MrDRMorgan
Posts: 931
Joined: Wed Oct 30, 2013 7:27 am
Location: Manteca, California

Re: Battery degredation

Wed Apr 10, 2019 11:37 am

Kermit wrote:
Wed Apr 10, 2019 10:42 am
I purchased mine from Carvana off of a lease as well. It was a 2016 and originally showed 16.2667 with Torque pro. It is now at 16.0667 with ~13,000 miles on it just for reference. I drive very conservatively (averaging 6-7kWh per mile) and after a month of driving the range went from a full charge of 70 up to 98 miles at full.

I have not done enough testing to find out but I believe the kWh reading in Torque pro only changes after you fully charge the car and turn it back on. I can not confirm if the degradation happens all the time and it just calculates it for Torque pro to see at 100% or if charging to 100% lowers it I would assume it's the former. I will charge again in a month to see and may skip a month of charging to 100% to see if i'm correct.
You will get correct readings if the car is powered on. Full-charge TorquePro data I have taken for the last 9 months on both my 2014 and 2016 Spark EVs shows an annual degradation rate of 1.2 kWh per year. I just began a new series of tests where I will only charge the car to 80 - 85% SoC. I want to see if not fully charging the HV battery will slow down or stop the degradation.

RSC
Posts: 27
Joined: Thu Sep 20, 2018 5:45 am

Re: Battery degredation

Wed Apr 10, 2019 4:12 pm

MrDRMorgan wrote:
Wed Apr 10, 2019 11:37 am
I just began a new series of tests where I will only charge the car to 80 - 85% SoC. I want to see if not fully charging the HV battery will slow down or stop the degradation.
Currently I'm using rate and departure time charging. I don't have any experience with departure time charging, but I'm thinking about trying your approach. Let's say you set departure time to 10am, and disconnect at 8am before charging is complete. Then if you reconnect at 11am, will the car immediately resume charging, or will it delay charging, thinking that departure time is 10am tomorrow?

I'm a little reluctant to the leave the car disconnected in the heat of the day. Living in Sonora, it gets pretty hot in my garage in the summer. I got the car in September, so it hasn't yet been through hot weather. So far I've insulated a southwest facing wall that gets pretty hot in the afternoon and the northwest facing garage door that gets some late afternoon sun. I'll probably add reflective bubble wrap type insulation on the rafters and/or a gable vent.
Ray
2015 Spark EV 1LT, DCFC

MrDRMorgan
Posts: 931
Joined: Wed Oct 30, 2013 7:27 am
Location: Manteca, California

Re: Battery degredation

Wed Apr 10, 2019 6:44 pm

RSC wrote:
Wed Apr 10, 2019 4:12 pm
MrDRMorgan wrote:
Wed Apr 10, 2019 11:37 am
I just began a new series of tests where I will only charge the car to 80 - 85% SoC. I want to see if not fully charging the HV battery will slow down or stop the degradation.
Currently I'm using rate and departure time charging. I don't have any experience with departure time charging, but I'm thinking about trying your approach. Let's say you set departure time to 10am, and disconnect at 8am before charging is complete. Then if you reconnect at 11am, will the car immediately resume charging, or will it delay charging, thinking that departure time is 10am tomorrow.

I'm a little reluctant to the leave the car disconnected in the heat of the day. Living in Sonora, it gets pretty hot in my garage in the summer. I got the car in September, so it hasn't yet been through hot weather. So far I've insulated a southwest facing wall that gets pretty hot in the afternoon and the northwest facing garage door that gets some late afternoon sun. I'll probably add reflective bubble wrap type insulation on the rafters and/or a gable vent.
If you have your car set for a departure time of 11:00 am, disconnect before 11:00 am and then reconnect before 11:00 am, I think the car will charge until 11:00 am and then shut off. If you go past 11:00 am, a new charging cycle will start and charging will not start until the time is reached to start charging so it will be fully charged at 11:00 am the next day. I have never tried this.

I have both of my Spark EVs set for departure time charging and both cars are disconnected at 8:00 am each morning. My 2014 departure time is set to 11:30 am. Unfortunately, Each day, I have to manually reset the charging rate to 12 amps as I am using my L1 EVSE which delivers 1.4 kWh to the car at 12 amps. I also plan to test the default 8 amp charging rate so I do not have to reset the charging rate each day. My 2016 departure time is set to 9:15 am as I am using my L2 EVSE which delivers 3.3 kWh power to the car. My target for both cars is to have an SoC of 80 to 85% when I disconnect at 8:00 am. The 2016 is dialed in but the SoC in my 2014 is a bit high. I am seeing about 88% SoC at disconnect time so I moved my departure time from 11:00 am to 11:30 am. I will see if that works when I check the SoC tomorrow morning.

One thing to keep in mind is how long it takes to recharge your car at different charging rates. 8 amps will give you about 0.75 kWh per hour into the battery. 12 amps will give you about 1.0 amp per hour into the battery. If the capacity of your battery is 16 kWh and you need to add 60% to get to 80% you will need to add about 10 kWh. That equates to about 13.3 hours at an 8 amp charge rate and 10 hours at a 10 amp charge rate. My L2 EVSE will add about 2.8 kWh per hour into the battery. This equates to about 3.57 hours of charging.

I live in Manteca which is about 90 miles West of Sonora so I see some of the same summer heat. My garage easily hits temperatures over 100 deg. F during really hot summer days. If you have access to TorquePro, you can measure the battery temperature to see how hot it gets during the hot summer months. I do not know if battery cooling is active if your car is set to departure time. If it is, I would keep the car plugged in. I also do not know if the L1 EVSE can supply enough power to run the battery cooling circuit.

RSC
Posts: 27
Joined: Thu Sep 20, 2018 5:45 am

Re: Battery degredation

Thu Apr 11, 2019 6:26 am

Thank you. I'll probably do some experimenting. I don't have TorquePro, but I've been thinking about it and an ODB2 adapter. I hope that you will tell us what you observe with your change in routine.

I get where some people are coming from on trying to manage the state of charge. I'm not going to be continually monitoring the charge level or running out to the garage at 3 in the morning to disconnect. One of the main reasons I got the car was to simplify my life (no gas stations, oil changes, or frequent maintenance), not to add complexity.

However, one of the factors in my situation is that I live on a hill, in East Sonora, with a 1000 foot descent into Sonora proper. I wish the Spark EV had Hilltop Reserve like the Bolt, so that I could get full advantage of regen. If I can somehow emulate Hilltop Reserve easily in a semi-automated manner, I'll do that.
Ray
2015 Spark EV 1LT, DCFC

MrDRMorgan
Posts: 931
Joined: Wed Oct 30, 2013 7:27 am
Location: Manteca, California

Re: Battery degredation

Thu Apr 11, 2019 7:59 am

RSC wrote:
Thu Apr 11, 2019 6:26 am
Thank you. I'll probably do some experimenting. I don't have TorquePro, but I've been thinking about it and an ODB2 adapter. I hope that you will tell us what you observe with your change in routine.

I get where some people are coming from on trying to manage the state of charge. I'm not going to be continually monitoring the charge level or running out to the garage at 3 in the morning to disconnect. One of the main reasons I got the car was to simplify my life (no gas stations, oil changes, or frequent maintenance), not to add complexity.

However, one of the factors in my situation is that I live on a hill, in East Sonora, with a 1000 foot descent into Sonora proper. I wish the Spark EV had Hilltop Reserve like the Bolt, so that I could get full advantage of regen. If I can somehow emulate Hilltop Reserve easily in a semi-automated manner, I'll do that.
I wouldn't get up at 3 am either! Try using the 8 amp charging rate to see how long it takes to get your car charged to a desired level like 80%. As I pointed out, the 8 amp charging rate only puts about 0.75 kWh per hour back into the battery. This amounts to about 9 kWh in 12 hours.

If you charge your Spark to about 60% and drive down the hill to Sonora with the selector set to L, you should be able to use the Blue GOM ball to estimate how much regen adds back into your battery and then charge your battery accordingly the next time you go down to Sonora.

Plugshare shows 10 ChargePoint CCS EVSE stations at Adventist Health in Sonora and they are FREE! BUT.... remember that the Spark EV will only charge at a maximum 3.3 kWh rate which puts about 2.8 kWh per hour back into the battery. You will have to figure out how many kWhs and hours of charging time it takes so you can get comfortably back from Adventist Heath to your home. Be sure to account for the higher uphill power consumption rate. Hopefully, someone will install a DCFC location(s) in Sonora. Oakdale now has a free ChargePoint 6.6 kWh station at the library and 2 ChargePoint DCFC stations are now under construction on Third Street. Perhaps Jamestown and Sonora will follow. I would love to try a trip to Pinecrest but right now it is not possible.

On a trip my wife and I made to South Lake Tahoe, we charged in the parking garage in Heavenly and then headed back home. The climb up to Echo Summit from South Lake Tahoe gobbled quite a few kWhs but we made it. Then, with the car in L, we made it all the way down the hill to Folsom where we needed to charge in order to get home. For us, that downhill adventure was an "E" ticket ride all the way down and I enjoyed every minute of it!

Kermit
Posts: 37
Joined: Mon Feb 04, 2019 10:47 am

Re: Battery degredation

Thu Apr 11, 2019 9:47 am

MrDRMorgan wrote:
Wed Apr 10, 2019 11:37 am
Kermit wrote:
Wed Apr 10, 2019 10:42 am
I purchased mine from Carvana off of a lease as well. It was a 2016 and originally showed 16.2667 with Torque pro. It is now at 16.0667 with ~13,000 miles on it just for reference. I drive very conservatively (averaging 6-7kWh per mile) and after a month of driving the range went from a full charge of 70 up to 98 miles at full.

I have not done enough testing to find out but I believe the kWh reading in Torque pro only changes after you fully charge the car and turn it back on. I can not confirm if the degradation happens all the time and it just calculates it for Torque pro to see at 100% or if charging to 100% lowers it I would assume it's the former. I will charge again in a month to see and may skip a month of charging to 100% to see if i'm correct.
You will get correct readings if the car is powered on. Full-charge TorquePro data I have taken for the last 9 months on both my 2014 and 2016 Spark EVs shows an annual degradation rate of 1.2 kWh per year. I just began a new series of tests where I will only charge the car to 80 - 85% SoC. I want to see if not fully charging the HV battery will slow down or stop the degradation.
I appreciate all the detail you are providing in your posts. This is the information I am also trying to track and log in our climate (West TN).

I have been keeping the charge below 100% to see if it increases the battery lifespan. I've never seen the kWh change except after a full charge to 100% have you? I can try this when I get home tonight. I wonder if it only chagnes at a 100% charge if this confirms that battery cell balancing only occurs at 100% charges.

As far as convenience in charging I typically plug my car in when I get home and flip the breaker before I go to sleep which keeps it in the 60-80% range. Since it is on it's own breaker and our panel is inside the house I just flip the breaker so I don't have to go outside. I keep the android phone inside the house and I check the charge with it so I can manage it from inside the house. If it still needs more charge then I turn the breaker back on in the morning when I wake up.

The information you provided on the departure time and charge rates is very useful. I think I will experiment with that to make charging a bit more automatic. We don't have a garage so our car is out in the heat all the time so confirming if the cooling is on when it's plugged in but not charging would be good to know.
2016 Spark EV

RSC
Posts: 27
Joined: Thu Sep 20, 2018 5:45 am

Re: Battery degredation

Sat Apr 13, 2019 7:02 am

MrDRMorgan wrote:
Thu Apr 11, 2019 7:59 am
I would love to try a trip to Pinecrest but right now it is not possible.
You could maybe do it, but I'm sure that it would be anxiety-inducing. I've been to Pinecrest and back from my home. I should have written it down, but as I recall, I had about 25 miles on the guessometer when I got there, and 35 miles when I got back. This is with myself, one passenger, and a light foot on the accelerator.

There are the chargers at Adventist Health, and if you can't quite make it that far, you might be able to charge at the Chevy dealer in Jamestown (Sierra Motors). I haven't tried the Chevy dealer. Supposedly according to PlugShare there is someone in Chinese Camp.

For me, going down to Sonora and back on a partial charge is not a problem. I've done as many as three round trips without getting uncomfortably low.
Kermit wrote:
Thu Apr 11, 2019 9:47 am
We don't have a garage so our car is out in the heat all the time so confirming if the cooling is on when it's plugged in but not charging would be good to know.
If I determine whether cooling is on when plugged in but not charging, I'll report back, but it probably can't be until sometime in late July.
Ray
2015 Spark EV 1LT, DCFC

MrDRMorgan
Posts: 931
Joined: Wed Oct 30, 2013 7:27 am
Location: Manteca, California

Re: Battery degredation

Sat Apr 13, 2019 7:41 am

RSC wrote:
Sat Apr 13, 2019 7:02 am
MrDRMorgan wrote:
Thu Apr 11, 2019 7:59 am
I would love to try a trip to Pinecrest but right now it is not possible.
You could maybe do it, but I'm sure that it would be anxiety-inducing. I've been to Pinecrest and back from my home. I should have written it down, but as I recall, I had about 25 miles on the guessometer when I got there, and 35 miles when I got back. This is with myself, one passenger, and a light foot on the accelerator.

There are the chargers at Adventist Health, and if you can't quite make it that far, you might be able to charge at the Chevy dealer in Jamestown (Sierra Motors). I haven't tried the Chevy dealer. Supposedly according to PlugShare there is someone in Chinese Camp.

For me, going down to Sonora and back on a partial charge is not a problem. I've done as many as three round trips without getting uncomfortably low.
Kermit wrote:
Thu Apr 11, 2019 9:47 am
We don't have a garage so our car is out in the heat all the time so confirming if the cooling is on when it's plugged in but not charging would be good to know.
If I determine whether cooling is on when plugged in but not charging, I'll report back, but it probably can't be until sometime in late July.
TorquePro can be used to measure the battery temperature to see if battery cooling is in operation.

MrDRMorgan
Posts: 931
Joined: Wed Oct 30, 2013 7:27 am
Location: Manteca, California

Re: Battery degredation

Sat Apr 13, 2019 7:59 am

RSC wrote:
Sat Apr 13, 2019 7:02 am
MrDRMorgan wrote:
Thu Apr 11, 2019 7:59 am
I would love to try a trip to Pinecrest but right now it is not possible.
You could maybe do it, but I'm sure that it would be anxiety-inducing. I've been to Pinecrest and back from my home. I should have written it down, but as I recall, I had about 25 miles on the guessometer when I got there, and 35 miles when I got back. This is with myself, one passenger, and a light foot on the accelerator.

There are the chargers at Adventist Health, and if you can't quite make it that far, you might be able to charge at the Chevy dealer in Jamestown (Sierra Motors). I haven't tried the Chevy dealer. Supposedly according to PlugShare there is someone in Chinese Camp.

For me, going down to Sonora and back on a partial charge is not a problem. I've done as many as three round trips without getting uncomfortably low.
Kermit wrote:
Thu Apr 11, 2019 9:47 am
We don't have a garage so our car is out in the heat all the time so confirming if the cooling is on when it's plugged in but not charging would be good to know.
If I determine whether cooling is on when plugged in but not charging, I'll report back, but it probably can't be until sometime in late July.
The 35 miles from Oakdale to Sonora will be easy to do once the DCFC station in Oakdale is in operation. Then, I would need a full charge in Sonora to attempt getting to Pinecrest. However, I really do not like waiting hours for my car to charge at L2 stations even though I am glad they are available. But... who knows. I might get the bug to try it!

RSC
Posts: 27
Joined: Thu Sep 20, 2018 5:45 am

Re: Battery degredation

Sat Apr 13, 2019 10:49 am

MrDRMorgan wrote:
Sat Apr 13, 2019 7:41 am
TorquePro can be used to measure the battery temperature to see if battery cooling is in operation.
I think I'll do that. An OBD2 adapter came in the mail yesterday, but I haven't yet set up Torque Pro or even really looked into it.
Ray
2015 Spark EV 1LT, DCFC

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