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Re: Real SOC (State of Charge) - Information

Posted: Tue Mar 20, 2012 8:21 am
by garygid
So, what does consistantly getting 240 GIDs (instead of 280) after a full "100%" charge mean (on a "new" car)?

Is it really a car with 14% less battery pack capacity?

Since the Nissan dealer tech says the car is "fine", and the owner seems to get "normal" Range ... (do I have that correct?) ... is it more likely to be an incorrectly calibrated current or voltage sensor that leads to not reporting and calculating enough GIDs?

Either the owner got a low-capacity battery, or some sensor or calculation is wrong?

Could there be another way to explain the low (240) GID value?

Re: Real SOC (State of Charge) - Information

Posted: Tue Mar 20, 2012 8:23 am
by TickTock
Yes. When I plot energy vs gids, there is a lot of noise although the average step size comes to ~80wh (when charging). Can't say with certainty which is the noisy signal, the battery amps signal, battery volts signal, and time stamp or the Available Charge signal (gids). My guess is the former and the Available Charge signal is exactly what it's name implies. Phil wants more resolution so maybe we can figure out a way to fold in the measured battery power using gids as the framework.

Re: Real SOC (State of Charge) - Information

Posted: Tue Mar 20, 2012 8:26 am
by TickTock
garygid wrote:So, what does consistantly getting 240 GIDs (instead of 280) after a full "100%" charge mean (on a "new" car)?

Is it really a car with 14% less battery pack capacity?

Since the Nissan dealer tech says the car is "fine", and the owner seems to get "normal" Range ... (do I have that correct?) ... is it more likely to be an incorrectly calibrated current or voltage sensor that leads to not reporting and calculating enough GIDs?

Either the owner got a low-capacity battery, or some sensor or calculation is wrong?

Could there be another way to explain the low (240) GID value?
Based on the power measured at the wall, I think it means my battery really does have ~14% less capacity. The dealer said the CLVI indicated it was fine (only 60mV max-min) however, they still have it and my phone tells me they've charged and discharged twice so they are still looking.

Re: Real SOC (State of Charge) - Information

Posted: Tue Mar 20, 2012 8:43 am
by edatoakrun
TickTock wrote:
garygid wrote:So, what does consistantly getting 240 GIDs (instead of 280) after a full "100%" charge mean (on a "new" car)?

Is it really a car with 14% less battery pack capacity?

Since the Nissan dealer tech says the car is "fine", and the owner seems to get "normal" Range ... (do I have that correct?) ... is it more likely to be an incorrectly calibrated current or voltage sensor that leads to not reporting and calculating enough GIDs?

Either the owner got a low-capacity battery, or some sensor or calculation is wrong?

Could there be another way to explain the low (240) GID value?
Based on the power measured at the wall, I think it means my battery really does have ~14% less capacity. The dealer said the CLVI indicated it was fine (only 60mV max-min) however, they still have it and my phone tells me they've charged and discharged twice so they are still looking.
So, you have had the same reduced capacity (and range) since delivery, and this is the first time Nissan has looked at it?

Re: Real SOC (State of Charge) - Information

Posted: Tue Mar 20, 2012 9:00 am
by TickTock
Yeah. I was in denial for a long time. Only recently got confirmation that a gids was the same for me as everyone else (I was hoping my gids were bigger then yours :)). Also there was a lot of noise in the from-the-wall data with people questioning the accuracy of Blink or TED if lots of line noise was present, etc.

Also, I have been charging to 80% and getting 215-230 gids which is pretty close to what everyone else gets for 80% so my range at 80% hasn't been impacted - I only see it when I charge 100%.

Re: Real SOC (State of Charge) - Information

Posted: Tue Mar 20, 2012 9:10 am
by DaveinOlyWA
great conversation and it is interesting what various people's needs are.

afaic; i am with Phil. the more instantaneous feedback i get, the more i get to know the car. i have already learned a lot just from using the GOM as bad as it but it has given me some insight as to how my actions correlate to the car.

now with the SOC meter, i have learned new things and my ability to determine what i can do with the car has improved and i think that will also get better with the LEAFSCAN

as far as a DTE? dont need it. the Prius has one. i also ignore it as well. it normally started out at 525-565 or so and i normally put 450-500 miles on it so like whatever

Re: Real SOC (State of Charge) - Information

Posted: Tue Mar 20, 2012 10:16 am
by vegastar
TickTock wrote: Also, I have been charging to 80% and getting 215-230 gids which is pretty close to what everyone else gets for 80% so my range at 80% hasn't been impacted - I only see it when I charge 100%.
You have only 10 gids between a 80% charge and a 100% one? How many volts do you have in the CV phase of charging to 100% and at what voltage your 80% charges terminate?

Mine are 394V for 100% and 388,5V for 80%, and after charging they drop to 393V and 385,5V.

Re: Real SOC (State of Charge) - Information

Posted: Tue Mar 20, 2012 5:53 pm
by TickTock
vegastar wrote:
TickTock wrote: Also, I have been charging to 80% and getting 215-230 gids which is pretty close to what everyone else gets for 80% so my range at 80% hasn't been impacted - I only see it when I charge 100%.
You have only 10 gids between a 80% charge and a 100% one? How many volts do you have in the CV phase of charging to 100% and at what voltage your 80% charges terminate?

Mine are 394V for 100% and 388,5V for 80%, and after charging they drop to 393V and 385,5V.
Not really. 239 was what I was getting when I first got my SOC meter in October. It has increased somewhat over the winter and now I get 255+/- for 100% and 215+/- for 80%. Interestingly, my voltages are identical. For 80%, I get 387-391 and for 100% I get exactly 394 every time (no variation).

Got an update from the dealer earlier today. They have acknowledged that my range does seem to be lower then it should. They ran side by side test with their demo starting with 100% charge and after 39 miles, my car had 35 miles remaining on the GOM and theirs had 53. Sent logs to Osaka to analyze. So one more piece of evidence that gids really are a measure of available charge (just to show this really isn't off-topic :)).

Re: Real SOC (State of Charge) - Information

Posted: Tue Mar 20, 2012 6:02 pm
by Stoaty
TickTock wrote:Got an update from the dealer earlier today. They have acknowledged that my range does seem to be lower then it should. They ran side by side test with their demo starting with 100% charge and after 39 miles, my car had 35 miles remaining on the GOM and theirs had 53. Sent logs to Osaka to analyze. So one more piece of evidence that gids really are a measure of available charge (just to show this really isn't off-topic :)).
They had to drive two cars 39 miles in order to figure out there was a problem??? I would have thought their fancy equipment would tell them in a heartbeat if there was a problem with the battery.

Re: Real SOC (State of Charge) - Information

Posted: Tue Mar 20, 2012 7:07 pm
by mdh
Stoaty wrote:
TickTock wrote:Got an update from the dealer earlier today. They have acknowledged that my range does seem to be lower then it should. They ran side by side test with their demo starting with 100% charge and after 39 miles, my car had 35 miles remaining on the GOM and theirs had 53. Sent logs to Osaka to analyze. So one more piece of evidence that gids really are a measure of available charge (just to show this really isn't off-topic :)).
They had to drive two cars 39 miles in order to figure out there was a problem??? I would have thought their fancy equipment would tell them in a heartbeat if there was a problem with the battery.

This is very interesting... thanks for updating us. I really think Nissan is making a mistake by not publicly stating they will offer a sensible battery refresh program down the road. Great way to build customer loyalty.