[DealMeIn]

The SOC can drop or rise due to the temperature of the battery. As you drive, the battery heats up and will show a higher SOC than after it has cooled back down - I've had it go down 5-10% when the weather is cold (I live in the Chicago area, so it can be very cold). I've also had it go up as much as 5% when it is cold in the morning but heats up during the day.

It could also be an actual drain of the battery pack if it is charging a weak 12V battery a lot.

If you don't live in an area that gets cold, you should definitely check the 12V. $100+ for a new battery is a lot better than $10000 for a new battery pack if it should fail completely and take the pack with it.

 

[DealMeIn]

The cold temps are definitely at least part of it. Definitely recommend replacing the 12V battery sooner rather than later.

Your range loss is caused by using the heater. It eats around 10-15% of power all by itself - just watch the Power gauge when you are stopped and turn the heater on. If you have heated seats those are better to use than the heater. Personally, I never turn the heater on - I just dress for the weather and don't drive too far in the winter in the Smart

 

[DealMeIn]

When my windows fog, I use the air down all the way at 60 and output to the windshield (AC off, just plain air). Works just as well if not better than the heated defrost.

I haven't noticed any degradation in range since I bought mine. I've actually gotten more maximum range in the summertime each year - it's mostly due to the tires getting older and less sticky I expect along with being better at maximizing range covering any loss in the battery capacity