Will 5 month annual storage degrade Hybrid battery despite trickle charger on 12 v battery?

Your trickle charger recharges only the 12v battery which is only used to power-up the
computers in your Prius. So the Hybrid Battery is separate and being a battery is will discharge
over time.
If possible I would have some drive my Prius every month for about 30 minutes so all fluids get
warmed-up also.

 

From page 30 of the Owner's Manual:



That said, our 2010 had build date August 2009, and when we purchased in November 2010 it had 15 kms on the odometer (yes: 15 kms, not 15,000 kms). It's been fine, no issues. Maybe a brand-new battery takes protracted downtime better, not sure.

Can you get someone to "take it under their wing", drive it periodically? If push comes to shove, hire someone vetted, say a dealership person, mechanic or whatever..

 

i'm just not comfortable leaving a hybrid for 5 months every year. i always advised my father against it as he went snow birding each season

 

It would be very hard on an see hybrid battery to sit unused that long.

You could buy a high voltage trickle charger for your HV pack. It would cost $600-$1000 depending on which one you chose. That could maintain the pack while you were gone.