Report Your Gid Number at 100% Charge

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80 watt-hours per GID, according to Nissan (source?).

Did Nissan say where these watt-hours are measured?

The wall, the charger input, the charger output,
going into the Pack, inside the Pack ... ?

These figures will all be (slightly to noticably) different.

It appears that a GID is NOT 80 watt-hours of usable energy
being recovered from the Pack to be used by the car, right?
 
80 watt-hours measured at the hall-effect coulomb counter. Obviously there is some amount of efficiency lost from charge to discharge due to the coulombic loss. The LBC (Battery ECU) will periodically correct the numbers to keep them accurate. You'll see this on occasion as a rapidly moving SoC/Gids with no significant load. I tend to observe this right after starting from a charge, but it levels off quickly. It also will sometimes correct with a "jump" during start-up when needed.

-Phil
 
garygid said:
80 watt-hours per GID, according to Nissan (source?).

Did Nissan say where these watt-hours are measured?

The wall, the charger input, the charger output,
going into the Pack, inside the Pack ... ?

These figures will all be (slightly to noticably) different.

It appears that a GID is NOT 80 watt-hours of usable energy
being recovered from the Pack to be used by the car, right?
Yes. I get 80 Wh into the battery only during charging. When driving/discharging, it appears to be around 75 Wh.
 
Ingineer said:
TonyWilliams said:
DaveinOlyWA said:
i was averaging .23 to .28 miles per GID....

i tried to monitor GID in town but the range on that was between .22 and .35 which was too much.

So, 281 Gids / 80 miles equals 3.5 Gids per mile.

Or 280 watt-hours per mile. (1 Gid = 80 watt-hours.)

-Phil

Phil, I get that you are providing the data that Nissan has provided, and Im confident that it is very useful for many things. For making calculations based on the available instruments to the causal LEAF operator (without LEAFSCAN, Consult XXXX, etc), it doesn't add up.

So, while I'm not disputing your source, 80 watt-hours has little meaning to that casual driver. I find it closer to 73-75 watts-hours of USEFUL, observed by the instruments in the vehicle, energy per Gid.
 
TonyWilliams said:
Phil, I get that you are providing the data that Nissan has provided, and Im confident that it is very useful for many things. For making calculations based on the available instruments to the causal LEAF operator (without LEAFSCAN, Consult XXXX, etc), it doesn't add up.

So, while I'm not disputing your source, 80 watt-hours has little meaning to that casual driver. I find it closer to 73-75 watts-hours of USEFUL, observed by the instruments in the vehicle, energy per Gid.
Keep in mind, all the instruments in the vehicle use this watt-hour figure (or the higher resolution version) for calculation of everything they display. So I respectfully disagree with you.

-Phil
 
Ingineer said:
TonyWilliams said:
Phil, I get that you are providing the data that Nissan has provided, and Im confident that it is very useful for many things. For making calculations based on the available instruments to the causal LEAF operator (without LEAFSCAN, Consult XXXX, etc), it doesn't add up.

So, while I'm not disputing your source, 80 watt-hours has little meaning to that casual driver. I find it closer to 73-75 watts-hours of USEFUL, observed by the instruments in the vehicle, energy per Gid.
Keep in mind, all the instruments in the vehicle use this watt-hour figure (or the higher resolution version) for calculation of everything they display. So I respectfully disagree with you.

-Phil

How do we account for, and resolve the discrepancies between the 80 published number and the 75 observed by the operator (me, and anybody with a Gidmeter) ?
 
I just charged to 100% after receiving my SOC meter a few ways ago. 256. Slightly alarming. Range has always seemed acceptable. We now have 14k miles and charged to 100% for the first 10-12k miles. Then, it dawned on me that 80% would suffice for most of our trips. We now charge to 100% only about once a week. Indicated range (trip distance plus SMRD reading) is 90-95 miles on a full charge. That makes maximum range (to turtle) 95-105 miles.

If the gid really represents energy in the battery, I am 10-12% low.
 
mckemie said:
I just charged to 100% after receiving my SOC meter a few ways ago. 256.
You may want to post your info in this thread also:

http://www.mynissanleaf.com/viewtopic.php?f=31&t=8331" onclick="window.open(this.href);return false;
 
TonyWilliams said:
Ingineer said:
TonyWilliams said:
Phil, I get that you are providing the data that Nissan has provided, and Im confident that it is very useful for many things. For making calculations based on the available instruments to the causal LEAF operator (without LEAFSCAN, Consult XXXX, etc), it doesn't add up.

So, while I'm not disputing your source, 80 watt-hours has little meaning to that casual driver. I find it closer to 73-75 watts-hours of USEFUL, observed by the instruments in the vehicle, energy per Gid.
Keep in mind, all the instruments in the vehicle use this watt-hour figure (or the higher resolution version) for calculation of everything they display. So I respectfully disagree with you.

-Phil

How do we account for, and resolve the discrepancies between the 80 published number and the 75 observed by the operator (me, and anybody with a Gidmeter) ?

how are you measuring this Tony? i see it wind down from 280 every morning and that is all the info i get from it. sometimes its every .2 miles or .3 or whatever. but other than that, i have no way of knowing if its 80 watts or any other wattage?
 
Unless you plan to violate the second law of thermodynamics, wh/gid must be higher going in than coming out. I get 80 going in and ~75 coming out (more noise in the measurement during discharge). Does this not explain the discrepancy?
 
TickTock said:
Unless you plan to violate the second law of thermodynamics, wh/gid must be higher going in than coming out. I get 80 going in and ~75 coming out (more noise in the measurement during discharge). Does this not explain the discrepancy?

ok so its "usable" charge. ok that makes sense since some is lost to heat both going in and out. so we *might* have 85 watts per GID coming in, 75 watts per GID going out. the rest NOT USED to warm our butts?
 
Boomer23 said:
For March:
Overnight temps typically around 50 deg F. All charging done beginning 12:10 am.

Almost all charging done to 100%. Full charges done so far in March = 16

LEAF delivered March 30, 2011

Miles at end of day March 25, 2012 = 11,105

Gids at 100% charge....starting Gids before charging
280....135 March 6
281....109 March 8
281....140 March 10
269....28 March 11
280....101 March 14
281....196 March 15
281....54 March 16
279....127 March 17
275....126 March 19
281....147 March 22
278....158 March 23
281....144 March 24
281....132 March 25
My experience is almost identical to Boomer's except that I have 15,500 miles in 10.7 months. So, I've gotten to 281 a little less frequently, but I still get there. This is after close to 300 charge cycles to 100% and driving 62 miles 5-6 days/week. But, starting last Friday, I've had a change in lifestyle. In fact, I haven't charged at all since Saturday morning (12:10 - 4:35 AM).
 
TonyWilliams said:
How do we account for, and resolve the discrepancies between the 80 published number and the 75 observed by the operator (me, and anybody with a Gidmeter) ?
I'm not seeing this. It is highly suspect of you to lump "everyone" in with you, when they have not confirmed this is the case. According to my measurements, and I have MUCH better instrumentation than you do, I see 80wh/Gid. I have confirmed this directly myself other cars as well, not just my own.

What are you basing this on? What the Miles/Kwh figure on the dash says? They do a lot of rounding, and it's very approximate, along with errors.

With a high accuracy, calibrated, galvanic current shunt installed in series with the battery, and connected using the kelvin method (4 wires), I have observed a reasonable accuracy for the overall power stored, with the exception of readings during correction periods. During these periods the car's power measurements appear skewed high until the correction event completes, and low afterwards. I suspect this is an attempt by Nissan to make the "average" more accurate. This affects all the car's visible instrumentation in different ways. The Leaf also exhibits a lot of error at low power levels as the current measuring system is hall-effect and subject to a number of effects that result in drift.

-Phil
 
By the way, the correction event after a charge is often why we see the GoM (and other car displays) show a more excessive consumption of energy initially.

-Phil
 
Ingineer said:
TonyWilliams said:
How do we account for, and resolve the discrepancies between the 80 published number and the 75 observed by the operator (me, and anybody with a Gidmeter) ?
I'm not seeing this. It is highly suspect of you to lump "everyone" in with you, when they have not confirmed this is the case. According to my measurements, and I have MUCH better instrumentation than you do, I see 80wh/Gid. I have confirmed this directly myself other cars as well, not just my own.

What are you basing this on? What the Miles/Kwh figure on the dash says? They do a lot of rounding....l


EXACTLY!!!! No, I not "clumping" anybody, since I'm not the only one with the 75 observation. Just read back through the posts. I clipped off your comments about how it can be done, because those are not the tools available to us in the pre LEAFSCAN world.

So, what I proposed in an earlier post (maybe on another thread) was that we cease the debate, and just present the data as advertised: Nissan says 80 watt/hours, so let's just call it watt/hours.

Then, what we observe during the propulsion of the car, using the same number who's value is based off the dash instruments; let's call those Gids. Yes, tons of rounding, lack of mega top secret accuracy, but those are the tools given us, and the results factored from those tools, and the math that works for the observed performance, and specifically not from lab work.

Does that work ?
 
TonyWilliams said:
Then, what we observe during the propulsion of the car, using the same number who's value is based off the dash instruments; let's call those Gids. Yes, tons of rounding, lack of mega top secret accuracy, but those are the tools given us, and the results factored from those tools, and the math that works for the observed performance, and specifically not from lab work.
Yes, and please don't forget losses, such as heat developed when storing and retrieving energy from the battery, and the energy lost during cell balancing. I believe that both are unaccounted for, and they will be missing from the equation if you assume 80 Wh will be going in and out of the battery. Sure, you can ignore them, and adjust for that error later, but this energy is lost, and you will ultimately see the effect one way or another. Even without instrumentation. Yes, it's old school and much tougher, but if there a sizable error, it can and will be detected by a careful observer.
 
surfingslovak said:
Yes, and please don't forget losses, such as heat developed when storing and retrieving energy from the battery, and the energy lost during cell balancing. I believe that both are unaccounted for, and they will be missing from the equation if you assume 80 Wh will be going in and out of the battery. Sure, you can ignore them, and adjust for that error later, but this energy is lost, and you will ultimately see the effect one way or another. Even without instrumentation. Yes, it's old school and much tougher, but if there a sizable error, it can and will be detected by a careful observer.
The watt-hours are "usable output", so they are corrected. (constantly in fact, as battery parameters are always in flux)

-Phil
 
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