Battery only charging to 88%???

[GreaseMonkey]

Same here. Four month old car charges to 89% when set to 90%. Whatever. Not fussed about it.

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[stinsvic]

Could be a bad module, I’ve seen almost this exact thing on the Lightning forums where they wouldn’t charge past 88.

Check your target charge level check out screen shot!!

 

[OH2AZ2OH]

Mine just started doing this as well. It will charge to 100% fine, but 85% overnight charge consistently shows 82% on starting. My most recent update was the 12v battery management update, don’t think this happened before that.

 

[devmach-e]

If you’re worried about the battery, do a 100% charge and verify it gets there.

Losing 1-2% after the charge finishes and you start driving is somewhat normal due to Ford’s charge termination strategy (could be improved).

My Chevy Bolt EV would frequently say 88 or 87 percent when the target charge was set to 90%. I don't think Ford is alone in this. What "amuses" me more with Ford is when I do a charge to 100%, the reported kWh to empty is, say, 84, and it stays at 100% SOC even when the kWH to empty has dropped to 80 kWh. Only when it dips below 80 kWh does the SOC percentage start to drop.

 

[Ravensfan1996]

It happens, mine is set to 90%, sometimes I’ll get in and it will be at 89%, sometimes 91%. I think with the temps this Time of year going up and down rapidly it’s normal. Most of the time i see 90% though. Also your percent will drop quicker at the start of your trip as the car warms/cools the battery and interior etc.

 

[flapjake314]

Mine charged to 88% today, set for 90%. I assumed it was the funky spring weather, or maybe some partially ready server change that got pushed?

I plan to just see what it does next time I charge.

mine has started doing that for the past few months. it's almost always exactly 2% below the target. it says it reached target but as soon as i turn on car it's 88%. i'm guessing it's some kind of software bug...

 

[Tomm]

Mine did this as well for a while a few months ago. I ignored it and as weather had warmed up it seems it has fixed itself.

 

[spicy_taco]

For those who are seeing this discrepancy, are you on 120v or 240v? I thought it was because I started charging on 120v. I used to have a 240v charger but in the house I'm renting now I don't have a 240v plug. I never noticed it when charging on a 240v charger, but that was a few months ago.

 

[Mach-Lee]

I did do that once recently and it reached to 100% just fine, and it also held it there to discharge at a usual level that I was used to seeing. But that’s why it’s odd that it seems to only have an issue when charging to the recommended 90% daily charge. Since it’s also inconsistent though, I may need to try the 100% more frequently for a while to see if that is at least consistent when using 100% or not, although I would worry slightly about charging to 100% so much more frequently than I ever do currently.

I have a feeling this isn’t so much a battery issue as a software issue, but not enough data yet to be sure of that.

FYI charging to 100% is different than charging to 95% or less in terms of the charge termination. The 100% setting is the only time the battery will charge at constant voltage (absorption mode) until the battery won't take any more juice (which is why going from 99% to 100% can take an hour). 95% or less will charge constant current and stop as soon as a certain voltage target is reached, then the voltage relaxes during the off period and you end up with a couple percent lower SoC when you start driving.

What this means is the battery voltage and SoC won't decay nearly as much during the off cycle when charged to 100% compared to the other SoC targets. 100% is really a "pack in every electron possible" setting that is optimized for taking long trips (and is more stressful on the battery).

 

[Tomm]

I am Charging on 240 volt 60 amp dedicated circuit. But again, I ignore the whole thing.
Mach Lee, as usual, thanks so much for your expertise.

 

[OH2AZ2OH]

For those who are seeing this discrepancy, are you on 120v or 240v? I thought it was because I started charging on 120v. I used to have a 240v charger but in the house I'm renting now I don't have a 240v plug. I never noticed it when charging on a 240v charger, but that was a few months ago.

I am charging on 240V. Up until recently, when I charged to 85%, my battery would always read 85 or 86% on startup. I wouldn't have remarked on a 1 or 2% difference, but I am seeing up to a 4% difference from how it has behaved for the previous 3+ years.

I charge in a well-insulated garage that rarely drops below 50F this time of year, so this is not related to outside temperature swings. Past behavior would adjust estimated range based on exterior temperature, not charge level.

I am watching it, but I am not particularly concerned about it for now. I plan to do Mach-Lee's suggested battery recalibration procedure at some point, but finding a window when I can actually do it isn't easy. I am hoping that will take care of it.

 

[Mach1E]

I am charging on 240V. Up until recently, when I charged to 85%, my battery would always read 85 or 86% on startup. I wouldn't have remarked on a 1 or 2% difference, but I am seeing up to a 4% difference from how it has behaved for the previous 3+ years.

I charge in a well-insulated garage that rarely drops below 50F this time of year, so this is not related to outside temperature swings. Past behavior would adjust estimated range based on exterior temperature, not charge level.

I am watching it, but I am not particularly concerned about it for now. I plan to do Mach-Lee's suggested battery recalibration procedure at some point, but finding a window when I can actually do it isn't easy. I am hoping that will take care of it.

50 degrees is cold for a battery.

But if you want the charge to be higher in the winter, why not change your target charge to 87% or 90%?

All those numbers (except 100%) are just estimates anyways. State of charge is not an exact science.

 

[Snakebitten]

Target charge of 90% is not 90.2, or 90.8,.......

It's 90.0, so even the tiniest of tiny draw on the battery is going to yield 89% on the IPC.

If you load a SOC PID and give it a decimal point, it will all make sense.
Interestingly, charging to 100% does appear to be enough beyond 99% that the IPC can indicate 100% for a few miles.

 

[HuntingPudel]

My target SoC is 85%. My car almost always reads 85% when I get into it while it’s on L2 because the car stops charging some time over night, the voltage relaxes somewhat, then the battery preconditioning kicks in, restarting the charge. By the time I get in the car, the SoC has risen again to my target. ??

 

[OH2AZ2OH]

If my target charge is 85%, and the car charges to 85% and stops, but then later the car thinks the charge level has dropped to 84 or 83 or 82%, why is it not topping up since it is still plugged in?

50 degrees is cold for a battery.

But if you want the charge to be higher in the winter, why not change your target charge to 87% or 90%?

All those numbers (except 100%) are just estimates anyways. State of charge is not an exact science.

I do, and I understand that measuring exact charge level is tricky. That's not the point of this thread. Something has changed that now results in a 3-4% drop in indicated charge level after a charge. My garage was 44 degrees all winter, and charging to 85% left me with 85% or 86% on start up. Now my garage is 54 degrees, and a charge to 85% is now 82% on start up. I have had my car since Jul 2021, and up until the last month, it has behaved exactly the same on every not-100% charge, no matter what the temperature. Temp affected the estimated range, and maybe would cause a 1% drop when I left it outside for 8+hours, but never caused a drop in charge while it was still plugged in.

Either something has changed in the software (which I've already admitted is the most likely cause), or several of our batteries have all had a drastic change in the last month. Those of us experiencing this just want some confirmation that this is a software thing and not an indication that something bad has happened to our batteries.

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