Load test results, cell replacement, only 1 bad cell module?!

They used a hobby charger charging one module at a time and balancing manually. A grid charger like the Prolong one from Hybrid Automotive speeds the process immensely, especially when used with their intelligent discharger. @jeff652 has developed a very good system.

 

Having read the many threads on battery repairs, it is fairly clear that cell replacements are lasting about 6 months, then another and another are needed every once in a while. This renders the car to a working, but unreliable condition. So the current math is: Prolong system $700 + good cells cost about $35 ~ $800 for the first repair plus $75 every 6ish months forever! And each repair takes 2-3 days of hard work with very heavy lifting. So two years will cost about $1000 vs $1650 for a battery that will work reliably for another 12+ years. Doesn't sound like "fun" to me!

 

Be sure to take your time, especially letting the pack rest before testing it.
We had one user here who got impatient even though he knew better. He ended up replacing the battery pack.

 

Regularly using the Prolong reconditioning system changes that scenario. People have got much longer life from the battery pack when reconditioned regularly.
It makes little sense to use the Prolong system only for repair and then neglect until the next failure.

 

I very much like the theory of the grid charging systems, but I am not convinced they do anything more than provide a placebo effect. A double-blind test, with a hundred cars or more, should be completed before any claims of value can be established. Especially at $700. It sure would be nice to hear from a couple dozen priuschatters who have used grid chargers to chime in. When and why did they get them? Were batteries replaced anyway?

 

I have read of some that have seen improvements after several cycles. I know @Raytheeagle uses one. He can likely remember other names.

 

Ya, I've read a few anecdotal reports of short-term positive, albeit inconclusive results. I've also read reports of brief success followed with battery replacements. $700 is a big gamble.

 

I do not recall any of the latter other than @jerrymildred who I mentioned in post 27.
You have been here longer than I though.

 

And then there is JerryMildred's catastrophe! Who would have known that driving the car soon after doing a routine charge would have totally destroyed his battery? I've read the Prolong instructions, and they sure don't mention that!!! Yikes!

 

Best choice for DIY for Gen 2 & 3 HV battery is a full new pack from Toyota at $1625. There is also an experimental kit for $1600, available in limited quantities, from a new vendor here on priuschat.

 

They do mention that as a recommendation. Perhaps @jerrymildred can convince @jeff652 to make it a mandatory part of the process.

If you are not going to discharge the pack, we recommend waiting 30 minutes after disconnecting the charger before driving the vehicle.

From Prolong Grid Charger User Guide - Hybrid Automotive

 

Good luck with the rebuild.

Also the $1625 from Toyota is not a number most people can get. Toyota reduced their wholesale pricing by about $300 on January 1st 2018. Meaning your total install cost if performed at a dealer should go down that much. If you walk up to a counter and want to buy one, they do not need to give you the new lower wholesale price (which is higher than $1625).

We are in a pretty cool time for battery tech. When the whack-a-mole game is no longer fun, you can then decide if you want to keep the car and spend the money to do it right, or to junk it, or to whack another mole and trade it in for a new Prius.

 

Thank you for a rechargeable battery expert opinion here. I know many, including Prius experts here have put many trouble-free miles on your new cell kits. @ericbecky put over 3000 miles on one before he put in another pack to trade in the car for a newer work car.

 

And now his pack is doing charity work keeping a customer's car alive as a loaner

 

So the prolong system temporarily (for 6-12 months) prolongs a failing battery? Just asking for my own knowledge and understanding