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EV Camper - charging / battery / inverter

1876 Views 17 Replies 9 Participants Last post by  Ross Macdougall
I would like to replication what Glyn did with his eNV200.

Looking for help and advice, van is ordered but I have no measurements or specifications

I'm finding an all electric EV setup interesting in terms of rethinking the norms of power charging and consumption. For example, since we need to recharge the main battery when travelling we can also charge devices / cook at the same time. The "leisure" battery maybe does not need to have the same capacity than in a traditional van because the DC-DC charger can top-up when the van is turned on, and no driving needs to be done (unlike alternator).

  • Heating and AC during night
  • 12V Aux battery supplies 12V DC power and 240V via inverter (Phoenix 1200W)
  • Solar panel charges 12V Aux battery (thinking 400W panel)
  • Mains hook-up allows charging and 240V power overnight if available
  • Support 2 x 800W Induction hobs (all electric install) (assume no max power since 800W + 800W > 1200W)

  • Can OEM battery support inverter draw?
  • Will solar panels support Fridge consumpion during the day?
  • Is there a limit to the DC-DC built in charging provided from the Van?
  • Could the DC-DC charger support induction hob cooking for 20 mins (for example), how do I measure the DC-DC charge rate? Smart shunt?

Current thoughts:
  • Upgrade 12V aux battery. Not sure whether AGM or LiFePO4? Max physical dimensions? Minimum capacity?
  • No point having Multiplus, since van has built in DC-DC charger. Hoping solar will charge battery during day and support daily consumption.
  • Need to split shore power to van charger and 240V circuits, so it's not going through the battery (inverter) when not needed
  • Cooking may only be possible when at charging station or on camping hook-up. Depending on above
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Hi there.
While I'm not a camper guy, I can give my two cents here in regards to changing the 12v Lead-acid to Lifepo4:

I have been working on building my own 12v Lifepo4 as my EV's "starter" battery (instead of the heavy an inefficient SLA battery that the car comes with).

While I know that some Nissan Leaf owners have done this swap, I would strongly recommend against it. Especially in any PSA/Stellantis vehicles like my Corsa-e (or the Vivaro).

The main problem is that EVs have an onboard DC-DC converter. This converter is usually constant voltage (usually above 14v), which means that it's not suitable for properly charging a Lifepo4 battery (or any Lithium really).
I went through many loop-holes to try to step down the voltage and limit the current with my DIY Lifepo4. While I was partially successful, the car didn't like the Lifepo4 and would bring up a number of warnings/faults.

In the end I decided to save weight by switching to a smaller deep-cycle AGM. It's on order, haven't received it yet, but I believe it should be fine. Lithium batteries have a very low internal resistance in comparison to Lead-acid, so they will "pull" a huge amount of charge from the DC-DC converter. This is both not safe for the Lithium and not recommended for the DC-DC converter's lifespan.

So in short, my recommendation is not to touch the 12v battery life, but just add a Lifepo4 leisure battery and charge it up with solar and/or a proper B2B (battery to battery) charger. There are some one the market like the Victron Orion Tr Smart and the Renogy DC-DC.
Just make sure that you choose a model with the correct charging amperage for your leisure battery.
Also, keep on mind that most EV's onboard DC-DC converters are rated at 1400w-1800w.
You don't want to run them at full load, as this can cause them to overheat and prematurely fail. So do your math properly...

While in theory you could just connect a 12v inverter directly to the car's 12v battery, I wouldn't do this for prolonged times and wouldn't pull more than a few hundred watts...

I think that adding a leisure battery with separate charging is the best solution for a camper van. This will also allow you be more flexible if you need (add more capacity, etc...).
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