Gen II Prius Individual Battery Module Replacement

Your best source of a complete battery would be Ebay, but remember all the internal modules would need to be changed over.
You could just swap out any faulty modules, but it would be a good idea to at least charge or discharge any replacement modules to the same voltage as the rest of the good modules in your battery.
If the replacement modules are higher in voltage than the good modules in your battery use a headlamp bulb across them until the voltages are the same.
If they are lower in voltage they will need to be charged up to the same voltage. This can be done with an ordinary 12 volt car battery charger a headlamp bulb and a volt meter. This would not take up much time or effort.
If you are very lucky and the battery voltages are the same you can just change them.
Going this route is quick but there are no guarantees as to how long it may work, could be weeks could be years.
Let me know what you decide to do, and if I can be of any help just ask.

John.

 

I found a generation 3 Prius hybrid battery out 3 weeks from a 59 reg salvage.

The seller is looking for 450 pounds including postage to Ireland.

Money seems a bit high for a 5 year old battery.

I priced the battery in northern Ireland and they said 1068 pounds for the battery alone and probably another 100 to install and they would need my bad battery back as well.

What's your view on it?

Another thing I wanted to ask is why do you think that Toyota guarantee a replacement hybrid battery for one 1 year. Is there a chance it is not the same as the original?

Also, now that the generation 3 battery has been in production for over 5 years, do you think Toyota user the same cells for the new/replacement batteries in generation 2 Prius?

GT-I9100 ?

 

Considering how close that was, did you talk to Toyota? They may do a goodwill full or part reimbursement. It's in their best interest, good public relations...

And BTW, this is a very good thread!

 

If you can buy wire and solder, you can balance the pack in a few hours A few tips I might add are to take the modules from the ends of the pack and switch them with the modules from the middle. The modules in the middle are typically the first to die as they remain hotter, longer. Secondly, check out the orange bus bar on the right hand side of the battery...You will notice these silver square tabs. These are sensors and they transfer electricity to the modules. I have noticed that about 90% of the failed modules are directly connected to these sensors. What I do, and this may all be in vain, is switch the modules that are on the sensors with ones that have not been. It's an extra little step, but I believe that it helps. Also, if you are rebuilding your battery, might as well clean it. I like to chemically clean the copper plates located in the bus bars and then I wire wheel them to remove corrosion. If I think of anymore tips I will post them soon


Jessica

 

Hello Mendel, I did speak to Toyota but they don't give a dam and have flatly refused any assistance.

GT-I9100 ?

 

That's a great testimony to rebuilt batteries! I am sure you will have MANY more miles on your pack. Good luck and keep us updated!
Jessica

 

Those are the endings for, quoting Toyota tech specs: "Voltage Detective Lines" - their role is not to transfer electricity to the modules. Name explains the purpose. The faults sometimes could be caused by those lines being corroded all way through from the module up to the battery controller! That fault is almost impossible to notice for unsuspecting user.

Take magnifying glass and have a closer look at where the copper wire is connected to that square silver looking connetor.
It is crimp type connection. If the wire is black - it is corroded (should be nice shiny copper looking).
On the other end those wires end up in an orange connector. Pins are crimped to the wires. Take out one pin at a time (hope you know the procedure) and check it out for the same symptoms - if it's black - the whole wire should be replaced. The worse condition I found in many packs were within the first 5-7 wires from the most negative side.

 

I read that the "voltage detective lines" transfer electricity to help equalize the banks. I will look for the article.

Jessica

 

So theoretically you can take apart a good battery pack and move the center cells to the ends without having to re-balance anything? Just put everything back together again and it's good to go?

 

If its a perfect battery pack, should be fine. But if not, bad cells need to be replaced first. If the OP didn't have a way to balance modules within a preferable range I suggest at least loading up the middle of the pack with his highest capacity modules. The modules in the center take the most abuse, so its good to put your best guys in the middle so to speak. I highly recommend trying to balance the pack obviously, but I know that is not always an option for some people. All of this is based off of data compiled from the many rebuilds I have done.
Jessica

 

How long do you think it would take to take apart the battery and move the cells from the center out? This sounds like a good way to extend the life of a pack.

 

If you have the right tools it takes about 30-45 minutes. The most annoying part is getting it back together...

 

Maybe that could be a new service you can offer . Hybrid battery maintenance. 1. Clean the fan and move around the cells to prolong the life. I would do it if it were offered!

 

There's a guy in my area who does something similar for $450. I'd do it for a iced coffee.
Jessica

 

ok, I have to make a drive to Houston and bring 2 iced coffees, just in case.

 

Recent Battery Overhaul Adventure Tips.

I recently followed these forums and some youtube videos and successfully overhauled my battery. Hopefully it will last, if not I will post on here the life expectancy of my setup.

So I replaced all the Gen 2 cells in my pack with Gen 3 cells from a Junk yard, and added 4 reconditioned Gen 2 cells in the re-reconditioned pack.

Mistake #1- When reconnecting the side electrical strip (do not) connect the ground (black wire) last. I was either removing or reconnecting the modules and sparks flew. This damaged one of the battery modules "which tested ok" and only allowed my new pack to last around 15,000 miles before the slightly fried module gave up the ghost. When reconnected the modules or taking them apart, pull out the strip in the middle and try to get some slack and connect the ground first and screw it on, then start your way down and connect the positive last, also when disconnected, disconnect the ground last. On visual inspection it fried the module enough to melt the plastic slightly on one of the terminal ends. This battery charged and tested ok, but was not. The post on the friend end was a little loose too. So always check the posts for looseness. If you put the screw on and it keeps turning, toss the module it will fry in the future.

Mistake #2- You may find, or will find sometimes the modules all test perfectly, and even when you put a load on them with a light and test the voltage they still seem fine? How is this? I don't know, but in order to find out the real culprit you have to pull the battery out and disconnect/test it right after it has been used in the prius. So you want to either drive the car for awhile and immediately pull out the interior and the battery, or if you already have the interior out, run the prius for about 30 to 45 minutes to get a load on and off the battery. If you let it set over night I think the bad modules tend to try to rebalance themselves with the pack, which makes them hard to find with the voltmeter. If you run the car, stress the battery, and immediately after test the pack, it will be easier for you to diagnose. At the minimum get the pack out of the car and remove the bus bars, even then, these batteries tend to want to equalize on their own, so I would just test as soon as possible after running the car. This allowed me to find a bad module I couldn't find before.

Mistake #3- There are some great custom Torque apps to test the Prius battery, but don't follow the advice that tells you which battery block is bad, for some reason it was not accurate when I was testing mine. I replaced the bad block of two modules, then on re-test after re-shuffling the modules the bad modules appeared somewhere else? The apps are good to test the Min/max voltages to let you see the voltage spread between the modules just don't trust the battery bank locations, i think they are a bit mixed up in the app. However the Min/max voltages which is what you need tend to be spot on. When my triangle of death lit up, I checked the app via bluetooth obd-2 reader and indeed my Min/max voltage was out of the 1 volt max tolerance range. I think a decent used pack will probably be in the .10 to .20 Min/max voltage range. Anything wider than a .30 to .40 would probably start to be a concern. .50 to .70 and you should probably be thinking of replacing.
Goggle, artsautomotive predictive-battery-failure-analysis-for-the-prius-hybrid. I can't post the link for some reason.

Mistake #4- Do not tighten down the module posts "too much" I ended up snapping off one. These aren't heavy duty so don't crank down. Also don't use a power drill to tighten them, it's too much torque. You can use them for quick removal, but I would tighten down by hand.

I also, which I didn't want to do, but due to the cost of replacing multiple gen 3 cells, used a few gen 2 cells in the pack also, i reconditioned all these cells using the thunder battery charger. I'll let everyone know how they hold up being in a mixed pack. So far, so good though.

Lastly,
Thanks for everyone's help here on the posts. I wouldn't have been able to do it without all this info. If anyone has any questions feel free to ask, or if any info I posted does not seem correct please feel free to share your thoughts.

 

My car gave me the triangle last week. I hooked up my OBDII scanner and got P0A80 and P3018 (module 8 becomes week). This thread has helped quite a bit so thanks ryousideways. I was wondering if you ever made that step by step to reconditioning the battery that you planned on making. The info I've gotten here will be a help but this is my first time fixing ANYTHING on my '05 with 260000 miles (besides routine maintenance). It seems stupid to spend over $1,000 on replacing a battery on a car with so many miles. I already bought the replacement module, pulled the battery out, and now I'm waiting on my rc chargers to arrive. My only question is how do you go about draining and charging the batteries? Is it going to be obvious after the chargers get here? It does need to be done 3 times per module right? What should I charge them up to? and what settings will I need to use on the charger/discharger?

Quick disclaimer... I'm an engineering student but NOT electrical engineering. I steered clear of that field for a reason lol.

 

also... how do you load test the modules and what should I expect from a good module and bad? Like I said, I'm a quick study but know next to nothing about electronics. Thanks in advance for any and all help!!!

 

You may wish to read through the Method Of Procedure at
Testing Complex » HYBRIDS
If you use RC Charger/Discharger it will take forever though...Use built-in safety features - i.e. maximum capacity 6.5AH when charging fully discharged module, 6V minimum when discharging etc.