30 Days into using the Victron MultiPlus 12/1600/70-16 inverter and a Liontron 12V 80Ah with our Swift Sprite Caravan

The Caravan we got last year did not come with an inverter, so getting coffee in the morning or running a microwave was only possible when our main generator was running. And the installed battery for 12V support had a rather small capacity. This was clear to us from the beginning, as we eventually wanted to connect the Caravan to our EVE 280Ah cells.

But since we got our Starlink internet and our router did not seem to run easily on DC power, we needed -in addition to the temporary morning AC coffee spike – a more permanent AC solution.

So, I grabbed an existing Liontron 12V 80Ah battery that was sitting on the shelf along with a Victron Energy MultiPlus 12/1600/70-16 charger/inverter and connected the inverter AC Output to the CEE16-1 AC input of the caravan and the inverter AC Input to one of the phases of my JCB G20QS generator (of course, all via Neutrik powerCON TRUE1 TOP connectors and H07RN-F3G2.5 cable).

For the connection between the inverter and the battery I used a 35mm2 cable and Klauke DIN 46235 compression cable lugs on one end and insulated ferrules on the other end. In between, I added Anderson SB 175 connectors with 1383 lugs for quick disconnects and crimped as shown here. For the fuse I used a Schneider Electric 125A DC MCB, as I do not expect higher loads in this setup.

Of course, first I updated the firmware of the inverter and configured it work with the battery:

  1. Setting the AC input to 16A
  2. Setting the battery type to LiFePO4
  3. Setting the charge current to 70A (which is over the recommend amount of 50A, but see below for details)

As I did not want to connect a Cerbo GX to the system, I just used the VictronConnect App. Maybe I add a VE.Bus Smart dongle later on, or I connect some GX nevertheless. Who knows … Until now, it needs a wired connection to the inverter to see its status.

After powering on the generator, I confirmed everything was roughly working as expected. During the first run, the SOC was shown as 100% though the BMS of the battery internal saw it differently. In addition, the reported Amps and temperature were seen differently, as well. So, even that I set the inverter over the recommended maximum of 50A for the battery, the actual charge power was never much higher than the actual maximum).

This is what the inverter saw (100% SOC, 14.05V DC cell voltage, charging at 64A):

MultiPlus charging the Liontron battery via the generator

And this is, what the Liontron BMS reported (76% SOC, 13.8V DC cell voltage, charging at 55.5A):

The SOC as seen by the Liontron battery BMS

In the end, the BMS stopped charging when it thought its batteries were full. And the inverter did not complain. However, I noticed that the cells were really not in balance (with a delta of 200mV between the lowest and highest voltage).

Discharging was ok, as well. However, I soon realised that the 100A discharge current could not be achived in my setup. The inverter tried to draw power and the BMS cut off with a “Discharge over-current” (OCD). SO, still no coffee via our Nespresso machine (and no microwave either, for that matter).

So, what is the take away of all this?

  1. It works and now, I can run the Internet all day.
  2. All in all, it is a relatively simple and quick setup.
  3. The Liontron battery does somehow not live up to its specs (and yes, I know the battery could be a size bigger for what I want to achieve; but I did not want to buy an additional battery for this temporary solution).
  4. It is way cheaper and more flexible than to buy this “off the shelf”.
  5. Maybe, I add a Victron SmartShunt to get a more accurate SOC reporting (as I do not see any other way to integrate the BMS with the inverter).
  6. Charging of the battery is quite fast when running the generator.

New car – new electricity

48 system in a car and running everything from AC.

We are getting ready for our next car. Or at least start thinking about it. Roughly, we want something like a MB Sprinter (short version, normal roof) and built the interior ourselves. And of course, when doing this, electricity is one part of it.

In this post we give a brief explanation of our requirements, use cases and possible solutions we came up with.

Storage capacity in our existing Toyota is 5’120Wh brutto with two Liontron 12V @200Ah batteries costing around 1’990,00 CHF, which makes 0,77 CHF / Wh. For our next van we would like to increase the storage capacity and the larger inverter, but keep cost down if possible. Currently we use 35mm2 cables to run our 1’200W inverter, so to run a larger inverter we would have to increase cable sizes in our system significantly – or increase voltage size.

After some thinking, we opted for a 48V system (rather unusual for a car) with two Pylontech Us3000 batteries summing up to a net capacity of 6’400Wh. Considering the price for the batteries (arund 1’730,00 CHF each) this would lower the price to 0,54 CHF / Wh. With this capacity we could run an 3000VA / 2400W inverter and cable sizes could then even stay the same.

However, the main problem with that setup would be to get 48V from a 12V alternator. But luckily, we are not the first tasked with this problem and Safiery has a solution just for that: Safiery Scotty 12V-48V DC/DC converter at different power levels (1000W, 1500W, 3000W). As the car engine would have a 250A alternator, the setup could really benefit from even the largest model. Ideally the DC/DC converter would be installed in the engine compartment, in order to minimise the relative voltage drop on the way into pssenger area.

As we currently do not have a fixed solar system, this is definitely something on our wishlist. But with that large DC/DC inverter and the fact that we are not staying for days at a single spot without moving the van, the initial cost for 400W solar panels just do not seem to be justified. So, we thought we prepare everything, so we can later still install solar panels without having to redo a lot of installation work. Enter Victron Energy EasySolar-II 48/3000/35-32 MPPT 250/70 GX. Now, how does this roll of the tongue?

But in fact, that system really looks promising: in a H 499mm x W 268mm x D 237mm box at a weight of 26kg, you get

  • a 3000 VA inverter,
  • 250V/70A MPPT solar charger,
  • two AC out 230V @13A,
  • a communication controller (GX) with Can bus. USB, network connections (wired, wireless),
  • a 230V AC/DC battery charger with a 35A DC output (rather small),
  • programmable relays;
  • everything to be monitored and administered via a tablet,
  • options for future expandability such as LTE and GPS exist.

Now this is rather impressive if you consider the price span of 2’248,00 CHF2’469,00 CHF.

Considering, both the Scotty and the US3000 also have a CAN bus interface, this really make a neat paclage, as all devices are able to talk to each other. More bang for the buck.

At least in theory. As I have not built it yet. But I think, this is a good starting point. I will contact the vendors to get a response if my setup is supported and if there are any reference installations on it.

Now you might wonder, how I would charge my other 12V devices, as I do not have a single 12V output in the setup. And yes, I thought about this too, and came to the conclusion: I do not need 12V output. Or sort of.

Compressor, winch etc I will power from the alternator directly. All the rest I will power via AC, such as the fridge, mobile, USB, notebook. This of course, comes with a penalty, as I have to convert the energy twice. But this also saves me an additional device and a lot of cabling and extra fuse boxes (and this is all saved space).

Now about the weight:

  • the inverter I already mentioned
    26kg: EasySolar-II 48/3000 GX
  • 64kg: 2* Pylontech US3000
  • plus additional devices, such as 12V/48V DC/DC converter, bus bar, fuses, cables,
  • future solar panels would come on top (no pun intended).

The van (2-seater) has a total loading capacity of 1080kg, so I think this is a justifiable weight for a pretty massive power system.

For connection of these systems, I opted for a bus bar with integrated fuses, the Victron Energy Lynx Distributor, though a back-to-back-cabling with extra fuse boxes would also have worked.

In case, the interaction with Safiery, Victron and Pylontech via CAN bus does not work out as expected, I would insert a Smart BatteryProtect BP-220 in front of the Scotty, so I can switch the converter on and off depending on the ATD and ATC signal in the EasySolar via a relay.

System diagram: Van Electricity

So these are my plans for the next van. I am curious, what response I get from the vendors and how it all works out.

In case you have questions or recommendations for improvement, I am more than happy to hear from you.