lorenfb
Posts: 1387
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: LeafDD - Dash Display for Leaf

Sat Nov 11, 2017 4:40 pm

lorenfb wrote:
jjeff wrote:^^^ interesting, I haven't noticed that. How hard and for how long do you have to push on the accelerator to get that number to appear? Also how long does it display after it appears? I take it a higher internal resistance is worse than a lower one, what is a typical number and what number might mean a battery is getting weaker? My '12 is down to 9 bars and only has a capacity of 47 and Hx around 51, I'd imagine it's internal resistance would be quite a bit higher than a Leaf with a good battery.


1. It takes about 10 seconds for it to sample the data.
2. It stays as long as you stay on that screen. Once the screen is changed, It will not be shown the next time that screen is displayed.
3. Yes, just like a lead-acid battery, a higher the resistance indicates aging and more heat developing as a function of load or charging.
4. The output resistance does change over time. I'll post my data taken over the last 3 years later today.


Here are the battery resistance data:

11/20/14 -13,700 miles, 76 mohms per LeafDD, 20 Deg, 73% SOC
11/27 -13,800 miles, 67 mohms per LeafDD, 25 deg, 63% SOC
11/30 - 13,900 miles, 56 mohms per LeafDD, 27 deg, 71% SOC
12/2 - 14.100 miles, 55 mohms per LeafDD, 28 deg, 67% SOC
12/16 - 14,500 miles, 89 mohms per LeafDD, 15 deg, 93% SOC
12/27/14 - 14,800 miles, 103 mohms per LeafDD, 11 deg, 24% SOC
3/10/15 - 17,400 miles, 60 mohms per LeafDD, 30 deg, 73% SOC
3/14 - 17, 550 miles, 56 mohms per LeafDD, 32 deg, 47% SOC
4/14 - 19,100 miles, 59 mohms per LeafDD, 25 deg. 38% SOC
5/4 - 19,989 miles, 64 mohms per LeafDD, 24 deg. 48% SOC
5/15 - 20,400 miles, 73 mohms per LeafDD, 20 deg. 41% SOC
5/22 - 20,700 miles, 58 mohms per LeafDD, 28 deg. 50% SOC
12/10/15 - 28,000 miles, 90 mohms per LeafDD, 19 deg. 92% SOC
4/5/16 - 32,000 miles, 74 mohms per LeafDD, 24 deg, 55% SOC
5/16 - 33,700 miles,89 mohms per LeafDD, 22 deg, 47% SOC
5/16 - 33.700 miles, 58 mohms per LeafDD, 31 deg, 76% SOC
10/5 - 39,300 miles, 100 mohms per LeafDD, 22 deg, 50% SOC
10/6 - 39,400 miles, 61 mohms per LeafDD, 30 deg, 51% SOC
10/7 - 39,500 miles, 80 mohms per LeafDD, 25 deg, 56% SOC
10/15 - 40,000 miles, 71 mohms per LeafDD, 27 deg, 45% SOC
10/30 - 41,000 miles, 74 mohms per LeafDD, 23 deg, 66% SOC
12/26/16 - 43,000 miles, 110 mohms per LeafDD, 13 deg, 77% SOC
6/10/17 - 49,600 miles, 89 mohms per LeafDD, 19 deg, 70% SOC
7/1/17 - 51,000 miles, 62 mohms per LeafDD, 33 deg, 44% SOC
8/15/17 - 53,400 miles, 61 mohms per LeafDD, 35 deg, 57% SOC

Once these are graphed (someday), a family of curves will result with;
Y axis being resistance, X axis being temperature, with each stacked curve being an aging point in time with a negative
temperature slope.

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Stanton
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Re: LeafDD - Dash Display for Leaf

Sun Nov 12, 2017 7:46 am

I didn't expect/know that the battery resistance data would vary so widely; I thought it would simply rise with age/degradation?
I assume those temps are Fahrenheit (Celsius would be too hot)?
2011 Blue Ocean SV w/floor mats & window tint
12v LiFePO4 battery & FIAMM 74100 horns
Wet Okole seat covers (front)
Tor's low-power heater mod
2013 sun visor
3G modem upgrade
L2 EVSE Upgrade
Battery Pack replaced (Rev E) @51 months and 41k miles

lorenfb
Posts: 1387
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: LeafDD - Dash Display for Leaf

Sun Nov 12, 2017 9:40 am

Stanton wrote:I didn't expect/know that the battery resistance data would vary so widely; I thought it would simply rise with age/degradation?
I assume those temps are Fahrenheit (Celsius would be too hot)?


Those are degrees centigrade. The hottest was 35C (95F).

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