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RLXXI

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Experts in the Mach-E forum (same battery) have said that a larger battery doesn't work with Ford's BMS.
It's not a larger battery per se, sure it has a few more Ah but that's the extent of it.
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mr.Magoo

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The lightning only charges the battery when it detects a low voltage and it stops charging when the battery reaches a higher voltage, it does not have an alternator running with constant current.
I suppose it depends on how generic you want to be and while you're not wrong on principal, you're definitely not correct either.

The Lightning will charge your battery when you start your truck and the battery isn't already fully charged, even if you haven't reached the 40% you mentioned earlier. It's not a sump pump 😉
 

ElectrifyingMe25

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I'm explaining, you're arguing, and no longer with me. I have extensive experience in electrical/electronics. I know what I'm talking about. Go right ahead and listen to the marketing fodder and drain your wallet if you like, makes no difference to me.
Here is a good video that explains the circumstances you face when trying to use a LiFePO4 battery in the place of a Lead acid on a vehicle that uses an alternator. I'm throwing this out there because it explains how a BMS can mess with your charging system. Of course it's different with an EV, but the charging system on an EV has the potential to generate a fault when trying to charge a LiFePO4 battery with a BMS.

Video:

Grok-3 says the charging ckt on a Lightning is so well tuned to the characteristics of an AGM battery that a LiFePO4 battery w/BMS will cause a charge fault on the Lightning when substituted. If a fault is generated, then the BMS reset proceedure must be used.

Apparently some have experienced this fault on this Fourm.

If you want to use a LiFePO4 battery, you need to purchase one like the one made by Ohmmu that uses a ckt that emulates the charge characteristics of an AGM battery.

Anyone else care to add to what I've discovered?

Has anyone discovered a cheaper LiFePO4 battery that will substitute?
 

flabrent

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At my company we switched from deep cycle marine batteries to LiFePO4 in our pool vac's. The main advantage was the weight for us. Another advantage was the LiFePO4 works like a fresh off the charger battery until it doesn't run at all. I warn the guys "don't let the volt meter get below 13.0v or you might end up going home early."
 

RLXXI

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At my company we switched from deep cycle marine batteries to LiFePO4 in our pool vac's. The main advantage was the weight for us. Another advantage was the LiFePO4 works like a fresh off the charger battery until it doesn't run at all. I warn the guys "don't let the volt meter get below 13.0v or you might end up going home early."
We run them in our fleet vans, air compressors, etc. If it's a 12v system, the lfp is an ideal replacement for sla. It's only downfall being extreme climate use, they don't like the cold so unless it's heated, it's better to stick with sla in extreme cold.
 

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RLXXI

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Here is a good video that explains the circumstances you face when trying to use a LiFePO4 battery in the place of a Lead acid on a vehicle that uses an alternator. I'm throwing this out there because it explains how a BMS can mess with your charging system. Of course it's different with an EV, but the charging system on an EV has the potential to generate a fault when trying to charge a LiFePO4 battery with a BMS.

Video:

Grok-3 says the charging ckt on a Lightning is so well tuned to the characteristics of an AGM battery that a LiFePO4 battery w/BMS will cause a charge fault on the Lightning when substituted. If a fault is generated, then the BMS reset proceedure must be used.

Apparently some have experienced this fault on this Fourm.

If you want to use a LiFePO4 battery, you need to purchase one like the one made by Ohmmu that uses a ckt that emulates the charge characteristics of an AGM battery.

Anyone else care to add to what I've discovered?

Has anyone discovered a cheaper LiFePO4 battery that will substitute?
Apparently you haven't been paying attention to what I've already posted so I'll not repeat myself again.
 

ElectrifyingMe25

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We run them in our fleet vans, air compressors, etc. If it's a 12v system, the lfp is an ideal replacement for sla. It's only downfall being extreme climate use, they don't like the cold so unless it's heated, it's better to stick with sla in extreme cold.
What brand and type of battery are you having success with? Picture?

Thanks
 

RLXXI

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What brand and type of battery are you having success with? Picture?

Thanks
Let's not hijack this thread more than has already been done. Start a new one if you desire.
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