DaveinOlyWA
Well-known member
DougWantsALeaf said:
Not sure I would even care about 30 mV. That is far from "out of balance"
The 62kWh Battery Topic
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Not sure I would even care about 30 mV. That is far from "out of balance"
If you have 30 mV delta at full charge, that is a little higher than normal. As Dave said, it is not bad so don't worry about it. A deep discharge might change the numbers a little and help the LBC learn the battery characteristics better, but I doubt that it will make any long-term difference.
If it is a bad cell, it will get worse no matter what you do.DougWantsALeaf said:
If it is a good cell, it will not get worse, will not be a significant affect on the battery pack, and will jump around
It is possible that sometime in the future that cell will transition to a clearly bad cell. You will then look back and say that the warning signs were already apparent today. But you cannot change the future course of the cell by anything you do today. You might be able to obscure the mv difference today but that will not change the underlying cell chemistry or long term performance.
DougWantsALeaf
Well-known member
My S+ had a fairly brutal BMS adjustment; -1.5% it's now down to 93.86% which is only a 1/2% above the SV+. Cars were made only a few months apart so if bms movements are largely time based, then I guess it makes sense.
I am not sure if charging patterns matter much.
I am not sure if charging patterns matter much.
DaveinOlyWA
Well-known member
DougWantsALeaf said:
I don't believe the SOH is a good indicator of battery degradation. A steady drop I can believe; whether slow, in steps like we see, or whatever. This is how batteries are supposed to work but to see 3-4 drops and then an increase?
The timing of the increases are also suspect. Are you seeing yours in Summer? During periods of greater demand? Interesting that the BMS would allow more capacity to be used just to take it back come Winter and lower driving demand?
We already know from the 30 kwh LBC debacle the BMS doesn't know the state of the pack. Its entire actions are based on what the LBC tells it. Can we equate Bush's war actions to his advisor's claims of WMD?
DougWantsALeaf
Well-known member
I am beginning to think you might be right. I happened to charge to 100% around the time of adjustment to try to balance my cell. The max gids (717) was the same then as the adjust empty started as it was today when I charged to 100% (I had a 123 miles drive this afternoon to get my daughter a vaccine, so figured why not); even though my SoH was 1.5% lower today. Not sure what any of it means.
The drive was 67 miles each way, mainly freeway (60 and 65) and fast highway (55). Outbound was an astounding 5 miles/kWh in spite of 45-50F ambient. The way home was more wind facing, and pulled in at 4.4, though was driving a little faster. Per LS 51% remaining after 123 miles. First 4 miles and final few miles were at slower speeds. No heat or ac needed for the drive.
Interesting that Edmunds shows the Leaf (with 17") as having more range than a 2020 SR+, even with buffer. Our S+ do even better.
https://www.reddit.com/r/electricvehicles/comments/md16um/more_reliable_numbers_than_epa_at_least/?utm_medium=android_app&utm_source=share
I liked their 65mph test procedure. It doesn't get much more objective than that.
https://youtu.be/m4IJGMilsqk
The drive was 67 miles each way, mainly freeway (60 and 65) and fast highway (55). Outbound was an astounding 5 miles/kWh in spite of 45-50F ambient. The way home was more wind facing, and pulled in at 4.4, though was driving a little faster. Per LS 51% remaining after 123 miles. First 4 miles and final few miles were at slower speeds. No heat or ac needed for the drive.
Interesting that Edmunds shows the Leaf (with 17") as having more range than a 2020 SR+, even with buffer. Our S+ do even better.
https://www.reddit.com/r/electricvehicles/comments/md16um/more_reliable_numbers_than_epa_at_least/?utm_medium=android_app&utm_source=share
I liked their 65mph test procedure. It doesn't get much more objective than that.
https://youtu.be/m4IJGMilsqk
knightmb
Well-known member
Yeah, just my experience with my 2020 SL Plus, when the battery level reaches 0%, there is still 9 kWH of power left (according to LeafSpy), so if you really had some gentle driving, you could stretch out another 30 to 40 miles but I haven't seen anyone do a 100% to dead test just yet to see how far one could really go in say an emergency trying to reach the next QC.DougWantsALeaf said:
cwerdna
Well-known member
Do you mean 9 kWh of energy?knightmb said:
If you were limited to 9 kW of power, you'd barely be able to accelerate and couldn't stay at a very high steady-state speed.
It's easy enough to use LeafSpy to measure the energy going into the battery during a charging session. Just pick a day when the battery is say 60 - 70F, start from a depleted battery and charge to full.DaveinOlyWA said:
knightmb
Well-known member
cwerdna said:
LOL, I did fix the typo because you'll notice it doesn't show an edit time on my post, but you must have caught that in the minute before I did the edit, but yeah, I know what you mean.
DaveinOlyWA
Well-known member
knightmb said:
Sure it was 9? I charted the relationship between the dash and LEAF Spy but was wondering if the relationship changes with degradation? I am likely going to do it again this Summer to compare.
https://daveinolywa.blogspot.com/2020/06/e-plus-summer-range-test.html
DaveinOlyWA
Well-known member
SageBrush said:
How does that show anything? If the BMS is controlling access to the pack? I NEVER used SOH as a determination of capacity anyway. Always used ahr. SOH is the layman's tool for people who don't know what the starting ahr was. I always had new cars so it didn't make sense to use SOH
DaveInOly said:
Not "anything", it measures pack capacity.
Coloumb counting and pack voltage are the base measurements your Ahr estimate relies on.
The Ahr reading is an estimate because it extrapolates from partial charges and discharges
When you measure total energy into the pack from depleted to full SoC via Leafspy, it is akin to having a utility meter attached to your EVSE -- only better, since you don't have to wonder about charging losses.
DaveinOlyWA
Well-known member
SageBrush said:
Ok, that is far from my understanding which begs the question has the process changed since the 30 kwh battery days? Because the BMS restricted access to "good" capacity because the LBC reported it as bad. So the fix was correcting errors in the LBC so it could correctly report the true condition of the pack to the BMS so it sounds like the BMS did no counting
The energy into the pack displayed by Leaf Spy is calculated from parameters read directly from the LBC so it is no more accurate than any of the other parameters Leaf Spy displays. The only way to measure the true useable battery capacity is to measure the charging energy from dead to full with an accurate external meter (using the same EVSE). I have been doing that for the replacement battery in my 2019 every 3 months and did it monthly for my 2015 and the replacement battery in the 2011. In all cases, the energy storage capacity of the battery (as measured by my external meter) tracked the AHr and "GIDs" quite well. The SOH also tracked the present AHr as a percentage of the initial AHr so the LBC does a fairly good job of tracking/reporting this information.SageBrush said:
DougWantsALeaf
Well-known member
March is in te books. We did have a few warm days in the mid 60s and many days in the 40s (and 30s).
S+ 658 miles 4.8-4.9 miles/kWh including a pretty reasonable amount of 60-65 mph highway. It's early, but it does feel like the EV01s are helping a little.
SV+ 385 miles. 4.3 miles/kWh With some, but less highway than the S+.
S+ 658 miles 4.8-4.9 miles/kWh including a pretty reasonable amount of 60-65 mph highway. It's early, but it does feel like the EV01s are helping a little.
SV+ 385 miles. 4.3 miles/kWh With some, but less highway than the S+.
DaveinOlyWA
Well-known member
Spring is arriving. I am only doing comfort controls (seat heater/steering wheel) in the mornings now so saving a "massive" 130ish watts of energy but the real kicker is no headlights coming or going. All this combined to push me to 4.17 miles/kwh for the month of March. I also noticed a 4 mph increase in average speed on commute days. Must be all that extra range playing tricks on my foot :lol:
I did lose another chunk of battery... .04% gone forev.... well, gone for now
I did lose another chunk of battery... .04% gone forev.... well, gone for now
DougWantsALeaf
Well-known member
A .04 adjustment is a win for sure.
DaveinOlyWA
Well-known member
DougWantsALeaf said:
Win? That is only on plus adjustments. This I call a closely fought but lost battle that could have been a coin toss especially when considering Nissan instrumentation.
DougWantsALeaf
Well-known member
Here is a 2 year report on a battery in the outback down under. Its still above 94%. I am beginning to think the 62 actually prefers warmer weather.
https://youtu.be/sezcdXpessw
https://youtu.be/sezcdXpessw