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Discussion Starter #1
So it finally went below 30 degrees F and I drove 20 miles to work, had 43 miles left, 60%
Did overnight shift, got colder and 43 miles barely got me 19 miles back to home, Heat only used briefly.
I think the battery heater kicks on and runs cont all the way, killing battery power all the way home.

Made is home on reserve with 6 miles range left.

Next project, add second 12v car battery, run those systems from that battery, don't care if it gets run down.
Maybe fool system and put relay in place of heater and pump and tie relay to second battery.

Then at least I can get home.

Drove ICE into work until they look at charger issue there
 

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The large range decline of the Smart ED in cold weather (proportionally larger than other EV's) remains somewhat an enigma. But the battery pack heater cannot be the cause.

According to this site:


The ED3 with the 3.6 kw charger does not have a heater at all. I don't think this is correct and am checking further. Then again, My ED does show "0 hours" on the battery heater in spite of being charged and driven a few times at 0F or below.

At any rate, even if it does have a pack heater, the heater usage cannot be the explanation for the reduced range, because it is only 300 watts or so - and so on a 1 hour trip would use only 300/18000 = 1.7% of the pack capacity.

The interior heater is probably 7000 watts or so and that is a significant drain on the battery pack.
 

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Discussion Starter #3
The cabin heater is 1500 watts, 400 volts. Once temp is warm inside cycles and does not kill range. Also i run it all the way home at 40 deg F and go twice as far as when it is under 30 and no heat on. I do same ride and have kw usage in a spreadsheet collected by my obd2 donggle
 

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My winter range gets down in the mid 40s. I run the heat and don’t try to be conservative because my daily commute is less than 20 miles. I’ve sort of adapted to it. It’s definitely a cure for range anxiety if I ever buy another EV.


Sent from my iPhone using Tapatalk
 

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Dunno why ED didn’t come with heated seats standard??

Gloves, hat, jacket AND BUN WARMERS can provide some relief from range anxiety.

Then too, when the app worked, you could precondition the interior before departure while still on The Grid!
 

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The cabin heater is 1500 watts, 400 volts. Once temp is warm inside cycles and does not kill range. Also i run it all the way home at 40 deg F and go twice as far as when it is under 30 and no heat on. I do same ride and have kw usage in a spreadsheet collected by my obd2 donggle
It is hard to beleive that 1500 watts (hair dryer wattage) would provide enough heat to warm a cold car.
 

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Yep, all EVs suffer in the cold. Depending on which lithium ion chemistry is used the effect can vary along with battery heating techniques.

If you're traveling a distance in the cold with an EV and want a better idea of range in actual conditions, check out abetterrouteplanner.com

I've used it with my Tesla in cold conditions climbing WV mountains and found it to be fairly accurate. You can plug in all kinds of variables for more accuracy (EV make/model, temp, precipitation, battery degradation, weight in car, etc.).

They just released an app as well.

As always, YMMV.
 

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Suppose you go to a dealership to buy a car, and in the discussion you ask about winter driving. The sales person's answer is "Gloves, hat, jacket AND BUN WARMERS can provide some relief from range anxiety." What are the odds you are going to buy that car? Personally, I'm not interested in a car that makes me dress like I'm outdoors to drive in the winter - and I don't think other EVs force that tradeoff. Let's hope Geely does a better job with their version of the EQ replacement than smart did with the current model. YMMV. :)
 

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Suppose you go to a dealership to buy a car, and in the discussion you ask about winter driving. The sales person's answer is "Gloves, hat, jacket AND BUN WARMERS can provide some relief from range anxiety." What are the odds you are going to buy that car? Personally, I'm not interested in a car that makes me dress like I'm outdoors to drive in the winter - and I don't think other EVs force that tradeoff. Let's hope Geely does a better job with their version of the EQ replacement than smart did with the current model. YMMV. :)
Some years ago I had 5 “antique” cars from the mid 1920s to early 1930s. None had heaters. Been there, done that and don’t care to repeat it.
 

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I have the heated seats, but it is not a 453 with the "winter package" ie. extra insulation and heated steering wheel (?). For all of my driving, I've havn't lost anything but seeing range down by a few miles by turning the cabin heat on. Turning the heated seats on do not reduce miles at all though. Best though is preheating the car before disconnection from the wall outlet. BIG BIG help!
 

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I have the heated seats, but it is not a 453 with the "winter package" ie. extra insulation and heated steering wheel (?). For all of my driving, I've havn't lost anything but seeing range down by a few miles by turning the cabin heat on. Turning the heated seats on do not reduce miles at all though. Best though is preheating the car before disconnection from the wall outlet. BIG BIG help!
Yes, heated seats are a far more efficient way to stay warm in an EV and are pretty much mandatory. They use far less power than heating the whole cabin.
 

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I bought a $20 heated seat pad runs off lighter plug, helps a lot. One year even ran it from its own 12v source in my hatch. May just do heated bike gear, but my ice car makes it so easy. But my ice cannot park like a smart

Sent from my SM-N960U using Tapatalk
 

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It was 21F when I started my 13 mile drive to the ferry today. It was about 25 when I finished. I ended up with 83% battery left, according to my OVMS. That 2% higher than normal in chilly weather.

I usually run the defroster a few times during my trip, but I lay off the heat otherwise. Wearing a coat in the car doesn't bother me, since I am about to walk to the ferry then hop on a bicycle.
 

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Discussion Starter #14
Used 5.2kwh to go 20 miles to work. Left house display on fully charged car said 37 miles to empty. Got to work, maybe 27 miles to go empty. Glad i am charged here
 

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A couple important points about lithium batteries and cold weather from my experience messing with my 2-wheel EV's:

1. The actual energy stored by a lithium battery does not change with temperature.

2. But the internal resistance of the cells increases at cold temperatures, and that limits the useful rate (amps) at which you can extract that energy.

3. If you try to draw too many amps at cold temperatures the voltage sags, so you get less power (watts) but especially important, the voltage can sag to a point that it can damage or degrade the life of the cell well before the packs rated capacity us used up. This low safe voltage limit is about 2.7 or 2.8 volts for the most commonly used Li-ion ir Li-polymer cells.

So, I suspect that EV designers "de-rate" the pack capacity to be sure cell voltages don't go too low at the amperages needed for drivability. The SOC goes down faster in cold weather because the battery management software raises the "pseudo" zero-point of the SOC to what is actually a higher SOC.

Smart EDs seem to be especially prone to decline in range in cold weather becasue:

- The current draw relative to the amp-hour capacity (The "C" parameter - where in the case of the smart 1C is 52 amps, 2C is 104 amps etc.) is higher becasue of their small battery.

- This requires a greater cold weather "de-rating" compared to larger battery-EV's.

- It also doesn't help things that the Smart ED has always had poor energy efficiency (miles per kWh or kWh/100 km) compared to other EVs. This has always been an inexplicable feature of the ED, because with it low weight, I would have expected it to be the most efficient EV on the market. Instead, it is one of the worst. My 600 lb bike+rider electric scooter gets about 11 mi/kWh - so low weight definitely should help even with poor aerodynamics.

And this is all before the added drain of using the heater.

We just have to enjoy our ED's/EQ's for what they are. I live in a fairly "compact" city where distances I ned to go are relatively short. But in more sprawling midwest/western US cities the Smarts ED/EQ's definitely have their limitations.
 

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Discussion Starter #16
So latest findings and speculation.

Wen to work, night shift.
Son was using my smart, it was fully charged and he parked it in driveway, cold night in NY last night.
Car was not plugged in at all, seems like battery warming and pump do not run when unplugged, batteries very cold, so may range when plugged in and fully charged was 30 miles 100% charge.

Took car to work tonight, was able to put on charge, fully charged now, even when running heat on it estimates range at 48 miles.

On my way to work batteries did warm up and brought range up, but it does seem like the battery heater and pump take away a lot of power and range from drive system.

I know there is a liquid warming pump and heater because I have seen them for sale, I think I could put a defeat switch and maybe even power them from a different battery/power system.
 

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Discussion Starter #17
A couple important points about lithium batteries and cold weather from my experience messing with my 2-wheel EV's:

1. The actual energy stored by a lithium battery does not change with temperature.

2. But the internal resistance of the cells increases at cold temperatures, and that limits the useful rate (amps) at which you can extract that energy.

3. If you try to draw too many amps at cold temperatures the voltage sags, so you get less power (watts) but especially important, the voltage can sag to a point that it can damage or degrade the life of the cell well before the packs rated capacity us used up. This low safe voltage limit is about 2.7 or 2.8 volts for the most commonly used Li-ion ir Li-polymer cells.

So, I suspect that EV designers "de-rate" the pack capacity to be sure cell voltages don't go too low at the amperages needed for drivability. The SOC goes down faster in cold weather because the battery management software raises the "pseudo" zero-point of the SOC to what is actually a higher SOC.

Smart EDs seem to be especially prone to decline in range in cold weather becasue:

- The current draw relative to the amp-hour capacity (The "C" parameter - where in the case of the smart 1C is 52 amps, 2C is 104 amps etc.) is higher becasue of their small battery.

- This requires a greater cold weather "de-rating" compared to larger battery-EV's.

- It also doesn't help things that the Smart ED has always had poor energy efficiency (miles per kWh or kWh/100 km) compared to other EVs. This has always been an inexplicable feature of the ED, because with it low weight, I would have expected it to be the most efficient EV on the market. Instead, it is one of the worst. My 600 lb bike+rider electric scooter gets about 11 mi/kWh - so low weight definitely should help even with poor aerodynamics.

And this is all before the added drain of using the heater.

We just have to enjoy our ED's/EQ's for what they are. I live in a fairly "compact" city where distances I ned to go are relatively short. But in more sprawling midwest/western US cities the Smarts ED/EQ's definitely have their limitations.
I think the bad efficiency is due to the low gearing of the reduction gear between motor and transaxle.
I think this is what gives the small motor the start off punch they wanted.
Mercedes has never and prob will never be about MPG KWPM or whatever other measurement is used.

I changed the oil in my transaxle, and my car efficiency did seem to improve.
colder weather and lighter oil would probably be a good thing also
 

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Discussion Starter #18
It was 21F when I started my 13 mile drive to the ferry today. It was about 25 when I finished. I ended up with 83% battery left, according to my OVMS. That 2% higher than normal in chilly weather.

I usually run the defroster a few times during my trip, but I lay off the heat otherwise. Wearing a coat in the car doesn't bother me, since I am about to walk to the ferry then hop on a bicycle.
How did you get your ocms going on your smart, mine never worked even once
 

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Discussion Starter #19
A while back I had looked at getting a water warming heater to plug into 120v while car is parked, and warm up the cooling system while parked. This would allow batteries to run at safe temps better and take load off of car systems.
Does anyone know the PIDS to allow torque to make guages to see these sensors?
 
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