My Nissan Leaf Forum

alozzy wrote:
A brand new pack is around 21 kWh useable, so LeafSpy SOH should be about 84% in the example. If instead it was >90% then a BMS reset would be a strong possibility.

Agree. Or 50 < Ahrs < 55

alozzy wrote:Having stated all of the above, a BMS reset on a 2013 would be pretty obvious anyways because virtually no 2013s are likely to have an SOH >90% at this point.

Agree, but probability not zero.

alozzy wrote: However, a used 2015 that was driven in a hot climate and had its BMS unscrupulously reset then exported across states, would be more likely to fool a potential buyer. That's because most 2015s in moderate climates would still have >93% SOH.

And your basis for that statement is? So your logic is that a higher SOH is more believable in cooler climate?

Alozzy is right about the SOH in my 2013 LEAF. It is at 89%
I have no idea how it will change in the next couple of months as winter thaws. Presumably somewhere between 85-95%

SageBrush wrote:Alozzy is right about the SOH in my 2013 LEAF. It is at 89%
I have no idea how it will change in the next couple of months as winter thaws. Presumably somewhere between 85-95%

Do you believe that a BMS reset can set the SOH to any value, e.g. 85%, other than just 100%?
It's possible that a BMS reset could have been done at some point in time and the vehicle driven such that the SOH is now 85-95%.

lorenfb wrote:

SageBrush wrote:Alozzy is right about the SOH in my 2013 LEAF. It is at 89%
I have no idea how it will change in the next couple of months as winter thaws. Presumably somewhere between 85-95%

Do you believe that a BMS reset can set the SOH to any value, e.g. 85%, other than just 100%?

No, and I do not understand how that is related to my post.

Regarding the reset, I'm under the impression that the initial read is 100% and then with driving over a few weeks (maybe a couple of months ?) the SOH settles down to the pre-reset value. So it is not the SOH value in and of itself (unless it is 100%) that makes a reset suspect, but a SOH value considerably higher than normative for the peer group.

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My car fits the mold of a reset: It arrived with a LeafSpy reading of 64 Ahr and 99.6% SOH, and over 6 months lost 10% of each value. I don't think my car had an intentional reset because the dealer showed me other cars with poorer readings and the current readings after 15 months of ownership are still quite good and at worse represent a pre-reset baseline. All in all, we are treading in very poorly understood waters.

In any case, my earlier post was meant to be a bit of humor: alozzy doubts a 2013 LEAF will be found that has over 90% SOH. My car *almost* meets the threshold (and obviously is not affected by any possible reset now.) And may yet, if the SOH improves as the weather warms up a bit.

SageBrush wrote:

lorenfb wrote:

SageBrush wrote:Alozzy is right about the SOH in my 2013 LEAF. It is at 89%
I have no idea how it will change in the next couple of months as winter thaws. Presumably somewhere between 85-95%

Do you believe that a BMS reset can set the SOH to any value, e.g. 85%, other than just 100%?

SageBrush wrote:No, and I do not understand how that is related to my post.

It was a general question, as some may believe such.

SageBrush wrote:Regarding the reset, I'm under the impression that the initial read is 100% and then with driving over a few weeks (maybe a couple of months ?) the SOH settles down to the pre-reset value.

Right, but not easy to do on the part of a Nissan dealer, i.e. putting miles on the Leaf. Yes, maybe an independent car lot if it had the time
and access to a Leaf diagnostic tool (Consult II) and whether that function can even be performed at the dealer level (without a logon to
Nissan corporate). Can you imagine what the press would do to Nissan, if it knew that were actually occurring at a dealer level?

SageBrush wrote:So it is not the SOH value in and of itself (unless it is 100%) that makes a reset suspect, but a SOH value considerably higher than normative for the peer group.

True.

SageBrush wrote:My car fits the mold of a reset: It arrived with a LeafSpy reading of 64 Ahr and 99.6% SOH, and over 6 months lost 10% of each value. I don't think the car had an intentional reset because the dealer showed me other cars with poorer readings and the current readings are still quite good. All in all, we are treading in very poorly understood waters.

Valid points.

SageBrush wrote:Alozzy is right about the SOH in my 2013 LEAF. It is at 89%
I have no idea how it will change in the next couple of months as winter thaws. Presumably somewhere between 85-95%

What build month is your 2013? As stated, this one I'm looking at is Feb.

briscobully wrote:

SageBrush wrote:Alozzy is right about the SOH in my 2013 LEAF. It is at 89%
I have no idea how it will change in the next couple of months as winter thaws. Presumably somewhere between 85-95%

What build month is your 2013? As stated, this one I'm looking at is Feb.

He undoubtedly has a later build "Wolf" pack. The earlier Canary pack wouldn't have 12 bars at this point under any conditions found outside of Northern Europe or Northern Canada, unless it was kept in an air conditioned garage and only driven in cooler weather..

My car is a 10/2013 build, so indeed it has the "wolf" pack

Rather than respond to all the comments about my test methodology, it's not intended to be super accurate. I know the on-board instrumentation isn't perfect...

It's only value is to a prospective buyer who is considering a LEAF that matches all these criteria:

• There are 12 capacity bars showing on the dash
• LeafSpy is showing a high SOH that would put the pack in the top 10% percentile or better
• A prospective buyer wants some peace of mind that the LeafSpy metrics are accurate and that the LEAF has not been tampered with (ie BMS reset)

It would be pointless to do a range test if LeafSpy shows 82% SOH, mediocre AHr, and there are 11 capacity bars on the dash - those numbers are obviously believable for an older LEAF. A BMS reset would result in much better metrics...

In other words, if LeafSpy is showing "too good to be true" metrics, then the range test will confirm if you just won the lottery or if the LEAF is a lemon.

Out of curiosity, I just checked the capacity of my 11 bar, 2013 S, using Alozzy's instructions. Did it exactly as he specified, except drove 60mph, not 50.
Got: starting soc=48, ending=23 =>25% used
distance=19.9 miles, efficiency=4.6
This gives: (19.9/4.6)x4=17.2 kwh capacity
17.2/21 (usable new pack)= 81% of new capacity

LeafSpy says 83% SOH. Looks like a good, no gadgets needed, way to get estimated battery pack capacity for those trying to be sure the battery in their prospective purchase is about what is showing (i.e. BMS reset was likely done if a car with the above results has all 12 bars).