alozzy
Posts: 712
Joined: Fri Jan 20, 2017 4:25 pm
Delivery Date: 18 Jan 2017
Location: Vancouver, BC
Contact: Website

Re: Best and Worst Case

Mon Oct 30, 2017 11:43 pm

I consider the range test as simply a means of catching a BMS reset, as LeafSpy alone can't protect against that.

I think it would be highly unlikely that an unscrupulous dealership would take the risk of doing a BMS reset on a car with 85% SOH or better, as most buyers would see 12 capacity bars on a car like that and would assume the battery was in good shape anyways...

By doing a range test on a 2 or 3 bar loser that had a BMS reset, it would be pretty obvious that the battery was lousy.

In other words, the range test doesn't have to be super accurate - its usefulness is in avoiding a Leaf that has great, but fake, LeafSpy stats due to a BMS reset.
Vancouver, CA owner of a 2013 Ocean Blue SV + QC, purchased 01/2017 in WA
Zencar 12/20/24/30A L1/L2 portable EVSE
1-1/4" Curt #11396 hitch
After market, DIY LED DRLs
LeafSpy Pro + Konnwei KW902 ELM327 BT OBDII dongle
Loving my first BEV :D

BuckMkII
Posts: 169
Joined: Sat May 06, 2017 8:04 am
Location: Seattle

Re: Best and Worst Case

Tue Oct 31, 2017 9:26 am

alozzy wrote:I consider the range test as simply a means of catching a BMS reset, as LeafSpy alone can't protect against that.

I think it would be highly unlikely that an unscrupulous dealership would take the risk of doing a BMS reset on a car with 85% SOH or better, as most buyers would see 12 capacity bars on a car like that and would assume the battery was in good shape anyways...

By doing a range test on a 2 or 3 bar loser that had a BMS reset, it would be pretty obvious that the battery was lousy.

In other words, the range test doesn't have to be super accurate - its usefulness is in avoiding a Leaf that has great, but fake, LeafSpy stats due to a BMS reset.

Good point. It doesn't matter for this purpose if the actual capacity is 19.5 kWh or 18.9 kWh. The question is whether the capacity is 19 kWh or 17 kWh.
2013 SV no QC, manufactured July 2013
car grew up in San Jose CA, purchased 5/31/17 in Seattle
on 6/16/17: AHr = 56.4; SOH = 86%; Hx = 84.3; ODO = 39,250
on 9/29/17: AHr = 55.3; SOH = 84%; Hx = 81.6; ODO = 41,492
bar 12 lost 8/21/17

eyemgh
Posts: 33
Joined: Thu Oct 26, 2017 1:32 am
Delivery Date: 26 Oct 2017
Location: Ashland, OR

Re: Best and Worst Case

Wed Nov 01, 2017 8:52 am

Well, after agreeing to all the terms, it was sold out from under me. So there's that. :(

I have a sneaking suspicion that EV sales are VERY seasonal, hence the significant price rise in the last 6 months. Back to looking mode. :D

SageBrush
Posts: 1495
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Best and Worst Case

Wed Nov 01, 2017 10:49 am

alozzy wrote:I consider the range test as simply a means of catching a BMS reset, as LeafSpy alone can't protect against that.

I think it would be highly unlikely that an unscrupulous dealership would take the risk of doing a BMS reset on a car with 85% SOH or better, as most buyers would see 12 capacity bars on a car like that and would assume the battery was in good shape anyways...

By doing a range test on a 2 or 3 bar loser that had a BMS reset, it would be pretty obvious that the battery was lousy.

In other words, the range test doesn't have to be super accurate - its usefulness is in avoiding a Leaf that has great, but fake, LeafSpy stats due to a BMS reset.

Yep!
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

SageBrush
Posts: 1495
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Best and Worst Case

Wed Nov 01, 2017 10:51 am

BuckMkII wrote:I should say that, while this sounds good on paper, I'm not totally convinced it's foolproof to do this on one test drive and say you "know" the capacity of the pack. Mine actually got a better score on my first try!

It is a pretty good test if 50%+ of the SOC is used during the test
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

alozzy
Posts: 712
Joined: Fri Jan 20, 2017 4:25 pm
Delivery Date: 18 Jan 2017
Location: Vancouver, BC
Contact: Website

Re: Best and Worst Case

Wed Nov 01, 2017 5:39 pm

@BuckMkII you said:

I should say that, while this sounds good on paper, I'm not totally convinced it's foolproof to do this on one test drive and say you "know" the capacity of the pack. Mine actually got a better score on my first try!


I'm not saying "do this one test", quite the opposite. I'm saying, use Leaf Spy to obtain the BMS stats AND use the range test to make sure that the BMS wasn't reset. Neither one, by itself, is reliable.
Vancouver, CA owner of a 2013 Ocean Blue SV + QC, purchased 01/2017 in WA
Zencar 12/20/24/30A L1/L2 portable EVSE
1-1/4" Curt #11396 hitch
After market, DIY LED DRLs
LeafSpy Pro + Konnwei KW902 ELM327 BT OBDII dongle
Loving my first BEV :D

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