pipp
Member
Hi guys, I just picked up a RWD M3 yesterday, and am just trying to make sense of the best practices for charging given my current living situation. Living in an apartment complex, there are outlets in the garage. I drive less than 15 miles each day. With that information, I should be able to charge at night on the 110 to keep it topped off almost every day, and I would be confident to get it to 100% over the weekend. There are super chargers very close by, however.
So my question is should I go with this plan of 110V charging primarily, and use the SC only when necessary, or can I use the SC maybe once a week to get to 100% and be done with it that way? I don’t know if using the 110V every day (and not getting to 100%) will mess up the battery, or if NOT charging during the week and just charging at the Superchargers once a week to 100% is better?? Thanks in advance.
I rarely charge to 100% any more. I charge to 55%. (though, when I was using 110 volts the first 3 months I had the car I was charging to 100%). I am reasonably confident that my battery is not negatively impacted by this. The only question for me is if the battery management system is thrown off when it calculates what mileage range my car has left in the battery. Yesterday at 55% it calculated my range to be 132. 132 is 55% of 240, which is 13 miles less than when I originally bought the car 1.5 years ago. I wish the range still calculated at 253 (or, at 55%, 139.5), but as it is I think the range loss (roughly 5% in 1.5 years) is well within normal expectations.
Last July I ran the battery down to about 6 miles of remaining range, no telling how much more I could have gone. But that means to me that I can count on the car to calculate my range correctly to within 6 miles, which to me is close enough for horse shoes and hand grenades, as I almost never use up enough battery to fall below 60 miles of range.
So as far as I am concerned, I’m giving the battery less stress by keeping the charge at 55% or less, and the BMS doesn’t appear to be bothered that much by the fact I don’t charge to 100% once a week. And when I go on trips I’ll go ahead and charge it up to 100%.
So bottom line, don’t bother with the supercharger unless you’re going on a trip.