The 40KWH Battery Topic

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DougWantsALeaf said:
If they had just build a couple head sinks and a fan into the 62kw design, it would have killed most of the whining about the car battery.

Is that like Torgo's executive powder? A Nissan executive in every Leaf?
 
DaveinOlyWA said:
FYI; the full rate on "most" chargers around here at 90% SOC would be higher than 44 KW. That is only 366 volts. Do you have a charge curve you can post?
I'm afraid I don't have charge curves. We almost never stay with the car while it's charging, and I've found that LeafSpy loses its connection after a minute or so if the car is turned off. Do you have a trick to keep it recording while you are away?

I was actually surprised to see ~44kW above 90% SoC. With previous Leafs I thought it would only get about half that above 85%. Have I mis-remembered the typical charge taper?
 
Astros said:
DaveinOlyWA said:
FYI; the full rate on "most" chargers around here at 90% SOC would be higher than 44 KW. That is only 366 volts. Do you have a charge curve you can post?
I'm afraid I don't have charge curves. We almost never stay with the car while it's charging, and I've found that LeafSpy loses its connection after a minute or so if the car is turned off. Do you have a trick to keep it recording while you are away?

I was actually surprised to see ~44kW above 90% SoC. With previous Leafs I thought it would only get about half that above 85%. Have I mis-remembered the typical charge taper?

Plus could be different although I doubt it. The 40 kwh LEAF would be well less than half that rate.
 
Looks like i just finished my second big adjustment since i have had the car. As already mentioned I'm not sure these numbers reflect reality. But if they do, my battery is dropping like a rock. I've had the car for about 4 months. We just hit ~ 1500 miles.

Date SOH AMPHr Hx
5/03/2019 97.63 112.70 97.50
5/06/2019 97.62 112.69 97.94
5/07/2019 97.61 112.68 98.03
5/10/2019 97.60 112.67 98.39
5/13/2019 97.59 112.66 98.55
5/15/2019 97.58 112.65 98.73
5/19/2019 97.57 112.63 98.84
5/27/2019 97.55 112.61 99.27
6/01/2019 97.53 112.59 99.61
6/04/2019 97.50 112.55 100.12
6/11/2019 97.44 112.48 101.03
6/12/2019 97.43 112.47 101.25
6/13/2019 97.42 112.46 101.25
6/14/2019 96.49 111.39 101.58
6/15/2019 96.28 111.15 101.58
6/16/2019 95.64 110.41 101.67
6/17/2019 95.42 110.15 101.82
6/19/2019 95.40 110.13 102.15
6/20/2019 95.38 110.11 102.25
7/15/2019 95.19 109.89 103.22
7/24/2019 95.10 109.78 104.04
8/11/2019 94.90 109.55 104.95
8/30/2019 94.73 109.36 106.05
9/05/2019 94.68 109.30 106.27
9/10/2019 94.65 109.26 106.45
9/11/2019 94.64 109.25 106.48
9/12/2019 94.50 109.09 106.47
9/13/2019 93.73 108.20 106.48
9/14/2019 93.30 107.71 106.45
9/15/2019 93.29 107.69 106.45
 
I am curious, to anyone / everyone that has a 2018 40, what is the lowest SOH that anyone has?

Mine today is sitting at SOH 93.29%, AHr = 107.69. HX = 106.40%. 17 mV on the Shunting Screen (What is normal for the cell disparity anyway?)

3 QC's (none that I did) and 101 L1/L2 (not sure that is right either)
 
If you plot out my data, the big drop is EXACTLY 3 months apart, just like someone else here said it would be . My next drop should be on Dec 12-14th.

This whole thing sure looks like a computer is controlling the curve rather than simply reporting data. You SOH drops exactly 0.01% every day no matter what, then every 3 months like clockwork it must re-compute / evaluate the data its been collecting. But does that mean it artificially adjusts your capacity at that three months interval, or it simply "catches up" to reality that existed based on your heat and usage?

It looks really artificial in nature.

Anyone remember apple getting caught artificially down rating phone batteries? They said it was to keep the phone optimized, but many suspected it was to push you toward buying a new product. Of course Nissan also has to be able to honor their warranty, which is 8 years / 1000,000 miles promised to what, 70% of original capacity? You'd think artificially down-rating would be a dumb thing to do.
 
Which raises an interesting question- are ev makers allowed to artificially derate your battery? Obviously they are held to the warranty, but anything else?
 
I haven't seen that big 3 month drop. I had a decent sized drop from May to June after getting the car in mid-march but no corresponding August to September. I'll keep checking every month and post my results.

Date SOH% SOH %Chg Ahr Ahr %Chg TempF

3/15/19 97.47 -2.53% 112.52 -2.53% 69.1
4/15/19 97.41 -2.59% 112.45 -2.59% 75.2
5/15/19 97.34 -2.66% 112.37 -2.66% 82.2
6/15/19 95.38 -4.62% 110.11 -4.62% 90.8
7/15/19 94.98 -5.02% 109.64 -5.02% 97
8/15/19 94.63 -5.37% 109.24 -5.37% 101.8
9/15/19 94.41 -5.59% 108.99 -5.59% 92.2
 
It looks like you had one between may and June, but to know for sure you have to almost check daily.

Then again you could have a different bms software version. Who knows!
 
golfcart said:
I haven't seen that big 3 month drop. I had a decent sized drop from May to June after getting the car in mid-march but no corresponding August to September. I'll keep checking every month and post my results.

Date SOH% SOH %Chg Ahr Ahr %Chg TempF

3/15/19 97.47 -2.53% 112.52 -2.53% 69.1
4/15/19 97.41 -2.59% 112.45 -2.59% 75.2
5/15/19 97.34 -2.66% 112.37 -2.66% 82.2
6/15/19 95.38 -4.62% 110.11 -4.62% 90.8
7/15/19 94.98 -5.02% 109.64 -5.02% 97
8/15/19 94.63 -5.37% 109.24 -5.37% 101.8
9/15/19 94.41 -5.59% 108.99 -5.59% 92.2

:shock:

Holy sheepdip! Hate to see your definition of a big drop...

I would put nothing into these readings. I fear that Nissan has changed BMS programing to thwart LEAF Spy. FYI; the adjustment doesn't always go down.
 
DaveinOlyWA said:
golfcart said:
I haven't seen that big 3 month drop. I had a decent sized drop from May to June after getting the car in mid-march but no corresponding August to September. I'll keep checking every month and post my results.

Date SOH% SOH %Chg Ahr Ahr %Chg TempF

3/15/19 97.47 -2.53% 112.52 -2.53% 69.1
4/15/19 97.41 -2.59% 112.45 -2.59% 75.2
5/15/19 97.34 -2.66% 112.37 -2.66% 82.2
6/15/19 95.38 -4.62% 110.11 -4.62% 90.8
7/15/19 94.98 -5.02% 109.64 -5.02% 97
8/15/19 94.63 -5.37% 109.24 -5.37% 101.8
9/15/19 94.41 -5.59% 108.99 -5.59% 92.2

:shock:

Holy sheepdip! Hate to see your definition of a big drop...

I would put nothing into these readings. I fear that Nissan has changed BMS programing to thwart LEAF Spy. FYI; the adjustment doesn't always go down.

I haven't seen that big 3 month drop

I had a big drop from May to June, did not see one 3 months later from August to September... unless you consider going from 109.24 Ahr to 108.99 Ahr a big drop.

You had posted this back in July that you expected updates to happen every 90 days... which I did not see.

DaveinOlyWA said:
No rush. Adjustments come every 90 days. You can simply wait till Sept. I will say a .15-.25% loss in July with same for August...
 
Which one doesn't always go down?

My Hx doesn't always go up. It just ticked down very slightly the last two days. SO FAR my SOH always has gone down.

But I agree, its all so artificial, I think its a BMS software thing more than real battery degradation.
It did cause me to ask if Nissan, or any company for that matter, has the right to artificially reduce your battery life.
I pointed out apple was caught doing essentially that to phones.

I have a nice plot of my SOH including the two drops but I guess I can't directly post it.

It also makes me wonder if the SOH we are all watching in leafspy is even a good measure of the battery health bars in the 2018/2019s.
I tried finding the battery health bar in the the manual to see what they said about it and actually couldn't find it. It seems it was only called out by name in the warranty.
 
danrjones said:
Which one doesn't always go down?

My Hx doesn't always go up. It just ticked down very slightly the last two days. SO FAR my SOH always has gone down.

But I agree, its all so artificial, I think its a BMS software thing more than real battery degradation.
It did cause me to ask if Nissan, or any company for that matter, has the right to artificially reduce your battery life.
I pointed out apple was caught doing essentially that to phones.

I have a nice plot of my SOH including the two drops but I guess I can't directly post it.

It also makes me wonder if the SOH we are all watching in leafspy is even a good measure of the battery health bars in the 2018/2019s.
I tried finding the battery health bar in the the manual to see what they said about it and actually couldn't find it. It seems it was only called out by name in the warranty.

My SOH and ahr has either stayed the same or went down EVERY TIME except my July adjustment when they went up gaining 1¼%.
 
LeftieBiker said:
Which one doesn't always go down?


With previous generation battery packs, the SOH will go up occasionally, like after a QC session. We do have one lonely instance of a 40kwh pack SOH going up - a little, once.

I have this picture in my head of some tech guy as Nissan sitting around laughing at us for watching leafspy every day.

But those battery health bars must be connected to something. When Nissan does a service, what exactly do they print out and give you?
I read here somewhere that someone had a five star battery rating. Is that all you get?
 
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