Van of enormous power Mk 4

[Moxi]

Cheaper versions of that on Amzon but still pricey - ask Colin if he has anything comparable?

Moxi

[Stinsy]

Here is a diagram:



Once you've recovered from laughing at my poor diagram-drawing skills hopefully you can understand how the system will work. Pretty much all of it is very simple and requires very little thought. The only part that requires thought is the disconnect between the Leisure battery and the starter battery. Obviously you could have them completely separate however then you'd not have the ability to charge the starter battery from your solar panel / leisure battery in the event that you leave the lights on or whatever and additionally you'd not have the ability to charge the leisure battery from the alternator when you're driving down the motorway. You also don't want them connected all the time because then you could flatten the starter battery with your domestic loads and that defeats the object of having separate batteries, and other is the small problem of the alternator...

I've mentioned this a few times. I don't want to overblow it. However, while the standard alternator is the perfect voltage to charge a 4s LiFePO4 battery pack, the Lithium batteries will pull more current than the alternator can deliver at idle. This will let the magic smoke out of the alternator if you don't take steps to mitigate. A 1m length of 1mm² wire (eg the earth stripped out of a bit of T+E) wound round a broom-handle to form a helix, then removed from broom and mounted in a suitable enclosure, will have a resistance of about 17mΩ this will slow down the charging enough to keep the smoke in your alternator. Alternatively, you could have a switch on the dash that you press to control a relay that connects the two systems. And yet another solution is to simply fit a different pulley on the alternator.

[resybaby]

Do you want cold beer and to worry about refilling a propane canister?

We all know you want to do this...

That's a good one!

There is a split when looking to run the 12V basic system or step up to a 48V lifepo4 system. One needs a couple of LV100W panels and a low cost solar controller along with a bit of cable and voila the 12V LB is charging and the crank battery is getting a trickle. Can maybe dick about and chuck in a 0.5kW inverter and sockets..

The other needs a big ass panel.(cheap) but then all the ancillaries to go with it. 4pack 280lfks, solar controller and a decent sized inverter.

Il sit down and see what's running what when I get back. I know I've got domestic water and habitation space lights running off the LB....cold beer though eh?

I wouldn't put a 48V LiFePO4 system in the van unless you're running a takeaway or something! just go for 4x cells and 12V, all your current stuff would run off it fine.

Id do this too.

My Transporter has two 100w 18v panels on the roof feeding into two 135ah lead acids via a relatively cheap chinese solar controller. I didnt both hooking up a split charge system off the vehicle alternator as would need to lift up the fitted rubber/sponge factory floor in the van and it would never go back down as well.
Main thing to look at is the consumption of the fridge as the biggest permament power user. I have a Waeco Crx50 fridge freezer, and its quite happy to feed that and the lights and stay charged - although i goofed up and parked under a tree on a site once and then it didnt

[Joeboy]

Here is a diagram:



Once you've recovered from laughing at my poor diagram-drawing skills hopefully you can understand how the system will work. Pretty much all of it is very simple and requires very little thought. The only part that requires thought is the disconnect between the Leisure battery and the starter battery. Obviously you could have them completely separate however then you'd not have the ability to charge the starter battery from your solar panel / leisure battery in the event that you leave the lights on or whatever and additionally you'd not have the ability to charge the leisure battery from the alternator when you're driving down the motorway. You also don't want them connected all the time because then you could flatten the starter battery with your domestic loads and that defeats the object of having separate batteries, and other is the small problem of the alternator...

I've mentioned this a few times. I don't want to overblow it. However, while the standard alternator is the perfect voltage to charge a 4s LiFePO4 battery pack, the Lithium batteries will pull more current than the alternator can deliver at idle. This will let the magic smoke out of the alternator if you don't take steps to mitigate. A 1m length of 1mm² wire (eg the earth stripped out of a bit of T+E) wound round a broom-handle to form a helix, then removed from broom and mounted in a suitable enclosure, will have a resistance of about 17mΩ this will slow down the charging enough to keep the smoke in your alternator. Alternatively, you could have a switch on the dash that you press to control a relay that connects the two systems. And yet another solution is to simply fit a different pulley on the alternator.

Holy canasta Batman! Mucho gracias for all this. I've had 3 gnt 's so unlikely to process b4 tomorrow. I need a solid week away in the van and I'll know the weakspots for Euro travel. Any upgrades are really just for convenience and coz I like it. I need to get East East and see what's there but mibbees that a small amount of time not really worth the big buy in? Dunno, still letting back brain circulate.

[Krill]

Do you want cold beer and to worry about refilling a propane canister?

We all know you want to do this...

That's a good one!

There is a split when looking to run the 12V basic system or step up to a 48V lifepo4 system. One needs a couple of LV100W panels and a low cost solar controller along with a bit of cable and voila the 12V LB is charging and the crank battery is getting a trickle. Can maybe dick about and chuck in a 0.5kW inverter and sockets..

The other needs a big ass panel.(cheap) but then all the ancillaries to go with it. 4pack 280lfks, solar controller and a decent sized inverter.

Il sit down and see what's running what when I get back. I know I've got domestic water and habitation space lights running off the LB....cold beer though eh?

At the risk of saying something stupid...there is the same potential energy stored in 16 cells, whether you align them as a 4p4s or 16s. They weigh the same, and take up roughly the same space (the wiring setup notwithstanding).

In other words, what's the downside to building a 12V system compared to a 48V system? If the 12V system needs a greater battery capacity, it should be expandable. If you don't have the space, you don't have it for the 48V system either.

I agree on the sockets and 500W inverter being worth exploring, I was wondering if such a system could be charged from mains if you were on a powered site etc. It's the same logic as running a house and recharging a battery whilst on the IOG cheap rate. I know I'm interested in seeing how you would do something like this.

[Stinsy]

Do you want cold beer and to worry about refilling a propane canister?

We all know you want to do this...

That's a good one!

There is a split when looking to run the 12V basic system or step up to a 48V lifepo4 system. One needs a couple of LV100W panels and a low cost solar controller along with a bit of cable and voila the 12V LB is charging and the crank battery is getting a trickle. Can maybe dick about and chuck in a 0.5kW inverter and sockets..

The other needs a big ass panel.(cheap) but then all the ancillaries to go with it. 4pack 280lfks, solar controller and a decent sized inverter.

Il sit down and see what's running what when I get back. I know I've got domestic water and habitation space lights running off the LB....cold beer though eh?

At the risk of saying something stupid...there is the same potential energy stored in 16 cells, whether you align them as a 4p4s or 16s. They weigh the same, and take up roughly the same space (the wiring setup notwithstanding).

In other words, what's the downside to building a 12V system compared to a 48V system? If the 12V system needs a greater battery capacity, it should be expandable. If you don't have the space, you don't have it for the 48V system either.

I agree on the sockets and 500W inverter being worth exploring, I was wondering if such a system could be charged from mains if you were on a powered site etc. It's the same logic as running a house and recharging a battery whilst on the IOG cheap rate. I know I'm interested in seeing how you would do something like this.

Absolutely there is the same stored energy in 16x LF280k cells arranged 4s4p and 16s.

The benefit of 48V is more manageable current levels for higher power usage. Certainly there is an argument that 12V is nolonger an appropriate for automotive systems, but while there is a 12V system in the van and pretty-much every electrical item designed go in a van is 12V, it’d be silly to go with any other system voltage. And I think you only need a single string of 4x batteries anyway. 3.5kWh should be plenty for anyone.

The: one panel, 4 cells, 12V appliances, and small (maybe 1200W) 230V inverter, has an elegance to it. It is a miniature version of what Joe has in his house.

[richbee]

My current van has a Ctek 20A dc to dc leisure battery charger,which also contains an mppt solar input and the trickle charges the starter battery once the leisure battery is full - has worked an absolute treat for the last 5 years.
Only problem from a solar point of view is the max voltage /current for the solar panel, limits the size of panel.

I'm looking at a larger van for my next project, to include an mtb garage and a shower room, so it will need more solar this time & a bigger battery etc.....

[Krill]

I can see a case where a greater battery capacity would be desirable if the van was being used in wintery conditions though. And it would be a better buffer for hot weather where the fridge might be kicking in more often (plus it would allow another solar panel to be added). Just on gut feeling I reckon an 8 cell system would be worth looking at.

[Joeboy]

Had a dive in the Red Sea today. Absolutely epic, the fish variety, Octopus, coral. Truly a game changing experience. I left a little bit of my heart at that dive site.

I thought it would be just another dive. WAY more than that!

SWMBO owning the space.

[Stig]

Had a dive in the Red Sea today. Absolutely epic, the fish variety, Octopus, coral. Truly a game changing experience. I left a little bit of my heart at that dive site.

I thought it would be just another dive. WAY more than that!

You're making me jealous! Broke my leg 2 weeks ago, new hip now and recovering but not even allowed in the pool for 3 months