Page 3 of 10

Re: What SOC% does each bar on Leaf dash represent ?

Posted: Thu Feb 24, 2011 10:54 am
by garygid
Just because the car has a high-precision (like 45.23567%, or even 45.2%) SOC value, that does not mean it is very accurate (could be 45.2% +/- 10%).

I suspect that the SOC data value is just an estimate, although an "educated" estimate.

The relative values might be reasonably good, but the absolute values MIGHT be substantially wrong.

Re: What SOC% does each bar on Leaf dash represent ?

Posted: Thu Feb 24, 2011 11:00 am
by evnow
turbo2ltr wrote:Here's what was logged while charging.
Thanks, I'll update.

Re: What SOC% does each bar on Leaf dash represent ?

Posted: Fri Feb 25, 2011 2:02 pm
by kolmstead
That's some great looking data, Turbo! You're right; bar 5 on discharge should be right around 36.3% SOC. I was intrigued that the slopes are slightly different; 8.0 % per bar on discharge, 8.2 on charge. But discharge is really all we care about, anyway. You're doing some fascinating things with CAN bus! I'm still pondering the heavily damped OAT display. Pretty goofy.

-Karl

Re: What SOC% does each bar on Leaf dash represent ?

Posted: Thu Mar 03, 2011 5:30 pm
by klapauzius
Just note that the available charge is not 24 kWh but apparently 20 kWh. The top and bottom 2kWh are, according to Nissan, used to buffer the battery vs. overcharging and full depletion.

Re: What SOC% does each bar on Leaf dash represent ?

Posted: Thu Mar 03, 2011 5:43 pm
by DaveEV
klapauzius wrote:Just note that the available charge is not 24 kWh but apparently 20 kWh. The top and bottom 2kWh are, according to Nissan, used to buffer the battery vs. overcharging and full depletion.
It's been shown that the actual battery capacity is around 27-28 kWh, not 24. 24 kWh is total usable.

Re: What SOC% does each bar on Leaf dash represent ?

Posted: Thu Mar 03, 2011 7:58 pm
by klapauzius
I talked to some guy at Nissan and he gave me the 20 kWH usable capacity number. This matches with my experience. Where does the information about the 27-28 kWH come from? Could it be that the cap. is that much higher at warmer temperatures?

Re: What SOC% does each bar on Leaf dash represent ?

Posted: Thu Mar 03, 2011 8:06 pm
by evnow
klapauzius wrote:I talked to some guy at Nissan and he gave me the 20 kWH usable capacity number. This matches with my experience. Where does the information about the 27-28 kWH come from? Could it be that the cap. is that much higher at warmer temperatures?
We have been talking about that in this forum forever. There have been Nissan insiders telling forum members that the total capacity is more than 24kwh & the usable is 24kwh. As linked above there are some measurements ...

Re: What SOC% does each bar on Leaf dash represent ?

Posted: Sat May 07, 2011 9:34 pm
by MrFish
I think this is consistent with others have noted after the software upgrade.

So I had a lot of running around today with a mixture of Freeway and surface streets and the next thing I knew I was at the dreaded RED BARS! I was getting freaked out but my wife calmly said "you need to see how far you can go anyhow, so this is as good a time as any." So this is what I noted. (BTW, I did have the software update a couple of weeks ago.)
First, the SOC bars are definitely not linear. The first bar (#12) goes very quickly, sometimes as few as 5 miles, the next bars 11-4 seem to get about 7 miles each, #3 got 9 miles. When I got to the 2 red bars, the range guess-o-meter said 23 miles left and I'm thinking no way, however, bar #2 lasted 12 miles, then at 21 miles the range meter still showed 8 miles left. At 23.4 miles with 2 miles left on the range I received the low battery warning message and the SOC bars went blank. I continued to drive around at ~40 mph. At 29.7 miles I received the "turtle" and "reduced power". At 30.2 I was dead stopped in front of my house and needed to push the car up my driveway.

Summary:
2 red bars with 23 miles left on range meter.
0 red bars at 21 miles traveled (last 2 bars 10.5 miles average each)
8 miles traveled with 0 bars left before "turtle"
0.5 miles on turtle before stopped dead.
Total 30.2 miles traveled on 2 red bars at 4.0 kw/mile.

There seems to be a significant (~10%) cushion in range from the last 2 SOC bars to battery cut off.

Re: What SOC% does each bar on Leaf dash represent ?

Posted: Sat May 07, 2011 9:44 pm
by evnow
MrFish wrote:Summary:
2 red bars with 23 miles left on range meter.
0 red bars at 21 miles traveled (last 2 bars 10.5 miles average each)
8 miles traveled with 0 bars left before "turtle"
0.5 miles on turtle before stopped dead.
Total 30.2 miles traveled on 2 red bars at 4.0 kw/mile.

There seems to be a significant (~10%) cushion in range from the last 2 SOC bars to battery cut off.
Definitely they have remapped the bars. You got 10 miles on the 2 red bars (instead of 7 in others) and ten more after that. Is this all ath about the same speed ?

The first bar going off a little early (5 instead of 7) could be because of some remapping (i.e. they actually move to lower bar at a higher SOC%) or lack of cell balancing and thus not charged to "real" 100%.

Re: What SOC% does each bar on Leaf dash represent ?

Posted: Sun May 08, 2011 7:03 pm
by MrFish
As a follow-up, I recharged with L1 and a Killawatt meter. It required 27.65 kw AC to charge to 100% from dead, so it is safe to say that there was at least 24kw available from the battery pack, even with a 88% charging efficiency.