2001 generation 1 prius battery

You may also find helpful http://priuschat.com/forums/generation-1-prius-discussion/84017-nhw11-traction-battery-autopsy.html

 

The modules should hold a charge for several weeks. The ones that don't, i.e. 7V or less, are bad.

 

The sense wires that attach to the busbars are very delicate. I suggest you use an ohmmeter to verify that all of the wires are good before you reassemble the battery.

If you see electrolyte leaking from a module terminal, it would be good to clean that up so that the electrolyte won't provide a ground fault to the battery case.

 

Were you able to get replacement modules already?

 

The sense wires are very thin and attach to one of the orange busbars that electrically connect the 38 modules in series.

There's no problem with leaving everything disconnected. The main concern is that you remember how to put everything back together, including installing the replacement modules with the correct terminal polarity.

 

If you don't have good instructions already, and you search around for the service bulletin on battery resealing, the procedures are well described there. (I guess they might not go into removing the screws from the module bottoms to change a module out, but that's all that's left after the disassembly they do describe.)

A couple key points:

1. an inch-pound torque wrench when reattaching bus bars, to get the terminal nuts tight enough without overtightening and damaging modules.

2. a few hours wait period with no electrical activity in the battery (sounds like you're already there) before even thinking of loosening the compression bolts that attach the end plate to the battery carrier and to the rods that run across the top. Oddly, the instructions didn't cover why that's important, but electrical activity creates pressure in the modules and they will bulge or burst if the mechanical compression is released, so it's pretty important. For the same reason, make sure all the compression parts are installed and secured before electrical testing on reassembly.

Somewhere Bob Wilson has a photo of what overcharging can do to the battery even with all the compression provisions in place.

-Chap

 

Charging these modules is a very interesting process. When the charger detects the negative delta V and shut off, the temperature is already climbing, and continues to climb for about half an hour. As charging nears full, oxygen is produced at the negative electrode, which then passes to the positive electrode and creates heat at recombination. This recombination process takes a while to complete, judging by the continued rise in temperature after removing the charger. If not kept under compression until the temperature falls back down, the oxygen pressure will cause the module to swell.

 

Great thread, and promising start.

OP: work safe, take your time, and good luck!

 

Hobbit has the battery resealing instructing on his site: http://techno-fandom.org/~hobbit/cars/TIS/ileaf/toyssc/toysspdf/sscsourc/2004/40g/40gtech.pdf

I like the SuperMate DC6 as a low cost charger, you can find it at Dynam Supermate DC6 DC Multi 1-6S LiPo Charger/Discharger/Balancer. The only issue with it is that you need a 12V power supply.

Keeping the modules under compression while charging is crucial, as I mentioned.

 

Thanks for keeping us involved
Good Luck!