Help! Prius died while driving on highway.

As I was driving home from work, I began to pass the car ahead of me and once I reached 72mph I suddenly lost all acceleration and had to roll toward the shoulder. When I lost my acceleration, the dashboard was full of lights (VSC, Red triangle !, & the red car with a line through it. Once I reached the shoulder I shut the car off then tried to turn it back on. The car moved about 5mph using the battery power but then lost everything. The start button would only turn red with the lights remaining on the dash. I ended up getting the car toed home and have removed the "Electric motor" and tested each cell with none of them reading less than 7.4. I also took the 12v to be tested and it tested good. Anyone have a clue as to what's going on? 2005 with roughly 500k miles. The car has documentation for every repair/part done to the vehicle including oil changes. Ran flawless before this episode. Thanks!

 

The previous owner stuck in the code reader once I got it home and it read clear. Pretty senseless to put a good car out of its misery.

 

Unless the meter went whacky, it had 3/10 bars which should have been plenty.

 

I'm from a town of 2000, not everyone is out to rip someone off. I have put 30k miles on it myself. He was the second owner and put over 250k on it. Are you going anywhere with this irreverent info?

 

Is that common? Easy/cheap fix?

 

Not sure what brand he used. It's something he's always used on his cars. He's pretty knowledgable on cars, I am about the complete opposite, especially with the Prius.

 

NEMO, near Hannibal, MO. Roughly 4hrs from Branson.

 

He traveled to Texas weekly for work, I work on the RR. Tons of traveling for work