12v lithium battery thoughts

[parmm]

I've had two Battleborn 100 ah batteries installed on my Scamp 19. Last year spent 3 nights at Assateague State Park in one of the non-electric sites. No solar or generator. I use a Cpap breathing machine. All lights are converted to led. Ran my computer on 12 vdc and charged our phones as needed. Had no problem getting thru those 3 nights! I would have never attempted that with lead acid batteries without some way of charging them during the day. Oh, have only good things to say about Battleborn. They guided me in seating up my system and were there to answer every question I called about!

[MrJohn]

Originally Posted by chrisblessing

I am in my 2nd year using a 120Ah LiFePo4 (DIY) battery. It is mounted inside the Scamp, along with the charge controller, BMS and other associated hardware. I have a small Danfoss/Secop mini-compressor refrigerator with freezer, a furnace, two mounted LED lights and several charge ports. I charge with 200 watts of solar mounted to the top of my 13' Scamp, and I carry a 120 watt suitcase panel for use in shade areas. I always boondock, and have gone 3-4 days without sun but have always had sufficient power. It seems just about the perfect setup and meets all of my needs.

@chrisblessing & @parmm

We have a 13' Scamp we want to put 100Ah into.

Did you use the same 12g/14g wire from the battery compartment back to the converter? Or did you re-run thicker guage wire?

Also, did you swap out the delivered scamp controller with the Progressive Dynamics 9130LV?

Thanks for your help!

[parmm]

I installed a new converter/charger - a Progressive Dynamics 12 V 45-amp LiFePO4 battery converter charger. and ran new wiring from it to the batteries, 8 gauge as I remember. Batteries are located in battery boxes located on towing framework in front of trailer under loft. I am also using a Victron Energy Orion-Tr Smart 12/12-Volt 30 amp 360-Watt DC-DC charger Isolated running off my tow vehicle's alternator. I am running 6 gauge wire from the truck's alternator to the charger, which is mounted inside the front of the trailer.

[Jon Vermilye]

Originally Posted by MrJohn

@chrisblessing & @parmm

We have a 13' Scamp we want to put 100Ah into.

Did you use the same 12g/14g wire from the battery compartment back to the converter? Or did you re-run thicker guage wire?

Also, did you swap out the delivered scamp controller with the Progressive Dynamics 9130LV?

Thanks for your help!

A lithium battery will draw the entire output of your converter until close to 98% filled, so the wiring between it & the converter should be sized for the maximum output of the converter. I would want larger than #14 wire even with a 35 amp converter. The larger wire will result in less voltage drop & less likely to overheat.

As to changing the converter, it is likely the original converter will not fully charge the lithium battery because it will not provide the 14.4V or so for long enough to fully charge & balance the cells in the battery. If you are comfortable charging to less than full (and many are) try the original before deciding whether you need to switch.

[parmm]

Originally Posted by Jon Vermilye

A lithium battery will draw the entire output of your converter until close to 98% filled, so the wiring between it & the converter should be sized for the maximum output of the converter. I would want larger than #14 wire even with a 35 amp converter. The larger wire will result in less voltage drop & less likely to overheat.

As to changing the converter, it is likely the original converter will not fully charge the lithium battery because it will not provide the 14.4V or so for long enough to fully charge & balance the cells in the battery. If you are comfortable charging to less than full (and many are) try the original before deciding whether you need to switch.

But remember when saying one wants larger that #14, is not saying to get #16, as it is lighter, thinner wire. From #14, larger goes down in gauge #. i.e. #8 is larger wire that #14.

[WDavidG]

Originally Posted by MrJohn

@chrisblessing & @parmm

We have a 13' Scamp we want to put 100Ah into.

Did you use the same 12g/14g wire from the battery compartment back to the converter? Or did you re-run thicker guage wire?

Also, did you swap out the delivered scamp controller with the Progressive Dynamics 9130LV?

Thanks for your help!

John,
I also installed the 100 AH LiFePO in my scamp 13. I installed it in the center under-bunk compartment (the tongue battery box now houses chocks and jack pads). I ran 6 g wiring from the TV into the scamp (I ran a separate wire w/ Anderson connector, bypassing the 7 pin). I'm using the 20 amp renogy dc - dc. Battleborn advised me that my original PD converter would work - sort of with some fussing, but I opted for replacing it with the lithium version. The victron shunt with bluetooth to your phone is well worth the cost and extra install time. In addition to basic lights, occasional fan/furnace, and charging electronics we keep an Iceco 12v compressor fridge in the scamp. We can go five or more days without needing to top up the battery with our small 100 w solar suitcase. And as an added bonus with the 6g wiring to TV, we can run the factory 3-way fridge on DC and charge the battery while driving. This install has been a game-changer for us. I think you'll also be happy with the results.

[WDavidG]

John,
Jon's reply reminds me that I failed to mention that I did, as he correctly advises, run 6g wiring between the PD converter and the battery. I also grounded the converter per the PD instruction manual, something that scamp failed to do in the original wiring.

[Darwin Maring]

Originally Posted by WDavidG

John,
Jon's reply reminds me that I failed to mention that I did, as he correctly advises, run 6g wiring between the PD converter and the battery. I also grounded the converter per the PD instruction manual, something that scamp failed to do in the original wiring.

Scamp Quality

[MrJohn]

@Parmm & @WDavidG & @JohnVermilye - Wow! Really great advice - this is awesome to get all this information from people that actually did it already! Thank you for the advice.

Thanks for confirming the wire size needs to be increased (smaller number).
I can run some white and black 6g/8g wires from the battery box (on the tongue) back to the new PD9130LV. Battleborn told me my original Converter would work, but after some research, I now know the original converter will not work. The correct converter, PD9130LV is exactly the same size and should be a drop-in replacement. I will measure to see if the PD9145ALV can fit into the same place - using the same screw holes to secure it to the floor.


1) We have not taken the wire bundle that runs from front to back apart, but on first look, it seems the existing 12g white and black wires from the battery to the converter have taps on them before they reach the power converter. It is one continuous wire from battery to the converter, right? The wires for brake and lights come from the distribution panel/fuses, correct?


2) This is great advice that we should run a thicker wire from the tow vehicle to the Lithium camper battery. A good idea to have some quick connectors to make this easier. Just have to figure out a place to tuck the wires We did not know that. If we wanted to add this as a Phase 2 project, is there anything we should do differently with connections from the 7-pin tow vehicle connector?


3) Any advice on the best way to re-seal the hole at the front where the wire bundle comes into the camper after this is opened up for these new wires?


4) @WDavidG - Good idea to correct a wiring shortcoming. How did you ground the converter?

Thank you all again for the awesome insight!

[Raspy]

Originally Posted by MrJohn

2) This is great advice that we should run a thicker wire from the tow vehicle to the Lithium camper battery. A good idea to have some quick connectors to make this easier. Just have to figure out a place to tuck the wires We did not know that. If we wanted to add this as a Phase 2 project, is there anything we should do differently with connections from the 7-pin tow vehicle connector?


3) Any advice on the best way to re-seal the hole at the front where the wire bundle comes into the camper after this is opened up for these new wires?

John,

If I'm not mistaken, you have two separate charging projects here. One, as you describe is charging your lithium from the new PD converter, and you seem to have that handled.
The second is running a higher amp set of wires from the tow, to charge while driving. The best way to do this second system is run another set of wires, independent of the seven pin wiring, from the tow battery to the trailer. Connect these at the tongue with an Anderson plug, which you would plug in when hitching up and connecting the seven pin. This second set of wires will provide much higher amperage than the seven pin charging wire does. However, with lithium, you should not connect the wires directly to the trailer battery. Instead, install a dc-dc charger to manage this charging job. A Victron Orion 30 amp charger is an excellent choice for this. It has blue tooth and it senses the rise/fall in voltage when the tow is started/stopped, to turn on or off. No switching or third wire required. #6 wires from the tow would be good, running through an Anderson plug, connected directly to the Orion, which is connected directly to the house battery. That's it.

As Jon mentioned, the original PD charger will not properly top off the lithiums, but if you install the Orion, or solar with a lithium MPPT controller, it will make up the difference and work fine. That is what I did on a lithium conversion I did on an Oliver. We used the solar to top off the lithium house batts. Now, three years into it, the system has worked flawlessly. I think it is better to replace the PD, but not necessary if you have solar or regularly use the tow to charge with a dc-dc charger. If you go with solar, use a Victron solar controller that can "talk" to your Orion and avoid conflicting with it. The problem I have with my system is that I'm using a Gopower MPPT solar controller and an Orion dc-dc charger. When both are charging, they see the voltage from the other and go into float, because they cannot communicate.

For passing the wires through the hull, you can find a nice bulkhead fitting for strain relief, and seal the wires with Dicor.

[WDavidG]

Originally Posted by MrJohn

@Parmm & @WDavidG & @JohnVermilye

4) @WDavidG - Good idea to correct a wiring shortcoming. How did you ground the converter?

I just ran a 6 awg wire (PD specs anything between 6 and 12 awg) from the grounding lug on the PD, down through the floor (drill hole for a snug fit and seal) and used a self threading screw to connect it to the frame. Clean the frame to bare metal at the point of connection to assure good conductivity. I put ring terminals on both ends of the wire but you could get by without them.

[MrJohn]

@raspy & @WDavidG - thank you for the great input.

Very helpful advice on Dicor and Orion.

Just a quick Amazon search on Orion showed what you mentioned.

It also showed some DC-DC chargers with MPPT built in. Haven't done enough research to see if this is viable, but it would be fewer connections.


Thank you all again!

[Raspy]

Originally Posted by MrJohn

@raspy & @WDavidG - thank you for the great input.

Very helpful advice on Dicor and Orion.

Just a quick Amazon search on Orion showed what you mentioned.

It also showed some DC-DC chargers with MPPT built in. Haven't done enough research to see if this is viable, but it would be fewer connections.


Thank you all again!

John,

If you'd like to talk to an expert about Orion, call Bend Battery in Bend Oregon.
That is where I got my Orion and they were very helpful. I think you will be looking for the "isolated" model.

[John in Santa Cruz]

mainly,. the Orion 12/12-18 is only available as an isolated model. it doesnt' care if the two negatives are tied together somewhere. If you opt for the 12V/12V 30A model, thats available isolated or non-isolated, but be aware that if there's a couple volts of drop it might try to pull 40 or 50 amps from your vehicle to maintain the output voltage, and at those kinds of currents, the voltage drops are even higher.

[Jane P.]

The gage used is important - worth extra cost. I used 8 gage between the rooftop solar panels and solar controller and 4 gage between the controller and lithium battery.

The quality of the wiring is equally important. Be sure to purchase high-quality copy wire. Avoid less expensive copper clad aluminum.

[Jane P.]

Originally Posted by MrJohn

@raspy & @WDavidG - thank you for the great input.

Very helpful advice on Dicor and Orion.

Just a quick Amazon search on Orion showed what you mentioned.

It also showed some DC-DC chargers with MPPT built in. Haven't done enough research to see if this is viable, but it would be fewer connections.


Thank you all again!

I believe you cannot wire your solar panels in parallel if you use a DC-DC charger with MPPT built-in.

But the technology is changing and expanding all the time.

[John in Santa Cruz]

a DC DC charger *is* a form of MPPT device, but are you saying someone makes a DC DC thats also a solar charger ?

re MPPT controllers, the one I got for my solar panels can take up to 100V of max PV, so two ~40 volt PV panels like the one I have could be run in series, OR in parallel. Except I think I'd exceed this controller's power ratings, which is max 440W PV (my panel is 360W)... I'd have to upgrade to the 100/50.

[Raspy]

With the panels sitting flat on the roof, at our approximate latitude, you are unlikely to see more than about 60% of the rated output. 55% might be more realistic.

My 30 amp GoPower MPPT solar controller is rated to put out 30 amps, but I don't know how much it can receive from the solar without damage

In my case, I have 660 watts of solar collectors. 60% of that, at 13.8 volts, is 28.7 amps. I assume that if I exceed that 60% number, or go above 660 watts of collectors, the controller will still only charge at 30 amps max. So the only advantage to more solar would be in worse weather or in off-peak hours. And I don't know how much I can feed the controller before hurting it.

Thoughts?

[John in Santa Cruz]

i was getting 300W out of my 360W flat mount panel in february at 37N. newer panels are much more efficient than even the panels of just a few years ago. Mine is a LG Neon-R 360, monocrystalline, 40-44V PV open circuit, 36V typical at max output, fed into a Victron SmartSolar MPPT 100/30.

when I was out in the open, I got as much as 2000 WH/day. most typical camping days it only takes 600-800 WH to fully keep my trailer happy and batteries 100% charged by noon.

[Raspy]

Jon,

That's remarkable performance. I get that the newer panels are getting more efficient, but it seems there must be more to the story. Maybe your panels are very conservatively rated? As the apparent aperture reduces, as the sun angle moves away from normal, there is just less power available. But, of course, the first few degrees of misalignment only makes a small difference. Are panels only rated at the theoretical max, or more of a practical average? I'm finding too, that where I live, at 4,900 ft, collectors way outperform what they will do in the Bay Area. Meaning that even the seemingly clear atmosphere restricts performance.