Recommendation for a 48V->12V LiFePO4 battery charger?

Running a 48V bank in the shepherd's hut with a separate 12V LiFePO4 for lighting and the radio, so I've wrestled with exactly this.

Ended up going with a Victron Orion-Tr Smart 48/12-30A and honestly it's been rock solid. The DC-DC isolated converter topology means your 12V battery is properly isolated from the 48V bank — no nasty ground loops, and the BMS on each battery stays happy. You can dial in absorption and float voltages to match your LiFePO4 chemistry precisely, which matters more than people realise.

The Bluetooth monitoring through VictronConnect is genuinely useful rather than just a gimmick — I caught a dodgy connection once because the efficiency figures looked wrong.

A few things worth considering:

• Isolated vs non-isolated — if your 48V and 12V systems share any ground reference, non-isolated can cause grief
• Current rating — the 30A version charges a modest 12V bank quickly enough without hammering your 48V system during low-production periods
• Victron ecosystem — if you're already running Cerbo GX or similar, the Orion integrates beautifully

The main alternative people mention is the Sterling Power B2B range, which has a good reputation particularly for vehicle installs, though I haven't personally used one at 48V.

What's your 12V battery capacity and what loads are you running off it? That'll probably determine whether 30A is sufficient or whether you'd want the bigger unit.

@MPPTGal the Orion-Tr Smart is absolutely the "you can't go wrong but you can go broke" option of the DC-DC charger world 😄

Worth noting it does isolated vs non-isolated versions — if your 48V and 12V banks share a negative you'll want the non-isolated one, otherwise you're just buying yourself a spectacular ground loop for Christmas.

Also pairs beautifully with VictronConnect so you can obsess over charge curves at 2am like the rest of us.

If budget's tight, Renogy do a 48V→12V DC-DC that's considerably cheaper, though I wouldn't trust it to remember my birthday the way Victron does.

@VoltBarry not wrong on the price, mine nearly gave me a heart attack at checkout — but it's been sat in my static caravan doing its job without a single moan for three years, which is more than I can say for most of the cheap Chinese alternatives I tried first that turned my 12V bank into a very expensive hand warmer.

Got one in my shepherd's hut doing exactly this job — 48V bank down to a 12V LiFePO4 for the usual 12V stuff. The Bluetooth monitoring alone is worth a chunk of the premium for me, can see exactly what's going on without crawling into the cupboard.

That said if budget's tight, worth looking at the non-Smart Orion-Tr — same converter, no Bluetooth. Saved me about £40 on the one in my static caravan where I don't need the app faff.

Just make sure you've got the isolated version if your 48V and 12V banks share any common grounding — caught me out first time round.

@Ben1968 the Bluetooth monitoring is what sold me too when I was researching this for my boat setup. Quick question though — did any of you need to configure the absorption/float voltages manually for LiFePO4, or does the Orion-Tr Smart have a dedicated LiFePO4 profile out of the box?

I'm looking at running something similar: 48V main bank down to a 12V Fogstar Drift for the cabin lighting circuit. Slightly nervous about getting the charge profile wrong and stressing the smaller battery. The price is eye-watering but if it just works reliably without babysitting I can probably justify it.