Re-celling a Ryobi 40V - Edit: Looks like the 30Q's I put in it were fake.

[docw009]

Short answer is that I could have bought a clone on amazon for 43 bucks for less work. Oh well, I repaired a 5Ah Ryobi tool battery that was ten years old. Every cell was dead at 0V,

On the older OP040 cases, the BMS is hard to remove, soldered to the cells at 13 positions, It did not work when I put on new Eve cells. Maybe overheated during removal or it was already failed. I set the battery aside and it drained all the new cells to zero volts. I think the BMS already had failed.

I ordered a new BMS from China. It's been redesigned, only attached in four spots to the cells, but I had to dremel cavities in the old casing to accomodate it. This time, I put in twenty "new" Samsung 30Q's I had bought in 2021. One cell immediately failed during the first charge and pulled the group to zero. I replaced the group and the pack works now,

The Samsung date code was 2H74 which I was never able to look it up originally in 2021. Google AI tells me it's fake, Makes sense. Never seen cells go bad so quick. Anyway, I will run the Ryobi and see what happens. Am scrapping the remaining cells from this lot.

 

[sternwake]

Seems the Samsung 30Q was subject to a lot of counterfeit operations late 2010's early 2020's.

They should weigh 45-46 grams, and have a code stamped on the cell body underneath the shrink wrap that should be able to be seen with a strong light.

I read about issues with supposed Authentic 30Q's with high self discharge taking out batteries, but how many of these reports were actually counterfeit cells is unknown.

What is your tool that uses the '40V' 10s2p Ryobi?

I recell'd a very old 1.5Ah 5s1p Ryobi. It had some LG 1500Ah 22 amp CDR cells and one had failed. The other 4 were OK. Still using them. I replaced the LG's with 2500 mah supposed 25 amp continuous Sunpower branded cells, which came in a 7s1p vaccuum. That Vaccuum battery got 7 Ampace JP30p1's, with 0.2mm Copper busbars, which turned it into an impressive tool.

 

[docw009]

I run the Ryobi's on a weedwhacker, a leaf blower,and occasionally on my ebikes,

I bought the 30Q's from batteryclearinghouse.com, about $1/cell in 2021. Stored them for several more years, I would check them oocasionally, and they always sat at the same 3.43V that they shipped at,

I did have a second battery built with these cells fail. I built a 13S-3P for my ebike a year ago, and many of the groups in the pack discharged over the winter. I thought it was the BMS. I haven't rebuilt that battery yet, but now I believe it's probably the the cells.

 

[BatteryMooch]

The Samsung date code was 2H74 which I was never able to look it up originally in 2021. Google AI tells me it's fake, Makes sense. Never seen cells go bad so quick.

AI cannot be trusted for anything related to the cells we use. It is wrong CONSTANTLY.

To see if your cells are fake…
- Remove (carefully) the wrap from one of the 30Q’s…is the top insulating ring self-adhesive or is it loose? Genuine cells are always loose but some fakes are too. Self-adhesive always = fake for a production cell (or it’s a rewrap).
- Check the bottom of the cell…are there one or more characters stamped into it, near the outer rim? Almost all Samsung cells have this.
- Check (with a magnifier or loupe) the venting disk under the top contact…are there one or more characters stamped into the disk? Samsungs have this too.
- Check the side of the can, near the top…is there printing on the can? The top line should have “30” in it. No printing or no “30” = not a 30Q.

 

[rafalg]

I had a batch of genuine Sanyo cells that failed miserably when put into a battery. Most of them looked good at first, kept the voltage etc, but weren't able to handle any load and started to die one by one when put to work.
The price was good though... Since that i have bought many 'no-name' brands (also from disassembly) and they fared much better. So i'm not a big believer in spotting the 'fake' cells - after all, if a producer can make a working cell with the right chemistry and components inside, why would they not fake the fine prints on the side or proper shrinkwrap? Just to make it obvious that it's a fake? I think the problem is that these 'almost new' cells from disassembly arent that fresh in fact, and you can't check that easily.
(or maybe the 'fakes' are just sloppy re-wraps of some old junk, sold on ebay by some random accounts, i don't know)

 

[BatteryMooch]

why would they not fake the fine prints on the side or proper shrinkwrap?

Because 99.99% of all the potential buyers for those cells don’t even think to check for these things. The counterfeiters are also obsessed with taking the minimum amount of time/expense to fake a cell…because they don’t have to do more than that. Only a tiny percentage of potential buyers will make the effort to check the cells, or know how to check the cells, or even know that fakes might exist.

Almost everyone just wants to buy the least expensive cell with the least amount of effort. And the counterfeiters know that. It’s why it’s such a profitable business.

I agree though, salvaged cells are often crap. There are a couple of decent vendors out there but they are few and far between compared to the huge numbers of places selling junk.