WetEV
Posts: 2253
Joined: Fri May 04, 2012 8:25 am
Delivery Date: 16 Feb 2014
Location: Near Seattle, WA

Re: This is normal?

Tue Jun 12, 2018 8:07 am

briscobully wrote:1. Can you not rely on the the remaining kWh displayed on LeafSpy?


Depends on exactly what you mean by "rely" or "trust". No measurement is completely accurate, there is always a margin of error. It is prudent to understand the error budget if you are going to be cutting it close.

The GOM is the worse, for sure. Not only the car's estimate of battery capacity, but also the slightly nutty way the car takes recent efficiency and turns this into a range estimate. I've seen single digit GOM readings at the top of a climb, then driven 35 miles and still had 20 miles left.

https://www.google.com/maps/dir/Dungene ... !3e0?hl=en


A full L2 charge from LBW with the battery at 20C and measuring the total kWhs used is probably the closest to a gold standard battery capacity test that we could do without expensive equipment.

% charge remaining is reasonably accurate, unless you are doing a lot of high power acceleration/regeneration.

The car's km/kWh or miles per kWh is somewhat less accurate, but better than the GOM.

A test such SageBrush suggested is probably more accurate than LeafSpy. I've seen LeafSpy's kWh more than 10% high, and 2% low, based on a capacity determined by a recharge test. Still rather better than the GOM.
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

briscobully
Posts: 46
Joined: Wed Mar 14, 2018 8:04 am
Delivery Date: 02 Jun 2018
Leaf Number: 315457
Location: Chicago, IL

Re: This is normal?

Tue Jun 12, 2018 9:03 am

WetEV wrote:
briscobully wrote:1. Can you not rely on the the remaining kWh displayed on LeafSpy?


Depends on exactly what you mean by "rely" or "trust". No measurement is completely accurate, there is always a margin of error. It is prudent to understand the error budget if you are going to be cutting it close.

The GOM is the worse, for sure. Not only the car's estimate of battery capacity, but also the slightly nutty way the car takes recent efficiency and turns this into a range estimate. I've seen single digit GOM readings at the top of a climb, then driven 35 miles and still had 20 miles left.

https://www.google.com/maps/dir/Dungene ... !3e0?hl=en


A full L2 charge from LBW with the battery at 20C and measuring the total kWhs used is probably the closest to a gold standard battery capacity test that we could do without expensive equipment.

% charge remaining is reasonably accurate, unless you are doing a lot of high power acceleration/regeneration.

The car's km/kWh or miles per kWh is somewhat less accurate, but better than the GOM.

A test such SageBrush suggested is probably more accurate than LeafSpy. I've seen LeafSpy's kWh more than 10% high, and 2% low, based on a capacity determined by a recharge test. Still rather better than the GOM.



Thanks WetEV,
My question, I guess, is should I use the LeafSpy readings as my beginning and ending SOC or the instrument panel? Or, as long as I'm consistent, using only one or the other should give me the same baseline of information? I think I'm asking that correctly... As of right now, my battery number remaining, as show on the Leaf instrument panel, and the SOC that LeafSpy shows are different my about 6%... Is that normal?

And, if I do use leafspy to determine my kWh's used, I would assume I'd need no 'fudge' percentage as SageBrush suggests if I get the reading from ChargePoint.

Thanks all
2015 Leaf 'S' w/ QC package - Brilliant Silver - 12 Bar / ODO- 13,845 miles/ Ahr =60.81 / SOH= 91.52 / QC = 10 / L1/L2 = 420

briscobully
Posts: 46
Joined: Wed Mar 14, 2018 8:04 am
Delivery Date: 02 Jun 2018
Leaf Number: 315457
Location: Chicago, IL

Re: This is normal?

Tue Jun 12, 2018 10:01 am

My stats from my latest charge (using LeafSpy Pro stats)

Before charging:
6.6kWh (remaining on battery)
SOC = 39.4%

After Charging:
17kWh
SOC = 82.4%

By these numbers I get this as my battery kWh;
6.6 - 17.0 = 10.4kWh
Change in SOC - 82.4% - 39.4% = 43%

10.4/.43 = 24.186kWh = is that even possible on a 24kWh 2015 Leaf S? Or are my calculations incorrect? Or is LeafSpy not reading correctly? Hence my first question on Page 5 above

And BTW, I only charged it because I wanted to see if the Charging station down the street was active or not...
2015 Leaf 'S' w/ QC package - Brilliant Silver - 12 Bar / ODO- 13,845 miles/ Ahr =60.81 / SOH= 91.52 / QC = 10 / L1/L2 = 420

alozzy
Posts: 1071
Joined: Fri Jan 20, 2017 4:25 pm
Delivery Date: 18 Jan 2017
Location: Vancouver, BC
Contact: Website

Re: This is normal?

Tue Jun 12, 2018 10:39 am

17 kWh @ 82.4% SOC would extrapolate to (17 kWh * 100%) / 82.4% = 20.6 kWh @ 100% SOC, but your method should have worked too. Seems that the SOC reported to LeafSpy is a little flawed.
Vancouver, CA owner of a 2013 Ocean Blue SV + QC, purchased 01/2017 in WA
Zencar 12/20/24/30A L1/L2 portable EVSE
1-1/4" Curt #11396 hitch
After market, DIY LED DRLs
LeafSpy Pro + Konnwei KW902 ELM327 BT OBDII dongle
Loving my first BEV :D

User avatar
jlv
Posts: 840
Joined: Thu Apr 24, 2014 6:08 pm
Delivery Date: 30 Apr 2014
Leaf Number: 424487
Location: Massachusetts

Re: This is normal?

Tue Jun 12, 2018 10:42 am

briscobully wrote:10.4/.43 = 24.186kWh = is that even possible on a 24kWh 2015 Leaf S? Or are my calculations incorrect? Or is LeafSpy not reading correctly?
That assumes that a 100% SOC is a full charge. For instance, when my 2013 finishes charging, LSP reads the SOC as 96.7%.

IMHO, the easiest way to know the current battery capacity is to just fully charge the car and use LSP to read it.
'13 SL+Prem (mfg 12/13, leased 4/14, bought 5/17) 32K miTesla S 75D (3/17) 25K mi
Model 3 reservation (still undecided)

briscobully
Posts: 46
Joined: Wed Mar 14, 2018 8:04 am
Delivery Date: 02 Jun 2018
Leaf Number: 315457
Location: Chicago, IL

Re: This is normal?

Tue Jun 12, 2018 12:25 pm

jlv wrote:
briscobully wrote:10.4/.43 = 24.186kWh = is that even possible on a 24kWh 2015 Leaf S? Or are my calculations incorrect? Or is LeafSpy not reading correctly?
That assumes that a 100% SOC is a full charge. For instance, when my 2013 finishes charging, LSP reads the SOC as 96.7%.

IMHO, the easiest way to know the current battery capacity is to just fully charge the car and use LSP to read it.


Unless, the LeafSpy figured is flawed as alozzy pointed out.

Right now my Leaf console reads a 27% SOC but LeafSpy reads 34.9%? The Gids% reads 25.3%. Oh, did just drive and knocked another kWh off the calculation I posted above (if anyone is keeping track of my numbers besides me)!

Again, which stat do you trust?
2015 Leaf 'S' w/ QC package - Brilliant Silver - 12 Bar / ODO- 13,845 miles/ Ahr =60.81 / SOH= 91.52 / QC = 10 / L1/L2 = 420

finman100
Posts: 328
Joined: Thu Sep 20, 2012 10:42 am
Delivery Date: 06 Jun 2014
Location: Albany, OR

Re: This is normal?

Tue Jun 12, 2018 2:29 pm

I trust and use Leaf Spy kWh exclusively. So far so good.

The GOM is a nice reference to compare, but I've figured out most of my routes and most of the kWh needed and utilizing LeafSpy has not left me stranded due to inaccurate numbers.

In fact, LeafSpy has "extended" my range (which is down to 70 miles from 80ish when new) just due to the fact I know when I'm in that 1 to 2 kWh range, I better slow down or ensure the next charging spot is 6 miles away or less. I use LeafSpy numbers to turn off the heater when needing a bit more of a buffer to avoid being stranded.

All in all, the kWh is what I have adjusted to to tell me how much is left "in the tank". And my miles per kWh is a pretty consistent 4. sometimes less in the rain and cold, more in the glorious summer that is here early this year. I do some math in my head and have been successful for 46,000 gas-free miles.

YMMV

PS My advantage is our relatively moderate temps here in the Willamette valley as well as the obvious flatness that comes along with a valley, haha. Not to say there aren't hills and passes, but 900 feet climb over the Coastal Range is VERY different than my one-time trip over the 10,000' Cascades!
Albany, Oregon
2014 Silver SV with charge/LED package. June 2014, I'm in the EV game!
46,000 miles
17.5 kWh on 100% charge (51-ish Ah), down 1 bar
4.2 miles/kWh average
Best trip: all of 'em. They're all no-gas!

GerryAZ
Gold Member
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Delivery Date: 12 Jun 2011
Location: Phoenix, AZ

Re: This is normal?

Wed Jun 13, 2018 1:26 am

Dash SOC ranges from 0% to 100% while actual SOC is probably 3% to 97% +/- a bit. Leaf Spy is using numbers that are more like the 3% to 97% range. I have been tracking battery capacity by discharging until main contactor opens (shutdown) using climate control in the driveway and then charging fully. I measure the charging energy using a revenue-accuracy watt-hour meter on the input side of my EVSE. I started my monthly discharge/recharge tests when the battery was replaced in the 2011. My experience has been that dashboard mi/kWh was around 25% optimistic on the 2011 and closer but still optimistic on the 2015 when compared to true wall-to-wheels efficiency calculations. Actual efficiency of the 2011 was about 3.0 mi/kWh while the dash consistently indicated at least 4.0 mi/kWh for my usage pattern. The "GID", AHr, and SOH numbers from Leaf Spy seem to track fairly well with the measured recharge energy on both 2011 and 2015 so Leaf Spy data is the best information available without using external measurements.
Gerry
Silver LEAF 2011 SL rear ended (totaled) by in-attentive driver 1/4/2015 at 50,422 miles
Silver LEAF 2015 SL purchased 2/7/2015

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