DaveinOlyWA
Well-known member
LeftieBiker said:
You have LEAF Spy, right? How consistent are your full charge stats? GIDs, Ahr and kwh available? Cause mine are anything but
How often to "Cell Balance"? Weekly? Monthly? Depends?
- Thread starter ldallan
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Help Support My Nissan Leaf Forum:
You have LEAF Spy, right? How consistent are your full charge stats? GIDs, Ahr and kwh available? Cause mine are anything but
I'd have to go back and look. I mostly look at SOH, Hx (at first) and the balance and voltage differences.
DaveinOlyWA
Well-known member
LeftieBiker said:
:lol: Yeah, I know what you mean. I don't really look at Hx either any more
Reagle
Well-known member
My car had a bad battery cell (actually a pack of 2 I think) replaced at 8k miles a few months ago, and it still can't seem to get its balance back. the new cells are a good 80mV above the rest.. Any suggestions? I've been contemplating deep discharge but it's a hassle. I suppose I can try leaving it plugged in after charging for a while if most balancing happens at the tail end. Currently it's charged on the timer and usually is ready 30 minutes or so before I leave, so it never actually sits for a long time plugged in
If all three dash charging lights turn off, it's as balanced as the car will get it. You could try running it down to near Turtle Mode and then fully charging it.
Reagle
Well-known member
Yeah, by the time I leave no lights are on on the dash , and Chargepoint is not showing anything going on. ..
I called the dealership, but I might as well be talking to the wall when trying to explain to service advisor that my cell voltages are out of whack
I called the dealership, but I might as well be talking to the wall when trying to explain to service advisor that my cell voltages are out of whack
Nubo
Well-known member
Reagle said:
A couple of cells sitting 80mV above the others at the top end isn't really a problem, imo.
Just give it a good 100% charge and allow it to sit plugged in for a good 4 hours or so after charge completion. A few rounds of this may bring them closer in line but I wouldn't worry about it.
Reagle
Well-known member
Interesting, I tried that and I see four 5 minute pulses at the end where charge current goes to 0.6kw then to 0. In my daily use I see at most one of these,Once past 30 minutes though nothing is happening so far
I don't think that leaving it plugged in for hours past the end will add any charge. Smart chargers for smaller packs will do that, but AFAIK the Leaf decides that charging is over when the blue lights all go out.
Nubo
Well-known member
LeftieBiker said:
I thought it would bleed charge from the high cells with the shunt resistors. In any case I wouldn't worry about the new slightly higher cells. They're in no danger of being overcharged if they're only 80mv above the mean.
I don't see why it would need to be plugged in to do that.
DaveinOlyWA
Well-known member
Reagle said:
Question; How much of a reduction are you seeing in "full" charge range?
Do you need that full charge range?
If you answer is "not much" or "don't know" on the first and "No" on the 2nd, then don't worry about it. Eventually the pack will self balance. Balancing current is very low but will be on "all" the time.
The only real drawback is range at full will be hampered as the high cells will trigger BMS to shutdown early. There are a few things you can try but none would be good for the overall health of the pack so I would let it go.
Reagle
Well-known member
So far GOM range is unchanged after full charge, but Leafspy is reading lower SOC than the car reports. It used to be the other way around..
I can see this being a problem if these cells hit OV limit during charge before normal taper ends and that terminates charge early. But I suppose that should extend the life of the pack
Scary part is even the Leaf tech at the dealership has no idea what cell imbalance means
I can see this being a problem if these cells hit OV limit during charge before normal taper ends and that terminates charge early. But I suppose that should extend the life of the pack
Scary part is even the Leaf tech at the dealership has no idea what cell imbalance means
DaveinOlyWA
Well-known member
Reagle said:So far GOM range is unchanged after full charge, but Leafspy is reading lower SOC than the car reports. It used to be the other way around..
I can see this being a problem if these cells hit OV limit during charge before normal taper ends and that terminates charge early. But I suppose that should extend the life of the pack
Scary part is even the Leaf tech at the dealership has no idea what cell imbalance means
If you want LEAF Spy and the GOM to match, check it about 80% SOC
Not to steal a weather analogy but if you don't like what you see in LEAF Spy, just wait a minute.
In both cases, neither the weather or LEAF Spy is to blame. LEAF Spy reports the true state of the pack so when fully charged, the GOM will say 100% which is the "usable" charge while LEAF Spy may say 97% which is the actual charge. Now if that is all there is, then no problem.
BUT....
Nissan, like ALL car manufacturers sees fit to build in a reserve and also feels we are not mature enough to know about that reserve so its hidden.
This means the LEAF Spy SOC starts out a few points below the GOM SOC but by the time the GOM starts blinking, LEAF Spy will be 10 points up.
Starting on the 40 kwh, Nissan added another low pack "alert" where the SOC meter goes from 2% to "_ _ _" which happens around 38-40 GIDs.
https://daveinolywa.blogspot.com/2019/05/april-2019-drive-report-now-that-my.html
Tsiah
Well-known member
The pack shunts cells any time there is an imbalance in the pack, not just during charging.specialgreen said:
Tsiah said:
This is correct.... as far as I can tell there is no top bottom or charge balancing on the leaf - it is in a continuous state of balancing. When you charge to 100% charging stops when any 1 cell reaches maximum - regardless of other cells being low.
