I just received a batch of 20 Sanyo/Panasonic GA cells today and was discharging 4 of them with my Lii-500 to get to 3V. Heated up quicker and more than i’d ever observed with my previous GA’s so i switched it off, from 3.51V to 3.41V, only about 24 minutes. So i thought i’d try charging 2 at 1A once they cooled down, and everything seemed normal until they started getting warmer than usual again. They were up to 3.78V at that time, and the meter read 1100mAh. If that’s right, then from 3V to 4.2V that’d make a little more than 3500mAh, which i doubt is funny in hindsight, but i kinda remember less when charging my previous batch. Plug’s pretty warm too.
Any chance of fake GA’s out there? These ones are sporting the Panasonic wraps, with the QR code thing surrounded by letters and numbers on 4 sides and nothing else, so i can’t track their production date apparently. I got them on Alibaba from a company based in Shenzhen and paid for it with Paypal, so that probably makes them more legit right?
Also, put one of them at 3.51V into my TN12 and it barely hit half the lux in a ceiling bounce test as one GA i’ve been using, although the latter is near full. Is that normal? I mean, the lower the voltage the higher the amps drawn out, so output should still be more of less similar right?
Do you have a temp monitor? Take a few pictures of the batteries and post them.
And the lower the voltage the lower the output in most flashlights. Certain cc drivers can maintain output. But at 3.5 resting voltage not much juice left in it especially once the load is applied probably drops to 3.2-3.3 volts. Tests are done at a full 4.2volts for the highest numbwers. If it took 1100mah from 3.4 to 3.78 they could be real or maybe the old panna b rewrapped. Pictures will help.
How hot are we talking? Like warm to the touch or like its to hot to comfortable touch for more then a couple seconds. Or hot enough to burn or blister. When cells discharge they get much hotter then during charge. But charge at 1amp shpuldnt make them to hot to old. What do the ir readings say on the charger?
2900mAh from 3.43 to 4.19V… wow! the GA is now officially 4000mAh, the age of the 4000mAh 18650 is upon guys!
until i get the infrared themometer, hopefully within this week, i can only say it’s approximately 45 degrees, which… i know…. completely normal. Feels awkward man lol but then again it’s better to err on the side of caution and seeing that we’re dealing with Li here. I wonder where some people get the guts to test the batteries to anything above that, and here i am getting paranoid at a mere 45 celsius :person_facepalming:
I’ll post some pictures of the cells up later. My previous batch of GA’s were wrapped in plain wrappers but with the codes stamped. These ones are the regular ones i guess.
Look up the spec sheets on the cells you have it’s usually around 200c for them to vent. Its good to have a healthy fear. They’ll get hotter then 45 in a real hard driven light. And the outside tempature is lower then the internal battery tempature.
You really can’t use the charging amps as a measure of the battery’s capacity because some is just turned into heat. What did the discharge cycle show for the capacity?
alright… discharged to 2.9V, i got 3265 and 3330mAh, with the former sagging a little more than the latter, more so toward the end, at 1A after just under 7 hours. That sounds about right, they are genuine GA’s then. Do the codes at the bottom side of the cell mean anything? Like C73291W. Some of them have the same code.
The date marking for newer Sanyo’s is very difficult to see. You will need a lupe and some light coming from the right direction.
The marking is embossed into the red wrapping in two lines, approx 3cm long in direction from top to bottom of the cell.
I grabbed one of mine that says:
SANYO L
NCR18650GA 5317
The date code is 5317
where ‘5’ is year= 2015
‘3’ is month= march (codes is 1…9,X,Y,Z so Z is december).
‘17’ is day,
so fabricated 2015, march 17.
made doubly sure and there are none on mine at all, not on this new batch anyway. Any chance that the QR code under the wrapper might help with that too?
Ok, everything seems fine, they are real GA’s. Guess i just had to make doubly sure since i’d purchased these cells directly from a chinese factory, for the first time too.
Speaking of which, how much does everyone get your GA’s at? If anyone’s interested i’d be happy to PM you guys the source since i know now that i can trust them for sure, and since they’re the cheapest source i know at the moment. They’ll spot weld button tops too if required.
Were these the Blazer or Xtar? The Blazers I bought would not fit in many lights as they were to tight in the battery tube. l asked if the Xtar were any thinner, no was his answer.
I had KD ones delivered which fit ok. They also tested similar to the Blazers.