Hybrid battery questions

Based on my experience the age of your car is the biggest factor when it comes to battery failures. 75% of the batteries that I replaced last year were in 2007 Prius with mileage anywhere between 100,000 and 220,000 miles. I still get the 2006's regularly and occasionally an 05 or 04. Never anything newer than that. I think your safe for at least 2-3 years.
Also never heard of a battery damaging an invererter. That's normally caused by hooking up jumper cables backwards. New batteries are $2500 if you put it in yourself. And $3500 if you have the dealer put it in.

Matt

 

My 2009 Gen II has 108,000 miles on the odometer with no problems (so far) with the traction battery, and here's my preventative solution:
Prolong Battery Systems. Extending the life of your hybrid. – Hybrid Automotive
You might to do well to read all you can about Grid Charging to prolong the life of your hybrid battery - it's an easy to effect insurance policy! Good luck, and welcome to PriusChat! - hope this helps - Wil

 

in some ways , the dealer is right. your warranty is up, so being prepared is a good thing. but on average, it's probably closer to 150-175,000 miles. and many do much better of course. i wouldn't spend any time thinking about it.
i have never heard of the battery damaging the inverter, this is a strange statement. be prepared to replace the battery, or else the inverter can be affected. so as long as your prepared, the inverter won't be affected?

 

Is there any chance the dealership was advising you to change the 12 volt battery ($250) instead of the Hybrid battery? ($2500)

Incorrectly Jump starting the 12 volt battery could harm the inverter.

A 2009 with the original 12 volt battery would not be insane to replace. (Any more than 4 years is a bonus for a 12 volt car battery) The dealer should offer a 84 month warranty.

 

I replaced my hybrid battery after 125K miles in desert mountains in Arizona, probably the worst condition for batteries (heat and cycles). And it never totally failed. I noticed failing charge capacity in the hills and a slight decrease in fuel economy, so I proactively replaced it. I also heard the battery cooling fan coming on more often, a bad sign of heat in the battery. Yours should give some warning if you pay attention.

As others have said, a failed hybrid battery won't kill the inverter. That's one less thing to worry about.

Ditto the advice about paying close attention to the 12V battery.