How to monitor all Victron NG battery temperatures simultaneously

Running 4x Fogstar Drift 100Ah in my van and this exact thing has been doing my head in for months! 🔧

So here's the situation — each battery has its own internal temp sensor, but getting all four readings on one screen simultaneously feels like it shouldn't be this hard in 2024.

What I've managed so far:

• Victron Cerbo GX shows temps, but only if the batteries are communicating via VE.Can or Bluetooth properly
• The Venus OS interface on my GX Touch 50 will display individual battery data, but you have to faff around navigating between devices rather than seeing everything at a glance
• Third-party dashboards like Node-RED running on the Cerbo seem promising — anyone actually got this working cleanly?

The cold months are where this really matters for those of us in the UK — charging lithium below 5°C is a brilliant way to ruin expensive cells, so knowing every single battery's temp in real time isn't just nerdy — it's genuinely protecting your investment.

My current bodge is checking the VictronConnect app and manually tapping through each battery, which is about as elegant as duct-taping a solar panel to a wheelbarrow.

Surely someone here has cracked a proper simultaneous readout? Whether it's through MQTT, a Raspberry Pi setup, Home Assistant integration, or something else entirely — I'm all ears.

What's everyone else doing for multi-battery temp monitoring? Especially curious if anyone's running more than 4 units and keeping tabs on the whole lot without losing the plot. 👀

@VoltMax mate, four batteries and you've only just lost your mind after months? Respect the patience — I'd have rage-sold the lot to someone on Facebook Marketplace by week two.

The trick with multiple Fogstar Drifts is daisy-chaining your BMS comms into a Cerbo GX and then using VRM Portal to pull all the temp readings onto one dashboard — each battery shows as a separate device node once the DVCC settings are sorted properly.

If you haven't got a Cerbo yet, a Venus GX does the same job for less, and you'll find second-hand ones floating around on here regularly.

Alternatively, stick a cheap Ruuvi Tag sensor on each battery externally — not perfect but at least you'll know which one's quietly plotting against you before it becomes exciting.

@VoltMax the Fogstar Drifts report temperature via their BMS over their respective comms, but the trick is getting it all aggregated cleanly. If you're running a Victron system, a Cerbo GX is your friend here — pair each battery's BMS data through a USB-RS485 adaptor or the native VE.Can network depending on your BMS output, and the Cerbo will display all four temps simultaneously on VRM.

Worth noting the Drift's internal BMS doesn't always expose temperature over the standard UART by default — check your firmware version. Some earlier units needed a manual parameter tweak.

I run a similar multi-battery setup in my motorhome and the VRM app gives me per-cell temp logging historically, which is genuinely useful for spotting a rogue cell before it becomes a problem. Don't overlook setting high-temp disconnect thresholds in your charge profile too.

@SimonKelly genuinely curious how you'd pull all four temps into one dashboard without it turning into an absolute spaghetti situation behind the panels 😅

On my narrowboat I've got a similar headache with backup batteries — I ended up using a Victron Cerbo GX which can handle multiple VE.Bus/CAN connections, but whether the Fogstar Drifts actually talk nicely to it over all four instances simultaneously is something I've never fully cracked.

Does anyone know if the Cerbo sees each Drift as a separate BMS device in the device list, or does it just lump them together and you lose individual cell temp data? That's the bit that matters for proper thermal monitoring rather than just knowing "something somewhere is warm."

@SunnyFisher I ran into exactly this with my garden office build — three Fogstar Drifts, Cerbo GX as the hub. The trick that sorted it for me was using a Cerbo's VE.Can bus with each battery connected via the RS485-to-CAN adapters. All four temps then land natively in VRM as individual data streams. No spaghetti, just a clean dashboard.

The gotcha nobody mentions: you need to set unique CAN IDs on each battery or the Cerbo just sees one device repeatedly. Took me an embarrassing afternoon to figure that out.

Once it's right, VRM historical graphs show each battery's temp overlaid — genuinely useful for spotting if one cell group runs hotter than the others under load.