IS THIS NORMAL FOR A LEAF?

[TonyWilliams]

... this is done by Coulomb counting into and out of the battery using a measuring device which is not very precise. But when you power down the computer can get a more accurate measure of the battery's state (using no-load voltage?). So is it not surprising that the charge reported at power up would differ from prior to power down.

Note: I'm not an EE, so I may well be misrepresenting this.

Ray

Yes, things are adjusted with Open Circuit Voltage. This car, for practical purposes, can be considered at VLB (8.6%).

He drove 80.3 / 4.3 = 18.6 kWh burned, with 1.8kWh left (8.6% of 21 kWh)

20.4kWh versus his calculated (using the recharge time?) of 20.2 kWh.

Battery is fine.

NOTE: As always, we don't need GuessOmeter data, but we do need battery temperature, miles/kWh, miles driven and "landmark" event (LBW, VLB, Turtle).

 

[ELROY]

So I changed to the tme of use electrical vehcle plan.
Essentially between 12am and 6am there is a super off-peak rate of .17 cents/kwH.

Using some numbers I have read about battery capacity, I came up with the following:

Energy Cost Calculations:
24000 watt-hours Battery Pack.
Full Charge Usable: 94%: 21866 watt-hours (80 miles approx)
80% Charge Setting: 80%: 18340 watt-hours (64 miles approx)

240V Charging Upgrade
Charger: 16A x 240v= 3840 watts, actual 3264 watts charge (85% efficiency)
.17 cents kwH Edison Super off Peak rate
.65cents/hr to charge. x 5.6hrs = $3.64 (64 Miles approx. 80% battery saving charge)
.65cents/hr to charge x 6.6hrs= $4.29 (80 Miles approx. Full charge)

And if I were to get a seperate meter installed for my 240V outlet:
.12 cents kwH Edison Separate meter rate (winter off peak)
.46cents/hr to charge x 5.6hrs= $2.58 for 64 miles
.46cents/hr to charge x 6.6hrs= $3.03 for 80 miles

So in the 39000 miles of total lease allowed mileage, this would mean 487.50 charge cycles (at 80 miles each).
If I were only saving $1.26 per charge with the seperate meter, I would only save $614.25 over the term of the 39000 mile lease.
Thus it simply does not justify spending over $1000 to get the seperate meter.
I do however need to see what the regular other household electric bill savings would be by not always being on the highest tier charge that the EV pushes me into automatically.

120V comparison:
Charger:12A x 120v= 1440 watts, actual 1080 watts charge (75% efficiency)
.17 cents kwH Edison Super Off Peak Rate
.244 cents/hr to charge x 16.98hrs= $4.14 (64 miles approx. 80% battery saving charge)
.244 cent/hr to charge x 20.20hrs= $4.92 (80 miles approx.. Full Charge)

 

[ELROY]

As far as range and miles/kWh are concerned. How does using the climate control when parked calculate into the scheme of things. I noticed the other day when using the heater while parked, it didn't seem to lower my m/kWh efficency or range as time went by. Is this energy usage when parked tracked by the computer still? Do I have to stop and restart the car for it evaluate how much energy has diminished from the battery pack? Or perhaps after the next 30 seconds of driving, all will be updated properly? Both range and efficiency readings?

Also, trying to find out the best way to maximize efficiency. I know driving slow, and reducing rate of acceleration are key, but what about doing other things to reduce power usage. I find myself driving in "D" at times, the coasting in neutral where applicable. And then when coming to a stop, switching back through D and then to"Eco" in order to maximize my regeneration yield. Seems kind of like a pain. I mean going from D to Neutral is easy enough, but I don't feel like I am getting maximum regeneration without going to Eco. Does ECO indeed regenerate more in a stop than "D"? It does seem to generate more of the regen bubbles soon as you switch over to ECO. However, is it no better than just stepping on the brakes a little harder in "D" and achieving the same amount of regen bubbles? Don't really know why they would make max accel capabilties in "D" exclusive to having maximum regen without having to switch the shifter back and forth everytime you want to maximize the regeneration capabilities.

 

[planet4ever]

As far as range and miles/kWh are concerned. How does using the climate control when parked calculate into the scheme of things. I noticed the other day when using the heater while parked, it didn't seem to lower my m/kWh efficency or range as time went by. Is this energy usage when parked tracked by the computer still? Do I have to stop and restart the car for it evaluate how much energy has diminished from the battery pack? Or perhaps after the next 30 seconds of driving, all will be updated properly? Both range and efficiency readings?

I wouldn't know anything about "range", because I've learned not to trust the GuessOMeter, and I pay no attention to it. As for the dash m/kWh readout, I reset that every time I charge, and if I park for a while with the heat on it seems like I end up with a very low reading at the end of the day. I don't have any scientifically verifiable data to prove that, though, and I haven't watched to see if the number is dropping while parked.

Does ECO indeed regenerate more in a stop than "D"? It does seem to generate more of the regen bubbles soon as you switch over to ECO. However, is it no better than just stepping on the brakes a little harder in "D" and achieving the same amount of regen bubbles?

To tell you the truth I think it is indeed possible to get just as much regen in D as in ECO, but when driving in D:

• For maxiimum efficiency you have to be sure your touch on the brake pedal is light enough that you are not activating the friction brakes until you have nearly stopped.
• In heavy traffic conditions you end up moving your foot from one pedal to the other more frequently.

On the first point, I think someone claimed a while back that they could tell when the friction brake was activated based on the dots above the tree being generated in the eyebrow, but I don't remember much about that. I also believe someone found a CAN message indicating brake pad pressure, and built a monitor that would indicate that by a beep rate. That sounded good, but I can't seem to find it now.

The second point has both good and bad aspects. You can presumably react faster using one-pedal (ECO) driving, but your brake lights don't go on until you use the brake pedal, so the person behind you can react faster if you use two-pedal (D) driving.

Ray

 

[dgpcolorado]

...Also, trying to find out the best way to maximize efficiency. I know driving slow, and reducing rate of acceleration are key, but what about doing other things to reduce power usage. I find myself driving in "D" at times, the coasting in neutral where applicable. And then when coming to a stop, switching back through D and then to"Eco" in order to maximize my regeneration yield. Seems kind of like a pain. I mean going from D to Neutral is easy enough, but I don't feel like I am getting maximum regeneration without going to Eco. Does ECO indeed regenerate more in a stop than "D"? It does seem to generate more of the regen bubbles soon as you switch over to ECO. However, is it no better than just stepping on the brakes a little harder in "D" and achieving the same amount of regen bubbles? Don't really know why they would make max accel capabilties in "D" exclusive to having maximum regen without having to switch the shifter back and forth everytime you want to maximize the regeneration capabilities.

If you don't do it already, put up the energy screen on the console and it will give better information about power used/regenerated than the dots and bubbles. It also can be used to hold the car in "neutral" using the "A" pedal, without shifting to neutral, which is useful for short stretches of coasting.

After coasting I use D and Eco to tweak my regen when slowing or stopping: I'll start with D because it gives a bit of regen—and turns on regen for the "B" pedal in case of a quick stop—and then shift to Eco to get quickly down to the speed I need to make my turn or to stop. Besides driving efficiently, it is something of a game for me. Since traffic is rare where I live concerns about brake lights are not an issue, but that is something to consider when driving in heavy traffic: one brief lapse by the driver behind and you could end up hit from the rear. In that case using the brake pedal to slow would be best—safety first!

 

[ELROY]

...Also, trying to find out the best way to maximize efficiency. I know driving slow, and reducing rate of acceleration are key, but what about doing other things to reduce power usage. I find myself driving in "D" at times, the coasting in neutral where applicable. And then when coming to a stop, switching back through D and then to"Eco" in order to maximize my regeneration yield. Seems kind of like a pain. I mean going from D to Neutral is easy enough, but I don't feel like I am getting maximum regeneration without going to Eco. Does ECO indeed regenerate more in a stop than "D"? It does seem to generate more of the regen bubbles soon as you switch over to ECO. However, is it no better than just stepping on the brakes a little harder in "D" and achieving the same amount of regen bubbles? Don't really know why they would make max accel capabilties in "D" exclusive to having maximum regen without having to switch the shifter back and forth everytime you want to maximize the regeneration capabilities.

If you don't do it already, put up the energy screen on the console and it will give better information about power used/regenerated than the dots and bubbles. It also can be used to hold the car in "neutral" using the "A" pedal, without shifting to neutral, which is useful for short stretches of coasting.

After coasting I use D and Eco to tweak my regen when slowing or stopping: I'll start with D because it gives a bit of regen—and turns on regen for the "B" pedal in case of a quick stop—and then shift to Eco to get quickly down to the speed I need to make my turn or to stop. Besides driving efficiently, it is something of a game for me. Since traffic is rare where I live concerns about brake lights are not an issue, but that is something to consider when driving in heavy traffic: one brief lapse by the driver behind and you could end up hit from the rear. In that case using the brake pedal to slow would be best—safety first!

I do usually have the energy screen on while I drive. So when the line is neither +/- (disappeared) it would be similar to neutral, but I still dont think that gives you the total freewheeling type coasting as though you are in neutral. I think with your foot on the same position, if it starts to coast faster down hill/etc, it will start going into regen/slowing you down. "N" offers no regen, but no resistance either, so you can really coast a long time on some slopes.

 

[LEAFer]

...
...
To tell you the truth I think it is indeed possible to get just as much regen in D as in ECO, but when driving in D:

• For maxiimum efficiency you have to be sure your touch on the brake pedal is light enough that you are not activating the friction brakes until you have nearly stopped.

...
...
Ray

From our December 1 Sacramento meetup at Nissan's WestSac facility I remember a Nissan Engineer saying touching the brake pedal even lightly "engages" the friction brakes to "prime the pump" (so to speak). In other words, the system is anticipating that you may want to come to a quick stop. Yes, there is only a small amount of actual effective "friction" deceleration with light brake pedal pressure while the regen does most of the "work" ... but the brake pads are "engaged".

 

[dhanson865]

So elroy, did you decide your heater works after all?

 

[ELROY]

So elroy, did you decide your heater works after all?

It takes a long time..and sometimes only luke warm. The kW meter does show it going anywhere from 1.5 to about 4.5 on the climate control. When its at 4.5kw, it is definitely blowing warm. Not sure about the reason for the delay...its like it has to warm up a bucket of water before it starts blowing warm air. And yes...i have the temp set at max.

As far as the friction brakes...i just brake as hard as i can to just get the maximum regen bubbles. If you lightly brake you get less bubbles. So perhaps i am looking at this wrong?

 

[RegGuheert]

It takes a long time..and sometimes only luke warm. The kW meter does show it going anywhere from 1.5 to about 4.5 on the climate control. When its at 4.5it definitely is blowing warm.

My observation is that you are limited to about 2kW in "ECO" and about 4.5kW in "D". Defrost seems to not have the same limitations, perhaps because it is considered safety equipment.

Not sure about the delay...its like it has to warm up a bucket of water before it starts blowing warm air. And yes...i have the temp set at max.

I think that's exactly what it has to do. The delay is annoying. This make the recent Carwings issues all the more frustrating.

 

[dgpcolorado]

I do usually have the energy screen on while I drive. So when the line is neither +/- (disappeared) it would be similar to neutral, but I still dont think that gives you the total freewheeling type coasting as though you are in neutral. I think with your foot on the same position, if it starts to coast faster down hill/etc, it will start going into regen/slowing you down. "N" offers no regen, but no resistance either, so you can really coast a long time on some slopes.

Not true when in Eco: you can hold the same pedal position and it will stay in virtual "neutral" despite going up and down hills—try it! I do it all the time, since hills are a fact of life here. One advantage of "Eco-neutral" for short stretches of coasting is that when you back off the A pedal you get instant slowing due to regen. If you are in real neutral and you brake it will all be friction braking, which is kind of a nasty surprise when trying to hypermile. (Of course, one learns to shift back to D or Eco before braking rather than make that mistake again.)

 

[Ingineer]

Charging Questions:
I have been reading many threads on the charging options, and here are my questions I couldn’t find answers to:

a) Is it true the Level 2 chargers are more efficient than the trickle charger? 85% vs 75% or so? If so, what technically makes them more efficient?

There is a fixed overhead of 200-400 watts, so if you are charging on Level 1 (120v 12A), that means there is 1.4kW being used from the wall, but only about 1.1kW is making into the battery, this is roughly adding about a mile of range every 15 minutes. (assuming an average of 3.5 miles per kWh) This L1 charge will take about 21 hours for a fully depleted pack. If you charge on full L2 (240v 16A), you are pulling 3.8kW from the wall, and almost 3.4kW is making it into your pack, or almost a mile every 5 minutes. This also means about 7 hours charge time, so it's significantly more efficient and about 3 times faster.

I have an upgraded charging system in my Leaf, so I charge at about 6.7kW into the battery, so that's adding about 2 miles range every 5 minutes and I'm done in well under 4 hours.

-Phil

 

[ELROY]

Charging Questions:
I have been reading many threads on the charging options, and here are my questions I couldn’t find answers to:

a) Is it true the Level 2 chargers are more efficient than the trickle charger? 85% vs 75% or so? If so, what technically makes them more efficient?

There is a fixed overhead of 200-400 watts, so if you are charging on Level 1 (120v 12A), that means there is 1.4kW being used from the wall, but only about 1.1kW is making into the battery, this is roughly adding about a mile of range every 15 minutes. (assuming an average of 3.5 miles per kWh) This L1 charge will take about 21 hours for a fully depleted pack. If you charge on full L2 (240v 16A), you are pulling 3.8kW from the wall, and almost 3.4kW is making it into your pack, or almost a mile every 5 minutes. This also means about 7 hours charge time, so it's significantly more efficient and about 3 times faster.

I have an upgraded charging system in my Leaf, so I charge at about 6.7kW into the battery, so that's adding about 2 miles range every 5 minutes and I'm done in well under 4 hours.

-Phil

The EVSE upgrade is the best thing I have found for the LEAF so far. With my super off peak time of only 6 hours (12am-6am), over half of my charging time was always spilling into the other higher rate hours. So .27cents/kWh instead of .17cents/kWh. So now with the upgrade, my charging needs easily fit within that 6hr period, significantly lowering my electrical bill.

With a 39mos/39000 mile lease, it still doesn't make sense to invest in the seperate meter hookup for the cheapest electrical rate of around .12cents/kWh.

Basically at the .17 cents/kWh rate (and with 3.8kw charging) it runs about .65cents/hr to charge.
With a SCE seperate meter, at .12 cents/kWh rate it would run about .46cents/hr to charge.

So around a 6hr charge will give me approx 50 miles (avg)
This same charge at .65cents/hr will run about $3.90
This same charge at .46cents/hr will run about $2.76

So at my lease allowed 1000miles/month, this would be about 20 charge cycles per month.
or $78/month (.17 cents kWh rate)
or $55/month (.12 cents/kWh rate)

A difference of $23 month between the 2 rates.
$23/month x 39 month lease= $897

So to pay an electrician over $1000 to install and get a city permit for a seperate electrical meter just doesn't pay off financially.

Here is a sample of my driving down to the low battery warning today from 100% charge.
Mostly city. Only achieved a little over 50 miles. Dash readout states it will take about 7hrs to charge (I am figuring about 6 hrs though). My economy for the session was 3.0 miles/kWhr.

Now I know I have achieved 80 miles of driving on the same amount of charge, driving very gingerly with mostly highway driving. But this 50 miles is more realistically indicative of my everyday driving to work. With $3.90 being the equivalent of a gallon of gas, and yet only getting about 50 miles out of it in the LEAF, this is pretty close to the cost to drive a Prius on a gallon of gas. So good, but not spectacular. Or course when hypermiling and getting 80 miles on the same $3.90, it probably is above what a Prius can achieve.

So this brings me to my next question. How many people actually avoid charging to 100%? With 50 miles of range, its kind of hard to limit myself to an even shorter distance with 80% charging.

Also, with a 23hr charge time (120v), and 3.0 miles/kWh economy and - - - range showing, what kind of remaining range could I expect to achieve till the turtle mode?

Also interesting to note that I was only putting about 750 miles/month on the 335d, and have put almost double that mileage on the LEAF in one month! It will be 2 months old on DEC 27th, and I almost have 2000 miles on it.

 

[DaveEV]

Thoughts: 3.0 mi/kWh is very low for most LEAF owners. This must have happened either on the freeway at 75 mph with the heater on. See range chart.

When you see --- on the GOM, that is the 2nd low battery warning called very-low-battery-warning (VLBW). Continuing at 3.0 mi/kWh you might have another 3 miles of range left. See range chart. Strange that you still had 1 bar showing - usually that bar goes away when you get VLBW.

If you need to charge to 100% to give yourself sufficient range, you should plan on having it finish charging as close to your departure time to minimize the effects of charging to 100%. In cold temps (< 60F) this isn't as much of an issue as hot temps (> 80F).

Most here would recommend slowing down and driving more efficiently. You should be able to get close to 4.0 mi/kWh pretty easily which would give you 15 more miles range compared to driving at 3.0 mi/kWh.

50 miles at 80 mph takes 37.5 minutes.
50 miles at 65 mph takes 46 minutes.
Not exactly a huge difference, but if you come up 10 miles short it's going to take a lot longer than 10 minutes to get enough charge to get home unless you happen to run out next to a QC station.

 

[ELROY]

With the exception of about 10 miles of fwy driving...this was all city driving. Its pretty much becoming the norm for me to get better range on the fwy than my daily city driving. I can drive 52 miles from Ventura County to Los Angeles at 60mph+ and still have 2 bars left. In fact , my 80miles trips were 80% freeway. Temps are 50-60F right now. I normally drive it within 2 hrs of charging it to 100%. The most I have ever seen on the battery temp was 6 bars.
I rarely use the heater except for some emergency defrosting. The reason for the one bar is I still had about 5 miles of range...but turned off the power and then restarted again to give the system time to re-evaluate the battery level. This always happen to me when the battery is low. Restarting the system will show a lower range. What is the more accurate method?

Thoughts: 3.0 mi/kWh is very low for most LEAF owners. This must have happened either on the freeway at 75 mph with the heater on. See range chart.

When you see --- on the GOM, that is the 2nd low battery warning called very-low-battery-warning (VLBW). Continuing at 3.0 mi/kWh you might have another 3 miles of range left. See range chart. Strange that you still had 1 bar showing - usually that bar goes away when you get VLBW.

If you need to charge to 100% to give yourself sufficient range, you should plan on having it finish charging as close to your departure time to minimize the effects of charging to 100%. In cold temps (< 60F) this isn't as much of an issue as hot temps (> 80F).

Most here would recommend slowing down and driving more efficiently. You should be able to get close to 4.0 mi/kWh pretty easily which would give you 15 more miles range compared to driving at 3.0 mi/kWh.



50 miles at 80 mph takes 37.5 minutes.
50 miles at 65 mph takes 46 minutes.
Not exactly a huge difference, but if you come up 10 miles short it's going to take a lot longer than 10 minutes to get enough charge to get home unless you happen to run out next to a QC station.

 

[dgpcolorado]

3.0 miles/kWh is pretty low in a mild climate like LA. This may sound silly, but have you checked your tire pressure lately? Try 40 psi and you might do better than if you are at 36 psi or lower. The rest of driving efficiently just comes from easy-does-it hypermiling techniques much discussed in other threads.

Given your rather high cost of electricity your comparison to the Prius gas cost seems about right. But was the car you are replacing with a LEAF really a Prius? Even if it was, the plain fact is that the Prius is an oil burner and the LEAF isn't, which is a major consideration for a lot of us.

...As far as the friction brakes...i just brake as hard as i can to just get the maximum regen bubbles. If you lightly brake you get less bubbles. So perhaps i am looking at this wrong?

Yes, you have this quite backwards. If you must use the brake pedal rather than drive in Eco and mostly use the A pedal, applying it gently, or firmly for a moment then backing off to use mostly regen, will give better results. In general it is more efficient to drive as if you have no brakes: accelerate and decelerate gradually and gently, anticipate stops so that you start slowing before you get to the red light or stop sign, and so forth. This sort of driving can make an enormous difference in mileage efficiency compared to what most drivers do: stomp on the accelerator to go and stomp on the brakes at the last minute to stop. Back during the gas crises of the '70s the lesson I took to heart was "drive as if you have an egg under the accelerator and you don't want to break it".

 

[dgpcolorado]

...I rarely use the heater except for some emergency defrosting. The reason for the one bar is I still had about 5 miles of range...but turned off the power and then restarted again to give the system time to re-evaluate the battery level. This always happen to me when the battery is low. Restarting the system will show a lower range. What is the more accurate method?

When you turn off the car and then turn it on again the top fuel bar will disappear if it is less than half full. So, if you have 3.4 bars of fuel it will show as four bars while driving until you get to 3.0. But if you turn the car off and back on again it will show three bars because the fourth bar is less than half full. As you have found, it is useful to know this because you can use it to determine whether you are in the top half or bottom half of a fuel bar. It would be nice to have a fuel gauge that had more granularity but unless you get an add-on device like a "Gid-meter" there isn't a simple way to do it.

The 2013 LEAF will, finally, have a % SOC gauge that will be a big improvement over the current display (although some here would prefer an actual measurement of KWh of charge remaining, if that was practical to calculate).

 

[Ingineer]

Yes, in LA you should definitely be able to get better range. I can do 4 miles/kWh even with highway if I try. I have my tires set to 50 PSI all around (I do not recommend you exceed the sidewall). I do have the Climate Control Upgrade that lets me truly shut off the heater, which can be a huge range suck this time of the year.

I can easily do 60 miles on an 80% charge without even trying that hard.

-Phil

 

[ELROY]

Yes, in LA you should definitely be able to get better range. I can do 4 miles/kWh even with highway if I try. I have my tires set to 50 PSI all around (I do not recommend you exceed the sidewall). I do have the Climate Control Upgrade that lets me truly shut off the heater, which can be a huge range suck this time of the year.

I can easily do 60 miles on an 80% charge without even trying that hard.

-Phil

I raised my pressures to 40psi the first day I picked up the car. Going to raise it to 44psi next.
Also I assume that the 7hrs of estimated charge time taking only 6hrs is typical..and not a result of reduced battery capacity?? I am using the 16ampto EVSE upgrade.

 

[Ingineer]

I raised my pressures to 40psi the first day I picked up the car. Going to raise it to 44psi next.
Also I assume that the 7hrs of estimated charge time taking only 6hrs is typical..and not a result of reduced battery capacity?? I am using the 16ampto EVSE upgrade.

I would go to 44psi. Like I said, I'm running 50. (But I don't recommend that!)

If you run the pack down all the way until it cuts off after turtle, it can take almost 7 hours for a full charge on 240v 16a. If you don't run it until it cuts off, then it will be a shorter time. If it's cold, it could take a little longer. You can't go by charge time as a reliable indicator of capacity loss.

-Phil