Hybrid battery replacement using a new Toyota battery

Here’s an update, a couple weeks after swapping my hybrid battery.

The car is still running fine. No issues with the battery. This was a nice win for a Do It Yourselfer. I would not have attempted this without all the information found here on PriusChat.

The fuel economy issue has resolved itself. Initially I was getting about 10% poorer-than-average gas mileage. Now I’m getting about 5% better-than-average. That’s a surprise. Probably some of it is due to running on the summer gas blend, and the rest I may be imagining. So the only thing noteworthy is that I don’t have a persistent drop in fuel economy.

 

My high voltage battery is still doing fine. It's been nearly 2 1/2 years, no other expensive problems with the car at all. I did have to repair the "combo meter", which is the main dashboard display. They have electrolytic capacitors which tend to go bad and just need replacing. This is well covered in other peoples' posts so I won't describe. Dismantling the dashboard takes a little time. Fixing the circuit board by soldering in a new capacitor isn't hard if you've done any electronics work.

Otherwise just normal consumables and maintenance items.

I need to replace my spark plugs for the second time. Advice: Put anti-seize compound on the spark plug threads every time you change them. That way you won't have an expensive and difficult problem of a plug getting stuck. When they get stuck you can't remove them without buggering up the threads in the cylinder head. That would be a fix (I think) beyond my reach; it involves tapping new/bigger threads and installing a threaded insert, probably a Helicoil. I can install Helicoils, but not in as inaccessible a location as a Prius cylinder head. Use the anti-seize. Loctite and Permatex both have suitable products.

I still like this car quite a lot. This 2007 Prius is my first Toyota. I bought it used for $13k and I've been running it for about 9 years. Odometer is nothing really to brag about, roughly 206,000 miles. It isn't glamorous, but it sure is good, cheap, fun, RELIABLE transportation. I actually have two of them, having bought a second one (a 2009) for my girlfriend. She has never had such a trouble-free car.

As always, thanks everybody. This site is a big help because of you.

 

Update: Four years later, the high voltage drive battery is still doing fine. The voltage difference between the highest and lowest bank (a 'bank' is two cells in series, or roughly 16 volts) is about 0.1 volts, which is good. I've only put about 35000 miles on the car in four years (retired!).

Here is another helpful video on changing the 2nd Generation Prius high voltage battery by an entertaining YouTuber, Chris Fix.
He swapped in a complete set of battery cells bought from Electron Automotive. He said the cost for the cells was about $1500. Since these are used cells this is not an approach I would take. Currently a new complete battery from Toyota, like I bought 4 years ago is about $2000 and you get new everything. I still think getting brand new cells is worth the $500 difference.

His video gives a terrific view of the whole job, from start to finish. He does good video work. Recommended!