I own 2008 RX400H, with about 65000km. Yes, no mistake here, 2008 model bought new in summer of 2008. I only use it to drive around town, and I live in town, so mileage is very low indeed. Here is my question. It is pushing 10 years, and the lithium battery is warranted for 10 years. I service it in my dealer, who has been very good. I asked how much to replace the lithium battery should it go bad, and he answered about $5000. How long will the battery last? Should I consider trading it in while the battery still has a year of warranty?