Is my hybrid battery toast, or just in need of a charge?

Then leave it along, and sell it. Don't waste your time or money.
If you had techstream, or the D8, you could do a better diagnoises on it.
Save the Prolong for your next Prius.

 

That’s what I did. As soon as the engine started misfiring, and the mechanic just shook his head and gave me the puppy dog eyes, I traded it in

 

Hi Steve,
Good luck with all this. I have 4 old Priuses so I need good luck too.

From what I understand the Prolong is not designed to revive a bad battery. It's designed to be used when a battery is still pretty good in order to cycle it deeper than the car does, and thus "prolong" the life of the battery.

And, despite what many claim, these battery cells are not really designed to be "restored". They wear out. There are some very long and detailed posts on here about restoring bad batteries and/or bad cells. You can maybe get some extra months/years/weeks out of old batteries and cells. But only maybe. A quicker and more effective way used by some is to buy a low mileage, and low age, battery from a junk yard from a crashed Prius and use all those cells. eBay salvage modules are a gamble.

Mixing "good" and "bad" modules in the battery results in a "bad" battery. You can limp along with this for a while (ask me how I know) but it can in no way be called a repair.

 

Hi Steve,
There are others on here far more familiar than I with the workings of Dr Prius. Hopefully some of those will chime in.

From the posters who have done in depth “successful” work at restoring batteries and modules - ie have got years of life out off bad batteries - I understanding that matching the capacity of modules is important. This can only be done by using various electronics and taking the HV bat apart.
Since you can have no idea of the eBay modules capacity until you buy them and test them, it adds more uncertainty. Judging modules on their voltage - how modules are sold on eBay - is probably worthless.

You can buy some modules and start the process but the chance of success is not high. Hence the idea of getting a low cycle, low mileage, low age battery from a wreck. The market for these is quite competitive so they aren’t cheap.

Whatever you decide to try it’s probably wise to plan on a lot of work and time. The only quick fix is replacement with a new OEM battery.

As I mentioned I have a few Priuses in limp along state. I charge the 12v bats daily, disconnect them every stop, and charge the HV bat weekly with a grid chargers, which works like the charging part of Prolong. It’s far from ideal but as long as the engine starts I can drive.

I also have a few complete HV bats but haven’t dedicated the time and effort to embarking on getting the cars’ HV bats sorted out. One reason being that these old cars have other faults too, and life is short.

Many characterize changing modules as whack a mole. Unless you dig deep I’m sure that’s what it is.

Good luck

John

 

They would read the codes, do a health check on the battery, and likely tell you a new battery is needed. How much is that these days, strill around $2K? Or was that pre-Covic, a lot higher now??

 

“good dealership”??

where pray tell can one be found?

 

That, my fellow, is your duty. After 7 decades of life if you require advice on that issue, I doubt you will ever find one. No offense intended, but you asked the question.

 

$2K?????? To that I would have to agree with a certain Circus personality from years ago: There’s a fool born every minute.

 

This was pre-COVID, cash and carry through some dealerships. That’s a thing of the past now?

im just curious, hyperbolic response not required.

 

$2200 from the dealership I checked. Then -$220 for veterans discount....
I saw where the hybrid pit is selling a complete engine for $2200, minus shipping.
Completely redone.... No bad.