Hi.. I am new here. I have a 2001 Prius that I got in Dec. of 2000 so it was one of the first out. Several months ago I had a problem with the small battery and had it replaced at Toyota. A few months later I had my warning lights come on again and took the car to Toyota. They said it would be close to 4K to replace my big battery along with a computer. My car had 134K at the time and Toyota corporate offered me $1000 off a new or certified Toyota but would not replace the battery. I found a mechanic willing to learn about cell replacement and ordered the two needed cells at $49 each off of ebay. Toyota teaches cell replacement to their mechanics but does not offer it to owners as a option for repair. The mechanic said I did not need to replace the computer which was over $1,100 of the 4K price. He charged me $576 for the work done and I am on the road again. He said if it happened again it would not cost as much. I asked him if he wanted to take on more cars for people who are in my same situation and he said "Sure." He is located in Simpsonville, South Carolina (close to Greenville, SC) and can be reached at Chuck's Automotive Repair 864-228-1661 . I bought the cells off ebay and had them shipped directly to him.