Can I mix battery types?

[Teesix]

I need to upgrade my leisure battery, as it's a lowly 80ah gel jobbie, and I could do with something a bit beefier. The starter is 70ah but that seems to be fine so it can stay.

I fancy a LifePO4 as the leisure battery. But can they be mixed and can the ah be different? I seem to remember reading that they had to be the same type of battery. I do have a Redarc DC-DC charger, so was wondering if that would make it possible/ok to mix them?

What you you think?

 

[Dellmassive]

Technically you can provide they are they same chemistry and voltage. (Ie, two lithium batteries 12v one of 100ah and one of 50ah )

But the basic answer you will get is no. Leisure battery lithiums should be a matched pair from new.

A 100ah lithium will give you twice the power as a 100ah AGM... So you will have loads of extra run time.

Make sure you're redarc has a lithium profile, and set it to that....

And leave the starter battery as it's is. Ie AGM or EFB+

 

[Salty Spuds]

If I’ve read and understood the question correctly. You want to keep your existing starter battery, bin the current LB & replace it with a lithium. Assuming the redarc DC-DC has a lithium profile, then that’s a perfectly normal scenario. The redarc will deal with the difference in battery chemistry & capacity, between your starter & LB.

 

[Teesix]

If I’ve read and understood the question correctly. You want to keep your existing starter battery, bin the current LB & replace it with a lithium. Assuming the redarc DC-DC has a lithium profile, then that’s a perfectly normal scenario. The redarc will deal with the difference in battery chemistry & capacity, between your starter & LB.

Yes, that's exactly what I meant. Brilliant! I'll go for it then. Thanks for the advice.

Thanks also @Dellmassive

 

[Teesix]

Just another quick question: I'm looking at getting this battery, but it appears the lithium terminals aren't the two lumps of lead I'm used to seeing. Is that some sort of cover that gets removed to allow the connectors to be attached, or do I need some sort of adaptors?



Also, mine is a right-hand positive. Seems these are not as plentiful as left-hand positives. In fact, I can only find 2. This one and a Victron.

 

[Dellmassive]

That's the current standard format for lithium leisure batteries...

That's definitely not a starter battery replacement.

But if you plan on using that as an upgrade for your leisure battery then it comes with a terminals by a bolts in the box.

They are normally in 8 mm bolt .

You will need to get some end crimps on your cables and bolt them on to the battery via your fuses

Are you as a fused bus bar etc.

 

[Teesix]

Yes, it's a leisure battery replacement. I'll get the end crimps ordered. Thanks for that.

Whilst you're there, if you don't mind. You used to run a Redarc on one of your earlier vans. Can you remember where I can find the dip switch to apply the lithium mode? Mine's a 1240D. I'm pretty sure it has the lithium profile, but I can't find any dip switches to activate it.

 

[Dellmassive]

No switches on mine

You use the wires to join together or connect to a positive or connect to a ground.

On my previous one you had to join the orange and green wire together to select the lithium profile.

See below...

You can download the install guide from red arc to double check for your specific model number.



.

Post in thread '[Guide] DC-DC Charger (for leisure battery) -- How I Done It --'

4 May 2020

DC-DC Charger Test/Review . . .

REDARC BCDC1250D Sn-00035 =]

( first in UK when i got it from @travelvolts )
( i got the Victron Orion 12/12/30 from there too)
( Electrics | Travelvolts )



This time we have the Redarc BCDC1250D, now I've already got a BCDC1240LV and love it to bits . . .

in fact it might be my favorite DC-DC charger yet, due to its small compact size, rugged design and simplicity.

So why change ? (Redarc> Orion> Renogy> Redarc)

well this one is 50A where as the old one was 40A and this new one is the "D" version meaning it can take Solar input too. Oh...

• Dellmassive

.

 

[Teesix]

Brilliant, thought I was going mad trying to find the switch. The wire thing looks straight forward enough though.

Thanks a lot, much appreciated.