Upconverting to group 31 lithium battery

TaG_Im_It

So I currently have a group 24 AGM battery with 80 amp hours (40 usable). I would like to upgrade to a group 31 100 amp hour lithium battery with nearly 100 amp hours usable. I know in the past users have increased their capacity using golf cart batteries but I think lithium is the future. I have asked my fabricator friend to think about an adapter that mounts within the current welded group 24 box that increases its capacity to a group 31. Height is not an issue in my T@g battery compartment. Its the length, and the angle. Would anyone else be interested in such an adapter?

LuckyJ

Wow, a lithium group 31, curious about how much they run for. I remember shopping for a groupe 31 optima yellow top, and remember that 2x24 of the same yellow top were cheapper than one 31.

So yep, what brand and how much? And do you need a specific battery charger to recharge? And can you recharge from the TV while driving?

beaky

https://www.amazon.com/Renogy-Lithium-Iron-Phosphate-Off-grid-Applications/dp/B075RST4R2?tag=outsidepursuits-20

LuckyJ

@beaky said:
https://www.amazon.com/Renogy-Lithium-Iron-Phosphate-Off-grid-Applications/dp/B075RST4R2?tag=outsidepursuits-20

Ok, size wise (reserve would probably is the large one compare to the groupe 31) at 170 amps cap. So that is 1500,00$ us or two of the small ones for 100AH for 800,00us.

Like I tought, wow!

beaky

100 ah of lithium is worth 200ah of AGM

LuckyJ

@beaky said:
100 ah of lithium is worth 200ah of AGM

Ok, so this is still 800$ of batteries and I don't want to think about exchange rate in my case for canadian $. Lol

But thanks for the info.

Chaverim

Also, check the weight difference of the batteries. When I upgraded battery, I got rid of my box, got a new box and put this battery in. I have a 1lb propane and the gas generator gets to mount on the tongue.

https://www.amazon.com/gp/product/B00S1QBRLQ/ref=oh_aui_search_asin_title?ie=UTF8&psc=1

TaG_Im_It

ok, to meet my desired requirements, I might not even have to have an adapter.

This is 100ah and lithium and works with my current solar controller... but... its out of stock.

Would double my usable amps, and be like half the weight. I have been impressed by the quality of the renogy product. Not top of the line, but might be good enough. I am pleased with the 100 watt solar panel and controller already purchased.

This battery seems to fit in group 24 by length and width... height is different but who cares as this is not the restricting dimension.

https://www.renogy.com/renogy-lithium-iron-phosphate-battery-12-volt-100ah/

beaky

lithium batteries will easily fit the T@G battery holder and simply plug into the existing system

TaG_Im_It

Ok, so I found this from my preferred brand and I purchased it yesterday. Delivery in a week or so. Looks like it has the same footprint as a group 24, just taller. Perfect. Well, we'll see. https://battlebornbatteries.com/shop/100ah-12v-gc2-lifepo4-deep-cycle-battery/

WilliamA

I hesitate to bring this up. We are all big boys and girls here. I considered putting in a lithium battery but decided I didn't need it. In the process of my investigation, I read a great deal of literature on them and just wanted to stress for those getting them to read ad much as possible about care and use. These are completely different animals than conventional lead-acid tech and the rules are different. There are lots of safety issues and it's only good sense to be aware of the different procedures. Let's not burn down any houses out there folks....Whether little ones or big ones...
With great power comes great responsibility and all that...

WilliamA

TaG_Im_It

Hey WilliamA - I got a LiFePO4 battery, not a lithium ion one. I think they are pretty safe now...

LiFePO4 (also known as Lithium Iron Phosphate) batteries are a huge improvement over lead acid in weight, capacity and shelf life. The LiFePO4 batteries are the safest type of Lithium batteries as they will not overheat, and even if punctured they will not catch on fire. The cathode material in LiFePO4 batteries is not hazardous, and so poses no negative health hazards or environmental hazards. Due to the oxygen being bonded tightly to the molecule, there is no danger of the battery erupting into flames like there is with Lithium-Ion. The chemistry is so stable that LiFePO4 batteries will accept a charge from a lead-acid configured charger. Though less energy-dense than the Lithium-Ion and Lithium Polymer, Iron and Phosphate are abundant and cheaper to extract so costs are much more reasonable. LiFePO4 life expectancy is approximately 5-7 years. - taken from batterystuff.com

WilliamA

Thanks for the info. I'd be the first to say I have more work to do in order to get up to speed on all of the Lithium battery tech. I did know that the iron Phosphate batteries are a lot more stable than the Li Ion jobs. It looks as though you've done your homework.
One of my main concerns about this sort of tech is the ability to charge and maintain the battery using the tow vehicle charging line as that's my preferred method of doing that. Some of the lithium tech batteries pretty much require a dedicated charger and special monitor that reads each individual cell, balancing them to a safe average. Granted, we're not powering computers in a Boeing 787 here but I've always found it pays to read past the first page of the brochure! In any case, I'd like to see a technology come around that peels off a hundred pounds of weight from my trailer. For me right now, the cost is prohibitive and as I've said before, my current needs (pun intended) are such that I can do just fine with my AGM group 24 deep cycle. I suspect that I will be replacing my battery this year as it's getting a bit short on cycle time but my current plan is to put the same or perhaps one size bigger (amperage-wise) back in. In any case, I'll be scouring the net for more information on Lithium Juice and will be watching to see how things out there in the real world are working. Do keep everyone up to speed on how it's going. I'd love to pore over a usage/maintenance chart put together from somebody that's actually using one, not just selling one.

WilliamA

TaG_Im_It

So it is in. I got the present today via fedex. Not the prettiest install. I tried to use all the stock components but I still have some research to do on a battery case that fits group 24 at the base, but GC2 tall. I think I am installing the battery sideways vs convention, but the great thing is the battery doesn't care.

As far as charging, well, Battle Born says anything that is designed for AGM will work. Though not perfect. I plugged my battery in tonight, ran the fridge for a complete cool down cycle to 37 degrees, and then ran my little honeywell space heater through a small inverter for about 1/2 hour out of the box. That space heater draws 10 amps on its low 125 watt setting.

Sure enough, i plugged in shore power and got the usual 13.6 volts from the converter. For bulk the preferred charging voltage of the LifePO4 is 14.4. This battery has a much flatter voltage curve than Lead Acid. There might be some voltage level that convinces the WFCO to go to bulk (web said take it to 12.2 volts to force bulk) but I wasn't prepared to take the battery that low tonight to test.

As far as the TV charging, well, the 14 or so volts I get out of the TV during a trip will do better than the converter, IMO.

Also, this battery has a BMS (battery management system) that is intended to take the hard engineering out of the process. It is supposed to be smart enough to use my existing system.

Edited for photo resizing.

Still learning.

Damien

TaG_Im_It

Edited for photo resizing.

Running the space heater.

CampHub

@TaG_Im_It Did you or are you planning to install a battery monitor like the BMV-700 by Victron? I know the LiFePo4 batteries have a very flat voltage curve right up until they are dead or when the battery management system turns it off. Voltmeter state of charge like one uses for lead acid batteries does not work with these.

The stock battery in our T@G has always been an under performer and after our last cold outing the lead acid did not do very well to keep up. Glad to hear this solution is working well.

Michael

@TaG_Im_It

I think I'm going to follow your lead on this. Can I ask you if you able to find a taller case for the battery? Also how does your wfco converter work with it?

Thanks,

TaG_Im_It

Ok friends, guess what, I gots good answers to the questions. First off, the case. Turns out the base of a GC2 battery is very similar to a group 24 battery. And when you add the appropriate case in a standard T@g hitch compartment, they both fit, um, well mostly. Because the new battery is taller, and the case is taller, one of those things that stick out on the ends of the plastic case to let wires in reaches the teardrop at a thicker radius, reducing clearance. It wouldn't go in. So I sawed it off.

I will talk about the victron 712 bluetooth model when it arrives. And I will talk about the wfco tomorrow.

Edited for photo resizing.

https://www.amazon.com/gp/product/B00316KU6E/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

Damien

TaG_Im_It

Ok friends. I'm done I think. Clean install of GC2 style lithium iron phosphate battery . New GC2 case. New box for new gadgets. Some wiring. I learned about crimping, heat shrink wrap, amps and so much more! So fun.... I still have to talk about the stock converter but I need to do some tests. The really cool part is I can monitor my power state from a second story above the garage! ![]

Edited for photo resizing.

CampHub

@TaG_Im_It Roughly 16 lbs of battery weight removed and an increase in usable Amp Hours. Very nicely done. I am sure you will have a lot of us thinking more about a LiFePo4 solution.

Michael

I've all but decided I'm going to go this direction also. The only thing that's holding me back is how the existing converter is going to work with it. I've sent an email to battleborn about the existing converter but I have not received a response back from them yet.

Scotty49

I installed a 100 Ah 12V Battle Born BB10012 LiFePO4 battery in our 2018 T@G Outback in October. We also installed a Victron 700 battery monitor with Bluetooth to monitor the state of charge and power utilization status. We used a Group 31 battery box for the installation. It fit in the Outback tub with only a little change in the angle of the box. The weight of the battery is only 31#, about half the weight of two 6V golf cart batteries and about 25% less than the Group 24 AGM we removed. Although you can use the WCFO converter to charge the batteries, Lithium batteries need a higher charging voltage to fully recharge them to 100% (14.2 V vs. 13.7 V from the WFCO). I purchased a Progressive Dynamics Inc. charger PD9100L series that I use about every 2 months to fully synchronize the battery. When out on a trip, we charge using solar (Zamp 120 W), generator (Yamaha 2000i), shore power (WFCO converter) and TV. What a difference it has made in our ability to boondock without having to depend on the generator. I believe a battery monitor, like the Victron, is important to monitor these batteries. See posts from @BrianZ on the T@B Forum. Attached are a couple of pictures of the install.

Photos removed due to size. Please see private message.

WilliamA

@Scotty49 said:
" Although you can use the WCFO converter to charge the batteries, Lithium batteries need a higher charging voltage to fully recharge them to 100% (14.2 V vs. 13.7 V from the WFCO). I purchased a Progressive Dynamics Inc. charger PD9100L series that I use about every 2 months to fully synchronize the battery. "

When I was down at my favorite RV store (Jerry's RV in Madison, Wi) I had a long conversation with one of the guys about Lithium batteries and he said the same thing. Folks are putting Li batteries in and smoking up their converters. He told me that either Lithium OR high capacity AGM batteries need a bigger converter. The Lithium batteries need a high voltage job and the big amperage AGM's should have a larger output (amperage) converter or they won't last long. Don't shoot the messenger here. That's what he said and I have no reason to doubt it. Makes perfect sense to me. You wouldn't fill a giant gas tank with a tiny fuel pump. Same principle applies....

I was at Menards yesterday and they had pallets of these guys:https://www.menards.com/main/tools-hardware/automotive/automotive-batteries/tools-hardware/automotive/automotive-batteries/tools-hardware/automotive/automotive-batteries/fvp-reg-voltedge-reg-m27-7dp-dual-purpose-marine-battery/m27-7dp/p-1508999327948-c-1516819218414.htm?tid=3847820861586828645&ipos=38
I almost picked one up but haven't had any experience with that brand...$74 bucks was hard to pass on though...
They also have group 27 size battery boxes for $8 bucks or so...
WilliamA

CampHub

@Scotty49 How did you run the cat5 wiring for the battery monitor?

Sharon_is_SAM

“He told me that either Lithium OR high capacity AGM batteries need a bigger converter. The Lithium batteries need a high voltage job and the big amperage AGM's should have a larger output (amperage) converter or they won't last long.”

@WilliamA, that is why we use a smart charger to fully charge our 150 amp AGM battery upon returning from a trip and before storage. The issue has been that the converter in the TaB may not remain at a high enough voltage for a long enough time to fill up the battery. The converter is fine for generic lead acid batteries - not so sure about the larger AGMs though.

TaG_Im_It

Hi friends again. I did some tests. First off yesterday I did a test where I drew a boatload of current, running a 125 watt internal space heater through a 150 w inverter. That's the low setting. Just to get an idea of the discharge / charge rate.

BTW - I think the "time remaining" is calculated at a 50% level for legacy sake. They should update this functionality based on battery type.

TaG_Im_It

Ok, then I plugged in the stock wfco converter to charge. 6.3 amps? really? Fair enough its plugged into 20 amp house power.

TaG_Im_It

When I woke up this am, battery level said 100%. But the wfco took kinda longer, with low amperage, than I would have expected. So this am I drained it again.

TaG_Im_It

I set up the 100w Renology suitcase and PWM charger for the AM sun. I know I have room to upgrade here.

TaG_Im_It

Took about 2 hours, but charged complete.

TaG_Im_It

Conclusion: Stock converter works just slow. Solar is fun.