My car is a 2007 RX 400h with 100k miles.

1. How long do the hybrid batteries tend to last?

2. Is there a way to test where the batteries are in its life cycle?

3. How much would new batteries cost?

There must be lots of people interested in these answers. My car is in perfect shape, which is amazing for a 17 year-old car.

 

My 2006 Highlander recently passed 250,000 miles no issues with the battery. Replacement high voltage battery runs about $2,500 plus installation.

 

I have a 2008 with 231K miles, MPG 26.8 and with original battery.

 

I wouldn't sweat it as the hybrid battery goes a long ways....I'd pay attention to the vents & fans, in front of your rear seat...

 

Typically up to 15 years for normal mileage, anything more than 15 years count yourself lucky. Toyota would have this data, but they would never release it.

 

Anecdotally, on he UK forums I don't recall seeing any older RX's being written off for a failed hybrid battery. Most common problems seem to be water intrusion and corrosion.

 

When the hybrid batteries go, what happens? Does the car work like a regular gas engine car?

 

Nope. Car stops working.

 

Low MPG, fast discharge/charge of traction battery (on battery display), errors