Mix FLA and Lithium with this?

[Frank B]

I have a large solar array on our TT, but our 6 GC-2's are showing their age. I like the idea of Lithium, but we are getting older and don't know how much more we want to invest in the RV lifestyle. Our resources, personally and monetarily, are dwindling.

A friend sent me this:

Emily & Clark's Adventure - BankManager™ BBMS

NOW AVAILABLE BankManager™ System Combine Lithium (LiFePO4) and Lead-Acid Batteries in the same system, and charge everything optimally. Introducing the BankManager.

www.emilyandclarksadventure.com

Anyone have any experience with this?

Thanks!

Frank.

 

[Mark_K5LXP]

If your lead is crapping out it doesn't add a lot to keep the current bank and add lithium. Seems you're in it for one or the other. If your power needs are modest maybe go with a smaller bank of either one and supplement with genset as needed.

Mark B.
Albuquerque, NM

 

[Frank B]

If your lead is crapping out it doesn't add a lot to keep the current bank and add lithium. Seems you're in it for one or the other. If your power needs are modest maybe go with a smaller bank of either one and supplement with genset as needed.

Mark B.
Albuquerque, NM

Valid analysis, and the one that I am considering now.

The long-winded video makes sense, though probably not enough sense for us at the moment. I may just tough it another year with what we have and reconsider then.

 

[Mark_K5LXP]

A data point I would want to know is exactly what the current bank's capacity is, so you know what kind of Ah might be sufficient. If you need all of your 660 Ah then fine but if today you're getting by with some fraction of that maybe you could scale it back a bit.

Mark B.
Albuquerque, NM

 

[Frank B]

Thanks, Mark. I go by the adage that no one ever complains about having too much solar.

1230 Watt Solar Install

The price of residential solar panels is coming down as the popularity of home solar goes up. Residential panels are often 72 cell operating near 40VDC. The more common ones use 6" ingots to produce the panel, making them about 39" wide. A few use 5" ingots, giving a panel that is about 32"...

www.rvforum.net

If anything, I could use more storage. However, that will have to wait for another day.

Thanks for your interest.

Frank.

 

[Gary RV_Wizard]

6 x LA 6v's is somewhere between 630 and 690 AH. Either 210AH/pair or 230AH/pair.

You didn't describe the charging system on your present battery bank, but chances are it can adequately charge lithium batteries. Note I said "adequate" rather than "optimal". And conceivably you can get by with a few less amp-hours of Li batteries (depending on how you currently use & manage batteries).

That said, another set of 6 GC2's should last you 6-10 years with zero modification. Is that within your RVing horizon? If so, what do you expect to gain by changing horses?

If you do decide to go with lithium, why would you need a device to mix LA with them? Are you thinking you would not replace all 6 LA at once?

 

[Tulecreeper]

6 x LA 6v's is somewhere between 630 and 690 AH. Either 210AH/pair or 230AH/pair.

You didn't describe the charging system on your present battery bank, but chances are it can adequately charge lithium batteries. Note I said "adequate" rather than "optimal". And conceivable you can get by with a few less amp-hours of Li batteries (depending on how you currently use & manage batteries).

That said, another set of 6 GC2's should last you 6-10 years with zero modification. Is that within your RVing horizon? If so, what do you expect to gain by changing horses?

If you do decide to go with lithium, why would you need a device to mix LA with them? Are you thinking you would not replace all 6 LA at once?

That was my understanding from the OP, which is not recommended.

 

[Frank B]

If you do decide to go with lithium, why would you need a device to mix LA with them? Are you thinking you would not replace all 6 LA at once?

The whole idea behind the link I posted was with regard to the ADVANTAGES of mixing FLA with Lithium.

I think that this answers @Tulecreeper as well.

In the final analysis, I will probably just replace all 6 FLA batteries, but not until next year. I have 5 years on this set, and they still work. I have been easy on them, but nothing lasts forever. And, in the immortal words of Gary RV Wizard: "Batteries are a consumable, not an heirloom".

Thanks, all.

 

[gwinger]

FLA'a and Litium batteries require different charging methods. Your converter may not be able to charge the lithiums when on shore power.

 

[Frank B]

FLA'a and Litium batteries require different charging methods. Your converter may not be able to charge the lithiums when on shore power.

I think you may have missed the video that I linked in my original post.

 

[Gary RV_Wizard]

The whole idea behind the link I posted was with regard to the ADVANTAGES of mixing FLA with Lithium.

I don't think there are any inherent advantages to mixing. It's something you do out of necessity if there are other reasons for doing so. Some examples might be economic (can't afford to replace all at the same time), differing applications (want to use LA for engine cranking but LI for aux power), or have multiple charging sources with differing charge profiles (optimal charge rates).

RVs and boats often have some or all of those, so some sort of smart management may be a worthwhile upgrade. The Bank Manager doesn't seem especially smart - all it appears to do is prevent the LI from being overcharged (and potentially damaged) by opening a relay to prevent additional charging. I don't see any function that adjusts voltage or amp rate for optimal charging of either battery type. Unless I've missed something in the BankManager description, any smarts concerning charge voltage or amp rates has to come from an external charge regulator or the battery's own BMS. If your charger doesn't produce enough voltage to fully charge an LI battery, BM isn't gonna change that.

 

[Frank B]

I don't think there are any inherent advantages to mixing. It's something you do out of necessity if there are other reasons for doing so. Some examples might be economic (can't afford to replace all at the same time), differing applications (want to use LA for engine cranking but LI for aux power), or have multiple charging sources with differing charge profiles (optimal charge rates).

RVs and boats often have some or all of those, so some sort of smart management may be a worthwhile upgrade. The Bank Manager doesn't seem especially smart - all it appears to do is prevent the LI from being overcharged (and potentially damaged) by opening a relay to prevent additional charging. I don't see any function that adjusts voltage or amp rate for optimal charging of either battery type. Unless I've missed something in the BankManager description, any smarts concerning charge voltage or amp rates has to come from an external charge regulator or the battery's own BMS. If your charger doesn't produce enough voltage to fully charge an LI battery, BM isn't gonna change that.

That is the sort of information I was looking for, Gary. Thanks.

Like I say, it was a friend that passed that link on to me. I wondered if there was anything to it, and it appears not. Too many snake oil items like this on the market, so I was just looking for some counsel on it.

I did consider adding one lithium battery as a way to extend the service life of my weakening lead acid array. But like you suggested in your original answer to me, just replacing the GC2s will be simplest, and likely cheapest in the long run.

Thanks again for the good input.

Frank.

 

[Gary RV_Wizard]

I wouldn't call it snake oil, but it's not a panacea either.