Even more traction battery rebuild questions

Hello all,

I'm in the middle of my second traction battery rebuild. You can read all about my first rebuild in this epic tale of human frustration and despair here:

Traction battery rebuild question | PriusChat

However, that car is running great a year and 14k miles later. We now have 3 Prii in the family and I'm rebuilding the battery in an '05, 165k mi car that's spent it's entire life in the hot gulf south.

I ordered the mini VCI w Techstream while the battery was disassembled, it would have been nice to have had it before I started, to compare numbers before and after, but it is what it is. I have a couple of questions for the community.

First, after reading every thread I could find, there seems to be some confusion about the module numbering system. Most of us count the module closest to the ecu as #1 and proceed down the battery to #28, on the other end. Others have stated this is backwards. So my first question is:

1) Can anyone verify the correct numbering system?

It doesn't really matter what numbers you use to refer to your modules, unless you're using the Techstream software to monitor the module pairs (banks). I replaced one obviously bad module (#26, 3rd from the end, was over 1 volt lower than the rest). The battery is back in the car, it's running fine, but I've left the interior trim out until I put a few hundred miles on the car. With the Techstream I saw that bank #2 is about .10v higher than most of the others, with about .23v difference between the highest and lowest banks. Bank #2 may or may not contain the module I replaced (my #26), so my next questions are:

2) How far apart do the highest and lowest voltages have to be to throw a code? and:

3) Can anyone elaborate on the numbering system Techstream uses for the 14 module pairs? How, exactly, are they laid out?

If the replaced module is indeed in bank #2 I will pull the pack and replace it with a better matched module. Or maybe a quarter volt is nothing to worry about, I need to know what difference will set a code.

I found a pack on Craig's List for $150 last year, most of the modules are good, so I have many to choose from:

My setup (by using 2 12v batteries to run my chargers I no longer get input errors):

Any info on banks/pairs will be of great help before I put the car back together.

YY

 

Thanks, guys. So the module I replaced (#26) was in bank #13, correct? I thought perhaps #1 and #28 were bank #1, then 2-3. 4-5, 6-7, etc.

I did a load test before I put the battery back in the car. I just put the charger on the modules (after balancing) with a .5a discharge and measured the drop:

1)7.93-7.92
2)7.97-7.96
3)7.94-7.93
4)7.88-7.87
5)7.93-7.92
6)7.96-7.95
7)8.09-8.07
8)7.88-7.87
9)8.13-8.11
10)7.91-7.90
11)7.86-7.84
12)7.95-7.94
13)7.86-7.85
14)7.89-7.88
15)8.02-8.00
16)7.90-7.88
17)7.95-7.93
18)8.02-8.00
19)7.93-7.92
20)7.90-7.89
21)7.91-7.89
22)7.97-7.96
23)7.90-7.89
24)7.99-7.98
25)7.94-7.93
26) old 6.70-6.66 new 8.40-8.38
27)7.90-7.89
28)7.88-7.86

I then connected the modules in parallel and let it sit overnight, checked that all the voltages were the same, and put the pack back in the car. It's running great so far!

YY

 

So the module I replaced (#26) is in bank #13, correct?

YY

 

What were the results (voltages) of the load testing?
Would be nice to see those too if you still have them.

They seem to be back in post #7 now. I don't know what happened.

YY