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I just assumed my 38 year old Sanyo batteries were not worth even thinking about using. I'm not a collector and just trying to learn a few things.

I see some folks just use the dead batteries for their shelf riders. I saw a set of red sanyos on ebay asking for $160!

I have a 3-6 cell yellow saddle packs, and 2-6 cell red saddle packs as well as 6 red matched cells still in the package. The assembled sets have .3-.5v (total pack). Is that meaningful at all?

The unassembled set averages .659v for a total of 3.952v. (I poked my probe through the plastic bag to measure each cell.) I wonder what they shipped at? Seems not too bad for a 38 year old pack.

Some of the assembled packs have some corrosion (leakage?) on the bottoms.
The unassembled pack is perfectly clean. The two Duratrax are 3.282v and 3.783v which is close to what the unassembled pack is. I don't believe I ever used those, they still have a different connector than what all the rest have, I might have used them when I first built but I think they are unused.
I there any real value here? I'm rebuilding my Ultima Pro and I have hopes I can get the old electronics to work. Yet to be determined.

I'm not looking to sell, just trying to evaluate what I have.

Generally if NiCd's aren't leaking they are still viable. NiCd's also cope with being in a long/deep discharge state.

People do collect old cells and yours look like they'll clean up well.

Did you mention in another thread that the storage these were all in was flooded at some point in time? The corrosion is possibly from the water.

Yes I did say that and forgot to mention it here. So yes, that could be the issue. Not sure how to tell the difference.

I am no expert, but the "bad" corrosion that indicates the battery is toast is usually powdery and greenish white. It is an acid leak/reaction. You see it often around the terminals on 1:1 car/truck lead acid batteries. You can neutralize it and clean it off with a baking soda and water mix, but it usually comes back.

The rust color as seen around the connections on Swath's batteries is sometimes just flux from the solder.

Nicads are pretty resilient, I picked up a bunch of packs with some buggies I bought and they had been sitting in a loft for about 12 years. Ran a few charge and discharge cycles through them and they all woke up again. Of course the limited capacity compared to modern batteries means no one is really interested in using them in runners unless you want the fully authentic vintage feel. Compare that with lipos that crap themselves if you just look at them the wrong way.

If they are in new, undamaged condition they are worth a lot of money because as soon as you tried racing them the shrinkwrap gets marked or damaged. A limited supply means there's a demand from those who really want to restore cars with a full set of period correct electrics in them, and to do that you usually have to have pretty deep pockets as finding all the accessories in new condition is usually a lot more difficult than finding kits and parts.Those parts are going to sit on a shelf so whether they work is irrelevant.

The others you can try and revive them by charging and discharging them a few times, this can wake them up again.

I have no clue what solder I used back then, not the same as what I used today I'm sure. So the theory that corrosion is from the flux could very well be true. Should I clean it off? Remove the shrink wrap, clean things up, resolder it and put new shrink wrap on em?

The Pro-Tech charger must not have been in the muck. The box is nice and clean the the charger is pretty pristine.
I opened it up to look inside.
If you notice the holes in the box, I drilled those to help cool the charger down better, I felt like it was getting pretty warm and heat is hard on electronics. I drilled holes in the side and on the bottom.

I get a kick out of that spring wound timer with the contacts in the top right of the pic. Pretty old school right there. Sorry for the sidetrack, I should keep this on the batteries.

I’d wager if you disassembled the packs and tested individual cells you may be able to reassemble decent packs.

JosephS wrote: ↑Fri Jun 06, 2025 9:49 pm I’d wager if you disassembled the packs and tested individual cells you may be able to reassemble decent packs.

I like that idea, why not.

I took a couple of the sets partially apart. I cleaned them up and they look better. The ends came out fairly clean and I had no sign of crumbly leakage material. They are still attached in sets of 3. If I try to take them apart I'm sure it will pull some of the covering off where the glue is. Doesn't make sense to desolder them. I did trim the wires off.
Opposite side, opposite end. I measured the voltages (no negative volts):
Red set 0.305 total
0.219 - - - 0.024
0.000 - - - 0.000
0.059 - - - 0.003

Yellow set 0.373 total
0.149 - - - 0.011
0.062 - - - 0.040
0.023 - - - 0.088

Is this just a resistor to drain the batteries? I made it, you would think I would know what it was. 35+ years ago seems to make some memories evaporate.

1911Colt wrote: ↑Fri Jun 06, 2025 9:26 am I am no expert, but the "bad" corrosion that indicates the battery is toast is usually powdery and greenish white. It is an acid leak/reaction. You see it often around the terminals on 1:1 car/truck lead acid batteries. You can neutralize it and clean it off with a baking soda and water mix, but it usually comes back.

The rust color as seen around the connections on Swath's batteries is sometimes just flux from the solder.

It seems your assessment is correct, I left one set together and cleaned up the rest. They cleaned up very nicely, the rusty looking stuff came off easily. No sign of crusty stuff.

Swath wrote: ↑Fri Jun 06, 2025 10:11 pm

JosephS wrote: ↑Fri Jun 06, 2025 9:49 pm I’d wager if you disassembled the packs and tested individual cells you may be able to reassemble decent packs.

I like that idea, why not.

I took all the packs apart except one. Cleaned up nicely. They are still glued together in sets of three. If I attempt to disassemble the sets I'm sure it will rip the casings.

Not sure what the plan is from here for these.

Swath wrote: ↑Sat Jun 07, 2025 7:38 pm Is this just a resistor to drain the batteries? I made it, you would think I would know what it was. 35+ years ago seems to make some memories evaporate.

I prefer the glowing resistor method, the 12v automotive light bulbs. I didn't make this one but I have used it.
.

I had something similar my father made for me in the early '90s which was brazed together. I'm guessing I got the concept and design from RCCA. The last time I saw it was several years ago and was missing a lightbulb or two. I may have finally thrown it out. I really didn't understand the concept of discharging, and simply thought you hooked batteries up to it until the bulbs were completely out before charging again.