I've owned my i3 REX for 6 months. I've a question regarding conditioning.

[Epicurus]

My questions are at the end the rest is verbose gearhead stuff.

This is my first post after lurking since July. Hello to all. I live in the Commonwealth of Virginia in DC metro. My seventeen year old daughter needed a car so I started looking for "my" car as I wanted to hand down my car (2011 Mercedes E350). I looked at a variety of cars and nearly bought a new MB GLC 300, very nice ride for any considering a small SUV. I drive in traffic nearly every day so adaptive CC (A-CC) was at the top of my list and the Merc has a great A-CC. The problem was few of the GLC models have it. The Merc was just year two of a new design and the popularity meant little discount and as soon as I found one it was sold. I'm 10 minutes from a BMW dealer and I started looking at the BMW X3. Similiar problem few had A-CC and the additional cost was high and the BMW system is not as good as the Merc IMHO.

I checked out most of the small SUV's on the market. I was very impressed with the Mercury. I nearly bought one but, I found that their A-CC not worthy of the name. So, I decided to head back to BMW to check inventory. I saw the i3 in the lot and we went on a test drive. I'm a 52 year old tree hugger for life (owning a farm next to a coal strip mine did it for me.) BTW my sales guy was very knowledgeable regarding the i3 he was their "go to guy" for the i Series DM me If you want his info. I almost bought a new 2017 i3 luckily I waited went home and for the first time I searched used i3's I was in depreciation heaven. I have a 2014 CPO which had 20k miles and I paid 40% less than the new one I was looking at. This is strictly a commuter car. I'm very happy with the ride as it is made for parking lots and parking garages which is where I often am going to meetings.

QUESTION- I've read threads and I understand setting departure four hours prior to departure means battery conditioning should be complete. I have a level two charger in my garage so I just keep it plugged in while conditioning. On a cold day like 20 degrees F does the battery conditioning once complete increase range? If not I really don't see value. I've seen my battery range drop 38% on a cold day.

 

[bwilson4web]

. . . I have a 2014 CPO which had 20k miles and I paid 40% less than the new one I was looking at. This is strictly a commuter car. I'm very happy with the ride as it is made for parking lots and parking garages which is where I often am going to meetings.

QUESTION- I've read threads and I understand setting departure four hours prior to departure means battery conditioning should be complete. I have a level two charger in my garage so I just keep it plugged in while conditioning. On a cold day like 20 degrees F does the battery conditioning once complete increase range? If not I really don't see value. I've seen my battery range drop 38% on a cold day.

I have a 2014 BMW i3-REx. Earlier this winter, I was doing cold weather studies of our Prius Prime but have turn my attention to the BMW.

Earlier this week, I charged the car in 40F weather. Then I enabled conditioning while doing some shopping:

You'll noticed that the conditioning spike started at the peak rate and then followed the asymptotic curve to 2kWh. I suspect the initial charge helped warm the battery so when conditioning started, there was a distinct energy addition. The data suggests 2kW might be the active heating load BUT I really don't have a way to separate battery charge from heater load.

The simple answer is YES it does increase the range by putting more charge in the car. Sad to say, we don't have metrics to quantify how much since we don't have a way to separate battery charge from heater load and thermal loss from the ambient temperature.

I strongly recommend looking at your tire pressure. I carry a self-stopping, 12V tire inflator to keep them hard and low-drag. When the temperature is below 50F, top them off, they will be low. In urban driving, rolling drag from under inflated tires is your enemy.

Bob Wilson

 

[jadnashuanh]

THe i3's battery pack is a good portion of the total weight of the car. The battery heater is a 1Kw device. It takes time to warm the battery, and depending on the outside temperature, may not actually warm it all that much! But, any warmth to the battery pack when below the optimum, will help it increase the available range. IN really cold situations, it won't come anywhere near close to approximating summertime ranges. Your best bet is to park it in a warmer place! I've seen the range drop easily over 20-miles after I moved the car from my garage, to outside, then got in the next morning - just because it was so cold outside!

The act of charging the battery will also help to warm it, so if you combined the charging start time and coordinated it with your intended departure time, your actual range may yet be greater since it will probably end up warmer than with just using the separate heating element.

There is a prototype battery that is more capable of warming itself...the amount of power used to warm it is offset by a larger increase in range. That one uses the heating element embedded in the structure of the battery itself and was self-powered. I don't know of anyone that's using that yet.

The loads shown above reinforce the observation that the 12A, 120vac OUC supplied is not big enough to leave with a full battery charge if you try to set both a departure time and condition the cabin.

FWIW, tire pressure will drop about 1psi/10-degrees F.