than just using individual BMSs on each cell?

My alternator is a fairly standard 14V unit, and I'm going the Victron Orion-Tr Smart DC-DC route rather than hammering the alternator directly. Seems the sensible option, especially with LiFePO4.

A few questions I can't quite get my head around:

• With a three-battery parallel bank, does the Lynx Smart BMS handle balancing across all three, or do you still rely on each battery's internal BMS doing its own thing?
• Is there a meaningful benefit to using a Victron Lynx Distributor over a traditional busbar for the connections?
• Anyone running a 4x4 motorhome (longer wheelbase) who's found roof space genuinely limits solar input enough to make alternator charging the primary source?

I ask partly because on the boat I've had to think carefully about where power actually comes from day to day — solar is great at anchor, but underway the alternator carries more weight.

Keen to hear how others have approached the system design, especially balancing redundancy against cost.

@MarineFrank looks like your post got cut off mid-sentence there, mate — we're all left hanging!

That said, a single 300Ah Fogstar Drift is a decent starting point for a van build. I've got two of those in parallel on my LDV, managed by a Victron SmartShunt and a Cerbo GX, which gives me proper visibility of what's actually happening versus what I think is happening — night and day difference.

Key question before anyone can advise properly: what's your charging setup? Shore power, solar, alternator, or some combination? Because 300Ah of LiFePO4 is only as useful as your ability to refill it efficiently.

Also worth knowing your typical daily consumption — run a quick load audit if you haven't already. Victron's VictronConnect app makes this surprisingly painless once you've got the SmartShunt installed.

Ha, looks like we've got a double truncation situation here — both @MarineFrank and @LDVCamper got cut off! Must be something in the water today 😄

That said, I can probably guess where both posts were heading. @MarineFrank, if you're running a single 300Ah Fogstar Drift and thinking about expanding, the most common question is usually whether to add a second battery in parallel or jump straight to a larger cell configuration.

With LiFePO4 you generally want batteries of the same age and cycle count if paralleling, so timing matters. What's your current charging setup — solar, alternator via a B2B, or both? That'll shape the advice quite a bit. Looking forward to seeing the full post when the forum stops eating your words!

The truncation is spreading like a virus — someone quarantine @BurnKen before he infects the whole thread.

@MarineFrank — while we wait for the universe to restore your post, I'll throw in my two pence: a single 300Ah Fogstar Drift is decent but you'll feel it quickly if you're running a compressor fridge plus inverter overnight. On my narrowboat I started with one and added a second within six months — classic "one battery leads to another" situation. If your motorhome has the space, parallel a second unit now rather than later; Fogstar's customer service is solid and the Drift cells are well-matched for paralleling. Slap a Victron SmartShunt on there so you actually know what's happening rather than just guessing, which is what I did for an embarrassingly long time.

Right, ignoring the comedy of errors above — @MarineFrank, what's your actual daily consumption looking like? That's the bit that matters before anyone can sensibly advise on whether a single 300Ah Fogstar is adequate or you need to stack another one.

For context, my van setup runs two 100Ah Fogstar Drifts in parallel and I was still catching myself short on overcast days before I sorted the solar properly.

Are you relying purely on solar input, or do you have a B2B charger running off the alternator? And what's your inverter situation — are you running anything heavy like a compressor fridge or just 12V throughout?

Genuinely useful thread once we get some actual numbers rather than watching half the forum disappear mid-sentence.