Has anyone tried running a lithium battery under the hood in their 2025+?

[Georgf]

Hi all. So if I replace AGM battery for LTO what capacity i should install, and will OEM charging system works with no problem? Thinking about this

 

[boogielander]

Hi all. So if I replace AGM battery for LTO what capacity i should install, and will OEM charging system works with no problem? Thinking about this

you want to replace the starting AGM battery for LTO? or you want to use LTO as a secondary battery to power whatever things you need when your engine's not running?

If it's the first, you'll run into issues previously discussed.
If it's the second, you should add a DC-DC charger (MPPT optional but recommended so you can trickle charge your starting battery with solar)

Options for DC-DC Charger:

• Victron Orion Smart 12/12-18A DC-DC charger isolated
• Victron Orion Smart 12/24-15A DC-DC charger isolated

Both options have built in disconnect so they will stop charging with ignition off to preserve your starting battery and have built in charging profiles

Option for DC-DC Charger w/ MPPT:

• Redarc Alpha50

This is the best, though pricy, option, but it has built in bluetooth module, small package footprint, and built in smarter charging logic to help you preserve your battery. Also has the "self-recovery" function where it uses your LTO battery to charge your starting battery so you can start the truck. It is also designed and made in Australia.

Some people swear by Renogy. Yes, it is much cheaper but I do NOT have good experience with it in terms of long-term reliability: longest it survived was... 1 year. It is designed in California but made in China, so there's also that.

 

[jimothy]

you want to replace the starting AGM battery for LTO? or you want to use LTO as a secondary battery to power whatever things you need when your engine's not running?

If it's the first, you'll run into issues previously discussed.
If it's the second, you should add a DC-DC charger (MPPT optional but recommended so you can trickle charge your starting battery with solar)

Options for DC-DC Charger:

• Victron Orion Smart 12/12-18A DC-DC charger isolated
• Victron Orion Smart 12/24-15A DC-DC charger isolated

Both options have built in disconnect so they will stop charging with ignition off to preserve your starting battery and have built in charging profiles

Option for DC-DC Charger w/ MPPT:

• Redarc Alpha50

This is the best, though pricy, option, but it has built in bluetooth module, small package footprint, and built in smarter charging logic to help you preserve your battery. Also has the "self-recovery" function where it uses your LTO battery to charge your starting battery so you can start the truck. It is also designed and made in Australia.

Some people swear by Renogy. Yes, it is much cheaper but I do NOT have good experience with it in terms of long-term reliability: longest it survived was... 1 year. It is designed in California but made in China, so there's also that.

Good suggestions, but I’d substitute the newer Orion XS for the two older models you suggested. More efficient, lower heat, and smaller, so easier to find a place for it.

Edit: on the other hand, the XS is not isolated.

 

[boogielander]

Good suggestions, but I’d substitute the newer Orion XS for the two older models you suggested. More efficient, lower heat, and smaller, so easier to find a place for it.

Edit: on the other hand, the XS is not isolated.

oh yes. didn't know they came up with the XS.
my Tr just refuse to die even with the breaker tripping issues I had. Turned out one of the cables had bad crimp and that combined with the TR's 15A output at 22V heated up the cable to the point it tripped the breaker repeatedly.

if my TR dies I'll swap for a XS... just don't know when LOL
being non-isolated doesn't really matter because I have a power distribution block with ground inside the cab where all these are wired to, including the ground.

 

[jimothy]

oh yes. didn't know they came up with the XS.
my Tr just refuse to die even with the breaker tripping issues I had. Turned out one of the cables had bad crimp and that combined with the TR's 15A output at 22V heated up the cable to the point it tripped the breaker repeatedly.

if my TR dies I'll swap for a XS... just don't know when LOL
being non-isolated doesn't really matter because I have a power distribution block with ground inside the cab where all these are wired to, including the ground.

Yep, if you’re sharing a ground, you’ve already made your aux battery non-isolated anyway. But for now, if it ain’t broke, don’t fix it.

 

[boogielander]

Yep, if you’re sharing a ground, you’ve already made your aux battery non-isolated anyway. But for now, if it ain’t broke, don’t fix it.

yeap
well i do have a second Victron 12/24-15A that my friend took off from his truck. long story short his XT-60i cable for his Ecoflow Delta 2 Max malfunctioned and wasn't charging (fried one of the Max's ports) and shorted his Victron. He thought Victron was the problem so he swapped my old 12/12-18A in and later found out it's the XT-60i. RMA the Delta 2 Max and saved his 12/24-15A for spare.
When I had my breaker randomly tripping on my 12/24-15A, I swapped his in because I thought my Victron was going out. Turned out it wasn't. So... now I got a spare 12/24-15A LOL

 

[Maverik259]

Saw a guy with an optima orange top on the Facebook groups today without issue so it seems it can be done.


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[boogielander]

Saw a guy with an optima orange top on the Facebook groups today without issue so it seems it can be done.


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again, it can be done if the truck is not ETorque, if it's eTorque then he will kill the battery because how the truck's electrical system is designed.

 

[jimothy]

again, it can be done if the truck is not ETorque, if it's eTorque then he will kill the battery because how the truck's electrical system is designed.

I don’t think that’s true at all. April will mark two years that I’ve been running a LiFePO4 battery under my hood (5.7L ETorque), and it’s not dead yet.

The problem with ETorque is it under charges my lithium starter battery, which is actually better for longevity. If anything kills my battery, it’s going to be heat, which is going to be an issue regardless of powertrain.

I haven’t done a capacity test of my battery to see how much it has diminished since I installed it, but I would attribute most of any capacity loss to heat. The rest of any loss would be attributed to use, which is mostly independent of ETorque.

So no, ETorque will not kill a lithium starter battery.

 

[jimothy]

I don’t think that’s true at all. April will mark two years that I’ve been running a LiFePO4 battery under my hood (5.7L ETorque), and it’s not dead yet.

The problem with ETorque is it under charges my lithium starter battery, which is actually better for longevity. If anything kills my battery, it’s going to be heat, which is going to be an issue regardless of powertrain.

I haven’t done a capacity test of my battery to see how much it has diminished since I installed it, but I would attribute most of any capacity loss to heat. The rest of any loss would be attributed to use, which is mostly independent of ETorque.

So no, ETorque will not kill a lithium starter battery.

Let me take back a little of what I said: I do see high amperage when charging (60-80A typically, and I’ve seen it reach as high as 100A). That does have an impact on battery longevity, and may be related to ETorque.

Limiting charge rate to 25A would be better for longevity. My hunch is that a non-ETorque alternator would charge the battery more continuously but at a lower current, while ETorque results in it being charged for 5-10 minutes at a time at a high rate.

If that’s correct, then ETorque may age by starter battery more rapidly than non-ETorque. But the opposite could also be true: non ETorque will charge at a higher voltage, and since charge current is proportional to the difference between charge voltage and battery voltage, it might charge at an even higher current. (The highest charge voltage I’ve seen is 13.8V, while 14.4V is normal for non-ETorque from what I understand)

But I still state that ETorque will not kill a lithium starter battery. 22 months in, my system is still working. I don’t have the data to say whether ETorque ages a lithium battery more or less rapidly than a non-ETorque system would.

 

[boogielander]

I don’t think that’s true at all. April will mark two years that I’ve been running a LiFePO4 battery under my hood (5.7L ETorque), and it’s not dead yet.

The problem with ETorque is it under charges my lithium starter battery, which is actually better for longevity. If anything kills my battery, it’s going to be heat, which is going to be an issue regardless of powertrain.

I haven’t done a capacity test of my battery to see how much it has diminished since I installed it, but I would attribute most of any capacity loss to heat. The rest of any loss would be attributed to use, which is mostly independent of ETorque.

So no, ETorque will not kill a lithium starter battery.

i thought he was referring to LiFEPO4 for starter battery. If he's using it as a house battery using proper DC-DC charging solution then heat will be the only issue.
and i am pretty certain that LiFEPO4 likes to be kept at certain voltage. Using the below table, since ET keeps the voltage low at times (12.5-12.6v when engine is off), you are only keeping it half charged. 50% is optimal for long term storage, but that is not what a starting battery used for. A quick Google search returned from various LiFEPO4 vendors all saying keeping it 90% charged (aka, 14.2v) is optimal.

but i do see you have no issues yet so... while i commend your bravery for messing with it but... it does remind me of when customers bring me things they broke because one guy did it with great success on internet despite many published datasheets disagreeing lol

 

[jimothy]

i thought he was referring to LiFEPO4 for starter battery. If he's using it as a house battery using proper DC-DC charging solution then heat will be the only issue.
and i am pretty certain that LiFEPO4 likes to be kept at certain voltage. Using the below table, since ET keeps the voltage low at times (12.5-12.6v when engine is off), you are only keeping it half charged. 50% is optimal for long term storage, but that is not what a starting battery used for. A quick Google search returned from various LiFEPO4 vendors all saying keeping it 90% charged (aka, 14.2v) is optimal.
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but i do see you have no issues yet so... while i commend your bravery for messing with it but... it does remind me of when customers bring me things they broke because one guy did it with great succcss on internet despite many published datasheets disagreeing lol

I am also using an LFP battery as a starter battery (dual purpose, strictly speaking, as the battery works as both a starter battery and deep cycle battery).

If I understand you correctly, you're implying that because 90% SOC (state of charge) is "optimal", and because eTorque will keep the SOC in a narrower range (say, 40-60% charged), that this is less than optimal and therefore will age the battery faster. This is, I assume, why you stated that eTorque will "kill" an LFP battery.

But it's simply not true: if all you care about is battery longevity, a narrower SOC range (how low you discharge the battery, how high you charge it) is better. Keeping a 20-80% SOC will give more cycles than 10-90%, and a really narrow range, like 40-60% (which may be close to where eTorque keeps the battery), will give even more cycles. So eTorque, far from killing the battery, is going to be gentler on the battery than non-eTorque, if non-eTorque results in a higher charge level. (Assuming all other factors are the same, especially charge and discharge current, which are more significant factors to battery aging than cycle count).

But cycle count is only one factor in aging a battery. Under the hood, heat is likely to be the biggest factor. If there's a reason not to use an LFP battery under the hood, heat is it, because temperatures will get high.

(As an aside, we shouldn't obsess about cycle count anyway. If 10-90% gives you 5,000 cycles and 20-80% gives you 6,000 cycles, either will give you more than a decade of use assuming one full cycle (equivalent of 0-100%) each day. Before you've reached either of those cycle counts, heat and time will have aged the battery more than charge-discharge cycling).

Yes, don't put replace your starter battery with an LFP just because mine hasn't failed yet. I'm not sure I'd repeat this experiment myself. But also, don't take people's claims that eTorque will "kill" an LFP unless they provide evidence or an argument supporting that claim.