SOC Guage on vehicle?

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rav4evdriver

Member
Joined
Feb 25, 2017
Messages
7
Is there any way to get a real time SOC gauge reporting on the Bolt? I can see the SOC reported on the "My Chevrolet" app. While it is good it is on an app, it would be ever so much more helpful if it was able to be reported on the vehicle while driving.

What would it take to get this feature added-if there is not a way to do this now?

Thank you,

Larry
 
There is an approximate SoC gauge, in that there are 20 'bars' that show amount of charge. But it is only "closest 5%". (Of course, traditional gas gauges are only about 1/8 to 1/16 "accurate", so ...)
 
Thank you.
It would be far more useful to have a 1% gauge...a 5% gauge with such a big battery is far too coarse.

Still looking for the data that is clearly there-because it is on the app...I just want that on the dash.
 
rav4evdriver said:
It would be far more useful to have a 1% gauge...a 5% gauge with such a big battery is far too coarse.
...I just want that on the dash.

This is one of the upgrades Nissan did between the 2011-2012 and later Leafs. They added a 1% read out of SOC on the dashboard. Dash would be better, but center console would be OK as well.
 
rav4evdriver said:
Thank you.
It would be far more useful to have a 1% gauge...a 5% gauge with such a big battery is far too coarse.

Still looking for the data that is clearly there-because it is on the app...I just want that on the dash.


Almost hand in hand with kWh used. It's more accurate that 1%. Between the battery ( driver side console) and kWh used. 60kwh battery minus what you have used =SOC. Sorry you have to subtract a little but it works for me.
 
While that can work with a full charge every time, it does not help at all when I charge not to full and charge only occasionally.

The car has the data... (because the app reports it). Adding that to one of the screens seems like a simple thing that GM would want to give the users of the car. SOC on an ev is far more useful to me and I suspect many others than a GOM (guess-o-meter)-exclusively.

It should be at least an option on the advanced screen on the speedo cluster in front of the driver...but at least on the energy screen on the center stack would work (but less ideal).
 
Posatronic said:
rav4evdriver said:
Thank you.
It would be far more useful to have a 1% gauge...a 5% gauge with such a big battery is far too coarse.

Still looking for the data that is clearly there-because it is on the app...I just want that on the dash.


Almost hand in hand with kWh used. It's more accurate that 1%. Between the battery ( driver side console) and kWh used. 60kwh battery minus what you have used =SOC. Sorry you have to subtract a little but it works for me.

Not really. That assumes

1.. The battery started fully charged, and
2. The battery still retains its original capacity.

In general, neither will be true. What would be even more useful is a kWh remaining display.
 
rav4evdriver said:
Is there any way to get a real time SOC gauge reporting on the Bolt? I can see the SOC reported on the "My Chevrolet" app. While it is good it is on an app, it would be ever so much more helpful if it was able to be reported on the vehicle while driving.

What would it take to get this feature added-if there is not a way to do this now?

Thank you,

Larry

Hi Larry,

Unfortunately at this time, this information is not able to be displayed on your dash at this time. I have however, made sure to document your suggestion, along with the additional feedback others have posted, within my internal systems. This will allow our internal development teams the opportunity to review your input.

Please let us know if you have additional questions, comments or concerns.

Kind Wishes,

Amber G.
Chevrolet Customer Care
 
Amber,

Thank you. Please do add this to the list of "feature requests". The Bolt is exceptionally well engineered, but having access to the SOC is very useful for drivers that are looking to maximize the driving experience. The range of the car is excellent, but the guess-o-meter does not really consider future driving conditions (weather, elevation changes, road conditions) that the driver IS aware of, but the car is not. This is why the SOC is more useful. I have found that I do not have to charge but every few days and when I do charge, it is often not to full.

This is a mockup of where I think it could go on the dash - under the "Enhanced" dash layout.

SOC example small.jpg

Thank you,

Larry



Total miles my wife and I have put on battery power since January 1999 to date: <239,500 miles.

2017 Chevy Bolt (December 2016 to date)
2013 Chevy Volt (November 2012 to date)
2011 Nissan Leaf (July 2011-November 2012)
2002 Rav4EV (August 2002 to date)
1999 Honda EV Plus (January 1999-December 2003)

Plus a few of my interesting conventional cars owned
1995 Saab Aero (May 1995 to date)
1965 Sunbeam Tiger (1981 to date)
1989 SHO Taurus (March 1989-May 1995)
1975 Cosworth Vega (1985-1994)
 
kWh remaining (with one decimal place) would be better than a percentage. It provides more precision, and it won't change scale as the battery degrades.

Cheers, Wayne
 
I agree with that comment. Percentage I have for my other cars is based on total capacity including degradation, meaning an aged battery would show 94% at full charge for example.

If an add can be made, the enhanced screen could/should enable selection of either % of capacity (compared to a new pack) or in kWh remaining.

Best regards,

Larry
 
As it happens, Estimating the state of charge of a Lithium battery is quite difficult. You can't measure it directly - SoC is an engineering construct composed of a lot of fixed and variable factors.
Measurement requires precision of hundredths of a volt, which is the only relevant thing you can actually measure. However, the voltage of cells is affected not just by the charge, but also by their temperature and by any other non-measurement part of the car that is connected at that time, and also is dependent on the increase in resistance of the cells themselves. In a Bolt, there is literally always some part of the car active to some degree.
Bottom line is that any figure in 1% increments would be inaccurate. The current 5% increments are good enough "for all practical purposes," as they say, and probably represents the uncertainty in the SoC Estimate anyway.
 
EldRick said:
As it happens, Estimating the state of charge of a Lithium battery is quite difficult. You can't measure it directly - SoC is an engineering construct composed of a lot of fixed and variable factors.
Measurement requires precision of hundredths of a volt, which is the only relevant thing you can actually measure. However, the voltage of cells is affected not just by the charge, but also by their temperature and by any other non-measurement part of the car that is connected at that time, and also is dependent on the increase in resistance of the cells themselves. In a Bolt, there is literally always some part of the car active to some degree.
Bottom line is that any figure in 1% increments would be inaccurate. The current 5% increments are good enough "for all practical purposes," as they say, and probably represents the uncertainty in the SoC Estimate anyway.

It requires some sophistication but it is done all the time.

Texas Instruments is a leader in the field. Description of their products can be seen here

http://www.ti.com/lsds/ti/power-management/battery-fuel-gauge-overview.page

These are intended for small devices, but the principles are the same. I'm confident the Bolts internal computers have all these numbers...they are not displayed as a matter of Chevy's choice.

Your comments about temperature, load, internal resistance, etc. are correct. However modern techniques provide compensation for these factors when estimating SOC. My Focus Electric had it years ago. You could read out (over the OBD II bus) SOC and kWh remaining as well as cell voltages and battery temperature.
 
We read it out from the Leaf's Can Bus too, using LeafSpy. It's invaluable information when you're traveling and running low and calculating wether you can make your destination or not. All EVs should offer it. But probably someone will develop BoltSpy and we'll get the information we need that way. Pack temp and cell balance are also important.
 
DNAinaGoodWay said:
probably someone will develop BoltSpy and we'll get the information we need that way.

I don't see any significant value that could be added by a BoltSpy. As noted above, SOC is already available to within 1% in the mychevrolet app.

I agree that a dashboard SOC with 1% precision would be better. Why withhold that data from drivers, or make us use a phone app while we're supposed to be focused on our driving? Disclaim accuracy if appropriate, but give us the best data you can. However, the current graphical display with 5% precision seems to me adequate for almost all practical purposes, so for me this is only a minor annoyance.
 
I'd much prefer it on the dash. Yet they don't. Don't they know how geeky we are?

The trouble comes when you're very low, and the dash display just flashes "low" or in the Leaf "---". This tells us nothing useful about our probability of making our destination.
 
Does the MyChevrolet communicate directly with the vehicle (i.e., effectively immediately?) or does it work like the old Remote Link that contacts Onstar? That takes way too long to respond to be very useful.
 
Amber and community:

In further contemplation, here are two probably better layouts that I think would be the ideal that are to be considered under "enhanced":

One as SOC (% remaining), the other as KWh remaining.


SOC example small2 SOC.jpg

SOC example small2 KWh.jpg
 
If the concern is whether you can make those last 15 miles, I would never rely on a charge estimate to be accurate.
When a lithium battery comes near the bottom of its charge, voltage drops like a stone, and is even less predictable than usual because of the steep slope of the curve.
 
It doesn't work that way. An electric car is not like a flashlight that goes suddenly dim. It's not like a gas car that runs out of gas when the pickup in the gas tank isn't submerged. An electric car is empty when the computer decides it's empty. It knows exactly when it's going to declare itself empty.

Ampere-hours are conserved. The computer knows how many Ampere hours are left in the battery. It doesn't go by Voltage alone.
 
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