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Discussion Starter #1 (Edited)
So despite my urge to start driving this little torque beast like I stole it, I decided to do a max range test and get that out of the way before I started peeling out at stop lights (yes, the tires do chirp). ;) :cool:

Driving was performed with HVAC off, windows cracked (at times), and just the radio on over the last several days. This was actual real world (conservative) driving, not driving around in circles, and ended up being a 60/40 city/highway ratio, with speeds of 55 mph on the highway. Tire pressure was ~42 psi cold.

I think I could have eeked out another mile or 2 if I had run it all the way out of battery.
In city-only driving, I would have easily been able to get over 100 miles.

Now it's time to play the "What cars can I smoke at a light" game. :cool:

Interesting thing is the kWh used....17.7 kWh used and 98% battery utilization. That would mean about 18 kWh usable capacity if run to depletion.....from an 18.4 kWh pack. That would mean almost 98% depth of discharge!

 

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Discussion Starter #3
Yep, picked it up last Thursday.

The front tires are gonna get broken in real good now! ;)
 

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Discussion Starter #5 (Edited)
Seems like an exceptionally high utilization. Could be the estimate is off?

Have fun!
Well, we know GM has used the Spark EV as a guinea pig for the gen 2 Volt and upcoming Bolt, so I'm not surprised if they are pushing the limits of the battery pack with an extremely high DoD, to see how well it performs over time. There's only a few thousand Spark EVs out there, so not a huge warranty expense risk.

Other observations:

- at 10% SOC remaining, a message prompts asking if you want to turn off the radio to conserve power (does it really use that much?)
- at 6% SOC, it enters propulsion power reduced aka turtle mode
- at ~2% SOC, it prompts a "CHARGE VEHICLE NOW!" message, and the range estimate switches to just "Low"

Also, compared to the Volt, the Spark's regen in L seems a bit stronger.
 

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Discussion Starter #6
Also, I plugged it into a Chargepoint station around 10:55PM last night, and got the Onstar "completed charging" message at 5:17AM....so around 6 1/2 hours for a full charge. Unfortunately that CP station isn't networked for some reason, so I don't have the kWh details.
 

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Well, we know GM has used the Spark EV as a guinea pig for the gen 2 Volt and upcoming Bolt, so I'm not surprised if they are pushing the limits of the battery pack with an extremely high DoD, to see how well it performs over time. There's only a few thousand Spark EVs out there, so not a huge warranty expense risk.

Other observations:

- at 10% SOC remaining, a message prompts asking if you want to turn off the radio to conserve power (does it really use that much?)
- at 6% SOC, it enters propulsion power reduced aka turtle mode
- at ~2% SOC, it prompts a "CHARGE VEHICLE NOW!" message, and the range estimate switches to just "Low"

Also, compared to the Volt, the Spark's regen in L seems a bit stronger.
If you read the SAE technical paper GM engineers presented on the Bolt propulsion system at April's SAE World Congress, you'll see that going reduced propulsion "turtle" mode is part of the Bolt's battery cycle to get it over 200 miles. The paper provides direct comparisons between the Spark EV propulsion system and the Bolt's in several different areas. Knowledge from the Spark's propulsion system was a huge factor in the Bolt's design.

SAE paper on Bolt propulsion system
 

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I believe GM is not providing the true details on the current Spark EV battery pack provided by LG Chem. In some references they state that battery pack has 19 kWh, in others, 18.4 kWh. They also refuse to state whether this is total capacity or usable.

This one states 18.4 kWh.

http://media.chevrolet.com/media/us/en/chevrolet/vehicles/spark-ev/2015.tab1.html

This one states 19 kWh.

http://gm-volt.com/2014/05/15/2015-spark-ev-gets-lighter-battery-now-built-in-brownstown-performance-stays-the-same/

See this site for the Spark EV.

http://www.chevrolet.com/spark-ev-electric-vehicle/specs/trims.html

Look under mechanical specs, find Lithium-Ion battery propulsion, and click on "i" for info.

The battery pack provides 82 miles of range, has an EPA rating of 119 MPGe, and uses 28 kWh per 100 miles.

So let's examine these numbers.

If 119 MPGe is divided by 33.7 kWh (equivalent energy in a gallon of gasoline per the EPA), we get 3.53 miles per kWh (this number includes charging losses). For the total system, charging efficiency is ~ 84%. Therefore, energy in the battery provides 4.2 miles per kWh. For an 82 mile range, this equates to 19.5 kWh usable!

I don't think GM is using 95% or more of the battery capacity, but are just understating what they really have in the pack.

About a year ago, maybe a little more, GM had an online session where we could ask questions about the Gen 2 Volt. I wrote in and asked why the Spark with its 18.4 kWh battery pack and the new Volt with its 18.4 kWh battery pack has such large variations in range? They also shared a lot to the same hardware.

My rationale was that at 106 MPGe for the new Volt vs. 119 MPGe for the Spark should only mean a difference in range of 9 miles (73 miles vs. 82). It took a while to get a response, but the answer came back that the Spark and Volt did not use the same battery cells.

My conclusion; the Spark uses more energy dense cells than the Gen 2 Volt and GM is not providing the true capacity of the Spark's pack in its specs.
 

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Discussion Starter #9
I believe GM is not providing the true details on the current Spark EV battery pack provided by LG Chem. In some references they state that battery pack has 19 kWh, in others, 18.4 kWh. They also refuse to state whether this is total capacity or usable.

This one states 18.4 kWh.

http://media.chevrolet.com/media/us/en/chevrolet/vehicles/spark-ev/2015.tab1.html

This one states 19 kWh.

http://gm-volt.com/2014/05/15/2015-spark-ev-gets-lighter-battery-now-built-in-brownstown-performance-stays-the-same/

See this site for the Spark EV.

http://www.chevrolet.com/spark-ev-electric-vehicle/specs/trims.html

Look under mechanical specs, find Lithium-Ion battery propulsion, and click on "i" for info.

The battery pack provides 82 miles of range, has an EPA rating of 119 MPGe, and uses 28 kWh per 100 miles.

So let's examine these numbers.

If 119 MPGe is divided by 33.7 kWh (equivalent energy in a gallon of gasoline per the EPA), we get 3.53 miles per kWh (this number includes charging losses). For the total system, charging efficiency is ~ 84%. Therefore, energy in the battery provides 4.2 miles per kWh. For an 82 mile range, this equates to 19.5 kWh usable!

I don't think GM is using 95% or more of the battery capacity, but are just understating what they really have in the pack.

About a year ago, maybe a little more, GM had an online session where we could ask questions about the Gen 2 Volt. I wrote in and asked why the Spark with its 18.4 kWh battery pack and the new Volt with its 18.4 kWh battery pack has such large variations in range? They also shared a lot to the same hardware.

My rationale was that at 106 MPGe for the new Volt vs. 119 MPGe for the Spark should only mean a difference in range of 9 miles (73 miles vs. 82). It took a while to get a response, but the answer came back that the Spark and Volt did not use the same battery cells.

My conclusion; the Spark uses more energy dense cells than the Gen 2 Volt and GM is not providing the true capacity of the Spark's pack in its specs.
In GM documentation to dealers in MD, it stated the Spark EV was eligible for $2,300 in MD state tax credits. MD awards $125 per kWh, so to get $2,300, the battery capacity would need to be 18.4 kWh. So officially, the Spark EV's battery is 18.4 kWh.

Whether GM is understating the official capacity (which would reduce tax credits in MD), or whether over 95% of the battery is really being used is the question. I'm leaning towards the latter, since understating the capacity doesn't benefit GM in any way.
 

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Very interesting info.
Thank you, bro1999, hvacman & BillR!
 

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In the SAE paper that I linked to in my earlier post, Table 3 compares the Spark EV's battery with the Bolt's. GM's engineers say the Spark EV has a "20 kWhr" nominal energy, with 82 miles EPA range and the Bolt has 60 kWhr with >200 miles (Estimated). This isn't sales data. This is in-house engineering data, so it probably is more correct than various nominal specs released by marketing.
 

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I've got a '14 Spark EV which I believe has an A123 battery, not an LG supplied one. Not sure what the difference is between the two in composition and weight, but I'm continually getting mid 90's range estimate upon charging to full. Once even got 100 miles estimated range, even took a picture of the dash panel readout, but too lazy on this day to figure out how to show it here.

I believe I could hypermile it up to a 110-120 mile range. Now that the weather has warmed up, I'll be looking forward to giving it a shot. Just for fun.

BTW..... range anxiety vs. gas anxiety - having owned a Volt for 3 years and now the Spark EV, my realization of which is better or worse between the two is....... gas anxiety is worse, at least for me. The Volt always has the capability of going beyond its EV range, and it was a constant daily battle to drive without using gasoline. I was always checking the lifetime MPG number and my primary objective was to keep it from falling. With the Spark, I've learned what its radius from my home is in terms of my own comfort, and so what I've figured out is a done deal. No gasoline is involved - its either do or die. And as I don't want to die, I make sure I have enough of what I need to get home. Or I use my other, ICE powered vehicle if death looms. Nice rationalization that the Spark is causing less gas miles out of that other vehicle.
 

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Discussion Starter #13 (Edited)
So being able to make my 17 mile R/T commute, A/C blasting, without a care for range is pretty sweet. With the C-Max Energi, I always had to be careful, but not with the Spark EV!

I'll give you 1 guess as to when my range test ended and the 'pedal to the metal' driving started. :p

 

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.....I'll give you 1 guess as to when my range test ended and the 'pedal to the metal' driving started. :p
I think I see when the FUN began!

Go for it! Electrons are cheap. Where I live they are free (for a while) and there are 14 DCFC stations around the metro area, so I can have days +150 miles, if I'm out running errands all over town.

Today I'm leaving work and heading way out into the country, then back to the closest DCFC, 71 miles total.
Then after buying an orange juice in the Starbucks, (just to be nice while I suck it up at the DCFC), I then head 25 miles home.
No anxiety for me. But I'll probably use an old 2 lane highway in one direction instead of the 75 MPH interstate...

Use up those wimpy 185 LRR front tires. You can replace them with Performance 195's all around. Lots of owners have gone that route. Why 'pinch those electrons' if you have more range than you need? FUN is a factor!
 

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Discussion Starter #15
I think I see when the FUN began!

Go for it! Electrons are cheap. Where I live they are free (for a while) and there are 14 DCFC stations around the metro area, so I can have days +150 miles, if I'm out running errands all over town.

Today I'm leaving work and heading way out into the country, then back to the closest DCFC, 71 miles total.
Then after buying an orange juice in the Starbucks, (just to be nice while I suck it up at the DCFC), I then head 25 miles home.
No anxiety for me. But I'll probably use an old 2 lane highway in one direction instead of the 75 MPH interstate...

Use up those wimpy 185 LRR front tires. You can replace them with Performance 195's all around. Lots of owners have gone that route. Why 'pinch those electrons' if you have more range than you need? FUN is a factor!
Still looking out for my first (decent) stoplight victim for my Spark. No pride in smoking a soccermom in a minivan. :p

btw, what do you do for tire rotations, since the rears and fronts can't be swapped?? Do they just rotate left to right? If so, I'm not paying for that.
 

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I haven't rotated my tires yet (only about 3,000 miles-didn't drive it much in the winter). Not sure if left to right really will do much.

I was surprised to see your battery conditioning at 1% for your test. I believe most people have never seen this, unless really cold, or perhaps you had the sun beating down on the car for a while when parked. With decent weather (70 deg) and hypermiling, I've been able to get between 100-110. Of course that goes down if you are first at a light and want to challenge the driver next to you. LOL. I like to take off to show the incredible acceleration.
 

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...btw, what do you do for tire rotations, since the rears and fronts can't be swapped?? Do they just rotate left to right? If so, I'm not paying for that.
Correct, only left to right 'rotations'.
I have +15k on a set of "Ultra High Performance A/S" Kumho tires and I haven't rotated them left to right yet.
I might not at all... The left front is worn just a little more than the right front, as to be expected.
Some say don't do it if not needed. These are directional in that they have an 'Outside' but are not Unidirectional.
I took off the stock LRR tires at 3500 miles and I'm saving them for,?, later, I guess...

I could rotate them myself, but then I'd still have to buy a dozen donuts to get the 'TPMS relearn' performed at my favorite dealership.

They're '420 AA A' rated tires and I'm surprised with the wear rate so far. It's better than I was hoping for.
Plus I went with the stock sizing of 185 F / 195 R. This was before I read about other owners using 195 on all four.
I flog it quite a bit, but usually just go with the flow when commuting.
 

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Discussion Starter #18
What about psi? I noticed my Spark came home from the dealership inflated to 40/41 psi all around.
 

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What about psi? ...
IMHO,, It's your call.

I have run them at the tire's rated Max of 51 psi and the car's spec of 38 psi and everywhere in between.
I know it's getting the best kWh/mi at max but it's a little 'dancy' over small ripples and bumps and such, which tends to wake up the 'Stab Control' sooner. (,,, nanny state, Thanks Obama, etc, etc, only,, it can save your bacon when you do goofy things on slick roads. This I know!)

I'm mostly in the low to mid 40's, you?

Heck, they change ± 5 psi if one side is sitting in the sun. They rise in pressure as soon as you start driving.
Some people talk about 5 psi differences like they can really feel it....
 

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Discussion Starter #20
IMHO,, It's your call.

I have run them at the tire's rated Max of 51 psi and the car's spec of 38 psi and everywhere in between.
I know it's getting the best kWh/mi at max but it's a little 'dancy' over small ripples and bumps and such, which tends to wake up the 'Stab Control' sooner. (,,, nanny state, Thanks Obama, etc, etc, only,, it can save your bacon when you do goofy things on slick roads. This I know!)

I'm mostly in the low to mid 40's, you?

Heck, they change ± 5 psi if one side is sitting in the sun. They rise in pressure as soon as you start driving.
Some people talk about 5 psi differences like they can really feel it....
My psi seems to have settled right at 40....I think I'll just keep it there.

Though I think I *could* make an entire week's worth of commuting on just a single charge if I hypermiled....but nope, spent 2 years nursing the C-Max on my commute every day doing that. Sport mode + L and copious A/C use it is!! :D

Still searching for my first stoplight victim...
 
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