Collecting data:Off-the-wall power for turtle to 100% charge

[DaveinOlyWA]

this thread shows that Tick Tock had battery degradation even back then. 21 KW to recharge from the wall? he states 20 going in but that is not likely considering best you might hope for is 88-90%. that would only be 19 going in.

 

[TickTock]

this thread shows that Tick Tock had battery degradation even back then. 21 KW to recharge from the wall? he states 20 going in but that is not likely considering best you might hope for is 88-90%. that would only be 19 going in.

That 20.3% going in was computed by integrating the battery_voltage*battery_current*delta_time. Assuming those messages are accurate, and considering I determined my battrey series resistance to be 70mOhms the number should be accurate. Why do you think the charging efficiency cannot be better then 90%? This isn't that hard to do and given we believe round trip efficiency to be around 85%, this ~92% efficiency seems reasonable to me.

 

[TickTock]

I should also mention that I have triple-checked the at-the-wall measurement EKM-25IDS, DMM+clamp meter, and recently installed a TED system. All three matched within 1.5%.

 

[DaveinOlyWA]

Phil mentioned there is a constant 200-300 watt overhead using on charging system cooling. 200 Watts is 5% do charging efficiency of 95% means power to the pack can't be more than 90%

 

[surfingslovak]

Phil mentioned there is a constant 200-300 watt overhead using on charging system cooling. 200 Watts is 5% do charging efficiency of 95% means power to the pack can't be more than 90%

Yes, there is a cooling pump, and the exact wattage is in an older thread. I keep harping on this, but another thing to consider is battery heat losses during charging. They are unaccounted for, and will lower the overall charging efficiency. As Gary pointed out, we shouldn't forget heat development during discharge either. And then there is cell balancing and related losses Phil brought up earlier. It's fairly certain that the overall efficiency is 85%. We know what flows into the battery, and what gets out of it, and the difference appears to be about 8% on average. This leaves 7% for charger losses.

 

[camasleaf]

OK summarizing so far:

• TickTock:21.7 kWh Dead to 100 from the wall (EKM-25IDS meter, 20.04 kWh actually entering the battery)
  vegastar: 25.5 kWh Turtle to 100 from the wall (72F, 6 temp bars) (22.85kWh recently@275 gids, 393V)
  TomT: 26.8 kWh Turtle to 100 from the wall (TED, new, 26.1 recently)
  surfingslovak: 24.34 kWh from turtle to 100 from the wall using Coulomb EVSE

Anyone else have data to add? Maybe also mention the type of meter used (Blink, Ted, EKM, Kill-a-watt, or ?) since there seems to be some question on the accuracy of some.

Last night my wife came home just above Low Battery. I drove the car around the neighborhood until I got the turtle. From Very Low Battery to turtle was only only 2 miles (with the windows open and the heater to 3-4kW). This is the first turtle in over 13000 miles. The car has rarely seen Low Battery levels and 90% of the time charged to 80%.
Blink showed about 22.3kW this morning (based on cost). It ended at 3:00 am and did not start again, yet.

 

[surfingslovak]

Blink showed about 22.3kW this morning (based on cost). It ended at 3:00 am and did not start again, yet.

Thank you for sharing the data. Was this charge to 80 or 100%? Would you have any idea how cold the battery gets overnight, or at least how many bars the temperature gauge was showing?

 

[camasleaf]

Blink showed about 22.3kW this morning (based on cost). It ended at 3:00 am and did not start again, yet.

Thank you for sharing the data. Was this charge to 80 or 100%? Would you have any idea how cold the battery gets overnight, or at least how many bars the temperature gauge was showing?

I charged to 100% that night. Temperature in the garage is about 50F and the battery usually shows 5 bars in the morning.

 

[GerryAZ]

I will reply with data when I get it compiled. I have been recording trip and charge data on note cards since I picked up my Leaf in June. TickTock's charge kWh numbers from turtle to 100% are significantly lower than I have measured. My commute dictates that I charge to 100% every charge so I may see capacity loss sooner than others.

I finally have my charging data organized. When my Leaf was new it took 22.85 kWh from the wall to charge from shutdown (end of turtle mode) to 100% using L2 with my AV EVSE. On June 30, 2012 at 11,728 miles, it took 21.28 kWh to charge from shutdown to 100%, again using my L2 AV. Therefore, my battery capacity is higher than Tick Tock's, but significantly lower than others have reported. CarWings reported 15.8 and 14.5 kWh, respectively for electricity consumption on the days corresponding to those charging events.

(21.28/22.85)*100=93.13% so I still have 93% of my original capacity after a little over one year in the Arizona desert.

Gerry

 

[vegastar]

These are very interesting results. The question is why are you seeing much less degradation than others Arizona users.

Do you have any special care about the temperature? Do you still charge to 100% every charge? Any chance you could get a gid reading?

 

[TickTock]

I will reply with data when I get it compiled. I have been recording trip and charge data on note cards since I picked up my Leaf in June. TickTock's charge kWh numbers from turtle to 100% are significantly lower than I have measured. My commute dictates that I charge to 100% every charge so I may see capacity loss sooner than others.

I finally have my charging data organized. When my Leaf was new it took 22.85 kWh from the wall to charge from shutdown (end of turtle mode) to 100% using L2 with my AV EVSE. On June 30, 2012 at 11,728 miles, it took 21.28 kWh to charge from shutdown to 100%, again using my L2 AV. Therefore, my battery capacity is higher than Tick Tock's, but significantly lower than others have reported. CarWings reported 15.8 and 14.5 kWh, respectively for electricity consumption on the days corresponding to those charging events.

(21.28/22.85)*100=93.13% so I still have 93% of my original capacity after a little over one year in the Arizona desert.

Gerry

How are you measuring the energy?

 

[RegGuheert]

(21.28/22.85)*100=93.13% so I still have 93% of my original capacity after a little over one year in the Arizona desert.

I would say that result is fully compatible with public statements that Nissan has made about loss of battery capacity in the LEAF. You may not retain 80% of your capacity after 5 years, but you should be in the ballpark.

I wonder if Nissan saw similar results in their testing of LEAFs at their nearby proving grounds.

 

[EdmondLeaf]

These are very interesting results. The question is why are you seeing much less degradation than others Arizona users.

Do you have any special care about the temperature? Do you still charge to 100% every charge? Any chance you could get a gid reading?

Using your and others data in this topic I calculated that GerryAZ have about 230GID @100%

 

[DaveinOlyWA]

At a glance I have to say that Carwings seems to be no more accurate than the last time I checked and now I cannot access worldrankings

 

[DaveEV]

At a glance I have to say that Carwings seems to be no more accurate than the last time I checked and now I cannot access worldrankings

Do you have the NTB11-041a update on your car? Since getting mine updated the data seems to very closely match what the gauges in the car read.

 

[DaveinOlyWA]

I did take it in for the "beep" update. How would I check my version?

At a glance I have to say that Carwings seems to be no more accurate than the last time I checked and now I cannot access worldrankings

Do you have the NTB11-041a update on your car? Since getting mine updated the data seems to very closely match what the gauges in the car read.

 

[TickTock]

(21.28/22.85)*100=93.13% so I still have 93% of my original capacity after a little over one year in the Arizona desert.

I would say that result is fully compatible with public statements that Nissan has made about loss of battery capacity in the LEAF. You may not retain 80% of your capacity after 5 years, but you should be in the ballpark.

I wonder if Nissan saw similar results in their testing of LEAFs at their nearby proving grounds.

Only problem is it appears his original capacity was already down ~7%.

 

[EdmondLeaf]

Only problem is it appears his original capacity was already down ~7%.

I think you agree GerryAZ GID is about 230

 

[DaveEV]

I did take it in for the "beep" update. How would I check my version?

Newest Component Release Levels (firmware,version,software)
If your Boot Ware/Application isn't 147 or higher, you don't have the AV Control Unit portion of the NTB11-041a update which corrects the CARWINGs data. This isn't done as part of the "beep" update that was addressed earlier this year.

In addition to the "no telematics connection" issue, the AV Control Unit update part of NTB11-014a also fixes these issues:

• Navigation system locks up or reboots
• Energy economy on Owner’s Portal website and vehicle do not match
• iPod/iPhone connectivity issues through USB

 

[vegastar]

Only problem is it appears his original capacity was already down ~7%.

I think you agree GerryAZ GID is about 230

I think it should be a little higher. The charging efficiency for L2@16A is around 91.5%, so 21.28*0.915/0.08 = 243 gids.