Swapping my leisure battery to LiFePO4

[Salty Spuds]

I'm about to swap my lead acid battery out for a Super B Epsilon Lithium battery. We spend a fair amount of time "Stealthing" it both winter & summer, and the current 110ah battery is getting tired & isn't up to the job anymore. This is our current setup:-

1, 110ah Lead acid under passenger seat
2, 130 W solar panel
3, 15 A mains charger under drivers seat to charge the leisure battery when on EHU.
4, Ctek Dual250 b2b under the passenger seat by the battery, this handles the Solar & B2B charging.
5, Ctek "Stop Start" charger under drivers seat, this is connected to the starter battery to keep it charged when parked up for long periods.

I'm proposing the following changes:-
1, SuperB Epsilon 90ah Lithium battery with built in BMS & Bluetoooth.
2, Ablemail AMS 12-12-30 reprogrammed with a Lithium charging profile, this will replace the Ctek Dual. AMS12-12-30 | 0161 745 7697
3, A mains charger around 15A that will charge Lithium, open to suggestions, but I'm trying to get away from cooling fans if poss. Victron do one with a "Night time" setting to reduce the fan noise. Can't see that Ablemail do one.
4, Keep the Ctek "Stop Start" charger.

One thing that occurs to me looking at the Ablemail, is that the ignition sense comes off the van battery to start the Ablemail charger. If I have the Ctek "stop start" connected, will the Ablemail see this as the engine running & try to draw current from the van battery/charger combo? I would have thought that the "Sense" line would be from an ignition controlled source.

Do Ablemail make a mains charger?

Any thoughts?

 

[t0mb0]

I think, for preference, the "sense" input on the ablemail should probably come from the D+ input which is only high when the engine is actually running. This is provided under the passenger seat if a factory leisure battery was fitted, if not, I'm not sure where it can be picked up from. Second best would be an ignition feed although this is presumably still high when the engine has turned off through start/stop.

Looking at the wiring diagram though for the ablemail, that sense line is hooked straight up to the battery - seems very strange. Maybe it needs additional software configuration to hook up to a D+/ignition feed.

 

[Salty Spuds]

All done & dusted
The spec changed somewhat after taking advice from the battery supplier.
OptiMate mains charger under drivers seat
Victron Smart Solar 75/15
Sterling BB1230

 

[Dieseldonkey]

I'm sure I was told the Ablemail keeps harvesting from the vehicle battery until it drops to a certain voltage, (which off hand I cant recall the value). Hence the sense or signal wire direct off the positive terminal. So even when the engine is off, your leisure battery keeps getting charging until the aforementioned voltage is reached on the vehicle battery. Someone can correct me if that's wrong. Maybe @travelvolts can confirm that I've got that right.

 

[Bryn23]

I ended up just using the main centre mini fuse box for my D+ input for my Votronic Triple Charger (DC-DC, Solar and 230 volt) connected to a 240ah Lithium battery , i can't say i've noticed it still draining from my main battery after turn off the engine with the key out.

 

[Grim Reaper]

Are you using the ctek charger via an inverter to charge the starter battery off the leisure battery or is it solely for when on mains hook up?
I’ve fitted a victron 100Ah lithium which charges via a redarc bcdc from either the alternator when the engine is running or solar when it’s not, but if the starter battery is depleted (say from the interior lights or having the radio on) whilst away from a mains supply I have no way to get some charge back into it even if the victron is fully charged from solar input while I’ve been on site (no mains hook up)
I need a way to charge the starter battery if the unthinkable happens, either direct from the lithium leisure battery or indirectly via an inverter and a charger.
Not sure if just connecting the two batteries together via say a redarc SBI12D will work or if there’s the risk of too much current flow from the full to the dead battery.
Half an amp via an inverter and a charger for an hour or two wouldn’t put too much strain on the leisure battery especially if it is getting a simultaneous charge from the solar panel, but it seems an inefficient way of doing it.
It’s a shame the redarc bcdc can’t automatically back feed to the starter battery when a situation like this arises and the leisure battery is in a better state of charge than the starter battery.

 

[Loz]

If the D+ is not available, you could trigger from the lift pump feed wire.

 

[Salty Spuds]

Are you using the ctek charger via an inverter to charge the starter battery off the leisure battery or is it solely for when on mains hook up?
I’ve fitted a victron 100Ah lithium which charges via a redarc bcdc from either the alternator when the engine is running or solar when it’s not, but if the starter battery is depleted (say from the interior lights or having the radio on) whilst away from a mains supply I have no way to get some charge back into it even if the victron is fully charged from solar input while I’ve been on site (no mains hook up)
I need a way to charge the starter battery if the unthinkable happens, either direct from the lithium leisure battery or indirectly via an inverter and a charger.
Not sure if just connecting the two batteries together via say a redarc SBI12D will work or if there’s the risk of too much current flow from the full to the dead battery.
Half an amp via an inverter and a charger for an hour or two wouldn’t put too much strain on the leisure battery especially if it is getting a simultaneous charge from the solar panel, but it seems an inefficient way of doing it.
It’s a shame the redarc bcdc can’t automatically back feed to the starter battery when a situation like this arises and the leisure battery is in a better state of charge than the starter battery.

The little Ctek only charges the van battery when on hook up. I’m not too concerned about flattening the van battery in normal “holiday” use. It’s not likely that we’re going to be parked up on a campsite for any length of time without either starting the van or being on hookup. It’s more for when it’s parked up at home between trips rather than “on the road”. I suppose at a push I could short the input & output at the Sterling B2B & let the van battery soak up some charge from the Lithium. We don’t use the van radio when parked up & everything else runs of the leisure battery.

 

[Dilbert]

Sterling BB1230

Looks a nice job.

Interesting you have got the Sterling BB1230 mounted on one side vertically. I also have a Sterling BB1230 mounted in a similar position and same orientation under the passenger seat. However, I angled it so the lower side is towards the front to ensure the fan cooling exhaust vent had adequate room to exhaust the hot air when on peak charge. I also placed a metal plate underneath the lower vent area to deflect the hot air off the carpet. The air flow from the heatsinks gets pretty hot when on the maximum 30A charge into a low battery.

 

[Stay Frosty]

At Grim Reaper and a noob question but couldn't you effectively jump start your van battery from the lithium leisure one using a single manly jump lead live post to live post with the vehicle body common to both neutral posts being the other lead?

 

[Salty Spuds]

Looks a nice job.

Interesting you have got the Sterling BB1230 mounted on one side vertically. I also have a Sterling BB1230 mounted in a similar position and same orientation under the passenger seat. However, I angled it so the lower side is towards the front to ensure the fan cooling exhaust vent had adequate room to exhaust the hot air when on peak charge. I also placed a metal plate underneath the lower vent area to deflect the hot air off the carpet. The air flow from the heatsinks gets pretty hot when on the maximum 30A charge into a low battery.

I hadn’t considered the amount of heat, I’ll keep an eye on it.

 

[Grim Reaper]

At Grim Reaper and a noob question but couldn't you effectively jump start your van battery from the lithium leisure one using a single manly jump lead live post to live post with the vehicle body common to both neutral posts being the other lead?

I didn't want to do that. The Victron Superpack has a limited output current, max continuous is 50A, with 10 seconds of 100A. I think I'd prefer the option of just trickle charging the starter battery on the odd occasion it might need a top up, more controlled input and less likely to damage any of the components

 

[Grim Reaper]

Further to the above, I have now changed the starter battery from a 70Ah Moll EFB+ to a 95Ah Bosch AGM and I'm immediately seeing better response from the battery. My CTEK comfort indicator is now staying green rather than dropping to red almost immediately after charging/driving. I may not need the charger for the starter battery but will include it in the underseat collection along with a Victron Phoenix 12/800 inverter that I've just ordered.

 

[mutantspy]

hi all
i have a 2018 t6 sport line converted by redline conversions the leisure battery seems to have gone past its best as goes down to 10.2 volts from 12.4 after just draining the water tank for ten mins.
i am looking to upgrade the battery to a lithium one the battery is under the drivers seat i have a solar panel sorry im not very literate when it comes to electrics but can do diy projects
the electrical components are in the rear panel drivers side easily accessible
there is a solar charge controller unit and an
ec160 sargent power supply unit.
can any one tell me if it is possible to exchange the battery for the lithium one by just reconnecting the + and - terminals to the lithium battery.
or do i need to do some electrics with new components as i'm changing from a deep cell
battery to a lithium one.
any help would be gladly appreciated before i end up taking it to a garage and taking out a second mortgage for the privilege.

 

[Pete C]

Lithium needs a different charging profile which I don't think your Sargent device can provide. Your solar controller needs to have a Lithium profile too.
So no, you can't just swap the battery out.
Show us some photos of what you have and you will get good advice here.

Pete

 

[mutantspy]

here are just two i can get more if needed
what would be the best configuration with what i already have for longer off grid camping

 

[mutantspy]

forgot to say thanx pete for getting back to me cheers

 

[mutantspy]

here's a couple more pics the battery is under the drivers seat. would it be possible
to get another battery next to it. i would
buy two new batteries and fit them
at the same time would i have to do any work on the charge controller or the power supply

 

[roadtripper]

If you don't want to change your chargers then the only way to get more capacity is a higher capacity battery... and that means usually a physically larger one and that tends to be the limitation in a T6/6.1 - that's also why many folks are moving to lithium.

If you add capacity by adding 2 batteries then they need to be identical make/type/capacity to work well and ideally bought together. This is the approach used on the higher spec California's as they have a second leisure battery in the rear cupboard and one under the seat. Keep in mind you should only discharge lead cause to around 50%, whereas lithium is great to 80% and fine on the longer life cells to 90%

Your chargers should work but the downside will be recharge time as both seem to be about 10-15A which is fine for 100aH (using the advised 50% capacity recharge in about 5 hours) but will double if you double your capacity.

End of the day the "classic" van leisure electrics with and all in one power system and a lead acid battery are good for a weekend off grid with a modern compressor fridge and some careful eye on consumption. To do more you need to move to a lithium based system.

If you're not ready to look at that then the best bet is to replace your battery like for like with a good quality equivalent.

You could also consider adding to it by buying one of the portable lithium power packs. That might directly take some electrical load of you can use that, you could use it to top up your leisure battery with a maintenance charger and if you had a portable solar panel on sunny days when you are in the van you could get the power pack to top itself up (almost all take a solar panel input)

 

[mutantspy]

ok so to get into changing the chargers to accommodate a lithium battery is it possible to do it as a diy project or is it a garage with electricians to do the job.
if it is a diy job like swapping over the wiring to a new solar controller and power supply unit and reconnecting the battery and a new charger where do i start