Lithium traction maintenance

I don't think that "keeping" it charged is really an issue because I don't THINK that is "self discharges" anywhere near the degree of other formulations AND doesn't really care what SOC it has going in......within reason.
Or to put it another way, as long as it has a charge from 20 to 80% to start with, "storage" should not be a problem.
Unless the interval is in years maybe.

 

quite the opposite. lithium, although there are different chemistries, prefers to be low to mid charge.

so much so, that toyota recommends storing the car for long periods discharged into the hv portion.

just because your phone and computer remain fully charged on the charger doesn't mean they like it. it just means no users are going to put up with a device at 40% all the time.

 

For Prius Prime, the manual says to keep the traction battery as low as it can get by driving in EV mode until it depletes and switch to HV mode. But this means I have no EV range for my next drive unless I do the charging, so I keep mine at 30-40% now for once a week drive I am doing.

 

Most high density high capacity LI batteries with impeded computer management systems will discharge them to 50% or less. You will see that in higher end DJI drones with their battery packs. You will literally need to update each individual battery pack when their is a firmware update for the equipment. Storing them at 100% reduces the life.