Conflicting information on how my battery is doing.

[gbshaun]

I just passed 10,000 miles and am trying to figure out how my battery is doing.
However I’m getting conflicting information and would welcome any thoughts on it.

Today I did a 64 mile r/t, with a little A/C, & by the time I got home I was at 4.3 M/kWh on the dash (yes I had zero’d it before I left)
2 bars showing
No low-battery warning
It steadily dropped down to 11 miles on the range counter ( I think that’s consistent with the bars)
This suggests I could have done around 75 miles.
75/4.3 gives my useable capacity at just 17.4kW@h

However, of that 64 miles, 53 miles were on the freeway at 65mph.
65mph is supposed to result in just 3.6 M/kWh
I'm going to say the 10 miles I did NOT at 65mph would have been 3 less if i had stayed at 65.
So, i could have done 64+11-3 = 72 miles at 65mph, that’s 20.0 kWh usable capacity

Trip details.
0.5 mi from my home to the I-5 freeway.
26.5 miles from Encinitas to the Coronado bridge. Cruise control set at 65mph the entire way (traffic is light at 11:30AM). The A/C was running lightly the entire time.
At the start of the bridge (27 miles) I was at 4.1 M/kWh

No net elevation change. Tailwind? Unlikely, and would show up on the way home.

10 miles was driven up and over the bridge twice @55mph, and around Coronado, slowly.
Then the same return journey of :
26.5mi @65mph
0.5mi surface street
By the time I got home I was at 4.3 m/kwh,

For me the bottom line is I can drive 64 miles, 54 of them at 65mph, and still have at least 11 miles left even if I did continue at that speed (or probably an additional 20 on surface streets)

Appreciate anyone's thoughts on this

Shaun

 

[smkettner]

Seems pretty good to me. You still have 12 capacity bars showing?

 

[gbshaun]

Seems pretty good to me. You still have 12 capacity bars showing?

Yes, on the once-a-week on average I charge to 100%. I'll often take that opportunity to do it without the LEAF timers so it can top- up by resuming charging again after first cutting off.

On 80% it has on several occasions only given me 9 bars.

I think my economy gauge has been reading differently ever since I had the firmware updated in Summer.

Does the economy figure include power used by the heater/AC?

Shaun

 

[DaveEV]

Tony's estimate of mi/kWh on the range charge is pessimistic - it's to be used as a general guideline for planning trips.

The efficiency meter includes HVAC usage.

With a new, 21 kWh usable battery and 4.3 mi/kWh you should have a range of ~90 mi from 100% to turtle.

You got home with 2 bars showing, which is good for at least 17 miles at 4.3 mi/kWh or 81 miles (and possibly a few more). Unfortunately, tough to tell exactly unless you actually drain it - sometimes there appears to be quite a bit extra energy hiding below LBW.

81/90 = 90% original capacity, or pretty much expected according to Nissan after 1 year of ownership. I ran the numbers through Stoaty's Battery Degradation Model spreadsheet and it predicts 9% capacity loss for a LEAF in San Diego driven 7500 mi/year and 16 months old.

 

[gbshaun]

Thanks for the input.
Overall I'm very pleased with the range that I get. If I can do 70 miles, with A/C, and barely compromising my speed, that's all good.

 

[KJD]

Shaun,
You might want to get a GID meter and use that to monitor you battery. The GID number is not perfect but it is a good indicator of how things are going battery wise.

I also find that it is much easier for me to estimate range based on the SOC number of 0 to 100%. The guess o meter on the dash just is not granular enough to see what is really happening.

http://www.wwwsite.com/puzzles/socmeter/" onclick="window.open(this.href);return false;