This is a great set of cold weather strategies posted by Mach-Lee on the Mach E Forum:
I’d like to make a couple important points and share some charging strategies based on my testing results. The advice here is centered around this mantra for cold climates:
Keep the Mach-E plugged in as much as possible when the temperature is below freezing so the battery stays warm.
Why? Range is proportional to battery temperature, so you can gain range by simply heating the battery. Charging speed at a DC fast charger is also much faster with a warmer battery. And third, you stay warmer. Heat is in short supply at colder temps, so you want to use power from the wall to get your battery and cabin warmed up as much as possible before leaving.
Goal: Keep the battery above 0ºC/32ºF at all times while it is in use (driving or charging).
This is the minimum temperature for acceptable performance of a lithium battery. It only take a few kilowatts to heat up the pack. The small increase in cost is usually worth the extra performance and increased comfort.
Biggest Misconception: “I don’t have a set schedule so I can’t use Departure Times.”
Yes you can! The battery stays warm for a long time after preconditioning, for 2-6 hours.
Therefore you don’t need to worry about leaving exactly at a departure time if you don’t have a set schedule. Just set one sometime in the morning or afternoon. It’s okay to not leave at a departure time, you’re still benefiting yourself later on.
Tip: You can heat JUST THE BATTERY by setting a departure time in the FordPass app and setting the cabin temperature setting to OFF:
View attachment 5441
There are two levels of
battery heating:
- Staying on plug will keep the battery 0-5ºC (just above freezing), and will only heat during preferred charging times. The battery will periodically heat itself. Just plug in!
- Setting a departure time will heat the battery to 15ºC before warming the cabin. This will keep the battery above freezing for several hours even if you don’t depart at the departure time.
Note: A 15 minute remote start is not long enough to fully heat the Mach-E cabin in very cold weather. It requires more like 30 minutes to warm up. You can extend the remote start (+15 min) or set a departure time to get a full cabin warm up.
Note: 120V charging will still heat the battery, but very SLOWLY. The heater power is limited to about 1 kW (equal to input power) while charging on 120V. This is 6x slower than L2. As a result, battery heating can take up to 2-3 hours if the battery is very cold. Likewise preconditioning is also very slow, so the battery and cabin may not be fully heated after a 120V preconditioning event. In very extreme cold, the battery may never be able to warm up fully on L1 charging even while drawing power 24/7. If you live in a cold climate, I strongly recommend you charge with 240V so you have the full 6 kW heater power available.
Mach-Lee Battery Warming/Charging Strategies:
[These all require to you be plugged in.]
-Strategy A - Just stay plugged in
This is the easiest way to keep the battery somewhat warm. It doesn’t require much thinking or any programming. When you get home (or to work) just plug in your car (do this everyday). The Mach-E will keep the battery above freezing. Works similar to a block heater on an ICE.
-Strategy B - Regular departure times
If you leave for work at a regular time, then set regular departure times. If you can charge at work, then set a second departure time for when you shift ends.
-Strategy C - Battery-only departure + Remote start ✱Mach-Lee Preferred 👍
This is best if you don’t have a set schedule. Imagine a 3-6 hour window around times you might usually leave, and pick the time at the beginning of that window. For example, if you usually leave in the afternoon, you might pick noon. Then the battery will be reasonably warm and ready throughout the day. Make a departure time in the FordPass app with that time and
set the cabin heating to OFF. Then when you’re ready to leave, remote start the vehicle. The battery will still be somewhat warm from the departure time hours prior. If you don’t know what times, use 7AM and 2PM.
I strongly recommend the above combination of a recent battery-only departure time + remote start when you are ready to leave.
-Strategy D - Irregular departure times
If you don’t have a set schedule, but can plan ahead 20-60 minutes, then just set a departure time in the FordPass app about 30 minutes in advance. This is better than nothing. The battery will heat a little bit and the cabin will warm up the best it can in the available time.
-Strategy G - Park in a heated garage
If you have the luxury, you can do this and not have to plug in. In winter climates I recommend you keep your garage at about 5ºC/40ºF to save energy, and use remote start before leaving.
-Strategy I - Drop charge rate to prolong charging
If you have an adjustable rate L2 EVSE, you can drop the charge rate down (e.g. 16A) to prolong charging. The battery is kept warm while L2 charging, so charging can be used as a heating strategy. You can make the car charge all day, therefore it's ready to drive all day. Just bump the amps back up above 26A before remote starting so you can cover the heater demand.
-Strategy Z - Delay charging until before departure
This one is special because it involves the manipulation of charging times. It works best if you charge the about same amount each day and leave around the same time. Rather than having your car charge in the evening, push your preferred charge times back so the charging window will start in the early AM (4AM), but early enough that charging will usually finish by the time you normally leave. Make the charge window as narrow and late as possible. Charge and go will eliminate standby heating losses, so it's the most efficient of all the strategies if you are concerned about saving every possible kWh.
Notice
Remote Start is not a warming strategy,
because it doesn't warm the battery! (Just the cabin.)
The charging strategies (I+Z) are between strategy A and departure times in terms of effectiveness. Departure times can be added to them to increase effectiveness.
If you are taking a trip with DCFC stops, I strongly recommend you set a departure time at the beginning of each day so the battery is warmer when you get to the first DCFC stop. This will speed up your charging times. Stopping at a DCFC every hour or two will help keep the battery warm for the whole trip. Turning the HVAC completely off for DCFC does dramatically improve the battery heating if you can tolerate it. The battery cannot be heated very much while the HVAC is on.
In terms of battery levels, I recommend keeping it in the usual 20-90% range year round. Remember 100% is only for trips, don't let it sit at 100%. Some people may want to bump up their charge levels in the winter to account for worse efficiency. Again, plug in as often as possible.
In summary, please install a 240V charger and adopt one of these warming strategies if you live in a winter climate. A lot of people don't recognize the importance of plugging in and the usefulness of departure times, and how they positively impact battery performance, range, and available heat. Last, a lot of people don't seem to understand that the battery stays warm for hours after a departure time, so setting one is still useful even if you don't leave at the prescribed time. The option to shut cabin heating off and just warm the battery with a strategic departure time is also underutilized.