When my Prius's hybrid battery died, I swapped out the two bad cells (out of 28) for good ones. Cost of parts and labour: $300.

How long did that last?

I have a Prius that's at 100k right now. Repairing the battery is within my abilities but I'm concerned that if one or two cells fail, more will be right behind it.

It's lasted a year and 10,000 kms so far.

Did you do it at a dealership, at a non-affiliated garage, or yourself?

I could see how there could be situations when someone tries to sell you into changing all the cells, even when that’s not necessary.

My trusted mechanic, my second cousin did it for me. The only difficult part was lifting the traction battery.

So when your engine eventually fails in your ICE car and costs many thousands to replace, will you return to EVs?

Depends on how many miles are on it.

[delayed]

Knew a dude that was asked several grands for replacing his hybrid Yaris batteries. He couldn't afford it, so he drove everywhere with the old battery. Because of the extra weight, he ended up consuming more fuel than the purely ICE Yaris.

That shouldn’t work. In a Toyota hybrid it’s the electric motor that effectively starts driving, and is also responsible for starting the ICE. So the car doesn’t really work with the drive battery not working.