Double Checking my Research

MrGneissGuy

Early last month, we purchased a 2015 T@G and spent a fair amount of time at home testing different systems and such, and I have been toying with switching to LiFePo and would appreciate some input from those with more knowledge than I. After spending some time searching through here, and elsewhere, regarding replacing the deep cycle battery with a LiFePo battery, I think I have pieced together the following.

Ideally, I would also replace the converter/charge system with one specifically designed for LiFePo batteries. However, I can just switch out the batteries with no changes to that with the following caveats:

Plugged into shore power, the battery will only charge to approximately 80%. I would need to use solar panels to bump it up to 100%.

While my 2015 T@G does have solar ports in the tongue box, it has no solar charge controller, so I'd need to get and install one of those.

And beyond that, the battery box I have will not likely be large enough for a 100ah LiFePo, so I would need a new box and would need to secure that, or go with a smaller battery.

Aside from not charging beyond 80%, does keeping the existing converter/charge system cause any damage to, or shorten the life span of, the LiFePo in any other way?

Am I missing anything important?

SueBHunny

I recently swapped out my battery for a 100ah LiFePo. I just did a straight out swap. My solar suitcase has a built-in solar charge controller. So far so good. And I was able to fit it into the tongue box. I had to install a larger battery box, but was able to get it all in on a bit of an angle. I used a block of wood in the frame that held the old battery box and connected the new box to the wood with screws. It's all jammed in there pretty tight and it's not going anywhere. I'm unplugged 95% of the time when I camp, so the swap really eases my mind about using the Norcold and the ceiling fan. It was the right call for me.

MrGGBrown

Not sure if you've seen my post. I installed a Lion Energy LiFePo battery and have had a slightly different experience that others. I suspect differences in the battery controllers (built into the batteries) are different enough that they don't all act the same way.

https://teardrop-trailers.vanillacommunity.com/discussion/1369/lion-energy-ut-1300-lifepo-battery-install#latest

I am able to get my battery to 100% on shore power most of the time, with the original non-Lithium-aware T@G built-in charge controller. There are times it won't charge fully, and I have a hypothesis it might be related to the voltage level of the electrical service, but that's really only a guess. I also have had times when the TV wouldn't fully charge it, but recently discovered the alternator was getting weak in the TV and that might have been why. My Renogy 100-watt solar suitcase always gets it to 100%, and charges at over 6 amps in full sun.

The Lion Energy battery fits in the original group 24 battery box, which eliminates the need to install a bigger box. People have commented recently that the newer Renogy batteries will also fit in the group 24 sized box.

It's an expensive upgrade for sure, but after you get past the cost, it's an awesome upgrade. You'll have so much more usable battery capacity, and so few less worries about running the battery too low. And another side benefit - no need for trickle chargers over the winter. My battery loses almost no charge over several months of sitting, even with temperatures in the 30's.

To your bottom-line question -- I can't say definitively, but I don't believe any damage is done to the battery by keeping the original charge controller. The LiFePo batteries are rated for so many charge cycles that I expect my battery is likely to outlive my trailer.

MrGneissGuy

Thank you both. Very helpful.

MrGneissGuy

Well, I've placed the order and Renogy battery, bluetooth module, and solar charge controller should be delivered tomorrow and Wednesday.

I spent some time this weekend building/attaching parts to mount the new battery in front of the tongue box, giving me more room in the tongue box for storing other things. Using an empty Group 27 battery box to test it out, it feels good and secure (I pulled and pushed and shook, etc. quite a bit and it stayed put). But I ultimately ended up getting nervous about that (and the battery manual says not to leave it in direct sunlight) and will be putting it in the tongue box. Now I have a mount for a small storage box I'll attach where I was going to put the battery.

I've pulled the old battery and done similar work in there to what others have documented. So when it gets delivered, it will be a simple drop in and connect. I'll be connecting the solar charge controller directly to my solar panels, at least initially. I'm thinking of mounting a flexible panel to the T@G top, and if I do that, I'll move the controller to the tongue box then.

I also bought a battery disconnect switch that I plan to connect as well.

zgfiredude

Nice......photos will be necessary of course.

One idea I have had for "increased" space in the tongue box is to recess the battery down partially or mostly through the floor in the box. Maybe use a battery box and drop it down as you'd at least have the thickness of the frame before anything hung low......just a thought.

JamesDow

My camping with my Renogy 100 Ah LiFePo battery is very often in desert hot summer camping. No issues regarding temp. I have no high temp concerns with my battery in a group 27 box in my front tongue box. Recharge with 100 watt Renogy suitcase.

Just got back from a five day outting in desert north of Yuma (99+ degrees) with Norcold running 31 degrees, recharging of phones, cameras, usb fans and some Fantastic Fan. Returned home with 60% on my Renogy 100 Ah LiFePo battery. After returning home and plugging into shore power for 24 hours with battery switch on and Norcold running, I am currently at 97%.

Yes my 2018 older original converter can charge lithium without any issues.

Don't worry, be happy.

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Hwy395_bum

I have the self heating Renogy, 4000ft in the Sierra's gets cold and I am too old to pull it out. This is our bugout trailer, already had to get out of town with the Airport fire in February, Part of our check list when we get home from camping to to refresh, reload, and prep.

MrGneissGuy

@zgfiredude said:
Nice......photos will be necessary of course.

>

The solar charge controller and Bluetooth module were delayed in shipment, but showed up yesterday when I was home from work with a stomach bug. I was feeling a bit better by late afternoon and went ahead and hooked it all up (I already had most of the wiring done and was just waiting on those). So here you go.

Just a couple of wood pieces to flatten out the battery mount so the larger Group 27 box has a solid surface to sit on.

The battery installed, with the disconnect switch, Bluetooth module, and solar charge controller mounted on the top of the box. I used outdoor heavy duty 3M Velcro to mount the Bluetooth module and battery disconnect, and auto strength 3M mounting tape for the solar charge controller (not enough surface for the Velcro pieces). That way they'd be easier to unmount if I need to get in there, and I don't have to worry about metal screws/bolts sticking out under the lid where the battery posts are. I did add a cable lock around it that you can see in the middle, over the strap. I know it won't keep a serious thief from stealing it. It's just intended to protect against the opportunistic thief.

A group 24 box mounted on the tongue for just a bit of extra storage. It won't hold a lot, I'll probably put my hitch lock and/or similar items in there while traveling. I'll be looking for a box of similar length and width dimensions with more height that I can place there instead to give a little more storage.

Renogy says to fully charge it before its first use, and it came in at about 63% charge. I did quickly turn on one light to test the connections and the new disconnect switch, then left the disconnect switch off and hooked up my solar panels. It was overcast most of the time I had it hooked up but I was able to get it up to about 84% in 4-5 hours. It's on the wrong side of the house to get much evening sun after I get home from work, but I figure an hour or two each night and I'll eventually have it to 100%. I'll leave the disconnect off until then.

The Renogy app with the Bluetooth module is very nice. It gives me more information than I even understand what to do with, and is significantly better than just a 12volt USB charger with a volt meter on it. I'll still need to test charging by shore power and during tow, but otherwise it's looking good.

JamesDow

Looks like your upgrade should serve you well.

A few things I did with the group 27 box with my conversion was to seal off the top vent holes with some hot glue from the inside. This was to help to avoid getting water into the box. I also have small hole in the bottom of the box for drainage in the event water does get in.

My Renogy battery monitor is on top of the battery box, I cover it with the top to a cardboard box (painted flat black). It is a sung fit and does not come off by itself. Just a diversion for prying eyes.

Adding lithium power is my most valued modification.

Hope all of your research pays off.

Enjoy!

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