I'm on the fence of buying a new, but old stock, laptop battery pack, that contains these red sanyo r1122 cells.
The pack is $10 and I have already bought one, checked the batteries and have 2400-2500 mAh in them, and resistance around 90 after charging.
Are they still considered good and useful cells?
Are they 2600s with blue/purple rings on top?
Light blue rings.
4 in a pack
http://www.fasttech.com/products/1420/10001901/1136603-authentic-sanyo-ur18650fm-18650-2600mah-3-7v
Four in a brand-new pack you say? Not bad at $2.50 each I would say
But are they still considered good, or kind of outdated?
Definitely not as ‘fresh’ as the current NCRs in the market, but for me still a good as those. No known fakes with those cells too.
Might they be UR18650A 2100 mAh batteries like the ones here?
These are the ones I meant
I’ve been using these in my soup can style lights, took them out at 3.4v and they took 2200mah+ in the charger. I’ve been struggling to find better laptop pulls. I figure 80% of the capacity is useable, compared to 50% with the NCR18650 I’ve found as well.
I use old Sanyo 2600 pulls in most of my lights. I even run my DRY with those, although I rarely take the DRY past low or medium since I never need more light than that >.< Have also run the DRY on DD for about 2 minutes before I got nervous and shut it down, but the cells seemed not to mind.
Someday when I can rationalize it, I’m gettin’ me one of those fancy chargers that estimates capacity and all that. I’ve measured internal resistance using the derivative method, but errors add up quickly, and I measured at the wrong point during the discharge, and my meter sucks, and etc., etc. So, above, when I say the cells seemed not to mind, I mean that they were all still at the same voltage and did not explode after running in DD for a few minutes 
Great to hear..I might grab one more pack then.
I’m still using about 3 Xtar cells which I believe to be protected Sanyo 2600 cells. HKJ’s data shows those old Sanyo cells compare favorably to newer cells IMO.
These are the only 18650s i bought new, they are very good and stay at higher voltages for longer then other batteries.
If your using a boost driver i would go for the 3400mAh Panasonics but in a linear driver light i like these cells.
I just ordered another pack!!
It would be interesting if you get the same set of Sanyo batteries. I have gotten same packs and got completely different set of batteries.
Let's wait and see