Mains Charger and mixed Batteries?

Jon magowan

Jon magowan

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Hello all.
Pretty sure I’m going down the Lithium route.
So I’ll have a lead acid starter battery and a lithium leisure battery.
I recently had a Victron shore power charger fitted and it seems to be working fine. But all my batteries at the moment are lead acid.
My question is, how will the charger cope with having two different battery types? Presumably this device can only be programmed to follow one type of charging regime ?
 
KevinV said:
In typical PBO style I won't answer the actual question (because I can't) but will instead ask why you need to charge your starter battery? It should be full after use?
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Good point !
Hopefully someone else could clarify this please ?
At present my starter battery is connected to the charger and always assumed that it should be !
 
This is MY view on the matter and could likely differ from others :

Engine Start battery - I cannot imagine NOT having this connected to a charger .... the last thing I want is a start battery unable to start that engine !! Not everyone uses their boat every weekend / few days ... and long idle times can lead to low battery charge.
Domestic batterys - of course could be pulled into use to start that engine ... but for me I regard charging domestic as secondary to engine start battery.

I know plenty people go on about DC-DC chargers - to avoid conflict of Li and LA formats ... but Li batterys are evolving and BMS controllers are fitted to many now that literally will allow normal charging .... its a case of careful choice of battery.

To OP - I would have a discussion with an electrician who services boats and such systems ... you may end up with a different solution .. who knows !
 
Sandy said:
@Jon magowan you could always put a small solar panel onto the, isolated, engine battery if away for some time just to keep it topped up.
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Ironically, the previous owners fitted a small solar panel, but it’s actually connected to the domestic bank !

Still not sure I’ve got an answer to my original question , one way or the other !
 
Jon magowan said:
Hello all.
Pretty sure I’m going down the Lithium route.
So I’ll have a lead acid starter battery and a lithium leisure battery.
I recently had a Victron shore power charger fitted and it seems to be working fine. But all my batteries at the moment are lead acid.
My question is, how will the charger cope with having two different battery types? Presumably this device can only be programmed to follow one type of charging regime ?
Click to expand...
I had to buy a special charger when I bought a lithium battery (but some years ago) so I would expect the answer to your question is that no the charger won’t cope.

This is not advice just encouragement (and forewarning to start saving money incase a new charger is needed ) to do as others have said and seek expert opinion.

One solution (if charger won’t work with two types) is to buy a simple solar system (so cheap these days) for one battery type and keep current charger too.

Will watch this with interest.
 
Jon magowan said:
Hello all.
Pretty sure I’m going down the Lithium route.
So I’ll have a lead acid starter battery and a lithium leisure battery.
I recently had a Victron shore power charger fitted and it seems to be working fine. But all my batteries at the moment are lead acid.
My question is, how will the charger cope with having two different battery types? Presumably this device can only be programmed to follow one type of charging regime ?
Click to expand...
Need to know the model of Victron charger and exact type of lead acid battery Jon, but it is possible for Lithium and LA to be charged by a single charger. The profile may not be 100% perfect for the lead acid, but acceptable.

If you're having these professionally installed the installer should know all of this.
 
Not lithium but my boat has a mixture of lead acid (engine & domestic) and AGM (bow thruster). The Cristec charger has 4 DIP switches where you select the battery type. Having spoken to Exide and Cristec, they both said set the charger to the battery type with the most capacity (in my case, lead acid domestics).

The charger had been set to AGM and if left on trickle, the lead acids would gas and set the CO alarm off. I set it to lead acid open type and the issue has stopped.

cristec_batt_type.jpg
 
wonkywinch said:
Not lithium but my boat has a mixture of lead acid (engine & domestic) and AGM (bow thruster). The Cristec charger has 4 DIP switches where you select the battery type. Having spoken to Exide and Cristec, they both said set the charger to the battery type with the most capacity (in my case, lead acid domestics).

The charger had been set to AGM and if left on trickle, the lead acids would gas and set the CO alarm off. I set it to lead acid open type and the issue has stopped.

View attachment 193550
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The Lithium settings on there are wrong.
 
PaulRainbow said:
Need to know the model of Victron charger and exact type of lead acid battery Jon, but it is possible for Lithium and LA to be charged by a single charger. The profile may not be 100% perfect for the lead acid, but acceptable.

If you're having these professionally installed the installer should know all of this.
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Thanks Paul,
Yes I’ll be getting someone who knows what they’re doing to install this. Just trying to get my head around the setup.
I’m hardly the first to have gone down this path. I thought a bunch of people would have come out with a definitive answer, either ‘don’t worry it will be fine’ or ‘ no, you definitely need a separate charger’.
How naive of me !

PS. Charger is Victron IP22, starter battery is standard LA and I’m planning to get a Fogstar lithium domestic.
 
I'm wary of online forum advice TBH - apologies to forums - because I am sure that some setups are not as good or recc'd as some would think ...

Often there will develop 'argument' between 'factions' which does not help.

I use Li and various other forms of batterys (not on boat) - and try not to mix them. If I do - I try to isolate each to own setup.
 
Refueler said:
I'm wary of online forum advice TBH - apologies to forums - because I am sure that some setups are not as good or recc'd as some would think ...
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Where do you recommend to get advice?

I have seen the same 'factions' develop in academic, work and social settings.

Part of the wonderful dialog between humans is eventually a consensus evolves. Personally, I see no place for Lithium for 99% of UK based leisure sailors, but when I come to replace my 5 year old AGMs might consider them IF they fit in the available space AND my insurance company does not need them to be professionally* fitted.

* whatever professionally fitted means.
 
Sandy said:
Where do you recommend to get advice?

I have seen the same 'factions' develop in academic, work and social settings.

Part of the wonderful dialog between humans is eventually a consensus evolves. Personally, I see no place for Lithium for 99% of UK based leisure sailors, but when I come to replace my 5 year old AGMs might consider them IF they fit in the available space AND my insurance company does not need them to be professionally* fitted.

* whatever professionally fitted means.
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I agree that Lithium isn't necessary for lots of boats, sometimes an extra lead acid battery or some solar is all that's needed. For others though, it's a complete game changer, especially now prices of dropped considerably. About 4 years ago 2x200Ah Victon batteries were £3,300 ! Today, the same batteries are half of that, but then i'm building 314Ah packs, with a BMS, configured and ready to go for £560.

Space isn't really a consideration. A 314Ah pack has a similar footprint to a 100Ah SLA battery.

314Ah Lithium = a conservative 250Ah of usable power, 300Ah LA 150Ah at best, when new.

314Ah Lithium = 20kgs, 300Ah LA = 90kgs and the Lithium takes up 1/3rd of the space.
 
PaulRainbow said:
I agree that Lithium isn't necessary for lots of boats, sometimes an extra lead acid battery or some solar is all that's needed. For others though, it's a complete game changer, especially now prices of dropped considerably. About 4 years ago 2x200Ah Victon batteries were £3,300 ! Today, the same batteries are half of that, but then i'm building 314Ah packs, with a BMS, configured and ready to go for £560.

Space isn't really a consideration. A 314Ah pack has a similar footprint to a 100Ah SLA battery.

314Ah Lithium = a conservative 250Ah of usable power, 300Ah LA 150Ah at best, when new.

314Ah Lithium = 20kgs, 300Ah LA = 90kgs and the Lithium takes up 1/3rd of the space.
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I have limited height where the batteries are, hence have 'low profile' AGMs.

Ran a test on Friday, used 55 Ah overnight and by 1100 UTC, with 200 watt solar was back to 100% SOC according to Victron.
 
Sandy said:
I have limited height where the batteries are, hence have 'low profile' AGMs.

Ran a test on Friday, used 55 Ah overnight and by 1100 UTC, with 200 watt solar was back to 100% SOC according to Victron.
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Yours is obviously one of the "lots of boats" where Lithium doesn't make sense.
 
Jon magowan said:
Thanks Paul,
Yes I’ll be getting someone who knows what they’re doing to install this. Just trying to get my head around the setup.
I’m hardly the first to have gone down this path. I thought a bunch of people would have come out with a definitive answer, either ‘don’t worry it will be fine’ or ‘ no, you definitely need a separate charger’.
How naive of me !

PS. Charger is Victron IP22, starter battery is standard LA and I’m planning to get a Fogstar lithium domestic.
Click to expand...
You could most likely get away with setting the charger for Lithium and connecting to the starter battery, but i'd be inclined to fit a small solar panel and/or a separate, small mains charger.
 
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