Letter From Mitsu

[Don]

I got an interesting letter from Mitsubishi yesterday with some tips for cold weather operation

"Dear Mitsubishi iMiEV Owner,

Winter has arrived! With it comes the season of colder weather conditions.

The low ambient temperatures may decrease the efficiency of an electric vehicle's lithium-ion battery, charging capability, and regenerative braking performance.

Your iMiEV was engineered with features to help reduce the impact low ambient temperatures have on 100% electric vehicles. These features include:
--- * MiEV Remote System
--- * Drivers side heated seat
--- * Main drive lithium-ion battery warming system (if so equipped)

Here are some helpful tips and reminders to help you maximize the driving range of your electric vehicle in colder temperatures.

Preparation
1.) Ensure your tires are properly inflated
2.) Whenever possible, keep your iMiEV garaged or sheltered from outside elements - air temperature affects charging times and capacity
3.) Consider weather conditions when planning your trip
4.) Utilize your iMiEV Remote System to 'preheat' the vehicle and heated seat
5.) If your iMiEV is equipped with the 'Cold Zone Package' the Battery Warming System can prevent the main drive lithium-ion battery from becoming too cold to accept a charge.

While Driving
1.) Minimize the use of the vehicle's heater
--- a.) The vehicle heater consumes electric power from the main drive lithium-ion battery
--- b.) Use the seat heater (it is powered by the 12 volt auxiliary battery and not by the main drive lithium-ion battery) - One wonders if they realize where the 12 volt auxiliary battery gets it's power??
--- c.) Efficiently use defrosting and defogging. Once visibility is adequate, you may lower the blower speed
2.) Put the selector lever in the 'B' (Regenerative Brake Mode) or 'Eco' (ECO Mode) position according to road conditions
--- a.) Lift off the accelerator early in anticipation of coming to a complete stop. This maximizes energy regeneration and reduces lost energy (A good idea anytime you desire maximum range)
3.) Avoid frequent or rapid acceleration, highway speeds, and congested traffic conditions when possible (Another good idea for everyday driving)

Please see your Owners Manual for additional important information regarding these features, and more cold weather driving suggestions

Sincerely,

Mitsubishi Motors North America Inc."

Don

 

[leec]

I got an interesting letter from Mitsubishi yesterday with some tips for cold weather operation

"Dear Mitsubishi iMiEV Owner,

Winter has arrived! With it comes the season of colder weather conditions.

The low ambient temperatures may decrease the efficiency of an electric vehicle's lithium-ion battery, charging capability, and regenerative braking performance.

...

2.) Put the selector lever in the 'B' (Regenerative Brake Mode) or 'Eco' (ECO Mode) position according to road conditions
--- a.) Lift off the accelerator early in anticipation of coming to a complete stop. This maximizes energy regeneration and reduces lost energy (A good idea anytime you desire maximum range)

I wish they'd provide an option for no regen. Because it's only 70-80% efficient, any energy lost to regenerative braking when one doesn't anticipate to come to a complete stop (or intend to slow down at all) will limit maximum range and increase lost energy. This is a comment I've provided to Mitsu by various means. Feathering the accelerator to balance charge and discharge while coasting is annoying and can lead to leg strain when done over a day of driving.

 

[NeilBlanchard]

[I wish they'd provide an option for no regen. Because it's only 70-80% efficient, any energy lost to regenerative braking when one doesn't anticipate to come to a complete stop (or intend to slow down at all) will limit maximum range and increase lost energy. This is a comment I've provided to Mitsu by various means. Feathering the accelerator to balance charge and discharge while coasting is annoying and can lead to leg strain when done over a day of driving.

I agree completely. Free wheel coasting is by far the most efficient way to use the kinetic energy you "store" in your moving car - and you only lose the aero drag and some rolling drag that you always lose anyway. When you can coast easily and predictably - you end up learning to drive better, and you accelerate less which consumes less power to begin with. By using most of the kinetic energy for coasting and only a minimum of regen will yield longer ranges because it uses less energy and loses less energy because you *need* less regen and use the friction brakes only a fraction of the time.

 

[Don]

I got an interesting letter from Mitsubishi yesterday with some tips for cold weather operation

"Dear Mitsubishi iMiEV Owner,

Winter has arrived! With it comes the season of colder weather conditions.

The low ambient temperatures may decrease the efficiency of an electric vehicle's lithium-ion battery, charging capability, and regenerative braking performance.

...

2.) Put the selector lever in the 'B' (Regenerative Brake Mode) or 'Eco' (ECO Mode) position according to road conditions
--- a.) Lift off the accelerator early in anticipation of coming to a complete stop. This maximizes energy regeneration and reduces lost energy (A good idea anytime you desire maximum range)

I wish they'd provide an option for no regen. Because it's only 70-80% efficient, any energy lost to regenerative braking when one doesn't anticipate to come to a complete stop (or intend to slow down at all) will limit maximum range and increase lost energy. This is a comment I've provided to Mitsu by various means. Feathering the accelerator to balance charge and discharge while coasting is annoying and can lead to leg strain when done over a day of driving.

Honestly, after 6500 miles of driving exclusively in the B mode doing exactly what you say, I don't find it to be an issue at all. For more than 45 years I've driven only manual transmission cars which do begin to slow down as soon as you release pressure on the accelerator, so when I don't want to slow, I don't release the pedal, plain and simple. No 'leg strain' ever, not 'annoying' to me at all - Once learned, it's just automatic behavior, the same as not turning the steering wheel when you don't want to turn . . . . when I don't intend to slow, I don't release pressure on the pedal and I don't even think about it

My complaint to Mitsu would be the opposite of yours - I think they went way overboard trying to make the car mimic an ICE with an auto trans. I could see trying to emulate the good things about conventional cars, but why try to copy the bad things? I think Mitsu gave us the 'D' mode for folks who are used to driving without thinking . . . . it's as close to no regen as we're going to get

Don

 

[Vike]

Free wheel coasting is by far the most efficient way to use the kinetic energy you "store" in your moving car - and you only lose the aero drag and some rolling drag that you always lose anyway. When you can coast easily and predictably - you end up learning to drive better, and you accelerate less which consumes less power to begin with. By using most of the kinetic energy for coasting and only a minimum of regen will yield longer ranges because it uses less energy and loses less energy because you *need* less regen and use the friction brakes only a fraction of the time.

I really wish this was a configurable option for Drive and/or Eco modes. The closest we can get with the current controls is driving in 'D' and shifting to 'N' to coast. Toggling that a lot seems a bad idea, though, because (a) I'm not sure the shifter was intended for that sort of duty cycle, (b) I worry about the safety of coasting in N because of the reduced control in a reflex-driven response to fast-developing traffic events, and (c) I'm not sure if we get any regen at all from braking while in N.

I think the cleanest solution would be a dashboard switch similar to the one for ESC that would disable regen while coasting, instead only providing regen while braking. This would be useful to many EV drivers, as would visual braking feedback to let us know when we're doing regen vs. friction. I'd prefer that to a firmware patch to more or less permanently disable coasting regen, as there are still many traffic situations where I prefer "one pedal" driving, taking advantage of the aggressive regen and muted throttle response of Eco mode.

 

[Don]

[I wish they'd provide an option for no regen. Because it's only 70-80% efficient, any energy lost to regenerative braking when one doesn't anticipate to come to a complete stop (or intend to slow down at all) will limit maximum range and increase lost energy. This is a comment I've provided to Mitsu by various means. Feathering the accelerator to balance charge and discharge while coasting is annoying and can lead to leg strain when done over a day of driving.

I agree completely. Free wheel coasting is by far the most efficient way to use the kinetic energy you "store" in your moving car - and you only lose the aero drag and some rolling drag that you always lose anyway. When you can coast easily and predictably - you end up learning to drive better, and you accelerate less which consumes less power to begin with. By using most of the kinetic energy for coasting and only a minimum of regen will yield longer ranges because it uses less energy and loses less energy because you *need* less regen and use the friction brakes only a fraction of the time.

You're pretty much describing the way I drive everyday in the B mode, Neil - Feathering the throttle between accelerating and regenerative braking is freewheeling but it provides the distinct advantage of being able to easily alter your freewheel to add either slight acceleration or slight regenerative braking as the traffic situation warrants. I pretty much never touch the brake pedal until I'm down to 15 mph or so about 30 feet from a stoplight/sign

I drove around all summer running the air conditioning every day getting real world ranges of 75 or 80 miles, so I don't see how a 'freewheel mode' would benefit me in any way - In such a mode I'd be tapping the brake pedal when the guy in front of me does. Instead, I just feather out of the the pedal for more regen and I seldom waste any kinetic energy by using the friction brakes. A 70 to 80% return using as much regen as I can get is far better than the zero return you get using friction brakes

Don