Ryobi One+ Lithium & NiCd Tool Battery Teardown

It’s still May, and I’m still doing tool pack teardowns to get through the seemingly endless boxes of tool batteries in my office.  I’m a bit fuzzy on where they all came from, though I do faintly recall picking up a box of dead ones at some point in the past.


This is a companion discussion topic for the original entry at https://www.sevarg.net/2017/05/21/ryobi-one-lithium-nicd-tool-battery/

(Comments from Blogger)

2017-05-30 by Smart@ss

Rigid, Ryobi, and Milwaukee are made by the same company (TTI or something like that). Likely explains the pack similarities. I’d think they would “try out” changes (cost savings) on one brand and trickle up/down the brands if they work (read: save money).


2017-05-30 by Russell Graves

That would certainly explain the similarities!


2017-10-26 by Rick Holmes

“Performance Pro” by B&Q have absolutely identical battery packs to the Ryobi Ni-CD one. The only actual difference is the casing and the negative and positive terminals are the other way round. Many people have those tools now with dead batteries and no way of getting replacements, this would be a very easy fix :slight_smile:


2017-10-26 by Russell Graves

In general, rebuilding NiCd batteries is pretty easy, and most local Batteries+ type shops should be able to do that for you.


2018-07-08 by Ll

Reading through your battery tear down write-ups I think that I understand the following… Ryobi and Ridgid have put battery protection circuitry in the battery pack and Dewalt has put the protection circuitry in the tool. yes?

My /assumption/ is that Ryobi has gone this route to keep backwards compatibility with their older tools.


2018-07-09 by Russell Graves

That’s a fair generalization, at least on the stuff I’ve torn apart so far. I may be doing some more pack teardowns soon…


2019-06-28 by Unknown

I had a p102 which was drained, but managed to revive. But it does again. The cells show fully charged (individually and as a pack) /but shows only 7.8v at the stem terminals. Any idea whats wrong?


2019-07-01 by Russell Graves

No idea. It may have latched the low voltage condition and bricked the pack.


2019-10-03 by RUAVOL2

Couple of questions. Can you bump up the mAh on these units?
https://secondlifestorage.com/showthread.php?tid=5258
I have many P100 & P102’s. In the case of the 102 Lithium. Can you use a higher mAh capacity. I am seeing a lot of LG’s 18650 out there with a capacity of 3000 - 3500 mAh. Will that hurt me or destroy the unit if I buy them and put them in the 102? They seem to be almost as cheap and I am wondering if Mo is betta’ or does it matter? I have checked for sizing and they should fit as they are the same size just not same mAh. Anyone have thoughts or can advise I thank you.


2019-10-08 by Russell Graves

You can increase the capacity, but I wouldn’t go past about 2500mAh in a tool battery. In general, cells are either “power cells” (lots of amps, not that much capacity) or “energy cells” (lots of capacity, sag badly if you ask for a ton of amps). Tool packs use power cells, so going with an energy cell might not work as well. You’ll want to find a cell that’s happy at the 15A sustained/30A peak rating of the original cells, which probably puts you out of the 3000+mAh cell range.


2020-01-29 by byegorge

First I don’t know what ‘SEO’ is so please let me know if I do it. Ryobi 40 volt: Battery#1 charges fine but does not run the tools (hedge trimmer, weed wacker and blower) tried battery in all 3. Battery#2 same as #1 except a different BMS board works just fine in all 3 tools. Battery#1 has full voltage on the board where the cells connect but it does not make it to the external ground terminal of the battery. The only thing between those 2 points is a MOSFET on the board how did it charge through it but not discharge? #2 is different in that area of the board so I can’t even compare them to each other, besides #2 works. Any thoughts or ideas would be greatly appreciated I’m just a retired mechanic who cannot afford $100.00 tool batteries. Thanks George


2020-01-29 by Russell Graves

Unfortunately, troubleshooting these batteries is pretty difficult. You could probably hardwire the appropriate connections, though I’m not sure how well that would work on these. I don’t actually have any tools that use them, simply some packs to tear down.

SEO is “Search Engine Optimization” - it translates, in this context, to people posting rubbish comments that are nothing but an attempt to spam a link to their website more places on the internet so their site becomes popular. You get stuff like, “Your site is very valuable, I am bookmarking it to share! link_to_batteries_for_sale” or other comments along those lines. Basically, if your comment includes an irrelevant link, it won’t ever show up. I don’t mind links in comments - if they’re actually related to the post and other work people have done.


2020-08-18 by Llama Spit

The Ryobi lithium packs need a voltage or signal on the center top and/or lower terminal in order to “activate” and supply power to the main terminals. This is a safety measure to prevent the possibility of a short-circuit on the totally exposed main terminals, since a accidental short inside a toolbox would cause a massive discharge fire. This kind of “protection” is not needed on modern (other brand) Lithium packs as they all have recessed battery terminals. As for the connection protocol to get power out… I am still searching, but read somewhere that 3.3V on the center top terminal MIGHT work.


2020-08-18 by Llama Spit

Yes, you must use cells with sufficient discharge current for the application. Laptop batteries with >3000mAh capacity are only rated for 5A to 10A which is nowhere near enough.


2020-12-22 by Llama Spit

Ryobi puts the BMS inside the Battery Pack so that the tool is as cheap as possible. That’s so they can market based on “one battery suits hundreds of tools”. It also makes the connector considerably smaller and less complicated - a 5S pack needs at least 6 connectors for the cells, plus thermal and ID terminals, perhaps one more for the communications = 7 or 8 connections and they have to be robust. Most tools now days (end of 2020 have the BMS inside the pack… it makes more sense to put it in there.