This is the good shit. I’ll never use AGM in my van again.
I run a single 280ah 4 cell eve prismatic battery with a 120a BMS. It’s so much better than lead acid. Smaller, way more capacity, charges efficiently.
That said, @glyphiks run what you brung. You might find agm suits you just fine. I use my van battery to charge esk8 and ebike, so having a lifepo4 battery and knowing the exact SOC is very useful.
FYI all you’d need is a converter. The converter taps straight to the batteries. It’s not a complex system or anything. They’re not too expensive and pretty nice to have if you run into a stormy streak and can’t get enough power from solar/driving.
Fair point. But I think I’ll cross that path if/when I get to it, and still just run a cord in through a door or something.
For the most part I need to be entirely reliant on solar, as the van isn’t going to be travelling all that far daily, and running a lead to it won’t be on option where I want to park it.
If that means adding another solar panel and beefing up the dc/dc charger, then that’s the next upgrade
I tried hard to avoid plugging into the grid to recharge, but idling to recharge on a cloudy day, or driving when didnt need to drive, just to charge, was annoying and wasteful.
I found my 2/12/25 amp ‘smart’ charger to be dangerously dumb, when I did run an extension cord through door, to plug in, in desperation. It could not handle the cycling fridge, and often, I had only 2 hours to charge, and 25 amps were not enough.
RV converter/chargers are better at 3 stage charging lead acid while powering the DC loads other than the depleted thirsty batteries.
Most ‘garage’ battery chargers do a horrible job of returning deep cycling batteries above 92% State of charge, and this is a lead acid battery killer. They need 100% regularly.
When I got serious about achieving true 100% SOC on lead acid, I went adjustable voltage power supply, so I could choose the target voltage, hold it as long as necessary until ammeter showed amps into battery tapered to low enough to be considered “full”, if i had the time. If I had two hours only to charge from the grid, I wanted as much amperage as possible in the time allowed.
This ability to achieve and hold a proper absorption voltage easily doubled my LA battery longevity. The ability to get to 80% state of charge well before noon, so the solar has enough time to get the last 20% is also pretty vital.
Later on I modified my alternator’s voltage regulators to manual adjustable voltage too, as the stock voltage regulation was wasteful of time, and gasoline.
This manual adjustable voltage ability should make the transfer to Lifepo4 pretty simple, though cooking my alternators becomes more likely since Lithium can gobble so much more than Lead acid, if the BMS is large enough.
My first proper grid powered adjustable voltage power supply was a Meanwell RSP-500-15.
I modified it with more heatsinking, and a ten turn potentiometer for precise finger twist voltage adjustment, and Quiet Noctua fans to prevent its tiny screaming banshee fan from cycling on and off.
Rated for 500 watts, it can do over 600 all day long, at any voltage between 13.12 and 19.23v. 40 amps max, but 40 amps all day if needed. Wattmeters on output, and ideal diode too, so unplugging from AC, does not have battery powering Noctua fans or Columb counter.
Thousands of hours of use over the last decade. Its running 24/7/365 in my house bedroom now, powering fans and led lights which were in my Van. No 12 v battery on it at moment.
In my garage I have a beastly 100 amp adjustable voltage power supply 10.5 to 15.5v range. Extra fans and Ammeter and voltmeter. Keeps two GC-2 AGMs at 13.6v whenever I turn it on. Most all my ventilation and lighting in garage is 12vdc. I use a CCCV 150 watt, or 400 watt Voltage booster on 12vdc system, dialed up to 10s voltages for my esk8 battery.
I have 200 watts of solar on my van roof. It was usually enough in summer, not even close in winter. If I were to do it over, I’d aim for 400 minimum.
I do have a 100 watt flex panel I can plug into my MPPT. It fits behind windshield, but loses 50% through the glass.
Hmmmm there’s 320w of panels there right now and I have a 265W panel that would fit perfectly at the front of the car on the slope between the windscreen and the roof rack.
Only problem is that it was a solar panel for a house, and it says max 30V, so I’d need some fuckery to bring it down to 12v.
I don’t really want to install this panel unless I have to though, so again, it’s gonna come down to suck it and see with the gear that I’ve got.
During last summer, the 2 x 100ah batteries did just fine and they were always fully charged of an evening. I think I’ll be using more power this time around, but with the extra 100ah , should make up for it.
Definitely need to see how everything goes in winter though. That will be the real test.
320w will probably be great for you, especially in your part of the world.
I’ve got 400w of solar and I run a laptop and second monitor all day every day, along with lights and my fridge/freezer. That’s quite a lot of draw but the 400w keeps up with it most of the time.
Thats great.
I am looking forward to not having to pamper lead acid’s required long absorption stage, and making efforts to keep them above~ 50% SOC.
My 130 watt Kyocera panel has been installed since 2007.
It cost 740$ back then.
In 2012 i added a unisolar pvl-68 amorphous panel in parallel. Together that combo used to be good for 13.5 amps around noon summertime, but now maxes out round 11.5 amps with a Bluesky sb2512i Mppt controller. This October it will be 18 years of continuous use.
So as it turns out, the size of my solar box was giving me anxiety. It just didn’t feel right.
It took me the best part of the day, but I tore it apart and shrunk it. I ended up going even smaller than initially planned with a finished height of 175mm. I’m so much happier with how this looks and couldn’t wait to get it on the van.
Because I used up most of the hoist wood building the box, I had to improvise 
it went well.
The box secured to the racks well, with enough room in front for some kind of little air scoop, yet to be built.
The kayak also sits up there nicely with just enough space for me to move around up there as well.
Ran some power out into the awning for lights/fans/whatever.
Definitely feels like I’m making progress now!!
I’m guessing the laptop isn’t powered via USB-c PD?
If it can do that, i sure as hell don’t know how to make it do that 
it’s just got a 240v charger
Edit: it would seem that I can 
Internet tells me 100W can go through there
That’s one less 240V device!
You can purchase “car chargers” for most common laptops that step up 12v dc to whatever voltage your laptop uses. They usually come with a cigarette outlet plug.
The true goal of any self-respecting off-grid power system.
Hell; if @glyphiks would bypass the 240V to whatever step down that happens at the printer’s power supply, that would be sweet. 12V to whatever.
Pretty sure most printers run on 5V
Quick search says 12V or 24V.
I was just throwing an idea around, really.
I considered it but the bed needs 110
So it’s basically an iron.
You’re not gonna drive all the way to Byron Bay, are you? All dressed up in a linen shirt and pants, with a bead necklace…
One day I’ll get the van up to Byron… but fucked if I’ll ever iron my clothes!
You’re right; just pass by Nimbin and let the smoke steam your clothes smooth.
