SageBrush
Posts: 1423
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Battery Percent Indicator

Sat Nov 04, 2017 1:55 am

cwerdna wrote:
SageBrush wrote:
cwerdna wrote:I couldn't care less about the what claimed kWh values are.

Whatever. Just assume default Gid/Wh

Sure. I suspect most Leaf Spy users don't know about the setting and thus are using the default.

My issue is that with the default of 77.5 watt-hours/gid or whatever other value, we have no idea if the resulting kWh value is accurate at all. Unless you can tell me that Nissan has officially blessed that constant or given us conditions where the result is accurate (e.g. range of gid values where it's valid, battery temperature, battery condition, after certain things have been done or not done to the battery, etc.)...

It really bothers me that so many people are doing so much reading into and inference of values that Leaf Spy (e.g. gids, gids * Wh/gid, SOH and Hx, etc.) renders despite the fact that AFAIK, Nissan has never released any public documentation on them nor acknowledged any of them. Sure, we can compare notes, but to make assertions like "my battery holds x kWh" or 85% SOH must == 15% capacity loss, I'm not that comfortable with. Is it approximately right? Probably, most (?) of the time. Is it exact? Probably not, esp given the numbers move around a bit and can be manipulated a bit, as well.

The Gid and kWh numbers have a clearly relation to the battery voltage and Ahr. Are you skeptical of those too ?
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

cwerdna
Gold Member
Posts: 7188
Joined: Fri Jun 03, 2011 4:31 pm
Delivery Date: 28 Jul 2013
Location: SF Bay Area, CA

Re: Battery Percent Indicator

Sat Nov 04, 2017 8:27 am

SageBrush wrote:The Gid and kWh numbers have a clearly relation to the battery voltage and Ahr. Are you skeptical of those too ?

Gids have no units other than the unit named in GaryGid's honor. Who knows what the Nissan internal name is? I'm not particularly skeptical of gids other than to look at them as a unit-less value that we can use as a proxy for a finer grained state of charge value where the max also decreases as the battery degrades. To start assigning a constant of 77.5 watt-hours/mile then multiply to result in kWh I'm somewhat skeptical of.

For all we know, Nissan's internal documentation could say something like, this value is not valid outside of a certain numeric range or, it's only valid between certain temps or after a ___ discharge cycles down to ____ and then to full. Or, between x and y gids, you should use z constant. Between and and b gids, you should use c constant. Or, there are known quirks below d gids or above e gids.

The Ahr figure could have similar caveats about pre-conditions.

I'm not particularly skeptical about cell or pack voltages based on known specs of the pack and cells. I haven't followed all the CAN related work, but I'd imagine work like at viewtopic.php?f=8&t=17470 further confirms the voltage values being rendered at the cell level. I don't know how accurate those sensors are, but it doesn't really matter that much for many/most Leaf Spy users.

It is useful to compare notes about figures like SOH, Hx, AHr and # of gids on a full charge to help determine how close someone is to losing a/another bar.

'13 blue Leaf SV w/premium package (owned)
'13 blue Leaf SV w/QC + LED & premium packages (lease over, car returned)
'06 Prius

johnlocke
Posts: 174
Joined: Fri Jan 08, 2016 3:47 pm
Delivery Date: 14 Dec 2015
Leaf Number: 300582

Re: Battery Percent Indicator

Sat Nov 04, 2017 8:43 pm

cwerdna wrote:
SageBrush wrote:The Gid and kWh numbers have a clearly relation to the battery voltage and Ahr. Are you skeptical of those too ?

Gids have no units other than the unit named in GaryGid's honor. Who knows what the Nissan internal name is? I'm not particularly skeptical of gids other than to look at them as a unit-less value that we can use as a proxy for a finer grained state of charge value where the max also decreases as the battery degrades. To start assigning a constant of 77.5 watt-hours/mile then multiply to result in kWh I'm somewhat skeptical of.

For all we know, Nissan's internal documentation could say something like, this value is not valid outside of a certain numeric range or, it's only valid between certain temps or after a ___ discharge cycles down to ____ and then to full. Or, between x and y gids, you should use z constant. Between and and b gids, you should use c constant. Or, there are known quirks below d gids or above e gids.

The Ahr figure could have similar caveats about pre-conditions.

I'm not particularly skeptical about cell or pack voltages based on known specs of the pack and cells. I haven't followed all the CAN related work, but I'd imagine work like at viewtopic.php?f=8&t=17470 further confirms the voltage values being rendered at the cell level. I don't know how accurate those sensors are, but it doesn't really matter that much for many/most Leaf Spy users.

It is useful to compare notes about figures like SOH, Hx, AHr and # of gids on a full charge to help determine how close someone is to losing a/another bar.

You have to start somewhere. Nissan has never released anything on the CAN bus network. The GID is just a number that happens to change with the state of charge of the battery. The value is what it is. You can actually assign the number of watt hours per GID in Leaf Spy. From the data I've accumulated, my best fit is 78.7. YMMV. For the owners of newer Leafs the percent charge screen is sufficient for everyday use. The GID value is most useful in determining battery degradation by noting its value after a full charge.

It is precisely the fact that Nissan doesn't release information that makes this all relevant in the first place. Nissan has played fast and loose with the capacity bars values and the guess-o-meter is a joke. Reverse engineering like Leaf Spy is necessary only because Nissan has refused to release to the public the data and values used to determine what those cute little bars mean. Would you have bought a 30KWH Leaf if you knew that the battery warranty didn't kick in until you lost 40% of capacity? Or would you have thought twice about it because of all the failures of batteries in older models? Do you like the Idea that you don't get any warning of capacity loss until you are down 20%? I expect a gauge to be reasonably accurate and linear unless I'm told differently. The current degradation gauge is little more than a glorified idiot light. Nissan designed it to fool you into thinking everything's fine until it;s too late.
Jamul, CA
San Diego East County

SageBrush
Posts: 1423
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Battery Percent Indicator

Sun Nov 05, 2017 12:49 am

johnlocke wrote:It is precisely the fact that Nissan doesn't release information that makes this all relevant in the first place. Nissan has played fast and loose with the capacity bars values and the guess-o-meter is a joke. Reverse engineering like Leaf Spy is necessary only because Nissan has refused to release to the public the data and values used to determine what those cute little bars mean. Would you have bought a 30KWH Leaf if you knew that the battery warranty didn't kick in until you lost 40% of capacity? Or would you have thought twice about it because of all the failures of batteries in older models? Do you like the Idea that you don't get any warning of capacity loss until you are down 20%? I expect a gauge to be reasonably accurate and linear unless I'm told differently. The current degradation gauge is little more than a glorified idiot light. Nissan designed it to fool you into thinking everything's fine until it;s too late.


My opinions exactly.
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

powersurge
Posts: 753
Joined: Wed Oct 21, 2015 10:24 am
Delivery Date: 06 Dec 2014
Location: Long Island, NY

Re: Battery Percent Indicator

Sun Nov 05, 2017 4:04 am

Firstly, I need to say ( as other have not) that the original poster has not been operating his Leaf correctly. If he drives the car DAILY down to the "second" alarm (which I would imagine I right before "turtle mode"), then he has been abusing and killing his battery since the day he got it. If he is only NOW getting Leafspy, then No wonder his battery is showing low numbers. His battery has been degraded daily for 19 months... I have never driven down to the alarms, and follow our accepted guideline for battery health with no issues.

I agree with the posts that say that Nissan's battery bar system is just a general "idiot light" and that it is not accurate. However, if all Leaf drivers have the same gauges, then we all have a common frame of reference that we can talk about and compare. Also, the Leafspy GID system has been a great diagnostic program for us to get much more sensitive (accurate) information about our cars.

I do not agree with people who are so obsessive about accuracy and numbers that they are STILL not happy and complain... does it matter to measure battery charge down to the milli watt? Before this car, did anyone ever worry how many miles of life were left on your gas car?? No. Totally unimportant. To those people I say.. Shut up, drive your car (however long it has left), and be happy.

Original poster... You have been too hard on your car, and your car will surely tell you this when the battery craps out....

cwerdna
Gold Member
Posts: 7188
Joined: Fri Jun 03, 2011 4:31 pm
Delivery Date: 28 Jul 2013
Location: SF Bay Area, CA

Re: Battery Percent Indicator

Sun Nov 05, 2017 4:35 am

^^^
You have the excellent lizard battery since you have a ‘15, not the apparently crappy 30 kWh battery. Also, you don’t live in a hot climate area. If you had a 30 kWh Leaf with the same build month and also lived in a hot climate, your tune would be different and the result would be similar to the OP’s. From OP’s Leaf Spy stats, they’ve got to be down 3 bars.

In hot climates with the lizard battery, those folks seem to be down only 1 or 2 bars at this point (viewtopic.php?f=30&t=24532). This differs from the horror show we’ve seen on more recently built ‘16 30 kWh cars. In mild climates, I'm currently unaware of any '15 capacity bar losers.

Is the deep cycling helping contribute to capacity loss? Yes, partially but I assert it’s the hot climate and crap 30 kWh batteries that are a bigger factor.

You’ve made numerous misleading and uninformed posts on MNL. Not sure what’s up with that.

'13 blue Leaf SV w/premium package (owned)
'13 blue Leaf SV w/QC + LED & premium packages (lease over, car returned)
'06 Prius

SageBrush
Posts: 1423
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Battery Percent Indicator

Sun Nov 05, 2017 8:34 am

powersurge wrote:I do not agree with people who are so obsessive about accuracy and numbers that they are STILL not happy and complain... does it matter to measure battery charge down to the milli watt? Before this car, did anyone ever worry how many miles of life were left on your gas car?? No. Totally unimportant. To those people I say.. Shut up, drive your car (however long it has left), and be happy.

I read this paragraph 3 times and I still have no idea what you are getting at, although it seems pretty reasonable to me for people to evaluate their cars during ownership for degradation.
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

johnlocke
Posts: 174
Joined: Fri Jan 08, 2016 3:47 pm
Delivery Date: 14 Dec 2015
Leaf Number: 300582

Re: Battery Percent Indicator

Sun Nov 05, 2017 2:30 pm

powersurge wrote:Firstly, I need to say ( as other have not) that the original poster has not been operating his Leaf correctly. If he drives the car DAILY down to the "second" alarm (which I would imagine I right before "turtle mode"), then he has been abusing and killing his battery since the day he got it. If he is only NOW getting Leafspy, then No wonder his battery is showing low numbers. His battery has been degraded daily for 19 months... I have never driven down to the alarms, and follow our accepted guideline for battery health with no issues.

I agree with the posts that say that Nissan's battery bar system is just a general "idiot light" and that it is not accurate. However, if all Leaf drivers have the same gauges, then we all have a common frame of reference that we can talk about and compare. Also, the Leafspy GID system has been a great diagnostic program for us to get much more sensitive (accurate) information about our cars.

I do not agree with people who are so obsessive about accuracy and numbers that they are STILL not happy and complain... does it matter to measure battery charge down to the milli watt? Before this car, did anyone ever worry how many miles of life were left on your gas car?? No. Totally unimportant. To those people I say.. Shut up, drive your car (however long it has left), and be happy.

Original poster... You have been too hard on your car, and your car will surely tell you this when the battery craps out....

First, Has Nissan ever mentioned that fully charging the newer 30 KWH battery is detrimental to it? Or that leaving it fully charged is bad for the battery? Has Nissan ever stated that you should avoid operating the car below VLBW? I don't recall the dealer mentioning it to me. I don't recall the owner's manual saying that it would damage the battery. I do recall that the manual stated that the battery had protections built in to prevent damage.

In short the OP has operated the car within Nissan's guidelines and is not abusing the battery as you accuse. NIssan's guidelines might be inaccurate or even harmful but that is Nissan's fault. Would you have bought the car if Nissan stated that the useable range was only 65 miles because you shouldn't charge it to over 80% and shouldn't let it discharge lower than 20%? I know that I wouldn't.

As far as the life of ICE cars go, we don't talk about how many miles are left but we do talk about reliability a lot. We know which models have poor reliability and avoid them or buy them at steep discounts. Why do you think used Leafs are so cheap? Everyone knows that the battery is crap and costs a fortune to replace. If the battery lasted forever and the rest of car was in decent shape, people would be paying a premium for it. Not Happening!
Jamul, CA
San Diego East County

bdgriner
Posts: 10
Joined: Wed Feb 24, 2016 7:41 pm
Delivery Date: 31 Jan 2016
Leaf Number: 300675
Location: Birmingham Alabama

Re: Battery Percent Indicator

Sun Nov 05, 2017 7:40 pm

When I changed to the 2016 Leaf, I thought a 30 kWh leaf would be able to handle a 75 mile Roundtrip daily commute. It had an advertised range of 107 miles. I based this on having a Chevy Volt for 3 years. It reliably provided 35 to 38 miles of range every day before the engine turned on. (10 kWh battery) This was in line with the advertised range. Over the 45K omiles I had the Volt, I couldn’t tell if the range changed. In the winter, it would drop a few miles and more if I used the heater. The car provided a kWh reading on the dashboard and provided a full 10 kWh everyday. Now with a degrading battery, my decision making based on my experience with the Chevy Volt was in error.

I looked closely at the battery gauge and its only down 2 bars for a SOH of 66%. Suspect I will be losing another one shortly.

cwerdna
Gold Member
Posts: 7188
Joined: Fri Jun 03, 2011 4:31 pm
Delivery Date: 28 Jul 2013
Location: SF Bay Area, CA

Re: Battery Percent Indicator

Sun Nov 05, 2017 9:29 pm

^^^
Yeah, I’ve heard numerous claims that Volt battery degradation is minimal likely due to thermal management and keeping state of charge within a smaller window. IIRC, you have around 6 KWh inaccessible if you combine the inaccessible bands at the top and bottom.

So far, 30 kWh Leaf batteries seem to be a disaster for those in hot climates, possibly as bad as or worse than the ones in pre-4/2013 built Leafs.

'13 blue Leaf SV w/premium package (owned)
'13 blue Leaf SV w/QC + LED & premium packages (lease over, car returned)
'06 Prius

Return to “Range / Efficiency / Carwings”