That last bar - is my iMiEV doing more behind the scenes?

[WyVern]

Apologies if this is discussed elsewhere, I searched but couldn't find an appropriate topic for my query - let me know and I'll shift the discussion if necessary.

My query to those in the know is why would my iMiev only show an 89km range after 4hrs charging from a displayed half capacity (charging on a 15A circuit) when all bars of the battery meter except the last were filled by the end of that 4hr charge?

My two theories are either:
A - that the battery actually had less than half a charge regardless of the display;
or
B - that the iMiEV does something specific during that last bar of charge to balance the charge across the pack and reflect the 146km range I had from a full overnight charge the night before and by ending the charge a bar short I missed out on this step.

Having only taken ownership 2 days ago and having drained the pack entirely on that first 150km highway run, to then perform a full overnight charge I just have a niggling concern I may have overstressed something. Tonights overnight charge will tell but I figured I'd throw it out there to those in the know to set my mind at rest.

Thanks, Dom.

 

[Don]

There are lots of discussions on both the 16 segment 'fuel' gauge and the computer generated RR number, but you'd probably have to have read the entire forum to glean the answer to your question, so no fault at all for asking again

Yes, the battery does go through a cell balancing procedure during the last 30 to 45 minutes of the charge cycle, but I don't believe this is going to change your RR number from 89 at 15 bars to 146 at 16 bars . . . . at least it shouldn't. I'll bet when your charge is all finished, your new RR number will be something between 100 and 110 and not 146 as it was last time you recharged

Basically, the two indicators have next to nothing in common and that's what's driving you nuts - You're looking for a correlation between them that just isn't there

If you have 8 bars showing on the fuel gauge, you should indeed have a battery that's about 50% charged. How far that 50% remaining can take you, or how far the 50% you're replacing can take you is an entirely different matter. When you've had the car longer, you'll come to realize that a full charge could mean you can go 150 to 160Kms . . . . or maybe only 75 or 80 Kms, depending on how and where you drive and how much climate control you use

The computer generated RR meter attempts to give you a good range projection number, but the displayed number is almost completely dependent on what you did over the previous 25 Kms, so if what you were doing then accurately reflects how you will drive the next 100 to 150 Kms, then it's a pretty accurate number. But, if you ran the previous 25 Kms uphill at full throttle (or downhill with very little throttle) before you recharged, then the new number will be badly skewed and nearly meaningless for what's likely to happen in the future

If you recharge at home and you live at the top of a hill that you must climb everyday to get back home, your RR numbers will always be unusually low and you will probably notice that when you leave home and go down the hill that you can go a long way without the RR number going down very much . . . . it might in fact even go UP as you drive. The opposite is also true - If you live at the bottom of a valley and the last 25 Kms of your trip home is always downhill using very little throttle, your number isn't going to be representative of what you can expect either

So, long story short, don't spend too much time trying to link the two displays together, especially not until you get a good feel for what the RR number is trying to tell you. It's a useful projection of what might be happening in the future, distance wise, but it's not an absolute number by any means and it can be really inaccurate, depending on what was happening over the previous 25 Kms

Don

 

[WyVern]

Phew! Thanks for that. We bought the MiEV for me as a second car to commute in but after driving it my wife has insisted she have it as she does the most miles and its "cute" apparently.

As this gauge confusion occurred as she used the car for the first time I needed a fast and certain answer. I sure got it.

Thanks for taking the time to clarify, in the meantime it looks like I shall only see "my" MiEV at he weekend!

 

[Don]

You'll find the terms 'leadfoot' and 'featherfoot' discussed here from time to time - Based on your descriptions, it sounds like you have one of each in your family . . . . I'll leave it up to the two of you to discuss who is which one :lol:

Hint: When the featherfoot drives the car and recharges it, the RR number is high . . . . probably 140's or more - The leadfoot, not so much

Don

 

[MLucas]

After awhile you won't even be looking at the RR gauge. I rarely ever use it unless I'm getting really low on charge and have to see what my possibilities are*. I generally know how far I can go now based on how I choose to drive the car. My daily commute is the same everyday, nothing different, I know exactly where each and every bar disappears at. I know that I'm going to arrive in Buffalo, Ny with 5-6 bars down in the summer and 7-8 down in the winter. It never changes. I use the outside temperature more as that gives me a better indication of how far I can go. Around town driving, I just don't care at all. I'm close enough to home to get a charge but I find my around town driving even with the air running, my whole family aboard and with spirited driving I can go all day with one charge.




*I rarely see low charge anymore as I've learned about the car and how far I can go.

 

[Don]

After awhile you won't even be looking at the RR gauge

I suppose it's a matter of personal preference

We're retired, so no 'daily commute' and all of our trips are much different - Some long, some short, most using the A/C and we only recharge every second or third day. The RR display is all we ever look at . . . . Oh, when it gets down to about 40 miles or so, I may glance at the fuel gauge to see that it's showing about half a tank, but that's about the only time we ever look at the bars display - We never have anything but RR displayed on the multifunction gauge (I wish I could just delete 3/4ths of it's other functions) and if it wasn't there, we'd sure miss it

I'll agree that the RR display isn't for everyone and it depends a lot on both how and where you drive whether it's display is even meaningful, but for me, it's by far the best display in the car

Don