best AGM 94R H7 vs. LiFePo lithium 97R H7 as a starter/main/only battery?

[STW]

What are the pros and cons of using one as the main starter battery compared to the best quality AGM 94R H7 battery?
(as main/only battery with OEM Aux disconnected)

I've noticed a few here are using a LiFePo battery as a main starting battery.
I thought there were charging differences for LiFePo batteries that made them incompatible with (non-modified) alternator charging systems, but this one is advertised as a direct replacement:
https://www.amazon.com/Powertex-Bat...14&sprefix=lipo+battery+94r+h7,aps,120&sr=8-1

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[Heimkehr]

A lithium vehicle battery of good quality should outperform a traditional lead acid/AGM battery in most metrics. The former does require the proper care, though. E.g., not allowing it to over-discharge if the vehicle isn't being driven for extended periods, and especially using a maintenance charger that is designed for and thus compatible with the lithium chemistry.

Resist the temptation to install a smaller lithium battery simply because it has the ability to crank the engine. You'll want to use a battery of similar size to the AGM equivalent. The vehicle's charging system may have a rate of charge that an undersized lithium battery can't safely handle in the manner that a properly sized battery will be able to do.

Know also that any Battery Management System built into a lithium battery isn't a panacea. The BMS will offer a limited degree of protection from over-discharge, over-charge, and will balance the cells of the Lithium Battery Cells inside your Battery. However, it will not correct or refine the charge provided by the vehicle's charging system. If it is determined to be overcharging the battery, the BMS won't necessarily help you here. The fault will need to be independently identified and fixed.

The Achille's Heel of lithium batteries are low temperature trends. Bear this in mind if your little corner of Utah will stress a lithium battery in this manner.

I use and recommend AGM batteries for our Jeeps. Lithium batteries have, in my view, a better and safer use case in/for motorcycles and handheld jump starters.

 

[Old Jeeper]

What are the pros and cons of using one as the main starter battery compared to the best quality AGM 94R H7 battery?
(as main/only battery with OEM Aux disconnected)

I've noticed a few here are using a LiFePo battery as a main starting battery.
I thought there were charging differences for LiFePo batteries that made them incompatible with (non-modified) alternator charging systems, but this one is advertised as a direct replacement:
https://www.amazon.com/Powertex-Batteries-Lithium-Ion-LiFePO4-Automotive/dp/B09HN68DC7/ref=sr_1_1?crid=3MYBD1W7TG1ZU&keywords=lipo+battery+94R+H7&qid=1676998314&sprefix=lipo+battery+94r+h7,aps,120&sr=8-1

NOT just any LiPo, but this company IMO has it nailed:

https://antigravitybatteries.com/

 

[jaymz]

There’s plenty of pros and cons. My biggest concerns are “will the Jeep keep it charged properly”? I know that the charging system is capable, I just don’t know if it will.

Another concern is cost. I replaced both batteries on my ‘18 a little over a year ago. Mostly preventative as I bought it used and didn’t know the history. My cost for a battery is just over $100. A quality lithium battery is gonna be $650+. That’s equivalent to at least 5 AGM batteries that will last a very minimum of 3 years each. 15 years to break even? That’s a helluva a long time, and assumes that the lithium will really last than long.

 

[STW]

A lithium vehicle battery of good quality should outperform a traditional lead acid/AGM battery in most metrics. The former does require the proper care, though. E.g., not allowing it to over-discharge if the vehicle isn't being driven for extended periods, and especially using a maintenance charger that is designed for and thus compatible with the lithium chemistry.

Resist the temptation to install a smaller lithium battery simply because it has the ability to crank the engine. You'll want to use a battery of similar size to the AGM equivalent. The vehicle's charging system may have a rate of charge that an undersized lithium battery can't safely handle in the manner that a properly sized battery will be able to do.

Know also that any Battery Management System built into a lithium battery isn't a panacea. The BMS will offer a limited degree of protection from over-discharge, over-charge, and will balance the cells of the Lithium Battery Cells inside your Battery. However, it will not correct or refine the charge provided by the vehicle's charging system. If it is determined to be overcharging the battery, the BMS won't necessarily help you here. The fault will need to be independently identified and fixed...

Makes sense. You'd be depending on the lithium battery's BMS to accommodate an alternator charging system not designed for lithium batteries. Maybe that's fully worked out by companies like AntiGravity or even this Powertex battery I linked to in my original post.

This alone suggests going with the best engineered solution for vehicle battery replacement, perhaps AntiGravity. That makes the cost difference a lot greater, which means you need to to provide more significant advantages to justify that cost. I had noticed the price on the Powertex I linked was getting down nearer to the cost of a premium AMG battery so might be worth experimenting.

An advantage of staying with the AGM is that it's not an experiment. It's known.

...The Achille's Heel of lithium batteries are low temperature trends. Bear this in mind if your little corner of Utah will stress a lithium battery in this manner.

I use and recommend AGM batteries for our Jeeps. Lithium batteries have, in my view, a better and safer use case in/for motorcycles and handheld jump starters.

Had about a month this winter that didn't go above 20 degrees F (-7 C) and another month that didn't rise above 28 degrees. Unheated garage, so likely it's enough to affect a battery that's sensitive to cold.

I read comments concerned about heat too, in another thread here from folks knowledge about lithium as main batteries--that there can be longevity reduction from the punishment batteries endure in the heat environment under the hood.

Not that lithium batteries can't manage it, apparently, but that it affects how long they can last.

Heat affects AGM batteries to, but all our data and expectations about AGM batteries assume the high heat under the hood environment. Whereas LiFePo batteries are more newly introduced to that application and their performance there might not be as well studied.

 

[Deleted member 59498]

Price doesn't make it worth it in my opinion. Could replace several batteries for the cost of one of the lithium batteries. Would lithium be more dangerous?

 

[STW]

...The Achille's Heel of lithium batteries are low temperature trends...

another comment on low temperature performance. I've noticed that LA and AGM batteries always list CCA, cold cranking amps, but AntiGravity battery info lists CA cranking amps, not CCA. At least I didn't find it on their pages yet.

Google tells me that CCA cold cranking amp is measured at -17.8 degrees Celsius (zero degrees F) and cranking amp is measured at 0 degrees Celsius (32 degrees F).

The 94R H7 Powertex I linked above lists 590 CCA and 1250 CA. I wonder if the CCA is usually about 47% of CA for most LiFePo batteries? or just this one?

Odyssey AGM 94R H7 battery shows a 840 CCA vs 1200 CA for a 70% CCA/CA ratio, so maybe this is how to quantify a LiFePo battery's sensitivity to cold compared to an AGM. If true, it would suggest a good AGM has about 50% more extreme cold performance than a comparable LiFePo.

https://www.odysseybattery.com/products/odp-agm94r-h7-l4-battery-94r-850/
btw, this Odyssey page lists MCA and HCA as well as CCA. Apparently MCA is the same as CA (measured at zero C/32F) and HCA is measured at 26.7C/80F.

 

[nU7OuxIx]

What are you trying to solve by using a LiFePO4 battery?

I'm not an expert, but I have read a lot. What I learned is lead and AGM batteries are best for cars that take a high peak load when starting. LiFePO4 batteries are best for long slower loads that are going to fully drain a battery.

Also add in the price for a LiFePO4 battery and the fact that it doesn't like cold weather. Each have their use cases but I'd stick with AGM/Lead for starting vehicles and LiFePO4 for overlanding/camping.

 

[Heimkehr]

another comment on low temperature performance.

Odyssey AGM 94R H7 battery shows a 840 CCA vs 1200 CA for a 70% CCA/CA ratio, so maybe this is how to quantify a LiFePo battery's sensitivity to cold compared to an AGM. If true, it would suggest a good AGM has about 50% more extreme cold performance than a comparable LiFePo.

By way of example, lithium batteries are popular in the motorcycling community due to their smaller footprint and significantly lighter weight. Some are even designed with a second set of terminals to accommodate safely powering accessories, and/or an internal jump-starting feature.

The trade-off of said conveniences is the lithium chemistry's compromised performance in low temperatures, as you recognize. The recommended method for waking up a lithium battery in such circumstances, so that it can properly crank the engine, is to turn on the headlight(s) for ~5 minutes. Intentionally creating a parasitic drain seems counterintuitive, but it's also a proven method to avail one's self of the battery's performance potential.

The foregoing might be fine for a motorcycle, but I wouldn't want to count on this M.O. as it concerns a modern automobile encumbered with an order of magnitude more electronics, etc. than is even a well-appointed touring bike.

I still believe the AGM is the Win for our Jeeps.

 

[STW]

What are you trying to solve by using a LiFePO4 battery?

Why the ceaseless quest to modify the hell out of every Jeep nook and cranny, of course.

but seriously, over the weekend I discovered neither my (13 month old) main battery nor Aux battery would hold a charge. Disconnected the Aux battery so I could test and charge them separately, and the Noco 10 kept giving an error message, each battery showing it could not take or hold a charge. Noco 10's Repair desulfator function eventually brought both back to a chargeable state, to my surprise.

Was initially thinking I'd need a new main battery right away, but now I have some time to learn more. I'm assuming my main battery is damaged, at least somewhat, from repeated discharges that left it unable to hold a charge. I don't know how much its life was reduced, but I'm thinking I should start learning what to do to protect it better:

1) from my reading I've decided to keep the Aux disconnected, not use ESS; I removed F42 fuse and no longer trust the dual battery system that lets two batteries cannibalize each other. No doubt it works for some but I don't trust Jeep's way of applying their ESS. And it looks like it's not something your dealer wants to help you fix under warranty.
2) from my reading I learned I should be using the battery charger daily if possible to keep the battery charged up. I don't drive it daily and lately trips have been short trips, so that's doesn't charge the batteries enough. I haven't seen the "ESS ready" notification for months. Now I understand that was a warning I should have heeded earlier. My TJ didn't need that kind of attention for 22 years, but it didn't have the electronics either.
3) from my reading I noticed their are more options for batteries now, and I don't know enough. I use a LiFePo battery for fridge and other camping stuff, but didn't realize there were LiFePo starter battery / main battery applications too. So I'm learning.

I'm not an expert, but I have read a lot. What I learned is lead and AGM batteries are best for cars that take a high peak load when starting. LiFePO4 batteries are best for long slower loads that are going to fully drain a battery.

Also add in the price for a LiFePO4 battery and the fact that it doesn't like cold weather. Each have their use cases but I'd stick with AGM/Lead for starting vehicles and LiFePO4 for overlanding/camping.

Price and cold starts are a strong argument for AGM

 

[nU7OuxIx]

but seriously, over the weekend I discovered neither my (13 month old) main battery nor Aux battery would hold a charge. Disconnected the Aux battery so I could test and charge them separately, and the Noco 10 kept giving an error message, each battery showing it could not take or hold a charge. Noco 10's Repair desulfator function eventually brought both back to a chargeable state, to my surprise.

If a battery dies in 13 months then there's probably something wrong with the battery. I would hope the battery would be under warranty. During covid I bought a new battery for my other car and it died within about 13 months actually. Brought it into autozone and they said that one of the cells was bad and replaced it free of charge. More on this though in a minute.

2) from my reading I learned I should be using the battery charger daily if possible to keep the battery charged up. I don't drive it daily and lately trips have been short trips, so that's doesn't charge the batteries enough. I haven't seen the "ESS ready" notification for months. Now I understand that was a warning I should have heeded earlier. My TJ didn't need that kind of attention for 22 years, but it didn't have the electronics either.

This is funny... As mentioned above, during covid I had to replace a battery in my 2016 Subaru. The battery was about 3 years old so I knew it was about time anyways. I replaced it and about a year later, it was dead again. We drove it maybe once a week, if that, during covid. Autozone replaced it and I put a noco charger on it after that. So far, it's been fine.

For my jeep, I drive it about 3 times a week and it's been good, but I've been mostly using a noco charger on it when I don't drive it. So far that's been fine.

I also have a YJ and it sat in the garage for a year while I rebuilt it and it started right up. I let it sit for months during the winter and the battery was fine starting back up. I replaced the battery last year and have since had a noco charger on it just for kicks.

So from my experience, it feels like the newer vehicles kill the batteries quicker than older vehicles. And if you're driving the jeep once or twice a week, I would put a noco charger on it.

3) from my reading I noticed their are more options for batteries now, and I don't know enough. I use a LiFePo battery for fridge and other camping stuff, but didn't realize there were LiFePo starter battery / main battery applications too. So I'm learning.

I do the same; use LiFePO4 for overlanding/camping/fridge but use an AGM or Lead for the vehicles. I didn't even know they had starter LiFePO4 batteries out there until you mentioned it. I would stick with the current configuration. But if you want to do something, you can replace the batteries with the Genesis system using AGM batteries and just keep a noco charger on it when not in use. It's a pain to plug it and unplug it everytime, but you can run the wire to the bumper or somewhere else just to make it easier.

 

[jessedacri]

I spoke with support for Dakota Lithium and they advised me to stay away from a LiFePo4 starter battery due to my winch. I have a Warn VR EVO 10S with 358A peak draw, what I thought was a pretty middle of the road winch, but that seems to be too much for the battery for them to recommend, citing the specs of their battery as 200A max continuous, 300A max 10-second pulse, 1,000A max 2-sec CCA pulse.

I feel like it's quite close to the limit and I definitely don't want to toe the line of what's recommended and/or covered under their warranty with something volatile like a battery. I guess Odyssey it is for me.

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