The 40KWH Battery Topic

[LeftieBiker]

Have not checked the battery temps after DCFC. On our 40 kWh Leaf there don't seem to be discrete bars like our prior 30 kWh Leaf. On the few times I have looked, the battery was not in the red zone.

It has the same 12 temp bars, but they have no delineated borders, and so they look like they have infinite variability. They don't.

[SageBrush]

Yes but free.
If we owned the vehicle instead of leased again (3 year), and knowing the Leaf battery history, yeah would likely avoid that entirely.

To quote Bjorn Nyland: "Free charging is the DEVIL !."

People do all sorts of things when something is free of charge that otherwise run contrary to reasonable or smart behavior.

I wonder how much the LEAF battery degradation saga can be ascribed to the NCTC program

[LeftieBiker]

I used it only in Winter.

[cwerdna]

Yes but free.
If we owned the vehicle instead of leased again (3 year), and knowing the Leaf battery history, yeah would likely avoid that entirely.

To quote Bjorn Nyland: "Free charging is the DEVIL !."

People do all sorts of things when something is free of charge that otherwise run contrary to reasonable or smart behavior.

I wonder how much the LEAF battery degradation saga can be ascribed to the NCTC program

LOL. I love free charging. L2 charging is free at my work but we're not supposed to go to the office unless we have a really good reason to (long story). Since lockdown in mid-March, I've charged at work only twice when I went into pickup some devices when nobody was around.

I'd much rather use free charging (e.g. https://drivethearc.com/ for limited parts of Nor Cal, CCS recently quietly added to their free charging program) and some free L2 charging about 5 miles from home when I'm out (and can make it to the head of the ChargePoint wait list) and have time than pay over 31 cents/kWh marginal rate on Pacific Gouge & Extort. I try to get something done in my car during that time (e.g. eat, clean up junk mail, catch up on email, reading, watching videos, etc.)

Heck, I'd rather pay 18 cents/minute to charge on EA when my Bolt's below 55% SoC as it comes out to about 18 cents/kWh (not including $4/mo Pass+ fee) than to charge at home.

I'd imagine that NCTC at least helped fund EVgo and keep their per kWh costs under control at many locations to help balance out the demand charges. From what I understand, if a DC FC site (w/o energy storage to keep the peak demand down) is barely used but used at least once in a month, the resulting demand charges make the effective price per kWh super high.

[danrjones]

Charging habits is an interesting thing. Right now I charge at night at home because its the cheapest power I can get - my night rate is about 15 cents per KWh. I have a small solar system but that daytime power is far more valuable putting into the grid, as grid day costs are as high as 48 cents or similar. But I'm in the planning stages to add additional solar. Once I get MORE solar, it might be cheapest for me to charge during the day. Under NEM 2.0 its cheapest to use your own power rather than to take any power from the grid. If only TESLA power walls weren't so expensive. A Powerwall starts at 6k (or is it 6.5?) for 13.5 KWh not including extra costs. That's $444++ per KWh. Not quite the $100 we all dream of, yet.

[SageBrush]

That's $444++ per KWh. Not quite the $100 we all dream of, yet.

It is still expensive, but perhaps not as much as first blush suggests
I think the powerwall is good for a lifetime of 10 years full operation equivalent, so
365 days a year
1 kWh a day
10 years
= 3650 kWh. At a cost of 44,400 cents, that is 44,400/3650 = 12.1 cents a kWh

If you cycle to 70% DoD my WAG is a halving of degradation rate. That would extend the lifetime and financing costs but it would also reduce the straight per kWh cost by 1.4x to 12.1/1.4 = 8.6 cents a kWh. For people who do not have the opportunity to charge during the daytime when the PV is producing, that is still cheaper than dirty night time electricity from the grid.

----
Absolutely, get more PV !
You will always find a use for PV generation during the day: heat or cool your house, heat up the hot water tank, charge your EV, use appliances ...
Or just hit your utility for high daytime NEM rates
Do keep in mind though that CA is moving peak hours to later in the day, so west facing PV will be more valuable as a NEM product

[danrjones]

That's $444++ per KWh. Not quite the $100 we all dream of, yet.

It is still expensive, but perhaps not as much as first blush suggests
I think the powerwall is good for a lifetime of 10 years full operation equivalent, so
365 days a year
1 kWh a day
10 years
= 3650 kWh. At a cost of 44,400 cents, that is 44,400/3650 = 12.1 cents a kWh

If you cycle to 70% DoD my WAG is a halving of degradation rate. That would extend the lifetime and financing costs but it would also reduce the straight per kWh cost by 1.4x to 12.1/1.4 = 8.6 cents a kWh. For people who do not have the opportunity to charge during the daytime when the PV is producing, that is still cheaper than dirty night time electricity from the grid.

----
Absolutely, get more PV !
You will always find a use for PV generation during the day: heat or cool your house, heat up the hot water tank, charge your EV, use appliances ...
Or just hit your utility for high daytime NEM rates
Do keep in mind though that CA is moving peak hours to later in the day, so west facing PV will be more valuable as a NEM product

Yes, I'me going to put at least half facing west. Even then SCE is moving to 4-10pm or 5-9pm or similar, so that's where solar cuts off and a power wall dumping power out each evening would be helpful.

[danrjones]

No updates in this thread for awhile, I guess everyone has those "+" models now!

Stats as of this AM, the summer keeps chipping away at my SOH.

SOH: 89.45%
AMPHr: 103.26
Hx: 108.43
Mileage: ~ 6800 miles

IF, and that's a big IF, I have any more of those 3 month adjustments the next one would be around Sept 18th.
But not sure I will have any more of those as my last one in June was basically nothing.
The summer definitely seems to impact the battery, or the BMS, as I am loosing .01 or even .02 SOH each day.

Quick morning update:

SOH: 89.37%
AMPHr: 103.17
Hx: 108.27
Mileage: ~ 6920 miles

Temps in the batteries went below 100f this am for the first time in about a week. Looks like I've lost just under 0.01 per day since last update.

[rogersleaf]

At 15,000 miles at 1 week past 7 months ownership

LS stats:
AHr... 109.9
SOH... 95.2%
Hx... 115.38%
SOC... 98.6% and 479 GID
403.47v, cells balanced between 4.201-4.206v
odo... 15118
8 QC / 390 L2’s

At 10 months and 20,000 miles

LS stats:
AHr... 108.66
SOH... 94.13%
Hx... 121.84%
SOC... 98.2% and 471 GID
402.42v, cells balanced between 4.190-4.192v
odo... 20196
14 QC / 524 L2’s

Main difference in charging behavior and usage is due to cold weather. The car is getting charged to 100% daily using the timers so that charging completes about an hour before needing to leave on my commute. Then, the car's pre-heat timer is set so it's warm when leaving. Most nights the car is inside an attached garage.

At just under 14 months and 25,000 miles

LS stats:
AHr... 107.38
SOH... 93.03%
Hx... 117.59%
SOC... 98.8% and 469 GID
403.72v, cells balanced between 4.204-4.207v
odo... 25,072
18 QC / 652 L2’s

A bit overdue posting the last set of data. Pulled this last week.
I'm at 17 months now, 30,000 miles.
Looks like almost no capacity loss since the last time and GIDs are up by 2, find that hard to believe.
Must have found the fountain of youth.

LS stats:
AHr... 107.35
SOH... 92.99%
Hx... 109.64%
SOC... 99.2% and 471 GID
404.06v, cells balanced between 4.207-4.212v
odo... 30,271
20 QC / 772 L2’s

[DaveinOlyWA]

At 10 months and 20,000 miles

LS stats:
AHr... 108.66
SOH... 94.13%
Hx... 121.84%
SOC... 98.2% and 471 GID
402.42v, cells balanced between 4.190-4.192v
odo... 20196
14 QC / 524 L2’s

Main difference in charging behavior and usage is due to cold weather. The car is getting charged to 100% daily using the timers so that charging completes about an hour before needing to leave on my commute. Then, the car's pre-heat timer is set so it's warm when leaving. Most nights the car is inside an attached garage.

At just under 14 months and 25,000 miles

LS stats:
AHr... 107.38
SOH... 93.03%
Hx... 117.59%
SOC... 98.8% and 469 GID
403.72v, cells balanced between 4.204-4.207v
odo... 25,072
18 QC / 652 L2’s

A bit overdue posting the last set of data. Pulled this last week.
I'm at 17 months now, 30,000 miles.
Looks like almost no capacity loss since the last time and GIDs are up by 2, find that hard to believe.
Must have found the fountain of youth.

LS stats:
AHr... 107.35
SOH... 92.99%
Hx... 109.64%
SOC... 99.2% and 471 GID
404.06v, cells balanced between 4.207-4.212v
odo... 30,271
20 QC / 772 L2’s

Looks like you might have had a small bump up in there that masked the general degradation since .04% loss in 3 months is bit tough to believe. Now, .4 or .5 I can believe. I think my smallest 3 month spread was in the .3 range?