A 2012 Nissan LEAF Is Now Owned By Someone You May Know

[Right Lane Cruiser]

Hi, Jud! Yes, the Insight is staying.

[MN Driver]

Originally Posted by Right Lane Cruiser

(Since I can't find my Kilowatt meter I'll have to buy another to find out what sort of charging losses I'm looking at.)

I need to pay more attention to what's going on at this site. Do you want to borrow my Kill-a-watt EZ for a few weeks?

[Right Lane Cruiser]

If you can let go of it, absolutely! I've just been assuming 77.5% efficiency based on a post I saw over at mynissanleaf.com

[MN Driver]

Originally Posted by Right Lane Cruiser

If you can let go of it, absolutely! I've just been assuming 77.5% efficiency based on a post I saw over at mynissanleaf.com

Yes, I'm more than willing to let someone else use it for a little while in the interest of science. I'm curious about the 120v charging efficiency too. I'm thinking we can arrange something if you pass through my area again on Monday evening, or whatever works for you.

Not sure how you'll measure the efficiency of the J1772 240v system though, at least it won't be through a Kill-a-watt since they are 120v devices that burn up if you crank the amperage.

[herm]

some of those kill-a-watt devices burn up when used to measure a Leaf charging for hours.. apparently some models are better built.

[herm]

These numbers for charging efficiency look believable :

http://www.mynissanleaf.com/viewtopi...1db9e23faf03de

73% at 120 volts
84% at 240 volts
90%+ on DC

[herm]

Charging losses from the Leaf forum:

120v 77.5%
240v 90.9%

http://www.mynissanleaf.com/viewtopic.php?f=31&t=8583

"Here are my charging measurements on the Leaf:

Charging using the original 120v EVSE: (112.5v recorded at EVSE input)

Standby Power: 4.9w
Charge Power in: 1.451kW
Power to Leaf Battery: 1.125kW
Total Power Lost: 326w
Total Charge Efficiency: 77.5%

These measurements are all using our Rev2 Upgraded EVSE:

120v: (112.6v recorded at EVSE input)
Standby Power: 1.7w
Charge Power in: 1.436kW
Power to Leaf Battery: 1.125kW
Total Power Lost: 311w
Total Charge Efficiency: 78.3%

240v: (239.8v recorded at EVSE input)
Standby Power: 3.4w
Charge Power in: 3.756kW
Power to Leaf Battery: 3.414kW
Total Power Lost: 342w
Total Charge Efficiency: 90.9%

All these measurements were with the Leaf pack at around 62 degrees F and ~65% SoC. Readings were allowed to stabilize before recording. The power to the Leaf battery was calculated by recording amperage at the cell interconnect level using a high-accuracy kelvin-connected current shunt, so the losses are a sum of all EVSE/Charger/Leaf systems. Charger input power was similarly recorded using lab-grade calibrated true RMS equipment, not a Kill-A-Watt.

These efficiency calculations do not take into account the coulombic loss in the Leaf's battery, and other Leaf systems during discharge, so this is only charging efficiency up to the battery pack itself but not including the pack, of which also has notable loss.

While I'm at it, someone asked me recently what the idle draw of the Leaf is. It bounces around a lot, but it's as low as 140w, typically around 160w with all accessories, lights, and CC off, and 230 watts for headlights and 360w with High-Beams on. (My Leaf will be slightly lower, as I've changed most of the incandescent bulbs to LED.) Again, these power measurements were derived by recording amperage at the cell interconnect level using a high-accuracy kelvin-connected current shunt.

If anyone wants to know any highly accurate information about the Leaf's systems, I might have already recorded it, feel free to ask!

-Phil"

[Right Lane Cruiser]

My Kill-A-Watt measurements averaged at 71.4%, though I did have one spike at nearly 75%. I thought that the low initial measurement might be because of leaving the charging cable coiled (it did feel warmer than the rest of the cable) but after getting a better percentage the first charge after uncoiling it went back to the same value I saw initially.

I'd like to believe the value Phil listed for my unmodified EVSE but I've been calculating total usage using the 71.4% value over in the Daily Grind.

I'll be crossing over the 1300mi mark today and I'm still extremely impressed and satisfied with the vehicle.

[herm]

thats a large difference... what voltage is your 120V running at?

[Right Lane Cruiser]

110V is what the Kill-A-Watt reads.