Can you determine if your battery is normal by charge times?

[ELROY]

16 amp EVSE Upgrade
241 Volt Wall Outlet Voltage

16 amp x 241v=3856 watts
(85% efficiency): 3277 watts charging x 4.35hrs= 14254.95 watts (14.25 kWh)
At this rate, even charged to 100%, I am thinking at the most 2.8kWh additional could have been stored. Especially considering how fast my car goes from 12bars to 10 bars, often within 7 miles of driving. So, perhaps 17.05kWh (14.25+2.8) battery capacity from 100% down to LBW. Considering I should have around 21kWh usable, I am wondering if my battery capacity might be compromised.
I almost always charge to 80%. I did charge to 100% for about 2 wks straight to make sure the battery packs we balanced as best possible. Battery temp is almost always steady at 5-6 temp bars.
Never Quick Charged.
Mild temps…average of 50-70F.
So for those of you getting around 4-5mi/kWh economy, are you only getting around 50-60 miles of travel on a 80% charge till LBW?

 

[ELROY]

Also wondering if the ESVE might be drawing a little more than 16amps. Perhaps 16.5amps?
The reason why is on my electrical consumption, my regular baseline during super-off-peak times seems to be around 500 watts or so. When charging it seems to be at least 4500 watts. So I am thinking the car is drawing around 16.59amps (4000 watts) at the wall?

I know the Edison graph is unscientific, so I will hook up my current meter soon as I can.

Even at 4000 watts at the wall, I am still only looking at about 14790 watts to the battery in 4.35hrs of charge time. Seem ridiculous to be using only 14.79 kWh out of a 24kWh rated battery, doesn't it? (even at 80% charge)

 

[planet4ever]

• The LEAF protects somewhere around 10% of the total capacity, since charging a lithium battery to a true 100% or discharging it to a true 0% is a recipe for a very short life.
• A bit past LBW to "80%" is actually about 70% of usable capacity. (Phil tells us that is 80% of total capacity, so 84%-85% of usable capacity, and Tony tells us that LBW is at about 17% of usable capacity.)
• Tony calculates that the battery loses about 1% capacity for every 4°F below 70°F. Since you said 50° to 70°, let's say your battery was at 60°F, so had 2.5% reduced capacity.

24 kWh * 90% * 70% * 97.5% = 14.74 kWh

Does 14.79 kWh still look ridiculous to you?

(I haven't gone into any of the other problems with your methodology, such as that the charging rate is not constant, the battery temperature is not constant, even the voltage at the wall will fluctuate and may decrease as wires heat up.)

Ray

 

[midelectric]

So has anyone been able to turn on the battery heater manually, say while charging, to retain capacity at lower temps?

 

[TonyWilliams]

So has anyone been able to turn on the battery heater manually, say while charging, to retain capacity at lower temps?

Nobody that I'm aware of.

 

[mark1313]

As the battery wears out,it will take less time to charge it...It takes me 3 hours 10 minutes to fully charge my Leaf now @ around -30% capacity..It took around 4.5 hours to fully charge the car when it was new...

 

[chrisie75]

So has anyone been able to turn on the battery heater manually, say while charging, to retain capacity at lower temps?

It won't help. As I understand, as long as you drive in cold weather, it won't matter much weather you charge at higher temperature or not-at least in the scale of leaf's 24kwh capacity. You probably do not need to bother that.

 

[Den]

When charging it seems to be at least 4500 watts. So I am thinking the car is drawing around 16.59amps (4000 watts) at the wall?

Leafs charger is max 3,6kW - so it can't draw more that this (3,6kW).

On Monday I charged from 2 bars (not full) till 80% through power-meter. It showed 15kWh. Temp. 0C (4 bars).

 

[gbarry42]

I track charging stats, and one thing I can say is that the power supplied is within a few watts of 3.75kW. This does not change from day to day. I don't know the exact line voltage but it seems pretty reasonable that it's the same each night.

The recharge energy figures always seem too low, until you remember to subtract off some for 80% vs 100%, some for the fact that you didn't really get to zero bars, some for the energy they "hide" below zero bars, some for the untouchable "reserve" at max and min charge, and maybe one or two other factors I'm forgetting. Then the number becomes believable.

 

[ELROY]

Added a couple more charge periods to my chart:

 

[TonyWilliams]

So has anyone been able to turn on the battery heater manually, say while charging, to retain capacity at lower temps?

It won't help. As I understand, as long as you drive in cold weather, it won't matter much weather you charge at higher temperature or not-at least in the scale of leaf's 24kwh capacity. You probably do not need to bother that.

No true at all. The battery ITSELF will lose capacity with cold temperatures.

If you had the battery at -10F / -20C degrees, the battery would lose about 20% of its capacity. Hence, simply heating it up will increase its capacity.

It's actually a bit silly that the LEAF doesn't heat the battery for winter time, particularly when plugged in. Virtually every other electric car does.

 

[ELROY]

Did some more charge time logging. Kind of confirms my thoughts about an 80% charge only being good for about 40-50 miles in normal driving. (Without having to get into VLBW, etc). Yes, I could feather foot it and get further. At this point, I sure wish the car would achieve 80 miles in everyday 80% charging mode. And when technology allows (and battery prices come down), I still hope my next BEV is good for 100 miles on a regular charge.

Is this what most people are getting on a 80% drive in normal driving. 40-50 miles??
And is your charge time also in the 3.5-4.5 charge time for that same range?

 

[vegastar]

In the Winter I get 40-50miles from 80% to LBW. In the summer it's more like 50-60miles.

 

[ELROY]

In the Winter I get 40-50miles from 80% to LBW. In the summer it's more like 50-60miles.

Thanks, good to know your results.
Temps here right now are in the 50-65F range.

 

[DaveEV]

45-50 miles from 80% to LBW is typical for me in the low-mid 4.0 mi/kWh range. To do significantly better I need to get around 5.0 mi/kWh which doesn't happen often.

 

[ELROY]

45-50 miles from 80% to LBW is typical for me in the low-mid 4.0 mi/kWh range. To do significantly better I need to get around 5.0 mi/kWh which doesn't happen often.

Its amazing how it goes from Nissan's stated 100 miles range, to the EPA's 73 miles, and then down to real owner's practical 40-50miles on 80% charge to LBW. My car is only about 4 months old. Throw in some battery degradation, and this could really be an issue for many people. I hope the come out with some revolutionary battery technology soon!

 

[Luft]

Remember that the Nissan estimate was based on a battery charged to 100% and the car driven at very low speeds. The EPA's estimate is more realistic but must have been done in warmer temperatures.

If you don't have Tony's range charts yet, I would highly recommend them. They seem very accurate to me.

Let's do some calculating based on your data, Tony's charts and your temperature assumptions: I'm assuming a temperature of 40F and your battery is new.

First let's adjust your battery capacity based on temperature:

70F - 40F = 30F If we lose 1% for every 4F that's 7.5% We have about 21 usable KWh at 70F when fully charged so you will lose 1.58 KWh to the cold. That leaves you with 19.43 if you charge to 100%.

If you charge to 80% of that you have 15.54 KWh.

Let's look at the line where you went 37.1 miles (I'll round off to 37) and got 3.8 miles per KWh: 37miles / 3.8 m/KWh = 9.74 KWh used. that leaves (15.54 - 9.74) or 5.8 KWh remaining.

5.8 KWh / 21 KWh = 28%

Now look at Tony's chart and run your finger up the left hand side until you find where that percentage falls and read the number of bars that should be remaining. I read it as 2 bars. That's EXACTLY what you recorded.

It looks to me like your battery pack is fine. Fear not, warmer weather will bring you much joy.

45-50 miles from 80% to LBW is typical for me in the low-mid 4.0 mi/kWh range. To do significantly better I need to get around 5.0 mi/kWh which doesn't happen often.

Its amazing how it goes from Nissan's stated 100 miles range, to the EPA's 73 miles, and then down to real owner's practical 40-50miles on 80% charge to LBW. My car is only about 4 months old. Throw in some battery degradation, and this could really be an issue for many people. I hope the come out with some revolutionary battery technology soon!

 

[davewill]

45-50 miles from 80% to LBW is typical for me in the low-mid 4.0 mi/kWh range. To do significantly better I need to get around 5.0 mi/kWh which doesn't happen often.

Its amazing how it goes from Nissan's stated 100 miles range, to the EPA's 73 miles, and then down to real owner's practical 40-50miles on 80% charge to LBW. My car is only about 4 months old. Throw in some battery degradation, and this could really be an issue for many people. I hope the come out with some revolutionary battery technology soon!

If you're worried about range, why would you only charge to 80%? Makes no sense to me.