Look what I found in the recycle bin

I rebuilt a few battery packs a few years ago for Habitat for Humanity. Now I only rebuilt the Nickel battery packs, Lithiums a bit beyond my comfort level. Contact your local 501 nonprofits and offer your services. If accepted them contact your local Home Deport and Lowes. I received more help then I could accept from them. They set aside about 40 packs from recycle just for me and of those I was able to rebuild about 10-12 re recycled the unusable. Back then only about 10 were Lithium which helped the flashlight addiction. Both offered half price on new for the 501’s so that ended the rebuilding for me.

I kept it open, honest and got help in the process. So, if your into Boy Scouts, Churches or other non profits groups you can offer your skill to help the community and reap the benefits of good cells. It’s a win win for all.

Here’s a fool proof method of getting all the packs from all the recycle bins everywhere. Just thought it up. Place an ad in craigslist thusly, “For sale: One lot of used batteries and battery packs from all types of rechargeable devices.” In the description of the ad just say something like, “Not sure what all is included, come see in person, pics not available, sorry.” Anyway, tell them that you just bought them and had a bunch of others packs you could not use and put them in this bin yesterday. Then tell them you realized you put the wrong batteries in the recycle bin and need to get them out. Your getting old, memory is fading, whatever. When they ask, “oh really?, then where are the correct ones you were going to leave? Tell them you just left Lowes or another HD closer to your jobsite… and that is where they are. Then even if they still hem and haw a little tell them that the seller may have left the ad on craigslist, but you doubt it because it was a few days ago(very important), then say, ”let me see if I can find the ad.” If they have not already given in, find the ad and show it to them exclaiming your excitement that the ad is still there(YES!! Here it is!!). If the pause is too long then say, “do you think I made alll this up just to get some defective battery packs?” Then say, maybe I need to talk to your supervisor. You probably won’t need to though.

Anyway, try it and post back. Seems like it could work. No need to make anyone feel stupid or dumb. You just have to lie your a$$ off. :smiling_imp:

I have been wondering about this myself. If I were to try to take something out of a recycling I’d bet I’d be detained until the police arrive.

Me too!

Warning: What I report below is dangerous. I don't advise anyone do the same. I'm take safety precautions that are not elaborated upon when using the pack as it has been stressed by the soldering and test usage as a car battery.

Been very slow in reporting on what I used the cells from the 40V pack I found and reported in Post 94 above. Wired the cells 5P4S to drive a 55watt HID. Really needed a bigger solder iron. Gonna need to monitor some of the joints. Didn't build the pack for high amps, but did use it to start a car several times. Was curious what voltage they would stabilize in the car (turned out to be 14.6v). That little T plug connector and the then 12ga wires got hot as heck fast. The cells and soldered wires stayed cool.

Left pic is top of the pack as it currently stands. The right pic is the bottom of the pack part way though assembly.

So you had 8 cells left over?

I STILL can’t get over that pack you found!

I found my first pack in the recycle bin to day that contains 2500mAh cells!
New pack, probably from a demo at HD.


This is a Black and Decker pack, not much of a circuit board and not enough connectors to the tool. Notice that the pack is direct drive to the tool.

This pack contains 5S1P, Samsung 25R’s
When I opened it, all 5 cells were sitting at 3.67V :slight_smile:

^
Those 20 cells are from a 40v pack like you reported in the OP. I haven’t decided what to do with that “58v” pack yet.

Nice find. I got one of those too when I pulled the 58v pack. Looks completely unused, but I haven’t touched it yet. Great to know it has 25R’s in it. Thanks for reporting.

lets see whats on the other side of that board.

I already peeked under the board when I first saw it. I didn’t see any power FETs. They would normally be switched on and off at high and low cutoffs. I am thinking they must be in the charger and tool. However I own a B&D tool that came with the 4.0Ah battery and the included charger is a wall wart. As I mentioned, this pack has direct drive to + and -
So how would this pack shut down when fully charged with that wall wart?

I definitely will investigate further.
I have already charged up 1 cell in circuit with my Opus. Charged to and held at 4.18V. That is a good sign. I am now doing a discharge test at 1A. I expect better than 2500mAh. I will post more info later

Test results of a single cell is 2536mAh

And the wall wart probably has circuitry in the plug that mates with each cell. So I figure high shutoff is in the charger, low shutoff in the tool.



With this wall wart charger these batteries take 10 hours to charge up :confounded:
Glad I got what so far seems to be a perfectly functioning battery. Now left to do is put it back together and wait 10 hours for the wart to charge it.
That second B&D pack in the background is a 4.0Ah double pack that came with the tool and charger.

^
Sweet. So the cells seem to be behaving as if new. Sounds like your idea that it may have been a display model is a definite possibility.

Read something the other day about packs that have no balancing circuit that rely on what I think they called Top Balancing. They said the charger used pulses that allowed cells that were topped off to self discharge slightly and thus let current flow through to the other other cells. Eventually, the every cell in the pack is topped off. I think they said it was a slow charging process.

^
Words of wisdom gauss163. I agree and will add a warning to the post. Thank you :slight_smile:

You are quite right.

I do all of my charging of drill packs, store bought or otherwise outside. At present I have 2 charging while I do yard work.
Also, the more cells in a pack the greater chance any one could fail. Bigger problem if there is one too.
Always assume the worst and act accordingly.

Also, anyone other than myself notice that the recycle bins are made of pretty heavy gauge steel?

OK, OK. Members solder blobs all over the place here and I get all the preaching? These 13Q can deliver 15A continuous and 30A bursts. The pack has 5P. That’s 150A to get the starter moving. Once moving, the current is much less. The weak point was the 12ga leads. The cells had no prob starting the car. Especially being at 18.4v. They didn’t even get warm. By the way. 5P means a cell can fail and there are still 4 cells to take up the slack. So bigger margin of failure. See the balancing jack? That’s so I can monitor the pack real time. I agree the masses need to be warned, but I know what I am doing.

I’m now reminded of the famous last words of a red neck. Hey you all, watch this.

Did you use it to jump start the car or start the car on it’s own?
Jump starting is a piece of cake for that pack.

Someone once pointed out to me that “only fanatics get anything done worthwhile” :slight_smile:

Yea, lets get down to the cold cranking amps. Lets see that pack start the car with no other battery attached. Then turn it off right away. Not sure how the alternator is going to feel about a bunch of li-ions connected to it….

I don’t know where gauss163 got jump starting from. I used the pack as the car battery to see what level the car would take it too in the absence of a lead-acid battery. The car (a 1995 Corsica with 3.1L V6) took it down to 14.6 volts. I wanted to know this as I am currently building a LiFePo4/Super Capacitor automotive battery.

Most cars are fine with 18v. Some people convert their cars to 16v batteries and those cars can go as high as 18-19 volts when running. Most report their cars start and run much better at the higher voltage.

The other day I found another very nice pack. This time a 5Ah DeWalt pack, and it looked brand new.

Look at the specs on this thing, 100Wh!!!

It has a state of charge meter on it but it didn’t light up, maybe the reason it was tossed. So I took it apart to see what was up. All cells were sitting at 2.67V, maybe just low enough that the charger wouldn’t recognize it. This pack contains 10 Samsung 25R’s.
So I charged this pack up manually, making sure all cells charged equally. I let it rest a day and then discharged it through a 3 ohm power resistor to measure the capacity.
Here are my data points, voltage measured across the 3 ohm resistor versus time in minutes.

This DeWalt pack has no Low Voltage Protection in the pack, it must be that DeWalt includes that in their tools. Because of that I had to monitor each cell as it was being discharged to make sure they all tracked the same so as not to over discharge any one. I shut the pack down at 14V as at that point each cell was at just about 2.80V while under load.

My capacity estimation for this pack is: (17.8V/3 ohms) * 50 minutes * (1 Hr/60 minutes)= 4.944Ah
This post explains why I use those numbers in my calculation.
I had to estimate the capacity of an 18V drill pack, here is how I did it.

it is not good to throw the half full battery away.

I found this huge Li-Ion battery pack in the recycle bin. What first caught my eye was the 3 brass “terminals” on the top and the digital readout. At the time I thought I found a portable power supply with binding post outputs and a readout. Turns out it was a battery pack for some sort of camera. This pack costs BIG MONEY when new.
Not much to say, here are the pics of the tear down of this pack.
Turns out the “Binding Posts” were just guides to slide this pack into the camera. :blush:


The digital readout, LCD?




13.6Ah and 204Wh pack!

At this point I thought I had 8 sub packs of 3 18650’s each. I took measurements across each subpack and it appeared as though 4 were dead. It turns out I was wrong.


This is what I think is the balancing board for charging and discharging this pack. I bought one that looks much like this to charge 4 cells in series off of eBay.

Now here is where I was mistaken about these sub packs. What I thought were 3P 18650’s are actually something entirely different. When I took voltage readings I measured some cells in the wrong places and got 0.0V for 4 of these 8. Turns out these are 1 cell each, and when I measured them using the correct lugs, each cell reads 3.60V :confounded:
This could have been a like new condition pack and I decided to ruin it taking it apart because I thought half the cells were bad.



I am on the road so I can’t test these cells for capacity, but because all cells were sitting at 3.60V and the pack looked to be VERY lightly used, or new, I may have destroyed a perfectly good pack out of curiosity.
I will post the results of the cell tests in a few days.
If they perform like new, at least I have the cells.