I've ordered an Aptera with the 40kWh battery pack and FWD. If we assume a sunny period of time with local driving only, with an average of 20 miles per day, the charge level could climb a little every day. To maximize solar gain and battery life, would it make sense to start with a 50% charge level?
top of page
bottom of page
@fanfare Even for the least expensive 250-mile model you can easily keep it charged at 60% with plenty of range to spare.
An average daily drive will only drop it to 44% with 110 extra miles available to spare.
For over 5.5 years I've been keeping my 100-mile BEV at 60% & even THAT leaves me with 20 extra miles left over after a 40-mile US-avg. daily drive.
User-set max charge limit on solar was confirmed by one of the co-founders in a vid.
The original question for a car using FIVE PERCENT of its battery capacity daily, makes it extremely easy to keep it between 50% & 60% if you wanted!
Apparently it's even better to take it down to 20% than it is to take it up to 80%.
The more you keep it between 30% & 70% the better, compared to 20-80%, & ideal storage level is around 60%.
That's all according to details I've learned at batteryuniversity.com & PushEVs.com which are both pretty informative sites.
As you know, lithium batteries are under the least amount of stress when they are roughly half filled. So as #20116 mentioned, keeping it between 20 and 80% full will let your battery lead a long, low-stressed life. Keeping it in that range you'll still get about 60% of the full range, so about 240 miles with the 400 mile range rated battery. That and keeping the battery cool, which the solar powered AC will do, will give your battery a very long life.
Not sure you'd have a measurably longer life keeping it between 30 and 70%. Once we know who is supplying the cells, we can read detailed spec's about this particular battery's lifetime performance parameters.
If you like to pour over numbers & graphs, you may like this detailed government research presentation on the factors of battery degradation. https://www.nrel.gov/docs/fy14osti/62813.pdf
Not sure it makes much diff where in the 20-80% range you are. The amount of direct sunlight will make the biggest diff.