Battery degredation

[kevin]

I have a 2014 spark with about 31k miles on it now. I have had it for 2 years. I have had no loss of capacity. I do nothing to baby the battery. I just drive it and plug it in every day to charge up to 100%. Just one of the reasons I call it Super Spark.

That's very good, although surprising given my experience.

What is the estimated capacity? How are you estimating it?

This is my 2014 Spark EV:

Kevin

 

[CSW]

welp, my claims are not as scientific.....haha! All I am going by is the car still goes just as far as it always has. Thanks it. Only drop I have even seen is when it gets kinda cold, like in the 30s to 40s degree range. Otherwise the car has been great. I plan on buying it when the lease is over if the price is right.

 

[zzcoopej]

What is the estimated capacity? How are you estimating it?

This is my 2014 Spark EV:

Kevin

That's a great graph Kevin, thanks for posting.
We are close to getting our automatic battery degradation graphing App to work with the Spark EV, hopefully we will be in a position to release by the end of May. As users feed their data into our cloud database we can compare 1 owner to all owners, and will even be able to compare battery chemistry and brands to each other. Here is the graph we got with another EV battery - http://www.evpositive.com/battery-history.html

 

[MrDRMorgan]

I have a 2014 spark with about 31k miles on it now. I have had it for 2 years. I have had no loss of capacity. I do nothing to baby the battery. I just drive it and plug it in every day to charge up to 100%. Just one of the reasons I call it Super Spark.

That's very good, although surprising given my experience.

What is the estimated capacity? How are you estimating it?

This is my 2014 Spark EV:

Kevin

I too have a 2014 Spark EV that I purchased used last August. The car was a Hertz rental and it had only 1500 miles on it. I now have 5200 miles on the odo and my average battery capacity for the last 13 L2 charging sessions is 18.84 kWh. This value fits your graph at 5429 miles. I checked back to some earlier data I took in Sep 2015 and, for 3 charging sessions, my battery capacity was about 20 kWh - again it fits on your graph although a little bit high. I think it would be interesting for 2014 Spark EV drivers to report their findings too so a graph could be created to represent all 2014 Spark EVs. The same should be done for the 2015 Spark EV.

 

[TheLondonBroiler]

According to Torque Pro, my 2015 is down to 15.3kwh capacity. It's at 28,000 miles, lifetime efficiency 5.3mpkwh. I fast charge at least once a week on average, and charge to 100% after having been somewhere (work is 62 miles round trip).

The drop from 15.4 to 15.3 occurred two days after my epic 560 mile trip in one day, which consisted of 9 fast charge sessions ( battery temp never went beyond 91°F).

 

[Zoomit]

My 2015 seems to be down to about 15.4kWh, just backing out capacity from on-board pie chart data. It's at 31,000mi and gets left at 100% SoC frequently. It has less than 10 DCFC sessions in total over it's lifetime.

 

[MrDRMorgan]

According to Torque Pro, my 2015 is down to 15.3kwh capacity. It's at 28,000 miles, lifetime efficiency 5.3mpkwh. I fast charge at least once a week on average, and charge to 100% after having been somewhere (work is 62 miles round trip).

The drop from 15.4 to 15.3 occurred two days after my epic 560 mile trip in one day, which consisted of 9 fast charge sessions ( battery temp never went beyond 91°F).

This is interesting data. Only recently did I start using TorquePro and an OBDLink MX adapter to monitor my 2014 and 2016 Spark EVs. I had to turn in my 2015 Spark EV before TorquePro was working for me. But.... I had about 28K miles on my 2015 Spark EV and, in December 2017, I experienced a significant drop in my calculated battery capacity to between 15.0 and 15.3 kWh. A friend of mine, who also has a 2015 Spark EV, brought his car over the other day and we used TorquePro and my OBDLink MX adapter to measure his battery capacity. It measured 14.8 kWh with 29155 miles on the ODO.

It appears there might be a problem with the HV battery in the 2015 Spark EV.

For reference and as measured by TorquePro using my OBDLink MX adapter, the battery capacity in my 2014 Spark EV measures 17.2 kWh at 14,234 miles and the battery capacity in my 2016 Spark EV measures 16.8 kWh at 10,859 miles.

 

[TheLondonBroiler]

Thank you Zoom & Morgan for your replies and good info.

15% battery capacity loss (assuming the battery had 18kwh usable when new), in 2 years 8 months & 28k miles, is concerning. I did comfort myself by digging up the 2016 Chevrolet warranty guide pdf on the internet (I received no manual or warranty packet when I purchased used), confirming that degradation beyond 40% merits repair/replacement. If the capacity loss continues at its current rate (I understand it very well could slow down), I would end up with a warranty claim.

 

[MrDRMorgan]

Thank you Zoom & Morgan for your replies and good info.

15% battery capacity loss (assuming the battery had 18kwh usable when new), in 2 years 8 months & 28k miles, is concerning. I did comfort myself by digging up the 2016 Chevrolet warranty guide pdf on the internet (I received no manual or warranty packet when I purchased used), confirming that degradation beyond 40% merits repair/replacement. If the capacity loss continues at its current rate (I understand it very well could slow down), I would end up with a warranty claim.

My friend, who introduced me to the 2015 Spark EV in May of 2015, also has a 2015 Spark EV and his lease ends this month. Last week I measured his battery capacity using TorquePro and an OBDLink MX adapter and found his battery capacity was 14.8 kWh. His 2015 Spark EV has just about 30K miles on the ODO.

For reference, the current HV battery capacity for my 2014 Spark EV with 14k miles on the ODO is 17.2 kWh and for my 2016 Spark EV with 11k on the ODO, the HV battery capacity is 16.8 kWh.

The Spark EV HV battery warranty is for 8 years or 100k miles and if the battery degrades more than 40% during the warranty period.

 

[CSW]

How can the 2015 be so much worse? I should be the exact same battery as the 2016 yes? I have a 2015 and a 2016 spark, I am thinking maybe I should give back the 2015 when the lease is up in November and try to find a nice used 2014 spark .... only issue is my wife loves the blue & it would have to be a blue one.... prob very hard to find is my point.

 

[MrDRMorgan]

How can the 2015 be so much worse? I should be the exact same battery as the 2016 yes? I have a 2015 and a 2016 spark, I am thinking maybe I should give back the 2015 when the lease is up in November and try to find a nice used 2014 spark .... only issue is my wife loves the blue & it would have to be a blue one.... prob very hard to find is my point.

My guess is the 2015 Spark EV was the first year for the LG cells and there may have been some start up problems with the cells. The 2014 Spark EV used cells from A123 Systems. I also suspect the 2016 Spark EV, which also uses the LG cells, may have benefited from improvements by LG. My 2014 Spark EV and my 2016 Spark EV both are both giving great HV battery performance. However, I will not know for sure if the 2016 suffers from the same problem as the 2015 until I get to 30k miles on the ODO. Right now the battery capacities for both my 2014 and 2016 Spark EVs are rock solid.

Most of my driving is local and in town. Right now, the GOM on both cars typically show about 100 miles after a full charge.

 

[CSW]

Well then, my plan now is to give back the 2015 and search for a used 2014 or 2016 in blue with quick-charge. I have about 3-4 months to get er dun, should be nuff time I think.

..... but isn't the battery in the 2015 and 2016 spark the same as the Volt battery in terms of chemistry and construction ? I have not heard of any big degredation issues in the Volt?

 

[MrDRMorgan]

Well then, my plan now is to give back the 2015 and search for a used 2014 or 2016 in blue with quick-charge. I have about 3-4 months to get er dun, should be nuff time I think.

..... but isn't the battery in the 2015 and 2016 spark the same as the Volt battery in terms of chemistry and construction ? I have not heard of any big degredation issues in the Volt?

I do not know much about the Volt other than they seem to be quite reliable with little or no HV battery degradation.

What I can tell you about the Spark EV HV battery is this:

2014 Spark EV HV Battery:
Mass: 254 kg
Battery chemistry: lithium ion
Thermal system: liquid active thermal control
Cells: 336
Electric driving range: 82 miles (EPA estimate)
Energy: 21 kWh
Battery Power: 120 kW

2015 Spark EV HV Battery:
Mass: 215 kg
Battery chemistry: lithium ion
Thermal system: liquid active thermal control
Cells: 192
Electric driving range: 82 miles (EPA estimate)
Energy: 18.4 kWh
Battery Power: 120 kW

2016 Spark EV HV Battery:
Mass: 215 kg
Battery chemistry: lithium ion
Thermal system: liquid active thermal control
Cells: 192
Electric driving range: 82 miles (EPA estimate)
Energy: 19 kWh
Battery Power: 120 kW

This all comes from Chevrolet's Product Information for the 2014, 2015 and 2016 Spark EVs.

 

[CSW]

Hm. Interesting. The 2016 has more power avail even tho all the other specs are the same. Well, my plan is still the same then. 2015 going back, prefer a 2014 used.

 

[CCIE]

There wasn’t a change in battery size from 2015 to 2016. I’m not sure where that info came from, but it’s inaccurate. They both use the same battery.

 

[MrDRMorgan]

There wasn’t a change in battery size from 2015 to 2016. I’m not sure where that info came from, but it’s inaccurate. They both use the same battery.

That is correct. The 2015 and 2016 use the same LG battery. It would be interesting to know how many drivers of the 2015 Spark EV have experienced a significant drop in HV battery capacity. Gradual degradation should be expected.

 

[MrDRMorgan]

I've had my 2014 Spark for now a year and 8 months. The car now has 23k on the odometer but my battery life has suffered greatly. I began with 80-100 miles of range (depending on my driving style and weather), but now I'm getting 60-75 miles.

I've used the built in battery usage meter, and today, I had 8.8 KW used at 50% battery life. This indicates I have somewhere around 17.6 KW total battery life. That is a nearly 16% battery life lost. Does anyone else have this type of battery deterioration? Anyone know what Chevy's battery life warranty is, or when they will do something about excessive battery life loss? If I hit the 20% mark, I won't be able to make my daily round trip.

I would consider 17.6 kWh at almost 18K miles very good. My HV battery in my 2014 at 14K miles is 17.2 kWh.

Your driving style and environmental conditions will control what mi/kWh value you get. Most of my driving is around town and I drive in L all of the time. It is not very difficult for me to get 100 miles of range after a full charge; regen helps a lot. But, if I have to use the A/C or the heater, my mi/kWh drops considerably. Freeway speeds above about 60 mph have a significant impact on mi/kWh too but nothing beats the heater for killing kWhs.

 

[SparkyJ]

(Taken from pushev article comparing spark and bolt with lg chem cells)The Chevrolet Spark EV battery is made with 192 (2p96s) LG Chem cells, each cell is rated at 27 Ah and 3.75 V. This represents a total of 19.44 kwh (192 x 27 Ah x 3.75 V). The battery volume is 135 L and the mass is 215 kg, this means an energy density of 144 Wh/L and 90 Wh/kg at the battery level, not cell.”

One thing to note, the energy display is not accurate very often. I finally got around to inputting the PID's in torque to read data and it reports 16.1kwh for the battery, I will keep an eye on that as well to see if it is accurate. The energy display can show anywhere from roughly 17.6 kwh to 16.2 kwh on any given day...way off IMO and not to be trusted. Hopefully the reporting from the torque app will be accurate. Also I would suspect the usable kwh from a new 2015 or 2016 spark ev to be around 17.4kwh, about 21k miles on my spark and at 16.1kwh, a bit sad as most of the time from the energy display I was calculating around 17 kwh more often than not. But I guess 16.1 isn't terrible as long as the degradation is slow. If 17.4 is the usable capacity, then losing 1.3 kwh from a battery in a spark sold over 3 years ago really shouldn't be frowned upon.

 

[MrDRMorgan]

(Taken from pushev article comparing spark and bolt with lg chem cells)The Chevrolet Spark EV battery is made with 192 (2p96s) LG Chem cells, each cell is rated at 27 Ah and 3.75 V. This represents a total of 19.44 kwh (192 x 27 Ah x 3.75 V). The battery volume is 135 L and the mass is 215 kg, this means an energy density of 144 Wh/L and 90 Wh/kg at the battery level, not cell.”

One thing to note, the energy display is not accurate very often. I finally got around to inputting the PID's in torque to read data and it reports 16.1kwh for the battery, I will keep an eye on that as well to see if it is accurate. The energy display can show anywhere from roughly 17.6 kwh to 16.2 kwh on any given day...way off IMO and not to be trusted. Hopefully the reporting from the torque app will be accurate. Also I would suspect the usable kwh from a new 2015 or 2016 spark ev to be around 17.4kwh, about 21k miles on my spark and at 16.1kwh, a bit sad as most of the time from the energy display I was calculating around 17 kwh more often than not. But I guess 16.1 isn't terrible as long as the degradation is slow. If 17.4 is the usable capacity, then losing 1.3 kwh from a battery in a spark sold over 3 years ago really shouldn't be frowned upon.

Since June 10, I have used TorquePro and an OBDLink MX adapter to measure the battery capacity in my 2016 Spark EV. It has ranged from 16.6 kWh to the most recent reading of 16.8 kWh. My 2014 Spark EV has been steady at 17.2 kWh over the same period. I also measured the battery capacity for a friend of mine who has a 2015 Spark EV with about 30k Miles on the ODO. His battery read 14.8 kWh.

I have noticed that the energy display [vertical green bar display] seems to transition between bars whenever the battery capacity reaches 81, 71, 61, etc.

 

[SparkyJ]

Hope that works, if not just paste in browser to see page. It is comparing volt lg chem battery with spark a123 battery and shows usable for a123 pack as being 17.3kwh and 81% depth of discharge. Grain of salt needed as I have no idea where that info came from. https://gm-volt.com/wp-content/uploads/2013/08/Slide5.jpg

As a side note, I come across an lg chem website and took a shot at emailing them on the 15-16 spark packs usable capacity. Doubt I will get a reply, but am hoping I do. Curious where the 15-16 DoD sits at as well as the usable capacity since 15-16 are said to be more efficient than the 14 models motor/regen setup. However if usable kwh is similar to the 14's then I have to doubt there's much of a difference with range rating being the same.

Hopefully get an answer to maybe help unravel some of these spec mysteries we have with our little sparks. I know many of our spark ev owners may not care, but things like this are good to know with the ev revolution beginning to take a strong stance in future automotive transportation and learning all we can will certainly drive our future purchase decisions.