(answered)Concern on charging to 100% every charge.

Mirak

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Agreed that charging a lithium battery to 100% regularly is bad for its health as it speeds up the process of dendrite formation. The manual recommends charging to 90% for longevity. But the key point is that there is already a big buffer built in software by Ford, so even 100% is not 100%. The max usable portion of an extended range battery is 88 kWh, but the actual pack capacity is 98.7 kWh, so when you charge it to 100% it's actually only charged to 89% and when you charge it to 90% you're actually charging it to 80%.
I'm not disputing your math, but are we confident that is what Ford is using the actual pack capacity when it recommends only charging to 90%? That seems unlikely to me. For the owner's purposes, the max capacity is 88kWh, so it would seem that Ford is recommending to only charge to 90% of that. Otherwise why would Ford even include the recommendation since you can't charge past 88kWh anyway?
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CHeil402

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I'm not disputing your math, but are we confident that is what Ford is using the actual pack capacity when it recommends only charging to 90%? That seems unlikely to me. For the owner's purposes, the max capacity is 88kWh, so it would seem that Ford is recommending to only charge to 90% of that. Otherwise why would Ford even include the recommendation since you can't charge past 88kWh anyway?
I agree. That's my point is that Ford recommends charging to 90% range-o-meter state of charge (which is really 80% battery SOC) to maximize life. But even in the event you regularly charge to 100% you're not actually charing to 100%, so it's not as damaging to the battery and is ok to do regularly as an end user hence the 8 year warranty which is not voided if you regularly charge to 100%.
 

Woeo

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Honestly I didn't even look if my Mach-E *has* a glovebox. Can't think of what I'd need or use it for. Just a fancy Cabin Air Filter service door, IMO.
Where do you keep your papers? I have a suggestion if your glove box isn’t your first thought.
 

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Where do you keep your papers? I have a suggestion if your glove box isn’t your first thought.
Proof of insurance is an app on phone, registration in the wallet with the license.
 

machefan

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I agree. That's my point is that Ford recommends charging to 90% range-o-meter state of charge (which is really 80% battery SOC) to maximize life. But even in the event you regularly charge to 100% you're not actually charing to 100%, so it's not as damaging to the battery and is ok to do regularly as an end user hence the 8 year warranty which is not voided if you regularly charge to 100%.
I personally suggest folks follow the manual and this keeps getting asked over and over which is fine. Charge to 90% and you are 80% which takes into account the built in buffer and Fords current recommendation. Battery degradation is a real thing, one can slow it down or speed it up. 100% charge is 90% this is true, because we can only use 88 (kW) of it. The bad part is that 90% leaves some cells full at a high SOC which is not good. If Ford unlike others have found a way to balance this out then 100% would be fine, however I am guessing 90% charge is there for this reason or they wouldn't have put it in the manual.

If I am wrong, I am wrong, charge to 100% and see what happens in a few years, might be very little as others have said might be more. The chance of a battery replacement is rare because 70% of total capacity is not likely more like 95% - 90%. Looking at other EV's with battery management this is about what they experience.

I don't agree going lower than 90% will yield any measurable difference over time.

There are a ton of articles on this but most of it circles around each MFG, no two are alike etc.
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