A month ago I had my 2006 150,000 GS450h battery refurbished by Richard at Hybrid Battery Solutions in Northampton. I had all the usual warning lights and a battery fan on. It cost me £800 and he even took me to/from the station. I have driven over 1000miles since and I am getting a better mpg. Highly recommended. I was quoted £2700 from local lexus dealer.