Theoretical Question on charging LiPo Batteries using stock controller

[bandityo]

So, I have a transcend with the solar package. I know it charges the wet cell battery with the correct setting on the charge controller and camper controller. If one did just drop in a lithium battery, I understand the stock controller will not have the proper charge parameters for lithium and maybe only charge it to 80% or so.

So in theory, if you switched the included furrion solar charge controller to Lithium, just dropped in a lithium battery... and left the factory non lithium controller in the camper... wouldn't the solar charge controller top off the lithium battery to 100% with good sun, essentially taking over where there onboard controller stopped?

david

[Guest]

If you disconnect the Furion controller or disabled it.....Yes. You can swap out the Furrion with a high quality Victron unit which can charge any battery chemistry once the parameters are loaded in. Get the Blue Tooth version which makes this easy through their app.

Jim

[TucsonJim]

If you disconnect the Furion controller or disabled it.....Yes. You can swap out the Furrion with a high quality Victron unit which can charge any battery chemistry once the parameters are loaded in. Get the Blue Tooth version which makes this easy through their app.

Jim

I think your might have misunderstood the question Jim.

The converter is a WFCO, and David is correct that it will not 100% charge a LiFePO4 battery. But the Furrion solar controller can be set to LiFePO4 charging. So the question is "won't the Furrion MPPT controller top off the battery anyway, even with the WFCO converter?

The answer is that as long as there is adequate sunlight, you should be able to achieve 100% state of charge with Furrion controller finishing up the charging profile.

Jim

[Paul & Deb]

So, I have a transcend with the solar package. I know it charges the wet cell battery with the correct setting on the charge controller and camper controller. If one did just drop in a lithium battery, I understand the stock controller will not have the proper charge parameters for lithium and maybe only charge it to 80% or so.

So in theory, if you switched the included furrion solar charge controller to Lithium, just dropped in a lithium battery... and left the factory non lithium controller in the camper... wouldn't the solar charge controller top off the lithium battery to 100% with good sun, essentially taking over where there onboard controller stopped?

david

Not a theory, a reality. This is exactly what I did on my last trailer. Now we live in Southern California, but our lithium batteries were always fully charged even though we never switched out the factory converter.

[Guest]

I think your might have misunderstood the question Jim.

The converter is a WFCO, and David is correct that it will not 100% charge a LiFePO4 battery. But the Furrion solar controller can be set to LiFePO4 charging. So the question is "won't the Furrion MPPT controller top off the battery anyway, even with the WFCO converter?

The answer is that as long as there is adequate sunlight, you should be able to achieve 100% state of charge with Furrion controller finishing up the charging profile.

Jim

Whoops.

The WFCO can be disabled as I have done, by turning off the breaker. Then a Progressive Dynamics unit was mounted in the passthrough for the lithium battery. This allows for flexibility on the system to use both battery chemistries but not both at the same time. WFCO also sells a LiFeP04 unit that is switchable between lead acid or Lithium that would be a simple option.

For the solar controller. install a Victron.

Sorry if I misunderstood the question.

Jim

[bandityo]

Thanks guys, I thought that it may work that way, just trying to find a more cost effective, albeit less traditional way, of topping off the lithium from existing solar charge controller where the onboard left off.

david

[Guest]

Thanks guys, I thought that it may work that way, just trying to find a more cost effective, albeit less traditional way, of topping off the lithium from existing solar charge controller where the onboard left off.

david

Here is an option that would work exceptionally well. This WFCO is a direct replacement and has a switch to change charge modes between lead acid and lithium. One member heard a rumor where this unit was not going into bulk mode but I would try it and see how it functions because user error can be the real issue. It can always be returned if its not delivering. Or you can swap out the converter portion of the power distribution center.

https://parts.unitedrv.com/products/...-8955pec-b-lis

https://www.amazon.com/WFCO-WF-8950L...3052780&sr=8-1

Jim

[Country Campers]

Guest

Jim,

The OP does NOT want to change the converter. The Furrion Solar controller can be set to Lithium , from that the controller should finish the charge on the Lithium battery from where the stock converter left off.

Brian

[Guest]

Guest

Jim,

The OP does NOT want to change the converter. The Furrion Solar controller can be set to Lithium , from that the controller should finish the charge on the Lithium battery from where the stock converter left off.

Brian

Brian,

If he wants to rely on a lithium capable solar controller to provide a balance charge he can do this. It would be best however to have all the equipment to be capable to charge lithium.
The main reason is where each enters bulk mode which most likely will be different based on each battery chemistry. So while this method will proved a balance charge (when the sun is shining) the lead acid converter may enter bulk at a lower voltage with a lithium battery. So the top balance can work, but the bottom voltage could drop below 20% SOC for the lithium (when the sun is not shining) which IMO is the cut off point for a lithium battery to aid in longevity.

I hope this answers the question.

Jim

[On The Fly]

I'm a little late coming into this discussion. I have the 165w Furrion and 50amp charge controller. I've noticed that the factory solar will keep the Battle Born charged to 13.4-13.5v without a problem. But I question the ability of the 165w PV to balance the batteries with 14.4v.
David, have you ever seen a SOC on your lithium batteries that meets the 14.4 requirement? Or is balancing the cells just a Battle Born requirement, that for me can only be met with the WFCO lithium upgrade.

Thanks

[Scott'n'Wendy]

Or is balancing the cells just a Battle Born requirement, that for me can only be met with the WFCO lithium upgrade.

Thanks

I'm not sure the WFCO LIS converter is a good choice. According to WFCO literature, the converter will only go into 14.4v-bulk mode by the output of the converter going into current limit. So with a 9855lis charger, this means it will go into bulk mode only if you exceed the 55amp rated output current.
WFCO say a discharged battery will cause the charger to hit current limit, which is true, but you don't want your battery to be discharged to that state to trigger bulk. They say intelligent charging but I'm not so sure.
Maybe I misunderstand their specs, but If you are considering the WFCO, I would call and talk to their tech support.

[On The Fly]

My 303RLS had been sitting for a couple weeks solar only, and the SOC was around 13.4-13.5v. I connected my little 2200I Honda to the shore cable and the shunt readings immediately moved to 14.4 volts. Initially the WFCO was charging at over 30amps. At approximately 15 minutes of charge time the amps had decreased to 10 but the voltage remained at 14.4
When I finished working on the trailer and disconnected the Honda, my SOC was 14.3 on both the shunt and one control panel.
I would have to assume that the WFCO was performing as advertised. But only time will tell. One event does not represent a controlled test.

[bandityo]

On the Fly, ...I have not installed the Lithium battery yet, I was asking a general theory question to see if the onboard solar charge controller could top off the Lithium (if its set to lithium) once the onboard converter stops since it did not have a lithium setting.

Trying to find a more cost effective way to switch to lithium instead of having to change out the converter by having the solor (on lithium) top the battery off to 14 after onboard stops.

david

[On The Fly]

David, sorry to take so long getting back to you. I just missed your post.
Anyway, five sunny days with the battery switch and refrigerator off and the furrion solar controller never pushed my batteries beyond a 13.4v sate of charge. Needed to connect to generator to achieve 14.4v

Bill

[Guest]

David, sorry to take so long getting back to you. I just missed your post.
Anyway, five sunny days with the battery switch and refrigerator off and the furrion solar controller never pushed my batteries beyond a 13.4v sate of charge. Needed to connect to generator to achieve 14.4v

Bill

Bill,

This is a good datapoint. Wondering would it have been possible for your solar charger to have reached 14.4 during charging and the parasitic loads on the rig reduced the overall voltage once the solar charger finished its routine? Looking at the LiFeP04 charge profile and wondering if the solar charger may have hit the higher voltage point to balance the battery. If not, your confirming a dedicated converter would be helpful.

Jim