Prius not being driven for a long time. How to keep the battery healthy?

drive a little bit weekly (the more the better). at the minimum at least start it and let it do a full warmup cycle weekly

 

When you say sitting, what do you mean exactly? Will it be stored and you will be absent or will you just be leaving it sit while you drive another vehicle?

If the latter the easiest thing would be to regularly drive it at least twice a week for 30 - 40 minutes each time.

If the former, you will need to have some kind of charging routine for both batteries. You will need to have a regime for the tires too.

 

Maybe give it to someone to use

 

yeah, that's not a good thing. you can force charge it before leaving it. but if no one can drive it regularly, or put a grid charger on it, you risk death by stagnation

 

yes, you don't need to drive it. once a week for a half hour or so would be great, but the more the better.
sitting for a long time lets the cells slowly go out of balance, especially on older batteries.

the bms will correct that every time you make it ready

 

No clue what the market is like down there now, but if it were anything like in the USA? I'd just sell the car and go get another in a year or so.

 

Rent it out as a stationary Prius camper on Airbnb
Climate controlled

 

Or just rent it out as is …

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