finman100
Posts: 324
Joined: Thu Sep 20, 2012 10:42 am
Delivery Date: 06 Jun 2014
Location: Albany, OR

Re: Near Turtle to cells balanced: 20.8 kW with 2015 Leaf with 24 kW battery: Low kW? As expected? Battery losing capaci

Thu Mar 01, 2018 10:43 am

I concur with the T-Rex chasing. Best to drive as far and as fast as u can in your Leaf, regardless of battery health and longevity. But, if their eyesight is based on movement, then...
Albany, Oregon
2014 Silver SV with charge/LED package. June 2014, I'm in the EV game!
46,000 miles
17.5 kWh on 100% charge (51-ish Ah), down 1 bar
4.2 miles/kWh average
Best trip: all of 'em. They're all no-gas!

ldallan
Posts: 18
Joined: Mon Jan 16, 2017 10:15 am
Delivery Date: 31 Dec 2016
Leaf Number: 000000

Re: Near Turtle to cells balanced: 20.8 kW with 2015 Leaf with 24 kW battery: Low kW? As expected? Battery losing capaci

Thu Mar 01, 2018 1:49 pm

cwerdna wrote:
But yes, get it down to turtle or almost turtle then run the heater at full. viewtopic.php?p=149528#p149528 is what the famed Ingineer did.


Thanks for the link. I figured my "work-around" of having the heat-on was "re-inventing the wheel". ;-)

Ingineer wrote:I pulled into my garage and continued to move back and forth with CC still on high heat, and finally the car performed an auto Ig-off. (Battery Contactor Opened) It went into the same mode as you would with 2 power switch presses w/o the brake.


I'm unclear why he moved the car back and forth while in the garage. rather than just leaving in Park with the heat on full blast.

I suppose CC means "Climate Control"?

Regarding "cells shorting out", that may be obsolete information from vehicles with less sophisticated BMS (battery management systems).

In any case, I'm not inclined to go to "battery flat", especially without Leaf-Spy installed. (which I probably ought to obtain and get a compatible ELM-327)

ldallan
Posts: 18
Joined: Mon Jan 16, 2017 10:15 am
Delivery Date: 31 Dec 2016
Leaf Number: 000000

Re: Near Turtle to cells balanced: 20.8 kW with 2015 Leaf with 24 kW battery: Low kW? As expected? Battery losing capaci

Thu Mar 01, 2018 1:59 pm

Levenkay wrote: You could drive into your garage under Turtle, put the car in Park, and crank the climate control up with the windows open. Might take awhile to fully deplete the battery, but at least you'd know it was within reach of a charger when it shuts down.


Agree with running the heater to drain the battery without the risk of having to push or tow the car to a charger.

My less-than-informed speculation is that running the heater might be the equivalent of driving at 10 mph or so. I have been curious about how much drain the heater puts on the battery. I've done relatively controlled tests on an 11 mile loop at speeds from 45 to 70 mph at about 15° F with the heater on and off, and it made a significant difference. But I didn't wrestle with the math to get more specific. Mea culpa?

The amount of battery drain from the heater while in PARK might be something Leaf-Spy could reveal.

ldallan
Posts: 18
Joined: Mon Jan 16, 2017 10:15 am
Delivery Date: 31 Dec 2016
Leaf Number: 000000

Re: Near Turtle to cells balanced: 20.8 kW with 2015 Leaf with 24 kW battery: Low kW? As expected? Battery losing capaci

Thu Mar 01, 2018 2:28 pm

powersurge wrote:I don't understand the fascination with how many KWH we can put into the battery, or other things after we reach turtle mode??


I suppose it could be a matter of how much we want to Grok what is going on with our Leafs.

This time, I didn't intentionally drive until near "Turtle Mode", but since it happened, it seemed like a "why not" to measure how my kWH got put into the battery.

With the used Leaf being a lease-turn-in, and now that it has over 30,000 miles and still at 12-bars, I thought it might give me a hint on how far away it might be until 11-bars.

Quick version... don't run the car to turtle mode unless you need to drive to the hospital to save a life, or a T-Rex is chasing you. Otherwise, take care of your car and do experiments with cheaper items......


I rarely drive until "Turtle Mode", but we can "agree to disagree" on just how bad of an idea it is to drive to the point of getting to "Turtle Mode". Are you recommending to have the Leaf towed if the Very Low Battery warning is reached (both GOM and Percent are blinking)? Unless it was a medical emergency or T-Rex?

I would describe my driving practices as "baby'ing the battery", but not that much. Certainly, I've never been in the situation of having the Leaf towed, or having to push it.

PS - You don't "balance" your battery cells by going down to 0% battery, no matter what anyone has told you.


We are in "heated agreement" ... perhaps I was unclear for you to think that I was suggesting that "cell balancing" was related to getting the battery to ultra low or even to 0%. If so, my apologies.

FWIW:
My impression with laptops that may or may not extrapolate to the Leaf battery: it is "life in the real world" to have the laptop battery get to being completely drained. That seems to have the indirect benefit of helping the laptop system estimate battery life remaining, and maybe how long to full charge.

But we are probably also in "heated agreement" that there is a big difference between a $100 laptop battery that can be replaced, and a Leaf battery that might cost $5000 to $10,000 to replace. Ouch.

ldallan
Posts: 18
Joined: Mon Jan 16, 2017 10:15 am
Delivery Date: 31 Dec 2016
Leaf Number: 000000

Re: Near Turtle to cells balanced: 20.8 kW with 2015 Leaf with 24 kW battery: Low kW? As expected? Battery losing capaci

Thu Mar 01, 2018 2:44 pm

cwerdna wrote:In Edmunds testing at https://www.edmunds.com/nissan/leaf/201 ... r-end.html, when doing 35 mph, it looks like they hit VLBW (2nd warning) at 122.0 miles. Turtle came on a 130.0 miles and I'm guessing the contactor opened at 131.2 miles, at which point they steadily lost speed until car halted at 132.0 miles.


Thanks for the Link, and your interpretation.

That surprises me that there might be only 1 or 2 or 3 miles remaining after "Turtle Mode" reached, so I will be more careful in the future. I REALLY don't want to push the Leaf.

Also, there could be differences between the different model years, as you mention.

And if I stay in the mode of "Inquiring Minds Want to Know", I almost certainly should get Leaf-Spy and a compatible ELM-327.

OT? Thread-drift?
Am I the only one who is paranoid enough to worry about potential hacking with Leaf-Spy software that can apparently "Write" values to the car, such as windshield wipers, etc. I would prefer a less powerful Leaf-Spy that was "Read-Only".

SageBrush
Posts: 2399
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Near Turtle to cells balanced: 20.8 kW with 2015 Leaf with 24 kW battery: Low kW? As expected? Battery losing capaci

Thu Mar 01, 2018 5:21 pm

ldallan wrote:I'm pondering how to interpret that.

To summarize:
You don't know the charging efficiency;
You don't know the energy amount reserved, or the usable in the battery at the start of the charging.

But you think 20.8 kWh from the meter is a concern.
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Car is now enjoying an easy life in Colorado
3/2018: 58 Ahr, 28k miles

LeftieBiker
Posts: 8785
Joined: Wed May 22, 2013 3:17 am
Delivery Date: 31 May 2013
Location: Upstate New York, US

Re: Near Turtle to cells balanced: 20.8 kW with 2015 Leaf with 24 kW battery: Low kW? As expected? Battery losing capaci

Thu Mar 01, 2018 7:48 pm

That surprises me that there might be only 1 or 2 or 3 miles remaining after "Turtle Mode" reached, so I will be more careful in the future. I REALLY don't want to push the Leaf.


Turtle mode is meant to give you enough time to park the car safely. It's the VLBW that should be taken as "I have just a few miles left." The goal for everyone should be to never see Turtle mode.
Scarlet Ember 2018 Leaf SL W/ Pro Pilot
2009 Vectrix VX-1 W/18 Leaf modules, & 3 EZIP E-bicycles.
PLEASE don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

BuckMkII
Posts: 195
Joined: Sat May 06, 2017 8:04 am
Location: Seattle

Re: Near Turtle to cells balanced: 20.8 kW with 2015 Leaf with 24 kW battery: Low kW? As expected? Battery losing capaci

Tue Mar 06, 2018 7:50 am

A question kinda related to this subject: I don't have a fancy EVSE, just the OEM, and do >90% of my charging on the dumb L2 at work. If I leave LeafSpy connected during charging (which I've never tried doing), will it measure the actual energy added to the battery, or is it always just estimating kWh from some other parameter?
2013 SV no QC, built 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
bar 12 lost 8/21/17
on 2/2/18: AHr = 56.1; SOH = 85.7%; Hx = 81.5; ODO = 44,444

BuckMkII
Posts: 195
Joined: Sat May 06, 2017 8:04 am
Location: Seattle

Re: Near Turtle to cells balanced: 20.8 kW with 2015 Leaf with 24 kW battery: Low kW? As expected? Battery losing capaci

Tue Mar 06, 2018 7:57 am

ldallan wrote:Am I the only one who is paranoid enough to worry about potential hacking with Leaf-Spy software that can apparently "Write" values to the car, such as windshield wipers, etc. I would prefer a less powerful Leaf-Spy that was "Read-Only".

That does seem kinda paranoid. Why would someone hack your phone then waste time dinking around with your car settings? Surely they could find something more valuable to play with?

I do worry about the future of car-hacking, but not until those infernal Skynet-spawned self-driving cars become common. It seems inevitable that they will not be secure enough to prevent some hostile actor from taking over a large number of cars and having them all suddenly turn sharply left into oncoming traffic (or the Jersey barrier) at the same time one morning.
2013 SV no QC, built 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
bar 12 lost 8/21/17
on 2/2/18: AHr = 56.1; SOH = 85.7%; Hx = 81.5; ODO = 44,444

booper
Posts: 48
Joined: Sat Jun 29, 2013 12:33 am
Delivery Date: 29 Jun 2013
Location: Seattle, WA

Re: Near Turtle to cells balanced: 20.8 kW with 2015 Leaf with 24 kW battery: Low kW? As expected? Battery losing capaci

Wed Mar 07, 2018 2:04 pm

finman100 wrote:seems about right. My 2014 SV with 43,000 miles is down a bar and I regularly get 18.5 kWh from empty to full and balanced.
empty is when there are dashes on the dash GOM (1 kWh left in the "tank" per Leafspy).

full is 100% charge and Leafspy showing 18.5 kWh.

Hopefully that helps.


I was just wondering about this myself. Looks like the most I've I've gotten into my 2015 SV from a ChargePoint station was 21.155kWh, but that was about a year ago. I'm pretty sure I was well past VLBW for that charge, but I've never taken it to Turtle. Still have all 12 bars.

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