Replace Stock Battery & Juice Packwith Lithium?

[BigEZ17]

I’m about to pick up my 2021 alpha wolf 26L-L which has a juice pack and a stock factory battery.

Can I replace that battery with a lithium battery and my juice pack and converter will work just fine? I am looking for light weight and a more useful long lasting battery, particularly because my refrigerator is 12 V only.

This is the first upgrade I am contemplating with my solar and battery array and just wanted to be sure that I didn’t need to replace anything else, like the converter, if I simply switch to a lithium battery.

Thanks for all your great advice in advance!

[NullPtr]

You may or may not need to replace your converter depending on:
* the specific converter installed in your trailer. Some have a lithium switch.
* whether you decide to charge primarily using solar. This depends on your solar array and whether you typically camp in shady sites.

The nominal voltage for a 4s / 12v LFP battery is somewhere between 12.8 and 13.2 volts and is stable across its discharge curve. This means that a converter that is not lithium compatible will likely not go into bulk charge mode. This results in slow and incomplete (around 80%) charging. You will also lose the passive balancing that occurs at top-of-charge.

If you have sufficient, reliable solar, you may not need a lithium compatible converter though. You can just rely on solar charging. This is how I have my trailer set up: I still have the OEM, non-lithium converter, and use solar charging most of the time. If I need to charge using the generator, I have an external 25A charger I connect directly to the batteries.

[GravelRider]

Your juice pack is probably a 50 watt (maybe 100 watt?), and won't even come close to keeping up with your 12 volt refrigerator, regardless of what the salesperson may have told you (and told me). The reason I say this is that if you're relying on the stock solar to keep your battery charged, you will be left disappointed. It's simply not big enough to keep up with demand.

Personally, if I were dropping the money on lithium, I would replace the stock converter with one that definitely works with lithium, as that is what will primarily charge up your battery (assuming you stick with just the juice pack). If you do decide to head deeper down the rabbit hole and upgrade your solar to keep up with your dry camping needs, then that's a whole different story...

FWIW, I started with a 50 amp juice pack (and 12 volt fridge), which did little more than trickle charge my battery when not in use (which was quite nice, since I don't have a plug available where I store it). I first upgraded to two 12 V batteries, then up 2 6 volt batteries, then added 800 watts of solar with an MPPT charger, then upgraded to 4 6 volt batteries. I still haven't gone lithium yet, but that'll definitely be my next move, and probably will happen with the next camper.

[tomkatb]

Plan ahead. You have 50 amps of usable battery and a 0 to 13 amps of solar.

You will consume about 100 amps per day.

Figure out you style of camping.

[NullPtr]

Didn't realize juice pack was only 50W. That is only good for about 15-20 Ah per day under ideal circumstances. My 12v fridge consumes about 30-40Ah per 24 hour day, so more solar would definitely be needed.

Your whole system needs to be planned out based on:
* The type of camping you do
* Your daily Ah usage
* Your typical available solar
* The length of time per day you're willing to run your generator.
* Charging amps available from converter and/or external charger
* Your budget

Generally, less solar / charging requires a larger battery bank and LFP batteries are more expensive than solar typically. Especially if you already have a controller and just need to add panels. Not sure what the juice pack controller is capable of though.

Go Power has an online calculator that can help you get an idea of sizing:
https://gpelectric.com/calculator/

If you are taking the plunge into LFP batteries, I'd also suggest picking up a battery monitor to help understand your usage better.

[PhilFromMaine]

Originally Posted by NullPtr

You may or may not need to replace your converter depending on:
* the specific converter installed in your trailer. Some have a lithium switch.
* whether you decide to charge primarily using solar. This depends on your solar array and whether you typically camp in shady sites.

The nominal voltage for a 4s / 12v LFP battery is somewhere between 12.8 and 13.2 volts and is stable across its discharge curve. This means that a converter that is not lithium compatible will likely not go into bulk charge mode. This results in slow and incomplete (around 80%) charging. You will also lose the passive balancing that occurs at top-of-charge.

If you have sufficient, reliable solar, you may not need a lithium compatible converter though. You can just rely on solar charging. This is how I have my trailer set up: I still have the OEM, non-lithium converter, and use solar charging most of the time. If I need to charge using the generator, I have an external 25A charger I connect directly to the batteries.

Just as an aside, I have read studies that the optimal charging and discharging of LIFEPO4 batteries is 80 percent and 20 percent. Sure, you can charge to 100 % and discharge to a little shy of 0% and get your 10 years out of your Li battery, but if you treat your battery well, according to the article, it could outlive you.

[NullPtr]

Originally Posted by PhilFromMaine

Just as an aside, I have read studies that the optimal charging and discharging of LIFEPO4 batteries is 80 percent and 20 percent. Sure, you can charge to 100 % and discharge to a little shy of 0% and get your 10 years out of your Li battery, but if you treat your battery well, according to the article, it could outlive you.

That's definitely true. Although I'm pretty sure my Battleborn's will outlive me either way At my current rate of usage, I'll cycle the batteries about 30-40 times per season. With 3-5k cycle life, they'll be good for 100 years!

[ematzen]

Hi - So I have the same original question: is it bad to leave the 50w solar on all the time when you have a lithium battery installed. For instance: I store my trailer for a month or two at a time in full sun. Should I remove the lithium battery? Or should I leave it plugged in so it will trickle charge with the juice pack? I could also turn off the solar, but worry that there might be some vampire loads (perhaps just the solar controller, which seems to be before the stock battery shut-off). If I camp 10-12 times a year, does it really matter how I treat the lithium battery (as long as I don't freeze it which I won't...I live in socal).

[NullPtr]

I wouldn’t worry about it too much. It’s probably best not to leave them at full charge for months at a time but LFP batteries are much more tolerant of high voltages than other lithium chemistries. Cold temperatures (below freezing) are only a problem for charging. If it is a quality lithium battery, the BMS will not allow that anyway. High temperatures are far worse for battery life. In general though these batteries will support a huge number of cycles and will likely outlast your camper with normal use. You may want to contact your battery manufacturer to see what they recommend for storage.

[ematzen]

Cool. Thank you. So…follow-up question. We have a 12v furrion fridge. Worked fine when plugged into shore power and plugged into tow vehicle. However, now that I have the lithium we have boondocked once, and the fridge did not stay cold. Compressor was running the whole time and simply didn’t stay warm. I suspect it’s the fridge, but is it possible that the lithium battery could be causing the issue? My guess is now but I’d love thoughts. I never boondocked with the agm that came with the trailer…

As an fyi - the lithium battery ran the fridge compressor all night (without making much cold), and had juice in the morning.

E