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It's hard to know who to trust anymore.
The percentage? The fact it still needs a half hour to charge? Definitely not the guess-o-meter...
Watch Speedometer Gauge Automotive design Motor vehicle


I've read about the process of running the battery fully dead then doing a complete charge to realign some of these numbers. Is that recommended here?

(I do my best to read and research before I ask questions, but I will admit my understanding of cars, much less electric, is rudimentary. Sorry if this is obvious or repetitive!)
 

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This is likely not a calibration issue. It is the car guessing how long it will take to balance the battery pack. Balancing happens when the car is fully charged. If the cells are way out of balance, it will take longer to complete the charge. If they are pretty close it won't take long to finish.
 

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2013 FIAT 500e
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Combustion car knowledge that's useful in an EV, in addition to tires/wheels, includes:
  • 12V starter battery & electrical system (bulbs, fuses, wipers, windows, locks, etc.)
  • Cooling systems (only big difference is the pump is electric)
  • A/C (only big difference is an electric compressor instead of belt-drive)
  • Suspension/steering/brakes (only big difference is the brake booster is an electric fluid pump)
  • Drivetrain (CV joints, wheel bearings)

It's hard to know who to trust anymore. The percentage? The fact it still needs a half hour to charge? Definitely not the guess-o-meter...

I've read about the process of running the battery fully dead then doing a complete charge to realign some of these numbers. Is that recommended here?

.... Sorry if this is obvious or repetitive!)
No need to be sorry, since it's definitely not obvious, & it took all of us a while to either figure it out or search for others' experiences:

"The fact" is it never needs as long to charge as it shows.

Percentage is by far the most trustworthy reading* to estimate range OR charge time. Charging generally adds about 25% per hour on L2 (240V at 30 amps or more) with each % taking a little over 2 minutes.

With the OEM cord on 120V it's about 5%/hour or 1% every 10 minutes. It's barely more than With the OEM cord on 240V it's about 10%/hour or 1% every 5 minutes.

The only really big exception is the final percent from 99% to 100%, since as Kiesling noted, that one takes at least a bit longer, because it's balancing every cell all the way up to their peak levels. However, there's no need to wait for it to do that more than once in a while, unless you need absolute peak range.

The GOM is actually pretty accurate IF you drive at a fairly consistent speed & temperature. For example my normal route in very mild coastal southern Ca. switches every few miles from city to highway speed & back to city speed again, so the average speed is about the same for any given 10 miles, which is the distance the GOM is based on. My GOM usually shows almost exactly 1 mile per %, which almost exactly matches the car's range.



* The % does seem to eventually begin to read extra-low at the LOW end, but running it dead only recalibrates that one number, so the only reason to bother is if you're going to need to drive until it says 0% & therefore will want to know how much more is really left (& even then, you can just use OBD for the true %). If you're only going to drive until the gauge says 10%, it likely won't matter if there's actually 20% still left.
 

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I don't see nearly 1mi/%. However I live in a hilly area, hills are tough on battery levels. Plus it is usually cool enough to need HVAC this time of year. I am eager to see the difference come spring & summer.

One thing of note that I noticed when I did a discharge till not move calibration. There was a spread in highest/lowest SOC of the cells and the GOM was seeming to track with the lowest cell.

Sent from my Pixel 3a using Tapatalk
 

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Ya, I should have wrote "YMMV":
  • Recalibration won't help at all, if it's not OUT of calibration (check on OBD 1st, at a low %).
  • I get 1mi/% because my drive is mostly city speeds (75% city, I think) without heat, but it is with daytime headlights, which take more than twice the power of a seat heater!

Speed decimates range. CABIN heat kills it too, especially if you can't preheat while charging, but 1 seat heater is even less than half as much as just headlights. Hills REALLY kill it if you can't regen above 6mph all the way back down.

Specifying "HVAC" can sometimes need clarification because unlike heat, moderate A/C* doesn't affect my range at all in mild coastal heat like 90F. Apparently that's because the battery is so much more efficient when warm.

* High 70s with med-low fan, & passenger vents off.
 
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