Can you mix lithium batteries

Al n Val

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Hi everyone

i’ve got 2 Super B 90Ah lithium batteries fitted as standard on my Rapido, i’m wondering whether or not if it’s possible to add a 3rd Roamer 100Ah lithium battery in parallel to my Super B’s.

All batteries have there own built in BMS so does anyone with battery knowledge know if this setup will work ok or can you see me having problems

Thanks for any help offered

Al
 
Defo, not recommended with different manufacturers due to different bms and voltage settings/needs, AL.

BUT if lets say you are thinking of getting a new set in the near future and dont mind damaging or get less then best performance from the ones you mix and match till that happens, then maybe.

Id sell and renew tbh.
 
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Hi everyone

i’ve got 2 Super B 90Ah lithium batteries fitted as standard on my Rapido, i’m wondering whether or not if it’s possible to add a 3rd Roamer 100Ah lithium battery in parallel to my Super B’s.

All batteries have there own built in BMS so does anyone with battery knowledge know if this setup will work ok or can you see me having problems

Thanks for any help offered

Al
Hi Al
1st response from me would be give roamer a call as you said they all have a BMS 👍
 
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The Super-B 90ah uses cylindrical cells as opposed to the more usual Prismatic cells, I don't know if this makes a difference when mixing and matching, how about selling the two 90ah's and getting a 210ah or even the new 340ah Super-B ;) you know you want to really:LOL:
 
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Although it should work without any problems but as you have Super B's you would be better fitting another Super B they are far better than most other Lithium's. The Super B has a very high discharge something like 1.5c or above if fit a diffent battery which has BMS limiting it to say 0.5c if you draw high currents the Super B's will supply most of the power so they are not going to discharge evenly.

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There’s a video on YouTube that tested this very scenario (different manufacturers, massively different pack sizes and, IIRC, different cell types) and concluded that they performed perfectly satisfactorily under both charge, and discharge, scenarios.

As usual, I didn’t bookmark the video so you’ll have to search for it.

Edit: found it quite easily Paralleling Different LiFePO4 Batteries Test

Ian
 
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There’s a video on YouTube that tested this very scenario (different manufacturers, massively different pack sizes and, IIRC, different cell types) and concluded that they performed perfectly satisfactorily under both charge, and discharge, scenarios.

As usual, I didn’t bookmark the video so you’ll have to search for it.

Edit: found it quite easily Paralleling Different LiFePO4 Batteries Test

Ian
I’ve watched that video before and just rewatched it again, it’s making me think that it’s worth a shot tbh

I’ll watch part 2 tomorrow as a pint is calling me 😉
 
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Although it should work without any problems but as you have Super B's you would be better fitting another Super B they are far better than most other Lithium's. The Super B has a very high discharge something like 1.5c or above if fit a diffent battery which has BMS limiting it to say 0.5c if you draw high currents the Super B's will supply most of the power so they are not going to discharge evenly.
I agree Lenny it’s best to keep the same but to stick with Super B will cost me circa £2k just to add another single 90Ah

or replace all with a large 460Ah is £4.5k which doesn’t sit well with me tbh

This experiment will cost me £325 if it works or nothing if it doesn’t so i’m pretty keen to give it a shot and see what happens

As long as nothing blows up i’ll be happy
 
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The Super-B 90ah uses cylindrical cells as opposed to the more usual Prismatic cells, I don't know if this makes a difference when mixing and matching, how about selling the two 90ah's and getting a 210ah or even the new 340ah Super-B ;) you know you want to really:LOL:
I’ve got mine for sale Martin at half price but no takers or that would be the way i’d be going tbh

Ah well, onwards and upwards
 
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Hi Al
1st response from me would be give roamer a call as you said they all have a BMS 👍
It’s def worth a call to them Mike but I think they’ll just tell me to bin mine and buy a big Roamer one and i’m not prepared to do that just yet 😉

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I agree Lenny it’s best to keep the same but to stick with Super B will cost me circa £2k just to add another single 90Ah

or replace all with a large 460Ah is £4.5k which doesn’t sit well with me tbh

This experiment will cost me £325 if it works or nothing if it doesn’t so i’m pretty keen to give it a shot and see what happens

As long as nothing blows up i’ll be happy
Where are you getting your prices from?
100 ah Super B is around £1200, 90 ah is obsolete.
Best place to buy them is Holland not sure if you can buy them direct from the factory.
 
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Defo, not recommended with different manufacturers due to different bms and voltage settings/needs, AL.

BUT if lets say you are thinking of getting a new set in the near future and dont mind damaging or get less then best performance from the ones you mix and match till that happens, then maybe.

Id sell and renew tbh.
That’s what i’m trying to do but without success, sell and renew I mean 😉

I love a big 460Ah battery and be done with it

That said over here in Spain with only the solar charging my Super B’s they are rarely less than 90% and back up to 100% before 12 ish and we are using the inverter to power the kettle and toaster regularly, especially the kettle so i’m not sure if I need to

But you always need something to spend the kids inheritance on don’t you, or I do 🤣

C2005784-3DCE-4459-8B14-246B7397B485.png
 
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Where are you getting your prices from?
100 ah Super B is around £1200, 90 ah is obsolete.
Best place to buy them is Holland not sure if you can buy them direct from the factory.
it’s what i’ve been quoted by a local ish to me firm

Where have you seen them at £1200?
 
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it’s what i’ve been quoted by a local ish to me firm

Where have you seen them at £1200?
Holland my mate has a Carthago on order with one and he reckoned that was the cheapest option if he adds another one.
Went in Suber B stand at Caravan Salon they were quoting €1500 in Germany.
 
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I would say definitely not. When I wanted to add additional 210ah Super Bs’ to my new Motorhome. I messaged Super B who were very helpful. They wanted the serial numbers from my existing Super Bs’. They got back stating I could add them given the two existing batteries were less than 6 months old and had to ensure they were fully charged before adding the new batteries.
Strangely, for the first few months all went well until the undervoltage tripped and all power went off although the Buttner shunt was showing 48% left. Batteries were charged and thought nothing more of it. I then fitted the Super B battery monitor. When I connected then all up I heard a very distinct click from the relays on both of the new batteries. I assume that they were never in service hence the undervoltage tripping, the two batteries most have been discharged. I read a few other people having exactly the same issue and discovering the problem when connecting the Super B monitor and it putting all connected batteries into service.

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I would say definitely not. When I wanted to add additional 210ah Super Bs’ to my new Motorhome. I messaged Super B who were very helpful. They wanted the serial numbers from my existing Super Bs’. They got back stating I could add them given the two existing batteries were less than 6 months old and had to ensure they were fully charged before adding the new batteries.
Strangely, for the first few months all went well until the undervoltage tripped and all power went off although the Buttner shunt was showing 48% left. Batteries were charged and thought nothing more of it. I then fitted the Super B battery monitor. When I connected then all up I heard a very distinct click from the relays on both of the new batteries. I assume that they were never in service hence the undervoltage tripping, the two batteries most have been discharged. I read a few other people having exactly the same issue and discovering the problem when connecting the Super B monitor and it putting all connected batteries into service.
I guess that’s why when Premium added our last battery they moved all the bi-stable relays and put them all in series, they said it would stop one battery dropping out and not being spotted.
 
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We’ve tested mixing different BMSs and found that as long as you set the same HVD and LVD it’s fine. The most important thing is that all the BMSs should use MOSFETs and not conventional relays.
 
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Holland my mate has a Carthago on order with one and he reckoned that was the cheapest option if he adds another one.
Went in Suber B stand at Caravan Salon they were quoting €1500 in Germany.
I’d be interested in a link Lenny please as i’ll not be ordering a new Carthago just to get a bigger battery 😂
 
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The Super-B 90ah uses cylindrical cells as opposed to the more usual Prismatic cells, I don't know if this makes a difference when mixing and matching, how about selling the two 90ah's and getting a 210ah or even the new 340ah Super-B ;) you know you want to really:LOL:
KS use cylindrical, would that be an option?

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So i’ve just spoken to Roamer, they told me it would work but technically it’s not good practice as the batteries will be constantly trying to balance each other and shorten they’re life. 🤔

Obviously he didn’t say by how much or whether it would really matter as I doubt no one would really know.

He went on to say that 1 large single battery is better than 2 smaller batteries, easier to managed and £500 cheaper, and the 460Ah sale price of £1750 ends in 2 days 😉
 
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they told me it would work but technically it’s not good practice as the batteries will be constantly trying to balance each other

That would only happen if one was faulty; when they’re charged they’re charged and any minor difference in charge level would soon be resolved. There wouldn’t be a constant battle trying to balance. Methinks they’re fobbing you off.

What do they think happens internally when the cells are balancing one another in a single battery?🤷‍♂️

Ian
 
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That would only happen if one was faulty; when they’re charged they’re charged and any minor difference in charge level would soon be resolved. There wouldn’t be a constant battle trying to balance. Methinks they’re fobbing you off.

What do they think happens internally when the cells are balancing one another in a single battery?🤷‍♂️

Ian

Ian

tbh i’ve been sat here thinking exactly the same 🤔

My mate who has the battery is keeping hold of it for me so when we are back in the uk in around 3 weeks we’ll be fitting it so watch this space.

Each having their own app, and the fact the Roamer app seems to provide a lot more information should provide the info needed to see if all is either going well or belly up
I have to say I think the Super B is a bit lacking in the info department bordering on crap 👍
 
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Ian

tbh i’ve been sat here thinking exactly the same 🤔

My mate who has the battery is keeping hold of it for me so when we are back in the uk in around 3 weeks we’ll be fitting it so watch this space.

Each having their own app, and the fact the Roamer app seems to provide a lot more information should provide the info needed to see if all is either going well or belly up
I have to say I think the Super B is a bit lacking in the info department bordering on crap 👍

The only proviso that I’d make is that in the video the chap made sure that the BMSs were set up appropriately so I’d play close attention to what he did/recommended there.👍

Ian
 
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I’d be interested in a link Lenny please as i’ll not be ordering a new Carthago just to get a bigger battery 😂
Gone up €100 since September.

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Gone up €100 since September.
I wish I could speak European Multilingual

I’m thinking with vat and import duties that would be nearer to 2000 euros 😟🤔
 
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I wish I could speak European Multilingual

I’m thinking with vat and import duties that would be nearer to 2000 euros 😟🤔

I use Google Chrome browser and set it to translate, other than that as Lenny says the Dutch are very multilingual.



Screenshot 2023-03-22 at 12.09.25.png




Screenshot 2023-03-22 at 12.09.51.png
 
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Hi everyone

i’ve got 2 Super B 90Ah lithium batteries fitted as standard on my Rapido, i’m wondering whether or not if it’s possible to add a 3rd Roamer 100Ah lithium battery in parallel to my Super B’s.

All batteries have there own built in BMS so does anyone with battery knowledge know if this setup will work ok or can you see me having problems

Thanks for any help offered

Al
To be honest theres no point these days. The lithium batteries you can buy now are massive. You can get 400ah plus in one battery. Very expensive but space saving. If you use a big inverter make sure the bms allows high amp out put. E.g a 2000watt inverter can pull 160 amps the new roamer batteries allow a 250amp drawdown.
 
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