Two identical sparks, 2 very different range estimates...

[CSW]

I own 2 sparks, a 2015 and a 2016. Same battery. The 2016 shows about 87 miles of range and the 2015 shows 67 miles when fully charged. They are the same car, same charging, same temperature, both have had the range meter update done. It is almost like the 2015 has a dead part of the battery, I have seen the Spark battery & it is like 6 parts, maybe one is a dud and dead?? So what gives?? Any ideas? I don't want to go to the deal as they will just say "it is fine".

 

[scrambler]

What number do you get for each when you calculate the usable battery capacity from the % battery used and kWh used in the leaf screen, taking these number after more than 50% of the battery has been used.

For example, if when it says 76% used and 11.8 kWh used. it would mean the usable battery capacity is around 11.8 / .76 =15.5 kWh

 

[NORTON]

I'm not going to post what my GOM shows these cold days.

I use heat freely, (the way I get my charge ), and I hang with my buds in the left lane of rush hour interstate travel, 70-80+ MPH. Sometimes bump the 90 limiter.

Hang in there. After the sacrifice on Dec 21 the days will get longer and eventually temps will warm up. It happens every time !! (Causation)

 

[CSW]

What number do you get for each when you calculate the usable battery capacity from the % battery used and kWh used in the leaf screen, taking these number after more than 50% of the battery has been used.

For example, if when it says 76% used and 11.8 kWh used. it would mean the usable battery capacity is around 11.8 / .76 =15.5 kWh

Thanks for this tip, I think I can follow those instructions. I will get both cars done and report back in a couple days... I have never checked this before.

 

[CCIE]

I own 2 sparks, a 2015 and a 2016. Same battery. The 2016 shows about 87 miles of range and the 2015 shows 67 miles when fully charged. They are the same car, same charging, same temperature, both have had the range meter update done. It is almost like the 2015 has a dead part of the battery, I have seen the Spark battery & it is like 6 parts, maybe one is a dud and dead?? So what gives?? Any ideas? I don't want to go to the deal as they will just say "it is fine".

Who drives each of them, where/how do they drive, are the same climate control settings used? Driver and climate settings make a huge difference.

 

[CSW]

I am just talking about the range displayed when each has been fully charged. This can be affected by driving style?? What difference would that make? But to answer the question, the 2015 showing low range is driven 50 miles a day commuting and then fully charged again each day. The 2016 with more range is driven more variably with no set routine and then fully charge every day as well. The 15 has 24k miles on it and the 16 has 13k miles on it.

 

[Planerench]

Oh yeah, the car uses past conditions to guess the range in the future!

 

[CSW]

Oh yeah, the car uses past conditions to guess the range in the future!

Hm. Yes, true, maybe that is it? The 2015 is always driven the same pretty much. Hhhmmmm. Interesting.

 

[Taxman]

Assume two identical cars with two different drivers, with 15 kWh of usable battery capacity.

One drives at high speeds a lot, uses the heaters a lot and frequently brakes hard enough to engage the hydraulic brakes, and gets 3 miles per kWh. The other tries to preheat the car while it's plugged in and makes heavier use of regenerative braking, rarely goes over 50mph, and gets 5 miles per kWh. Would we be surprised if the first driver's car predicted 45 miles of range and the second driver's car predicted 75 miles?

 

[scrambler]

I am just talking about the range displayed when each has been fully charged. This can be affected by driving style?? What difference would that make?

It does make all the difference, as the range is estimated based on the performance (miles/kWh) of the last few days of consumption.
Basically, the estimated range value is based on two parameters. The battery usable capacity (discussed previously), and how many miles per kWh you usually achieve based on your driving conditions (terrain, temperature, speed, heater, driving style...).
Estimated range = Bat capacity x Miles/kWh

Depending on the driving conditions , you can achieve between around 4 miles per kWh and 6 miles per kWh.
The nominal usable capacity of a spark is around 18.5kWh (could be less with age).

With a battery capacity of 18.5 kWh, the two extremes of the miles per kWh mentioned above translate to a range between 74 miles (4 x 18.5) and 111 miles (6 x 18.5)
If the battery has degraded and is only 15.5 kWh that would be between 62 miles (4 x 15.5) and 93 miles (6 x 15.5)

The miles per kWh (resulting of your driving conditions) which is used to estimate the range, is the average miles per kWh of the last few days.
So if you want to see if the difference in estimated range comes from the driving conditions of the two cars, display the trip information which shows the average miles per kWh, and reset it on both cars. Then after 4 days of driving, check the miles per kWh value displayed on each car.
That will give you one half of the puzzle (the other half being the battery usable capacity I mentioned in my first answer).

Note: This is actually another way to estimate the battery capacity.
For example, if a car consistently shows 67 miles of estimated range after a full charge, and if the average miles/kWh is consistently around 4 miles per kWh, it would indicate that the usable battery capacity is 67 / 4 = 16.75 kWh.

 

[CCIE]

Switch cars for a week or two. I bet you see the estimated mileage numbers swap.

 

[CSW]

Thanks for all the good info. I think my wife is more of a leadfoot than me it seems.... she has said she likes the speed
of the Spark.

I got the numbers on the 2015 spark showing the lower range estimate today:

After a 50 mile trip, shows 63% used and used 10.4kwh (53% driving and 10% climate control) = so 16.50kwh useable battery??

Isn't that low? The car only has 24k miles on it. That is about 87% of the full 19kwh, but I guess the battery never gets fully used anyways?

Also, checking the trip meter, shows average of 4.1kwh/mi for the last 500 miles all with just same commuting really.

So putting that together, that means 4.1mi/kwh x 16.5 useable = 67 miles range? Loooow.

I will get the numbers on the higher 2016 car tomorrow or next day.
Checking the trip meter, I am getting 4.6mi/kwh average, so higher there already.
So assuming it had 16.5 like the 2015, range would be 76 miles....
but the range meter often shows much more than that........we shall seeeee.....

 

[MrDRMorgan]

Thanks for all the good info. I think my wife is more of a leadfoot than me it seems.... she has said she likes the speed
of the Spark.

I got the numbers on the 2015 spark showing the lower range estimate today:

After a 50 mile trip, shows 63% used and used 10.4kwh (53% driving and 10% climate control) = so 16.50kwh useable battery??

Isn't that low? The car only has 24k miles on it. That is about 87% of the full 19kwh, but I guess the battery never gets fully used anyways?

Also, checking the trip meter, shows average of 4.1kwh/mi for the last 500 miles all with just same commuting really.

So putting that together, that means 4.1mi/kwh x 16.5 useable = 67 miles range? Loooow.

I will get the numbers on the higher 2016 car tomorrow or next day.
Checking the trip meter, I am getting 4.6mi/kwh average, so higher there already.
So assuming it had 16.5 like the 2015, range would be 76 miles....
but the range meter often shows much more than that........we shall seeeee.....

One of the problems with trying to calculate the HV battery capacity by using the information on the Energy Information screen, is you do not know how much regeneration energy resulting from driving in L and / or braking was added back into the battery. What I do know is adding charge back into the battery will cause the DRIVE value to decrease while the kWh value remains the same. This results in a calculated battery capacity value higher that the actual value. To verify this, I recorded the DRIVE and kWh values shown on the Energy Information screen in my 2016 Spark EV. I then connected the car to my L2 EVSE and charged for about 2 hours. The DRIVE value decreased from 62% to 50%. The kWh value did not change.

I believe a more accurate battery capacity value can be obtained by driving the car in D, at a steady speed - no braking - on a flat road, no head wind or tail wind, for 20-30 miles. Record the DRIVE value and kWh value at the start and end of the drive. Subtract the starting values from the ending values and use the results to calculate your HV battery capacity. I tried this a few weeks ago and it seemed to work well. One key is to not do anything to cause energy regeneration.

 

[CSW]

" Subtract the starting values from the ending values "
What does this mean?
Also, HV? What that? ____ value?

I will try to drive like you are saying for about 30 miles in my 2016 tomorrow.
I think I can pull it off.

I am really curious about this because I am going to buy one of my Sparks at the end of the lease, and if one
gets like 20 miles more range, I would get that one of course.

 

[CCIE]

If you want to know the true battery capacity, you'll need to buy a VCX Nano GM from Amazon for $130 and use the included GDS2 to look at the actual number. You'll also need some computer skill and a windows laptop to do that.

But, if the cars are still getting enough range for your normal use, I would just drive them and not worry about it.

 

[MrDRMorgan]

" Subtract the starting values from the ending values "
What does this mean?
Also, HV? What that? ____ value?

I will try to drive like you are saying for about 30 miles in my 2016 tomorrow.
I think I can pull it off.

I am really curious about this because I am going to buy one of my Sparks at the end of the lease, and if one
gets like 20 miles more range, I would get that one of course.

The Energy information screen [press the LEAF button] only resets to zero when you fully charge the car. But, there is no reason why you have to fully charge to run the test. You just need to have sufficient capacity in your battery to run the test with some reserve left over.

Just before you leave for the test trip, press the LEAF button, press Energy Information, then press ENERGY DETAILS and record the DRIVE % and the kWh Used values. Then go drive your test trip so almost no regenerated energy is added back into the battery [use the cruise control, drive in D and stay off of the brakes, flat road, etc.]. At the end of your trip again press the LEAF button, press Energy Information, then press ENERGY DETAILS and record the DRIVE % and the kWh Used values. Subtract the starting DRIVE % from the ending DRIVE % to get the change in DRIVE %. Subtract the kWh Used value at the start of the trip from the kWh Used value at the end of the trip. Then divide the change in kWh Used by the change in DRIVE % [expressed as a decimal] to calculate your estimated HV battery capacity. If you fully charge before you start the test, you only need to use the Energy Details you record at the end of the test since the starting values are all zero.

I tried this in September and got the following results:
2014 Spark EV [11332 miles on the ODO]: Calculated battery capacity was 18.0 kWh
2015 Spark EV [20845 miles on the ODO]: Calculated battery capacity was 17.1 kWh.

Let me know how this works for you.

HV means High Voltage referring to the High Voltage traction battery [~400 volts] in the car.

Note: I just purchased a used 2016 Spark EV [6700 miles on the ODO] to replace my 2015 Spark EV when the lease ends in May next year. I purchased my 2014 Spark EV in August of 2015. It was used with only 1500 miles on the ODO.

 

[NORTON]

As has been said, that display is just the Guess-O-Meter.
It has no way of knowing how you will be driving the car this day, only how it was driven recently.

Only the leaf page gives battery capacity when you do the math.
Or you can use more expensive diagnostic equipment.

 

[scrambler]

What I do know is adding charge back into the battery will cause the DRIVE value to decrease while the kWh value remains the same. This results in a calculated battery capacity value higher that the actual value. To verify this, I recorded the DRIVE and kWh values shown on the Energy Information screen in my 2016 Spark EV. I then connected the car to my L2 EVSE and charged for about 2 hours. The DRIVE value decreased from 62% to 50%. The kWh value did not change.

I don't know about additional charging with the EVSE, but this is not my experience with regen.

If the car shows a % used and a kWh used and I get a lot of regen, both the % and the kWh used will go back down. So I don't think Regen affects the accuracy of that reading

 

[MrDRMorgan]

What I do know is adding charge back into the battery will cause the DRIVE value to decrease while the kWh value remains the same. This results in a calculated battery capacity value higher that the actual value. To verify this, I recorded the DRIVE and kWh values shown on the Energy Information screen in my 2016 Spark EV. I then connected the car to my L2 EVSE and charged for about 2 hours. The DRIVE value decreased from 62% to 50%. The kWh value did not change.

I don't know about additional charging with the EVSE, but this is not my experience with regen.

If the car shows a % used and a kWh used and I get a lot of regen, both the % and the kWh used will go back down. So I don't think Regen affects the accuracy of that reading

On Friday I will be driving over a couple of passes where the downhill side does generate considerable regen as I drive in L. I'll try to remember to note the DRIVE % and kWh Used values at the top and bottom to see how the DRIVE and kWh values change. I'll report my findings on Saturday.

Update: This afternoon, I decided to re-test my 2015 Spark EV using the same route as I did in September. I drove on the freeway with the cruise control set to 60 mph. I also configured the display to show any regeneration. I actually had a little regeneration due to overpasses, under passes, and slowing down for traffic but not a amount to be significant. I drove 35.47 miles at an average of 5.6 mi / kWh [6.33 kWh consumed]. The Energy Information screen for DRIVE read 40% at the end of my drive. The calculated HV battery capacity is 15.83 kWh which is almost 1.3 kWh lower than my September calculation and is consistent with a recent problem with the car.

In late October the yellow "Service Vehicle Soon" light came on. I took the car to the dealer and they said there was a problem with the DC charging unit so a repair part was ordered. So far, the part has not arrived. When I got the car back, the light was out, and has remained out, but my battery capacity took a hit and today's calculation is consistent with the drop in full-charge range I have been seeing. I will have to wait to see if the repair part fixes the problem or the dealer finds the problem is really with the HV battery.

 

[CSW]

Did the test today on the higher-range 2016.
Drove about 30 miles on the freeway with almost no re-gen.

Came out to used 67% and 11.9kwh.
So 11.9 / .67 = 17.8 kwh usable battery

So when compared to the 2015 spark, the 2016 is showing about 1.5kwh MORE that the 2015 usable at 16.5kwh.

And this is with the lower 2015 Spark number showing some re-gen as half of the 50 mile commute is thru the city with
many stoplights, so the 2015 maybe be ever less than 16.5?? Because it is adding kw during the commute?