I have a 2010 model, just passed 70k miles and runs like new. Best quality vehicle ive ever owned by far. One concern I have is life expectancy of the main hybrid batter system etc, I replaced the 12 volt battery last year despite original battery testing over 90%.
Are there any signs when the main system might be slowly dying or whatever it does? In past regular car batteries for me at least we’re just dead. Not sure what a hybrid battery may do. Thanks you.

 

I've owned my 2010 Rx Hybrid for less than 3 months but have owned a Prius much longer.
There are signs of deteriorating. The mpgs dip a bit. Also the state of charge runs down quicker. I also noticed my car was running a bit rough. Then the flashing triangle.
So I ended up replacing the Hybrid battery 2.5 years ago with a $600 rebuilt one. So far so good.
I've seen rebuilt hybrid batteries for the 3RX for about 2k.

 

If you want to buy a high quality ODB2 bluetooth module, there are some apps that will do hybrid battery testing and reporting. I have an ODBLink MX+ for instance that works very well for me. I haven't actually gotten around to running the hybrid tests myself (mostly been using mine for performance and economy stats), but apparently the battery tests work by monitoring the performance of each battery cell (or cell block, don't remember exactly) over time to determine its state. Another I remember reading would require you to allow your battery to discharge (like leaving the car in neutral while in ready mode to force battery to deplete) and then charge up while monitoring cell voltage. They sound interesting, not sure how accurate.

One day I will try one. So far after 11 years and 140,000 miles still original traction battery and original 12V battery.

 

My wife's 2010 RX450h is about to hit 200k miles and is still on the original 12v and hybrid battery. There aren't any signs of degradation. I'm really surprised.

 

I have a 2011 Lexus RX450h with 114,000 miles and now that my traction battery is out of warranty I was curious as to how many Lexus RX450h owners have had to replace their traction batteries? Also, at what cost and how many miles did you have on your vehicle. I also recently replaced my 12V battery at 112K miles.

 

I bought my 10 RXh 7 months ago. The hybrid battery on that car was replaced at 96k miles by Lexus for the previous owner. I had to change my Prius battery at 122k miles.
The cost for Lexus to replace the battery is around 6.5k. But you could buy a decent refurbished for around 2.5k for the RX