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Re: 2016 30 kWh Battery data

Posted: Fri Nov 13, 2015 2:45 pm
by pkulak
DaveinOlyWA wrote:interesting that there is the same 1.5 kwh more or less that is unavailable for use. I get about 28.4 kwh available. Either way, I am guessing the numbers will change a bit as the car gets broken in. very cool!
That would be using nearly 95% of the total capacity of the battery. I wonder if it's not really a 32 kWh battery, but Nissan chooses not to advertise it that way? That's not without precedent. Chevy never bothered to update the Volt EPA range numbers, probably in an effort to make the 2016 look as good as possible.

Re: 2016 30 kWh Battery data

Posted: Fri Nov 13, 2015 4:18 pm
by DaveinOlyWA
pkulak wrote:
DaveinOlyWA wrote:interesting that there is the same 1.5 kwh more or less that is unavailable for use. I get about 28.4 kwh available. Either way, I am guessing the numbers will change a bit as the car gets broken in. very cool!
That would be using nearly 95% of the total capacity of the battery. I wonder if it's not really a 32 kWh battery, but Nissan chooses not to advertise it that way? That's not without precedent. Chevy never bothered to update the Volt EPA range numbers, probably in an effort to make the 2016 look as good as possible.
ya, good point. a lot of speculation that the 2013 pack had unannounced changes and I was very surprised when LEAF Spy gave me 22.7 kwh available. so if we use a formula of 91.6% viewable capacity a 30 kwh battery should only have 27.5 kwh available but if the 2013 pack is still 24kwh (I personally don't think it is) it has a viewable capacity of 94.6% which means a 28.375 kwh available would be right on par with that. I think there is two things happening here. A better chemistry that allows the deeper cycling along with hidden capacity that Nissan has elected to not talk about

Re: 2016 30 kWh Battery data

Posted: Fri Nov 13, 2015 5:38 pm
by evnow
One possibility is that a certain *amount* of capacity is reserved and not a certain *percentage*.

Re: 2016 30 kWh Battery data

Posted: Fri Nov 13, 2015 11:14 pm
by QueenBee
evnow wrote:One possibility is that a certain *amount* of capacity is reserved and not a certain *percentage*.
But that doesn't really make sense does it? The top and bottom of the pack is all based on cell voltage. So they could have changed the cut off voltages?

Re: 2016 30 kWh Battery data

Posted: Sat Nov 14, 2015 1:58 am
by TimLee
QueenBee wrote:...
But that doesn't really make sense does it? The top and bottom of the pack is all based on cell voltage. So they could have changed the cut off voltages?
On the 2011 pack the top may be voltage limited, but the bottom turtle and pack disconnect are based on kWh remaining.
0.4 kWh reported by LEAF Spy Pro at Turtle.
0.3 kWh reported at Pack Disconnect.
(Unless you plug in EVSE before it gets there while it is still in Ready mode and then the 2011 will immediately do Pack Disconnect. Observed that today.
May have been intentional.
If that close to dead in the water and plugged in, best to keep the vehicle where it is and assume it can start charging.)

But amperage integrated over time is capacity. Close to voltage, but not necessarily the same depending on age of the cells and capacity degradation.

But if they changed limits on the new higher capacity pack, they are probably still doing the bottem end based on kWh Remaining.

Re: 2016 30 kWh Battery data

Posted: Sat Nov 14, 2015 2:06 am
by Turbo3
Charge cutoff voltage seems to be 394 volts which is the same as before.

Re: 2016 30 kWh Battery data

Posted: Sat Nov 14, 2015 7:36 am
by JeremyW
TimLee wrote:On the 2011 pack the top may be voltage limited, but the bottom turtle and pack disconnect are based on kWh remaining.
Well yes and no... Yes, you will see the gids/kWh remaining hit those numbers as you go lower in the voltage curve, but it's the LBC/BMS making the decision as to how much you can safely pull out without hitting the low voltage thresholds. Remember that the original "kWh remaining" message floating out on the bus is really for the leafs' subsystems and isn't as precise as you think. My former 2012 car had a weak cell pair that would cause gids to be unstable below ~45 (3.6kWh). I'd drop as much as 10 gids in a mile, other times I'd restart the car and gain 12 gids, hit turtle at 10 (!) gids once... it was bad.

Re: 2016 30 kWh Battery data

Posted: Sat Nov 14, 2015 8:58 am
by DaveinOlyWA
QueenBee wrote:
evnow wrote:One possibility is that a certain *amount* of capacity is reserved and not a certain *percentage*.
But that doesn't really make sense does it? The top and bottom of the pack is all based on cell voltage. So they could have changed the cut off voltages?
voltages do not address kwh stored. what we know is how many modules and cells there are but nothing more. cells can be any size. it is still possible to hide capacity by simply reprogramming SOC to only show what is available for use.

Re: 2016 30 kWh Battery data

Posted: Sat Nov 14, 2015 10:41 am
by QueenBee
TimLee wrote:
QueenBee wrote:...
But that doesn't really make sense does it? The top and bottom of the pack is all based on cell voltage. So they could have changed the cut off voltages?
On the 2011 pack the top may be voltage limited, but the bottom turtle and pack disconnect are based on kWh remaining.
Hmm, looks like more information has come in with regards to what the cut off is. I was pretty sure the original understanding was that it was a specific voltage of the lowest cell but seems like too much variation for that to be the only trigger based on your experience and others in this thread: http://www.mynissanleaf.com/viewtopic.p ... 80#p426253

Re: 2016 30 kWh Battery data

Posted: Sat Nov 14, 2015 7:10 pm
by TimLee
It will be interesting to see the frst 30 kWh battery LEAF Spy Pro data at Turtle and Pack Disconnect.
May be hard to find a dealer with a working DCQC that is willing to let you discharge it to dead in the water using the defroster at 90F :o :shock: :? ;)

My dealer is very understanding and helpful.
But probably not that much.
And their DCQC is dead in the water till further notice.
Been hard to get much Nissan response on their defective design DCQC.