Well, I tested the Range today...Driving 72 miles each way

I started off the morning driving from San Jose to Monterey. It was 72 miles, and I had 59 on the range. I'd previously seen the mileage being "underrated" so I said I'd go for it.

I made it to a Walgreens with a j1772 with 10 miles remaining on the range! Very surprised to see that I traveled an actual 72 miles with a 49 mile drop in range. Not ideal, but I'll take the conservative outlook.

On the way back, however... After 3 hours, the car charged from 10 miles back up to 55. I hit the road hoping for the same underrated range. I was off by 22 miles, had to stop at a Ford dealer and charge, which pissed off a couple employees. I got back to my destination with 1 mile left on the range.

I wasn't able to fully charge either way, or use the extended range, but wanted to see if you guys had the same funky range estimates and behavior that I experienced today.

Oh, and how slow was the Leviton Ford charger?! It took 1 hour to get 17 miles of range. I'm guessing it was their 32A vs the 60(40A I use) Juicebox I have at home and work.

This is normal for the range estimation EV's to be conservative.
My Smart ED has similar behaviour.
I blogged my experiences going "below zero":
http://mysmartelectricdrive.blogspot.ca/2014/05/running-on-empty-cause-thats-way-i-roll.html

As for the reverse drive using more energy, it may be due to elevation change (downhill on way out, uphill back) or wind direction (at your back on the way out, headwind on way back) or speed (you got cocky on the way back thinking that it didn't matter how carefully you accelerated).

The major reason I'm getting the B Class is the drive from Los Altos to Carmel. 74 miles I think. So would you say, with a fully extended range charge, I'd have no problem getting there? What speed did you drive, and using AC or heat? (Warm day today so probably no heat!)

The Mercedes B-Class ED has the following capacities with a new condition battery at room temperature:

28.0 kWh - normal charge
31.5 kWh - extended charge

The car will consume the power at 3.6 miles per kWh (will show as 3.0 on the dash***), therefore the range is:

28.0 * 3.6 = 100 miles

31.5 * 3.6 = 113 miles


As always, using the cabin heater, cold ambient temperatures, snow, standing moisture on the road, up hills, etc, all reduce range. The battery will degrade over time.


Range is at 65mph (100km ground speed) on dry, hard surface level road with no wind or cabin climate control with new condition battery at 70F, battery capacity is "useable" amount, not advertised amount. Ranges are at maximum available charge and EPA rating is the maximum published.

Other cars:


Nissan
LEAF - 4 miles per kWh (250 wattHours per mile) * 21.3kWh = 85.2 miles / EPA 84


GM / Chevrolet
Spark EV - 5 miles per kWh (200 wattHours per mile) * 19kWh = 95 miles / EPA 82


Mercedes
B-Class ED - 3.6*** miles per kWh (278 wattHours per mile) * 31.5kWh = 113 miles / EPA 104


Toyota
Rav4 EV - 3.4 miles per kWh (295 wattHours per mile) * 41.8kWh = 142 miles / EPA 113

Kia

Soul EV - 4 miles per kWh (250 wattHours per mile) * 27kWh = 108 miles / EPA 93


*** Mercedes consumption meter is calibrated so that 3.6 miles per kWh will show 3.0 on the dash. The correction factor is 83.7%, or 1.2

TonyWilliams said:

Mercedes
B-Class ED - 3.6*** miles per kWh (278 wattHours per mile) * 31.5kWh = 113 miles / EPA 104

*** Mercedes consumption meter is calibrated so that 3.6 miles per kWh will show 3.0 on the dash. The correction factor is 83.7%, or 1.2

Click to expand...

My consumption meter is always between 2 and 2.5 miles per kWh. Which puts me at (2.5miles x 28kWh) 70 miles per kWh. Even with that 1.2 correction factor, I'm only at 84 miles per kWh. Half that of a Rav4. Sucks.

Getting 3.0-3.1 m/kWh last two days with temps in the 50's and 60's. Winter has been 2.2-2.3 m/kWh. Looking forward to getting 3.6 this spring and summer.

This was Saturday:


31.5 kWh charge:

Ferdball said:

TonyWilliams said:

Mercedes
B-Class ED - 3.6*** miles per kWh (278 wattHours per mile) * 31.5kWh = 113 miles / EPA 104

*** Mercedes consumption meter is calibrated so that 3.6 miles per kWh will show 3.0 on the dash. The correction factor is 83.7%, or 1.2

Click to expand...

My consumption meter is always between 2 and 2.5 miles per kWh. Which puts me at (2.5miles x 28kWh) 70 miles per kWh. Even with that 1.2 correction factor, I'm only at 84 miles per kWh. Half that of a Rav4. Sucks.

Click to expand...

My normal day-to-day driving with my RAV4 EVs is 2.7 to 3.0, and 3.4 on the freeway at 65mph.

Obviously, that's in San Diego weather.

TonyWilliams said:

This was Saturday:


31.5 kWh charge:

Click to expand...

What was the MpKwh on this trip?

Also, what does the small gauge on the right cluster, inset in the power meter show? I asked the sales guy and he said it is the battery charge. This make no sense as that is in the left side of the cluster inset into the speedometer.

The dash displayed value would have been about 3.0 miles per kWh (which means 3.6 with a 1.2 correction factor).

31.5 kWh * 3.6 = 113 miles range

Nobody knows what that little gauge on the right really means !!!! (Maybe degradation?)

My understanding of that Ecell gauge was it indicates available power. I can confirm on a non garaged 20 degree day start up it is a few needle widths below max and rises as the battery warms.

I've also seen it drop a needle width or so when then SOC is under 25% which we've only done once. And again on a cold day.

If that gauge also indicates battery degradation in capacity then it would look like full power isn't available as the pack degrades over time. No idea if that is true, Tony does power degrade with time in a measurable way or just the capacity / range?

Ok, it appears to be a power available meter, then.

It makes sense that power would diminish with a cold battery or low SOC%

I wouldn't expect much stored energy degradation, and it doesn't appear there is any indication of that.

The Smart ED has a digital gauge, three "bars", whereas the MB B ED looks to have an analog version of this.

In the Smart ED, this power meter shows available power.

In the Smart ED, there is a kickdown switch on the accelerator pedal, which must be pressed firmly (to full travel) to engage. When the power gauge has all three bars lit, the Smart ED has full power and takes off briskly.

When it gets very cold (-15C for at least a few hours), or when driven below 20% SOC, there are two bars on the gauge, and no matter how hard you hit the accelerator pedal, only 75% of total power is available for acceleration. :-|

When it gets extremely cold (-20C and below for many hours), there have been occasions where I've seen one power bar showing, and in these cases, only 50% (of max) power is available, and it's like driving in a gas powered car again. :-(

My wife has been driving our car for the last couple weeks and we've discovered a few things. After a few trips it seems to default back to the Mercedes calculations of needing to multiple everything by 1.2 to get the EPA ranges.

For example, 80% (or 100% with no range charge added) is 70 miles and 100% (with range charge button pushed) is 80 miles.
If we reset all the trip settings 80% (or 100% with no range charge added) is 84 miles and 100% (with range charge button pushed) is 95 miles. It seems to default back to the conservative Mercedes settings after a trip or two.

Today I took it to work at Tesla and reset everything before the trip and here is what I came up with.

Beginning range on a standard charge (Using 28 kWh of the battery, technically 80% but measured by the car as 100% of the standard charge since no range charge was added after a full reset of everything) Trip was on a Sunday morning and Sunday afternoon so light traffic with pretty easy cruise control conditions.

Start Trip
Battery showing 100% charged
Estimated range 83 miles
Distance traveled 24 miles, 2/3 freeway driving with cruise set on 70mph, interior heat set at 72 degrees, heated seats set on low. 200 foot elevation drop and 400 up during the trip.
Energy consumption 2.9 mpkWh
Estimated range at destination=60 miles
Battery showing 78% left.
Average speed 42 mph, outside average temperature 57 degrees.

Return Trip
Battery showing 78% charged
Estimated range 60 miles
Distance traveled 25 miles, 2/3 freeway with cruise set at 70mph, interior AC set to 72 degrees, 400 foot elevation drop, 200 up during trip.
Energy consumption 3.1 mpkWh
Estimated end range 39 miles
Battery showing 53% left
Average speed 41 mph, outside average temp 76 degrees

Totals
Distance traveled: 49 miles
Battery used: 47%
Estimated range used: 44 miles.
Average energy consumption according to the car: 3mpkWh
Assuming 28 kWh of usable energy the range would be 84 miles on a standard charge and 96 miles if using 32 kWh on a range charge. Maybe a little more if the range charge allows use of 33 or 33.5 kWh.

The 1.2 correction factor is not the range on the GOM... that could be any number (until you reset it).

1.2 is the correction factor for the miles per kWh.

The gauge on the right is the E-Cell gauge. It shows you the ability of the motor to deliver full power. Generally under most conditions it will sit at 100%. However, as you get way down in remaining range it will be less, as the car won't allow you to use full power.

I've been told, but haven't seen, that also if the batteries get extremely hot, that you might see the E-Cell drop in available power.

People get really surprised by the range remaining (GOM) figure, it is very conservative. Usually 12-15 miles too low. The range of the car is how far you drive and the SOC (State of Charge) remaining. Ignore the GOM.....