I’m looking for some advice on the best way and most efficient way to charge my Bluetti whilst in the van. The setup is solar on the roof connected to the leisure battery via the victron mppt. I have various 12v sockets in the back of the van currently (usb/cig lighter style).
Now I can currently plug into the 12v socket and into the xt60 connector on the elite 100v2 but the charge is slow so looking for a quicker option.
Any ideas greatly welcomed
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Charger 1 from the alternator will give up to 560W input directly to the Elite 100.
The only way of getting more than <100W from a 12V input into the Elite 100 is to increase the voltage of the input.
The math is 12V x 8A = 96W max. When DC charging under 30V, the charge amps are limited to 8A.
Charger 1 has a variable voltage output up to 56V @ 10A = 560W.
I actually power my Charger 1 from the Auxiliary battery of my 4x4, which is charged by its own inbuilt 20A DC-DC charger from the alternator. I did this as I limit the Charger 1 voltage to 29V. This gives me approx 235W input, with a load of roughly 20A from the Aux Bat. This gives me a neutral in/out load, other than the 3A for my Engel fridge/freezer.
Have a look at this info I posted recently, it details input loads and expected output. Charger 1 Info
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I guess you are in the U.K. as you call the Auxiliary battery a leisure battery. I’m down under. 
That said, having grown up in the U.K. your reliance on sunshine is geographically limited as the only charging option. Even here in AU, winter sun is sometimes limited, so it’s all about options i.e. DC-DC, petrol generator etc.
Rarely does a vehicle have a large enough roof footprint to install enough solar, dependent on usage requirements.
I have multiple charging options, as I off grid camp 99.9% of the time and in remote areas, here, running out of power can mean hundreds of kms to get help.
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I do have dc-dc charger already set up. Can the charger 1 be used alongside this? I’m looking for a charging option for when stationary really. Turning the engine on would be last resort when on a campsite. Usage isn’t overly high
Hello, we suggest you consider purchasing charger 1, which can greatly improve the charging speed.
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Are charger 1 and DC40 only usable when on the move? The bluetti will be fully charged before we leave home so charging it on the go isn’t really needed. It’s whilst we are stationary that a quicker charge would be great if possible. If either charger 1 or DC40 can be utilised whilst parked up that would be great
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@MStep - Neither should be used from a start battery when not being driven, it will quickly flatten. So No, only on the move.
The D40 is primarily meant to convert the 48V DC output of the AC200L to a usable charging voltage for house batteries, not for the Elite 100 to be charged as it is only in the 14V range. It has a min 45VDC input.
Consider this, you have a house battery in your camper and an Elite 100V2, both need charging at some point and if static, these are your options - Solar panels, grid power (shore) in a caravan park, petrol generator and or from the vehicle when the engine is running. (Idling the engine for several hours and not moving, is not recommended.) Using Charger 1 gives you the higher charge to your Elite 100. You could then transfer it’s power to the house battery via a 240VAC charger if installed in your camper.
A further option is something I use, but is limited to capacity. I have a spare 100Ah LFP deep cycle battery along with the Charger 1 to boost the LFP’s 13VDC to a higher voltage and therefore charge rate to the Elite 100. This adds 1,300Wh to my power station capacity. But it then needs a recharge, along with any other batteries carried.
Note: The Charger 1 is not a multi stage charger as are most DC-DC chargers. It can be viewed as a variable output voltage booster, from a start battery or other battery. It does not have a charging algorithm for LFP house batteries. That it works on power stations is because they have their own inbuilt MPPT/DC charger that does have that algorithm.
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@MStep Martin, Your limitation using a DC-DC + the Charger 1 is your total alternator usage. i.e.
I have a secondary battery with an inbuilt DC-DC @ 20A, a DC-DC in the caravan @ 25A, adding the Charger 1 at full load of around 45A gives a total added alternator load of 90A. This is more than I am happy to draw.
So, my first rule is to never use the C1 when towing the caravan. However, once camp is set up, I disconnect the 4x4 and that releases 25A for use and is the main reason I have not installed the C1 (permanent wiring).
As I have rear bumper mounted Anderson plugs as well as the 2nd battery having Anderson connection, I use it as a plug n play, along with the spare 100Ah LFP.
You need to work out your loads, a clamp Ammeter on the primary negative start battery will give you your loads. Checking specs of your vehicle alternator to compare its capability…
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Thanks for the replies, really appreciate them. I should have been clearer, when I said using it when not moving I was thinking if I could connect to the leisure battery (house battery). The leisure battery is charged currently via solar and dc-dc from starter when in motion.
From what you have said your set up is I could potentially connect the Charger 1 to the leisure battery the Bluetti to charger 1? The bluetti will drain power from the leisure battery but this will be getting topped up by solar. This will also produce a quicker charge of the bluetti than if I just used a normal 12v socket. If this is correct this could work as a setup?
Absolutely, my 4x4 secondary battery is the same as your setup, solar on the roof (110W) and DC-DC charged from the alternator.
The only difference is that I also have 2 x 100Ah in the caravan and a spare 100Ah to draw from as well.
Apart from the 110W on the 4x4, I also have a 160W on the caravan roof, 2 x 150 Hard Korr solar mats and 2 x 120W solar blankets for on ground use. Gives me a total max solar of 810W.
Although the 4x4 on roof, caravan on roof and blankets are flat, not angled at the sun, so their total of 510W would be lucky to get 70 to 80% of that for around 360 to 400W actual in good sun.
FYI - We are at the tail end of winter here and it was nearly 24C yesterday, with rain today, lol. Cloudy yesterday, my on house solar is a 6.6kW array into a 5kW inverter and I still got 16.6 kWh, in summer it’s nearer 50kWh.
So, climate and weather make a huge difference on smaller units as well.
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