Engineering Explained: Best practices tips to slow down LFP Battery degrading & extend SOH life

[RonTCat]

Watching the video for the NMC batteries makes me wonder if our MMEs' batteries would be better served by only charging up to 75% instead of 90% that the manual recommends. @Ford Motor Company Your thoughts please.

This would be a bad idea, since cell balancing only occurs above 80%.

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[Sparty]

After reviewing numerous posts, and also viewing their suggested scientific presentations on both the NiCad (other than a 5 or 6 in the eighth spot of the VIN, which signifies the extended range battery, and Li-ion (a 5 or 6 in the eighth spot of the VIN, which signifies the standard range battery), and seeing the various "do's" and "don'ts" they presented; I get a strong impression that owner's efforts should be primarily directed at not mistreating our battery, while still feeling comfortable with using charge ranges that meet our needs on a day to day basis!

What I came away with:

1) Time passage and heat are the natural agents that will inevitably, and eventually, reduce battery capacity by 20% or more.

2) Every charge to 100% capacity will cause ever so slight damage to the crystalline structure of the individual battery cells that make up the car battery. Doing so should certainly be done in anticipation of a longer trip, but not as a matter of daily routine.

3) Scientific testing shows that short hops of 40-50 miles; that discharge the battery from 60% to 40% seem to do the least damage to either type of battery. This is wholly practical if you are nearly homebound - roflmao!

4) Likewise, plugging in every night to recharge from a 50-60% charge to a target of 80-90% is to be preferred over allowing discharge to 20% over several days before a recharge back to 80-90% (due to crystalline cracking and electrolyte coating of the crystals).

5) Your stoic dedication to maximizing your battery's life to attain that 800,000 mile nirvana will likely result in a still healthy battery, as your 400-500K vehicle is hauled away to the scrap heap; due to failure of the frame, or any of various body or electronic components that end a vehicle's useful life (especially after an extended warranty times out and you are paying the full costs of repairs).

So, for our 2023 MME with its cold-weather-tolerant, extended range, NiCad battery; we will plug it in every night to recharge to 80%; but not hesitate to take it to 100% in anticipation of trips over 150 miles. The same approach would be true if it were the standard range Li-ion battery.

I see this approach akin to my changing the oil in my ICE diesel GMC Canyon only when its Info display says it is down to <10% life; and not the 3000 miles I see recommended by some owners, "if you really want that engine to last"!

Peace/Out

 

[Teslaeata]

After reviewing numerous posts, and also viewing their suggested scientific presentations on both the NiCad (other than a 5 or 6 in the eighth spot of the VIN, which signifies the extended range battery, and Li-ion (a 5 or 6 in the eighth spot of the VIN, which signifies the standard range battery), and seeing the various "do's" and "don'ts" they presented; I get a strong impression that owner's efforts should be primarily directed at not mistreating our battery, while still feeling comfortable with using charge ranges that meet our needs on a day to day basis!

What I came away with:

1) Time passage and heat are the natural agents that will inevitably, and eventually, reduce battery capacity by 20% or more.

2) Every charge to 100% capacity will cause ever so slight damage to the crystalline structure of the individual battery cells that make up the car battery. Doing so should certainly be done in anticipation of a longer trip, but not as a matter of daily routine.

3) Scientific testing shows that short hops of 40-50 miles; that discharge the battery from 60% to 40% seem to do the least damage to either type of battery. This is wholly practical if you are nearly homebound - roflmao!

4) Likewise, plugging in every night to recharge from a 50-60% charge to a target of 80-90% is to be preferred over allowing discharge to 20% over several days before a recharge back to 80-90% (due to crystalline cracking and electrolyte coating of the crystals).

5) Your stoic dedication to maximizing your battery's life to attain that 800,000 mile nirvana will likely result in a still healthy battery, as your 400-500K vehicle is hauled away to the scrap heap; due to failure of the frame, or any of various body or electronic components that end a vehicle's useful life (especially after an extended warranty times out and you are paying the full costs of repairs).

So, for our 2023 MME with its cold-weather-tolerant, extended range, NiCad battery; we will plug it in every night to recharge to 80%; but not hesitate to take it to 100% in anticipation of trips over 150 miles. The same approach would be true if it were the standard range Li-ion battery.

I see this approach akin to my changing the oil in my ICE diesel GMC Canyon only when its Info display says it is down to <10% life; and not the 3000 miles I see recommended by some owners, "if you really want that engine to last"!

Peace/Out

Great piece?

Mind blown ?

30,000 per year and working tends to dictate battery use.

I think my best bet is to just charge as I need and want and to what extent, drive in whatever conditions my work dictates and just not worry, enjoying the ride which I certainly do.

Even as I use Stangy, which probably goes against all the good advice apart from extremes of temperature, it seems likely the car will still become end-of-life before the “battery”, though unlikely to, entirely or partially fails or degrades to a point it’s unusable.

Insofar as any battery worries are concerned, to coin a phrase, does my face look bovvered???

 

[markboris]

I never use VIN decoders because I've seen too many inaccuracies with them. Ford lists descriptions for all 17 digits of the VIN for each model car in their repair manual. This is what Ford shows for the 8th digit of the VIN on the Mach-E:

The eighth VIN position identifies the electric motor, battery type, type of drive unit:

● 4 - Electric Motor, 72kWh usable LFP standard range battery, rear primary drive unit

● 5 - Electric Motor, 72kWh usable LFP standard range battery, rear primary drive unit, smaller
secondary drive unit

● 7 - Electric Motor, 88kWh usable extended range battery, primary drive unit

● E - Electric Motor, 88kWh usable extended range battery, limited rear primary drive unit, limited
larger secondary drive unit

● M - Electric Motor, 68kWh usable standard range battery, rear primary drive unit

● S - Electric Motor, 68kWh usable standard range battery, rear primary drive unit, smaller
secondary drive unit

● U - Electric Motor, 88kWh usable extended range battery, rear primary drive unit, smaller
secondary drive unit

● X - Electric Motor, Performance 88kWh usable extended range battery, rear primary drive unit,
larger secondary drive unit

 

[ChasingCoral]

...and folks wonder why ICE and hybrid ICE continue to dominate sales as BEV's have flatlined and all product plans been delayed or cut back...

Not sure what you are implying. It's no more confusing than different grades of gasoline or gas vs. diesel. See what happens if you put gas in your diesel car!

 

[Sparty]

The 8th digit of my VIN is 'U'.

So is mine and that equals the NiCad extended range/Colorado Springs cold Winter friendly...Congratulations on your choice!

 

[MightyMike]

Not sure what you are implying. It's no more confusing than different grades of gasoline or gas vs. diesel. See what happens if you put gas in your diesel car!

He is saying that the technology is too complicated for the average person to use or understand.

But I think this discussion is likely a fringe discussion anyway (as stated by someone earlier). We're talking about whether we are going to have a battery that lasts 800k or 700k. Well beyond the service life of the vehicle.

The bigger technological issue (for which this sentiment really does apply), is that the GOM drives range anxiety because of so many factors that go into maximizing battery range. The reason we fuss over this is because the manufacturer insist on giving us the maximum possible range. So you are exposed to ideas like charging to 100% and charging curves and all this other nonsense.

I would much rather have 200 miles of range guaranteed over 250 miles of range (maybe, if you have a tailwind, in 70 degree temperature).

I want to be able to charge up anyway I want (with the understanding that my battery will last marginally longer or shorter based on my behavior), and go to my destination with certainty that I will get there based on the GOM.

 

[Sparty]

I know, it's a bit off topic, but I attached two VIN decoding guides, one from 2022 and another one from 2024.
And if I am not mistaken, the LFP was introduced in the Mach-E in 2023. So all older models shall have NMC batteries only.

I believe you are correct......and guess what......contrary to the MAGA crowd the LFP costs Ford less to produce and requires fewer scarce resources.....so they began putting it in.....and charged $3000 for the NiCad.

 

[Sparty]

He is saying that the technology is too complicated for the average person to use or understand.

But I think this discussion is likely a fringe discussion anyway (as stated by someone earlier). We're talking about whether we are going to have a battery that lasts 800k or 700k. Well beyond the service life of the vehicle.

The bigger technological issue (for which this sentiment really does apply), is that the GOM drives range anxiety because of so many factors that go into maximizing battery range. The reason we fuss over this is because the manufacturer insist on giving us the maximum possible range. So you are exposed to ideas like charging to 100% and charging curves and all this other nonsense.

I would much rather have 200 miles of range guaranteed over 250 miles of range (maybe, if you have a tailwind, in 70 degree temperature).

I want to be able to charge up anyway I want (with the understanding that my battery will last marginally longer or shorter based on my behavior), and go to my destination with certainty that I will get there based on the GOM.

THIS GENTLEPERSON JUST HIT THE PROVERBIAL NAIL ON THE HEAD! I'M GOING ON 73 AND DON'T WISH TO EXPEND THE ENERGY TO HAVE MY FRIGGING BATTERY LIVE LONGER THAN I DO.

Just enjoy the immense fun of driving an MME in 1 pedal mode; and thank the programmer who came up with the Ford App feature that let's you set a one-time charge target to 100%, and then revert back to the battery friendly 80%.

 

[phidauex]

I see this approach akin to my changing the oil in my ICE diesel GMC Canyon only when its Info display says it is down to <10% life; and not the 3000 miles I see recommended by some owners, "if you really want that engine to last"!

You hit the nail on the head - these discussions about maximizing battery life are interesting, but are the analog of people arguing for hundreds of pages over the results of an oil analysis test and whether their oil should have been changed at 5400 miles or 6150 miles, or whatever. If you love the tech and find it fascinating, then go nuts, but no one should think they have to know this stuff to have an EV.

The biggest variable for degradation is just calendar life - everything else is just a tiny bit of optimization. I set my home charger to 80% max, but charge to 100% whenever I have a trip. On a trip I charge to whatever, whenever. LFP batteries do benefit from an occasional charge to 100%, but I don't think anyone needs to put it on their calendar - just do it before a trip and then it is done. I work in large scale energy storage and have deployed GWhs of batteries - even on the largest systems in the country we put a lot of energy into getting the BMS setup right to begin with, but then very simple operating parameters for the battery day to day.

Also, quick note to everyone who has started calling them "NiCad" batteries - they aren't, that is something totally different (your yellow rechargeable flashlight batteries from the 80's). In this case, NMC is Lithium-Ion Nickle-Manganese-Cobalt, as compared to LFP, which is Lithium-Ion Iron-Phosphate.

 

[Sparty]

You hit the nail on the head - these discussions about maximizing battery life are interesting, but are the analog of people arguing for hundreds of pages over the results of an oil analysis test and whether their oil should have been changed at 5400 miles or 6150 miles, or whatever. If you love the tech and find it fascinating, then go nuts, but no one should think they have to know this stuff to have an EV.

The biggest variable for degradation is just calendar life - everything else is just a tiny bit of optimization. I set my home charger to 80% max, but charge to 100% whenever I have a trip. On a trip I charge to whatever, whenever. LFP batteries do benefit from an occasional charge to 100%, but I don't think anyone needs to put it on their calendar - just do it before a trip and then it is done. I work in large scale energy storage and have deployed GWhs of batteries - even on the largest systems in the country we put a lot of energy into getting the BMS setup right to begin with, but then very simple operating parameters for the battery day to day.

Also, quick note to everyone who has started calling them "NiCad" batteries - they aren't, that is something totally different (your yellow rechargeable flashlight batteries from the 80's). In this case, NMC is Lithium-Ion Nickle-Manganese-Cobalt, as compared to LFP, which is Lithium-Ion Iron-Phosphate.

Thanks for the clarification.....i sit here corrected......LiFePO4 or LFP for short.

 

[cswebster]

This video should help settle some confusion.

Video Description:

Electric cars are becoming increasingly popular, but a common concern remains for many owners - what about the battery? Most batteries used in electric cars today come with one of two major chemistries: Nickel Manganese Cobalt (NMC) or Lithium Iron Phosphate (LFP). LFP batteries are rising in popularity as they're cheaper to manufacturer, and more sustainable since they use more common materials. Each chemistry has unique properties, and benefits from specific best practices, as it relates to making the battery last for a long time. This video will look at the latest research and discuss four major best practices for LFP batteries when it comes to capacity retention and longevity.

Jason is amazing. Wicked smart. Thanks for posting

 

[Ford_orr]

When home I set it to 85%. But for long trips I change it to 100% although I stop the public charger way before that when I can.

According to the NCM video from this guy ( How To Ruin Your Electric Car's Battery - NMC Edition! (youtube.com) ), even if you do everything wrong, the battery will probably still outlast the life of the vehicle. I think in the long run, charging to 75 or 90% is hair splitting. Personally, I do 85%. And after watching the video, not only do I feel validated to use this number, but also more at ease knowing that I "probably" won't have to replace the battery in 10 years if I still own the car.

 

[codatory]

An important note to remember is that these tests are conducted against the bare cells and don't include the OEM's various BMS implementations (such as buffers, etc). I think the real learning from these videos (as Jason suggests) is to take what you can, combine it with the OEM recommendations, and apply it to how you use the car.

For example, I have an LFP pack. I typically charge to 100% on Saturday night because my Sunday drive will push it back down to <90% and I chip away at the rest during the week. This way I get the BMS calibration from going to 100%, but I am not storing it there - especially during the summer heat. If I drop below 30% during the week, then I'll queue up another charge to 80/90%, that way the battery is always plenty ready for whatever comes up. The cycle life of LFP means the battery in my car is primarily going to degrade by calendar aging and not by cycle aging, so this method avoids the worst of the cycle aging behaviors while still being completely compatible with my lifestyle.

 

[jasdf2345]

...and folks wonder why ICE and hybrid ICE continue to dominate sales as BEV's have flatlined and all product plans been delayed or cut back...

EVs problem isn't battery "maintenance", it's people's fears they won't be able to charge, charge time, and biggest of all, the price of an EV over a comparable ICE vehicle.

We do not need to maintain these batteries. Just limit charging to 90% as Ford states and that's it. Anything else being done likely has limited to no value except perception.

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