LiFePO4 vs. Dual AGM

[Gorunhannah]

Hey All!

I am new to the app and am looking for some guidance. I am getting ready to go with an auxiliary battery system to power my fridge, lights, etc. I also have set up my jeep wrangler so my family sleeps in it. With that in mind I went to a shop about getting some assistance with the build (originally thinking LiFePO4) and the techs recommended a dual AGM set up for safety since we sleep in the jeep. So, is the LiFePO with a management system like RedArc not safe? Would AGM be the best option? Thoughts?

 

[Wanderlost]

I can't imagine why they think the lithium would not be safe. Were you thinking about mounting the LiFePO4 under the hood?

 

[Gorunhannah]

I can't imagine why they think the lithium would not be safe. Were you thinking about mounting the LiFePO4 under the hood?

No, in the cab, in the cargo compartment in the back.

 

[smritte]

Go lithium. Your LiFePO4 battery's are very stable and lighter. Compared to AGM, the benefits are too numerous to list. If you were talking high output batteries for a winch, your better off cost wise with the AGM. The correct high amp lithium is very expensive.
The problem with the guy who advised you against it is, how much actual knowledge does he have regarding batteries? In the auto world, we use L/A not AGM and certainly not lithium, so the only experience as a tech will be what he learned on his own.

The down side to any battery inside the vehicle is how much space it takes up. If you went with a non lithium, you will want to put the battery in a box and vent it properly. That just increased the size. My axillary battery is an AGM and is under the hood. The reasons are, Lithium's aren't happy under the hood, it powers my winch as well as my accessories and I don't have the room in the back.

Also, be specific on what accessories your running on your axillary battery. You mentioned lights. If you mean off road lights or anything powered mostly driving, put those on your main battery. They will run primarily off the alternator. If you for some reason need the lights on with the vehicle off, run a bigger main battery. Keep your auxiliary for fridge and camping power. If you need more reserve with the vehicle off (not moving for days) add in solar.

Welcome to the "rabbit hole" we call off road vehicle building. Pull up a chair, have a carrot, open your check book and have fun. Most of the people here have been doing this a long time. Setting up your own rig and camping in it is great.

 

[reaver]

Lifepo4 batteries are perfectly safe. Mine is in the cab, sitting on a piece of plywood, and right next to my wooden fridge box. I'm not worried about it.

I would say agm is potentially less safe due to the possibility of out gassing (though that possibility is very small).

Lifepo4 would give you the same usable energy, in less space and with much less weight. Just go with Lifepo4.

 

[reaver]

Go lithium. Your LiFePO4 battery's are very stable and lighter. Compared to AGM, the benefits are too numerous to list. If you were talking high output batteries for a winch, your better off cost wise with the AGM. The correct high amp lithium is very expensive.
The problem with the guy who advised you against it is, how much actual knowledge does he have regarding batteries? In the auto world, we use L/A not AGM and certainly not lithium, so the only experience as a tech will be what he learned on his own.

The down side to any battery inside the vehicle is how much space it takes up. If you went with a non lithium, you will want to put the battery in a box and vent it properly. That just increased the size. My axillary battery is an AGM and is under the hood. The reasons are, Lithium's aren't happy under the hood, it powers my winch as well as my accessories and I don't have the room in the back.

Also, be specific on what accessories your running on your axillary battery. You mentioned lights. If you mean off road lights or anything powered mostly driving, put those on your main battery. They will run primarily off the alternator. If you for some reason need the lights on with the vehicle off, run a bigger main battery. Keep your auxiliary for fridge and camping power. If you need more reserve with the vehicle off (not moving for days) add in solar.

Welcome to the "rabbit hole" we call off road vehicle building. Pull up a chair, have a carrot, open your check book and have fun. Most of the people here have been doing this a long time. Setting up your own rig and camping in it is great.

Indeed! But.... Who uses a check book these days? I don't think I've written a check in like.... Five years? Lol.

 

[smritte]

ndeed! But.... Who uses a check book these days? I don't think I've written a check in like.... Five years? Lol.

Heh, your right. Old habit's. That goes along with calling power accessory ports, "Cigarette Lighter Plugs". Most people today have never seen a cigarette lighter.

 

[OTH Overland]

We use Lithium for our house battery, superior in all aspects in my opinion except for being unable to charge the battery below freezing. Depending on available space and the layout in your wrangler the Lithiums can be mounted in any orientation i.e. on their sides, or you can get multiple smaller batteries and wire them in paralell to equal the capacity you need. We have the Redarc Manager 30 in our JK with 100ah of lithum and it has worked flawlessly for two years. We have removed the rear seat and have the battery and all house electronics mounted where the 40% seat was with storage on the 60% side. The Redarc will recharge the battery in a couple of hours driving and as long as we move every two or three days we do not need to use any solar to keep up with demands. As we camp a lot in winter with below freezing temps, I have insulated under the battery and installed a heating pad under the battery that will come on if the temperature of the cabinet drops near or below freezing.

 

[reaver]

We use Lithium for our house battery, superior in all aspects in my opinion except for being unable to charge the battery below freezing. Depending on available space and the layout in your wrangler the Lithiums can be mounted in any orientation i.e. on their sides, or you can get multiple smaller batteries and wire them in paralell to equal the capacity you need. We have the Redarc Manager 30 in our JK with 100ah of lithum and it has worked flawlessly for two years. We have removed the rear seat and have the battery and all house electronics mounted where the 40% seat was with storage on the 60% side. The Redarc will recharge the battery in a couple of hours driving and as long as we move every two or three days we do not need to use any solar to keep up with demands. As we camp a lot in winter with below freezing temps, I have insulated under the battery and installed a heating pad under the battery that will come on if the temperature of the cabinet drops near or below freezing.

This is the way. I have two different LiFePO4 batteries. An AOLithium that I bought for use in the trailer, and a LiTime Mini. Both are 100Ah. The AOLithium has bluetooth and Low-temp cutoff. I still added a anti-freezing tank heater that was designed for use in RV's to keep the water from freezing. It's wired to a switch, and built into the battery box, allowing me to turn it on when I need to. This battery will be moved into my wife's rig in the spring. This setup was tested by placing the battery in the freezer. I turned on the heater to make sure that everything was working. My chest freezer is well below 0*F, and the battery was staying at roughly 45*F.

The LiTime has no low temp cutoff, and no bluetooth. Based on my testing for the other battery, I'm confident that taking the other heating pad that I have, and wrapping the battery with it will be more than sufficient to keep the battery well heated for camping during the Idaho winter's.

 

[oneleglance]

AGM still needs venting even though it is a "sealed" battery
Lithium is way better and I have been running 150Ah Victron in my van for 4yrs dealing with Arizona summer temps that get the interior to 149deg.

Plus a lithium battery can be recharged faster than AGM by either solar or alt.
And it can be discharged deeper than AGM which means you get way way more battery for your money.....
To equal my 150Ah Lith I would need 300-400Ah of AGM (should NOT often go below 50% on a AGM)

 

[Gorunhannah]

We use Lithium for our house battery, superior in all aspects in my opinion except for being unable to charge the battery below freezing. Depending on available space and the layout in your wrangler the Lithiums can be mounted in any orientation i.e. on their sides, or you can get multiple smaller batteries and wire them in paralell to equal the capacity you need. We have the Redarc Manager 30 in our JK with 100ah of lithum and it has worked flawlessly for two years. We have removed the rear seat and have the battery and all house electronics mounted where the 40% seat was with storage on the 60% side. The Redarc will recharge the battery in a couple of hours driving and as long as we move every two or three days we do not need to use any solar to keep up with demands. As we camp a lot in winter with below freezing temps, I have insulated under the battery and installed a heating pad under the battery that will come on if the temperature of the cabinet drops near or below freezing.

This is the way. I have two different LiFePO4 batteries. An AOLithium that I bought for use in the trailer, and a LiTime Mini. Both are 100Ah. The AOLithium has bluetooth and Low-temp cutoff. I still added a anti-freezing tank heater that was designed for use in RV's to keep the water from freezing. It's wired to a switch, and built into the battery box, allowing me to turn it on when I need to. This battery will be moved into my wife's rig in the spring. This setup was tested by placing the battery in the freezer. I turned on the heater to make sure that everything was working. My chest freezer is well below 0*F, and the battery was staying at roughly 45*F.

The LiTime has no low temp cutoff, and no bluetooth. Based on my testing for the other battery, I'm confident that taking the other heating pad that I have, and wrapping the battery with it will be more than sufficient to keep the battery well heated for camping during the Idaho winter's.

I have gotten the LiTime mini as well. I’m hoping I won’t have to worry with warmth, a big reason I’m moving toward a permanent power supply is because I’m wanting to put a Propex 2211 onto the bottom of my jeep so we can camp in the winter with no worries. It also makes to cab comfortable on the ski days so she can come and stay in the car for a bit.

 

[reaver]

I have gotten the LiTime mini as well. I’m hoping I won’t have to worry with warmth, a big reason I’m moving toward a permanent power supply is because I’m wanting to put a Propex 2211 onto the bottom of my jeep so we can camp in the winter with no worries. It also makes to cab comfortable on the ski days so she can come and stay in the car for a bit.

I'm very happy with it so far. I used a tiny battery monitor with a shunt that displays the state of charge at the back of my drawer system. We used it on the ID BDR, powering my fridge as a freezer. It worked exceptionally well.

 

[OTH Overland]

This is the way. I have two different LiFePO4 batteries. An AOLithium that I bought for use in the trailer, and a LiTime Mini. Both are 100Ah. The AOLithium has bluetooth and Low-temp cutoff. I still added a anti-freezing tank heater that was designed for use in RV's to keep the water from freezing. It's wired to a switch, and built into the battery box, allowing me to turn it on when I need to. This battery will be moved into my wife's rig in the spring. This setup was tested by placing the battery in the freezer. I turned on the heater to make sure that everything was working. My chest freezer is well below 0*F, and the battery was staying at roughly 45*F.

The LiTime has no low temp cutoff, and no bluetooth. Based on my testing for the other battery, I'm confident that taking the other heating pad that I have, and wrapping the battery with it will be more than sufficient to keep the battery well heated for camping during the Idaho winter's.

We have the LiTime also, been 2 years and no issues. Did our heat with a tank heater pad also, think it draws 25 watts max if I remember correctly, wired mine with a snap thermostat so it only comes on at low temp, but added a master switch I can turn it off if we are leaving the rig in the cold and it won't drain the battery trying to keel the battery warm. Since the battery is buried in a cabinet and sitting on insulation I have not seen the heater come on very often unless we are parked for more than an overnight

 

[reaver]

We have the LiTime also, been 2 years and no issues. Did our heat with a tank heater pad also, think it draws 25 watts max if I remember correctly, wired mine with a snap thermostat so it only comes on at low temp, but added a master switch I can turn it off if we are leaving the rig in the cold and it won't drain the battery trying to keel the battery warm. Since the battery is buried in a cabinet and sitting on insulation I have not seen the heater come on very often unless we are parked for more than an overnight

My heater has a built in thermostat. It kicks on at 37 degrees, and shuts off at 55 or so. I can look when I get home, but I believe mine is about 35W or so.

 

[K12]

Go LiFEPO4. i sleep with two 300ah batteries in the trailer and feel safer than with the 4 agms that came with it. The charging under freezing is a non issue if you grab some rv water tank heater pads and put them on there, they have a thermostat regulator to only come on at lower temps. Ive been in Sub zero temps with no problems. Can make it even easier by putting it in an insulated box. LiFePO4 is superior in every way imo.

 

[rtexpeditions]

I've given this a lot of thought lately as my current AGMs need replacing.
There's no doubt about the performance and lower weight of LiFePO4 (lithium Iron Polymer) batteries. They are also reasonably safe, but there have been some fires caused by even respectable brand LiFePO4 batteries, mainly because of failures in the inbuilt BMS.

I'm currently tending towards replacing my AGMs with new AGMs. The AGM batteries I use are all fully sealed and are housed in the back of the rig.
I am more persuaded because I plan to ship my vehicle and the shipping lines are getting stricter on Lithium batteries. Although it could be argued that the LiFePO4 batteries are safe, shipping companies are not easily educated and I'd hate to get the vehicle stranded at some intermediate port.
I also live on an island and I'm taking a bet that similar restrictions might happen on domestic shipping to the mainland at some point.

 

[Gorunhannah]

This this look about right?

 

[freak4life]

Lithium can be positioned: upside down, on its side, on its back, no problem. I have two AGM’s under the hood and two lithiums in the cab area. I use a RedArc manager 30 to control the charge. There are advantages to each type. If you’re ever going through/to Cañon City DM me if you want to see the set up I run in my 4R.

 

[reaver]

This this look about right?

This would absolutely work. I would also recommend a shunt for monitoring the state of charge on the battery as well. I use a small 100A shunt in my Xterra that was about 30 bucks. It works just as well as the more expensive renogy shunt in the trailer.

 

[Gorunhannah]

This this look about right?

This would absolutely work. I would also recommend a shunt for monitoring the state of charge on the battery as well. I use a small 100A shunt in my Xterra that was about 30 bucks. It works just as well as the more expensive renogy shunt in the trailer.

Thanks! I will grab one and add it to the build.