replacing a bad cell do i need to balance all cells ?

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How many miles are on the odometer?

@fotomoto has a thread that you might be interested in reading.

My P0A080 fault code and battery rebuild | PriusChat

 

That isn't all! You have to ensure all the modules, including the one(s) you replaced matches the capacity and voltage of the existing modules in the pack.

You need to discharge/balance the pack at once, if you're grid charging it, or you go through the hobby charger way, which takes little bit of time.

You need to have also a scantool that could access the various HV battery block voltages before, and after installations.

Just doing a whack a mole approach, might only save you some months of repeating the same job again.

If all the modules aren't matched close to each other in terms of capacity and voltage, you'd have the same problem coming up, with poor MPGs.

 

You could still drive it for short trips. But the problem is when the battery gets to a severely deteriorated stage, there comes a time the car could just stall as you drive. In such situations, you've got to reset the ECU by disconnecting one of the 12V battery cables, or use a scantool to clear codes. Car starts immediately, and you now drive home, or to a dealership.

It may cause more issues, if for instance, only say, one module was affected, it could easily cause the other so-called good modules to fail too. Its called thermal runaway. Heat affects the nearby modules, and operating voltages/capacity now varies between then, causing the blower fans to come on.

PS: As long as the car isn't stalling yet, you could drive. But I hope you can cope with the cost of gasoline though?

 

Test all the modules and see if you could post their voltages here

 

The Prolong people, Hybrid Automotive now sell used modules too, matched to your mileage.

Replacement Toyota Prius Module - Hybrid Automotive

 

I just loaned out the charger and Discharger out here in the Bay Area last month.

Maybe a member with the setup will chime in, but not sure of anyone in NYC with the setup .

But loaning and sharing are good options.

 

See the link in my signature to see what I did when dealing with a failed batt.

GOOD LUCK!

 

Be sure its a low mileaged car, and that what seller is saying is really the truth!

Might be a good idea to buy a hobby charger to do that, and you're done, in say, some weeks or so.

We have members in here that sell same stuff. I don't think they would want to sell you some fake stuff, considering that they have a reputation to protect over here.

PS: If what he's saying is the truth about the salvaged issue, then its cool. But open your both eyes well.

 

You do not know what level of charge is on the replacement cell. You really need to balance the cells in the pack while monitoring, both charging & discharging to get a true picture of the battery pack condition.

 

ids,

This is a link to a thread I made a while back that documented replacing one module with no other "balancing" or charging performed. Although every experience will differ, it can at least show you what you could expect. Simply exchanging a module can have a range of levels of success. Sometime the battery will last a year or more, sometimes not so much. There's a bit of luck involved, but if you can get some apps to monitor it, at least you can see what's going on and plan accordingly.

Also, don't misinterpret module voltage as a sign of strength or weakness. (except for ones like you found that are very low ie 6.3 etc. modules with significantly low voltages typically have internal failures and aren't worth trying to use again).

Just Another HV Battery Thread and Experiments | PriusChat