I mostly charge up at home (240V receptacle and L2 EVSE), and I limited my charge to stop at 80%. I’ve heard competing ideas about if that’s really necessary, but I usually drive <50mi each day, so I figured I don’t need to full range anyway. When we’re planning to take a trip or something with the car, I will charge fully the night before.
Polestar 2 LR owner here. I charge up to 90% as recommended by Polestar and Volvo (same batteries and drivetrains), or to 100% when I think I’ll need the extra range.
Whenever possible I charge at home over night when electricity is cheap-ish. It’s much more convenient (not to mention cheaper) than public chargers, and the slower charging speed compared to fast chargers is better for the battery. With 11kW it would take about seven hours to top up a near-empty battery, though I hardly ever arrive at home with less than 50%.
As a rule of thumb, lithium batteries are the happiest at around 75-80% charge and increasingly unhappy above 85%, so unless you need the extra range, 80-90% is a sensible upper limit. Regenerative braking may also be impacted above 85%, as the braking may produce more energy than the battery can take. Be aware though that a SoC below 15% is much more damaging to the battery than one above 85%.
Having said that, unless you do really bad things to your car on a regular basis, most studies so far have failed to demonstrate a significant difference in battery life attributed to charging behaviour, so whether you charge to 80% or 90%, charge your car once a week or leave it plugged in all night every night etc. probably doesn’t make any difference that would justify the trouble.
I charge at home and let it charge up to 70%. We rarely drive enough where it’s not back up to 70% the next day.
I’d love to hear what others do, too. I hope to drive my Mach-E into the ground so would love to preserve the life of my battery as best I can. I currently limit to 90% SoC but maybe I should reduce to 80%? I drive very little (less than 15 mile round trip for work), but drive much more on weekends. Should I even limit how often I charge to maybe once a week from home?
I think the 20-90% range is ideal for stress on the battery cells. Everyone I’ve talked to suggest “ABC” (Always Be Charging). When I’m topped up to 80%, my car doesn’t charge, but it does draw some current from the wall for load balancing, temperature control, etc. But I don’t think that negatively impacts the batteries.
It helps to know the type of car. I charge my F150L to 85% most of the time. Ford recommends 90% and sets that as the limit from the factory.
I am not yet an EV owner, but I have done some research into this question, it would appear that most brands batteries are actually pretty good with 10-20% degradation in 10 years good. So odds are you won’t charge enough to really affect it. I plan on charging it like I do my phone, so letting it get to 20% after like a few days of driving, then full charge overnight. My understanding is the battery degrades due to actual charge cycles, so constant charging in theory is more strenuous on the battery. I doubt my “optimizations” will result in more than 2 or 3 % better battery performance, if that.
We only charge our 2015 Leaf 24kwh with a granny charger on a 16a 240v circuit (Europe) and always to 100%, we’ve only used a DCFC 3 times in 16k KM’s, the first 2 were while we were waiting for our granny charger to arrive. I’ve taken regular readings of our SOH which was 88.77% 67434 KM’s and the last one I took was 84.74% 84763 KM’s, interestingly the SOH crept up for a period, before dropping back down and is currently on the upwards creep again.