Charging lithium from the Alternator

[colinm]

50 to 100 miles per day driving when away.

But how does that charging work? As I posted when driving ours only charges via the EBL at 18amp, switch off the EBL and the battery will not charge. Is yours the same or does it have some type of split charger

 

[Pudsey Bear]

The durite is a VSR, there is no fancy charging set up that I know of Colin, and had the van for four years.

Is this what you have?

 

[colinm]

Ours is similar to that.

 

[Pudsey Bear]

Mine looks like a 240v incomer with a red illuminated switch for the charger. There is another box of goodies under the rear seat/bed, but all you see are fuses. But there is zero way to change settings, so I have to assume it's a dumb charger.

 

[wildebus]

The durite is a VSR, there is no fancy charging set up that I know of Colin, and had the van for four years.

Is this what you have?

View attachment 145109

It is an "Electrobloc" not Electric Block, also referred to just as ELBs
It is made by Schaudt (who is now owned by Lippert, an American company) , who in a way are the German version of Sargent - they make lots of different versions of the ELBs. In the same way as if you have a British motorhome, chances are you have a Sargent system, if you have a German Motorhome, you probably have an EBL system.
I fitted an Ablemail AMT12-2 maintainer to one of those EBL119s just a few days ago as it happens

For driving, the EBLs just have a relay split-charge setup, no B2B, and is activated by the D+ signal rather than a voltage like a VSR is.
As an aside, your info says "batteries are charged when solar power is being used". Just for clarification, the EBLs (or at least most, including the one in the image) do not have a solar regulator/controller in them. They have a connection where you can connect up the output of the solar controller, but you need the controller - connecting up a panel to that connection would mean putting 20+V onto the battery.

This is where my brain freezes David, no idea what exactly a B2B is, but I have one of these https://amzn.eu/d/iKxw9fW to send charge to the LB from the VB when the engine is running, & Merlin's Gizmott to do the same in reverse when parked up to a lesser degree.

I'm not 100% convinced I actually need Lithium. Lead acid has been fine, but the idea of a drop in appeals, but as said, no pennies have been harmed yet.

Well, there is no such thing as a "drop in" Lithium unless you have a system that is ready to take Lithium. If you read the small print on these websites, there is usually a caveat to the "drop in" comment saying it is drop in when you have a van with compatible chargers.

Ref B2B, a Battery-to-Battery Charger is the same as a Smart Mains Charger, but instead of taking the power from 240V AC and converting it, it takes it from the Alternator and converts it to the voltage the battery wants.
The difference between that and something like a VSR is the relay does no conversion, so you have no charge profile and optimization of charging the battery. The key feature a B2B has that is important to the alternator and what sparked this thread is it limits the current to the rating of the B2B. IF you just connect the battery to the alternator (which is what you are doing with a relay when on), the only limits are down to the resistance of the setup. With Lead Batteries, that tends to be its own limitation due to their internal resistance. With Lithium, the batteries have a very small resistance and so would try to suck up as much power as they can get, which could be more than the alternator can handle. Some people deal with that by using very long cables to add resistance, but a more sensible way (IMO anyway) is to use a B2B which does that for you as well as having other benefits.
(yes, I am simplifying the picture, before the links to Wikipedia articles start appearing )

Personally, from what you are describing, I would suggest to stick with what you have, but replace your dying Leisure Battery with a Lead Carbon battery.

 

[barryd]

Cost is a big issue Barry, and I don't use much when not driving, so 100ah is more than enough I think.

Actually given the amount of driving you do and your low usage why bother at all? If your battery is a bit dodgy just get the biggest lead acid that will fit, drop it in and forget about it. Remember I was about to hit the button on a £3k Lithium system when Merl and one or two others convinced me not to bother. Best decision I ever made. I don't see the point in going Lithium unless your going to go gasless and / or run big power hungry 240v appliances.

 

[Pudsey Bear]

All good points, and as said still in the thinking phase.

Lead carbon is also new to me, I don't think my controller has a setting for that, so is that a true drop in? As the money is similar to LA.

 

[Pudsey Bear]

Is this a lead carbon battery or not? price looks similar to LA

Amazon.co.uk

 

[wildebus]

Is this a lead carbon battery or not? price looks similar to LA

Amazon.co.uk

No

All good points, and as said still in the thinking phase.

Lead carbon is also new to me, I don't think my controller has a setting for that, so is that a true drop in? As the money is similar to LA.

Lead Carbon has same charging characteristics as Standard Lead Acid. You can get them as GEL or AGM so would choose settings for those.
To give you an idea of if they are better than standard Lead Acid, before Lithium was a big thing, Victron had a range of Batteries utilising Lead Carbon and they marketed them as "Immortal" as they had such a better service life and could be taken down to dead and then recharged without damage.
You will pay more for a 100Ah Lead Carbon than you would a typical Lead Acid, same as you would pay more for a Lithium than a Lead Carbon, but installing Lead Carbon is much simplier, is a genuine drop in in all but the most unusual cases and will both last longer and can be discharged deeper so Amp for Amp over the life of the batteries they are cheaper.

 

[Pudsey Bear]

Can you recommend a fairly cheap one? as that was the only one that came up on Amazon.

Very out of my depth now lads.

 

[Fisherman]

No


Lead Carbon has same charging characteristics as Standard Lead Acid. You can get them as GEL or AGM so would choose settings for those.
To give you an idea of if they are better than standard Lead Acid, before Lithium was a big thing, Victron had a range of Batteries utilising Lead Carbon and they marketed them as "Immortal" as they had such a better service life and could be taken down to dead and then recharged without damage.

David correct me if I am wrong but are you saying you can completely discharge a lead carbon battery without damaging it. Or are Victron making this claim. My understanding is that the max discharge was down to 40%, but doing this on a regular basis would shorten the life of a lead carbon battery.

 

[wildebus]

You can discharge all the batteries down to dead, but the lead carbons don't get damaged by doing so, whereas the 'normal' leads do.
Cycles will get reduced doing this frequently, same as any battery, inc Lithium would.
I say "dead" rather than 0% SOC as the voltage would get too low to be usable for most purposes before getting to 0% (10.8V)

I set my LC discharge limit to around 40% as a preferred lower limit but I wouldn't care about them going to 30% or even lower on occasion.
If you look at the data sheet of a Lead Carbon battery they will typically include cycle count for a battery taken to 0% (and that count is often more than a basic leisure battery like a Lead Banner Bull)

 

[mikejay]

Just fitted a victron mppt 100/20 and a orion xs50 I was really surprised how small the orion was compared to my old sterling 121250 which was just a hunk of ally heatsink and 3 fans the orion is smaller than the mppt controller that is about the same size as the tracer 10a it replaced.

Mike

 

[barryd]

I don't think our lead acid batteries have been down to less than 80% usually 90% since Merl fettled it all which is about 12.5 or occasionally 12.4 and that includes a week or more without moving the van. Be interesting to see how they cope in autumn.

Do you go off grid much in the colder off season months Kev?

 

[Pudsey Bear]

Yes, if we can, we will go away in December or January.

 

[barryd]

Yes, if we can, we will go away in December or January.

What's your current battery ah? If your moving about each day 50 to 100 miles with your low usage you won't need much I don't think.

 

[trevskoda]

Mine looks like a 240v incomer with a red illuminated switch for the charger. There is another box of goodies under the rear seat/bed, but all you see are fuses. But there is zero way to change settings, so I have to assume it's a dumb charger.

Have you thought about the numax duo 30amp.
No good for liths mind you if you plan to change.

 

[Pudsey Bear]

100ah, but it's well fecked, I put the chair battery on charge the other day and the volts fell out of the vans drop out vents.

 

[Nabsim]

It's not how many miles a day you drive, it's how long a day you drive. In some parts of Scotland in Winter 50 miles can easily be a couple of hours which would just about do me for topping up with.my 30A B2B. Down South on normal roads I would either be holding everyone up or have to drive a lot further in my 2 hours

 

[Pudsey Bear]

We do tend to drive most of the day, less so in the UK though.

Not found a single battery so far labelled as Lead Carbon.