Jeansy's battery tests (new impedance tests)

Cheers Ralf, will look into that although I want to directly compare cells so will have to keep an eye for the 3.cut point or re-test the above.

Anybody have any requests, could do with a couple more so will be ordering soon

Well... I know I am not being creative but since you have calibrated equipment and most of us aren't fortunate enough... ;) TF Flame 14500s and 16340s, perhaps? Personally, I'd also be interested in seeing how various 10440s perform side-by-side. But I do realize that 10440s aren't particularly popular. Also, could you please add where you got your samples from? Thanks again.

Panasonics, HKE

Soshine & TF Flames, DX

Senybor, Scottish EBay seller

I have some 10440s on route (DX silver TF) for my Olight but couldn't find many, any links? At present I have no use for the other sizes but maybe some 14500s soon

Very nice Jeansy! Thanks for your hard work and the great details.

Sticky'd.

Excellent test, i like how you discharge to 3.3v if i understand correctly. This gives us single cell users a more realistic although lower figure. As the only way the discharge to 2.5v or even 3v is a multicell light or some fancy electronics. Some cells hold a higher voltage over the usefull part of the discharge cycle in a single cell light which translates to longer run times, although they might not show a higher capacity if taken down to 2.5v, it doesnt matter as the light will be putting out as much light as a glow worm by then anyway… +1 for the 14500/10440. I saw some 5000mah 18650’s on ebay it would be fun to test one of those, i find it frustrating that sellers can rip people off so openly. Oh well thank goodness for people testing and enlightening us.

Top post updated with trust fire 10440(silver) & 14500, both from Manafont, charged on delivery and first discharge, will update more when I have some time.

Unless indicated everything is at 1a discharge.

nice photos!! (i dont really understand why i am seeing there.. but they should be helpful once i get my first hobby charger)

Hi JEansy, did not see your thread. Interesting!

Yeah, i have the genuine IMAX B6 too. I see it to 2.6V termination. Just measured 2.82V termination on the DMM (UT-58E). So pretty high. ~ 0.2V difference.

Though low, it is definitely realistic and won't harm the cells, well not to the extent that we are using our lights and cells (we have way too many cells). Some drivers' LV protection do terminate at such levels, looking at the end open-circuit cell voltage after letting the cells rest. The PCB also does not cut in that early or with low amps.

For my pro photography - i have like 10 packs and whack the hell out of them sometimes (eg over the weekend i took nearly 8k frames over 4.5 full-day weddings relatively speaking, it was 20-11-2011 and 2 weeks ago it was 11-11-11...heh), i still have batteries that run pretty "ok" though i can feel that they have aged and don't hold a charge too well. But they have been with me for > 5 years!

Flashaholics with 20-30 18650s will never feel any "degradation" from over-discharging to 2.8V esp if you mix the cells around across your whole collection. Unless you use them daily 1 or 2 full cycles per day and tag a few to certain lights that you use often....then probably it could happen maybe in 2 or 3 years.

Ok, i quickly had access to our Hioki battery tester. This is a calibrated, dedicated battery tester, as you can see below it measures the DC voltage but much more interestingly the internal impedance. The tester is a great indicator of battery condition if results are trended. Low readings are better and give an indication of outright power avalible.

The tester doesnt look overly impressive but it retails in England at approx £1500 or approx $2000USD!

I will try and write up the complete results soon, at least two of all the cells were tested (bar the King Kong)

Which cell is the last one(pink)?

Values seem too low for me.

Sanyo cell is the pink ored from intl-outdoor.

Viffer, this is calibrated and used commercially. It is endorsed by Yuasa also. I would suggest other readings you have seen are high ;)

The tester probably uses AC impedance test, that gives a considerable lower value than DC impedance/resistance test (Like I do in my battery test).

Yes it uses an AC algorithm to measure impedances, the way our systems are tested this is the only reliable method without disruption, it is also quick and convenient. It matchs the results of our BitBox testers also which iirc use a simple 50hz waveform but at much higher currents, not suitable for these small cells tho as the minimum AC current is approx 10a

Wow thanks for doing this!! I was suspecting the volt meter on my hobby charger was all off-whack. Its reading about .15V low. I never really thought to meter the thing while discharging.

These readings are much lower than the rest of the testers.

Yes IR & mAh

Please only use these results to compare within themselves. My capacity readings are inline with others but I terminate the discharge early. The impedance readings are measured with dedicated, calibrated machine, this gives lower results than hobby charger calculations etc. the AC current will also interact differently to the protection circuits I suspect.

OK a quick look at the protected Panasonics avalible from DX, ok lets compare with a unprotected version bought from HKE last year:

So that was the most recent discharge, they have done about 4 cycles now and have increased slightly, most noticably on the second discharge. The cells were charged on a WPII v2

Protected #1 started at 4.24v and gave 2414mAh (i think the high DC is because i topped the cell off from a very high state of charge already)

Protected #2 started at 4.19v and gave 2561mAh

Compare those results with the unprotected, charged on the same charger and discharged on the same Imax at the same settings, the difference is between 205mAh and 48mAh. I realise two cells is a very limited comparision but its 2 better than none ;)

If anyone has protected Panasonics from the other suppliers please feel free to post pics for comparision, as always please dont compare my results to others but only with my other results, thanks.

I tested these a lot in another thread and got higher mAh, to get the most out of them they need to be discharged to 2.5v i like 3 volt cut off as thats about the lowest most of my torches can go, but at 3 volt there is mot much of a gain over cheaper batteries. These have come a long way down on price and are more common now. Ive been noticing a little less mAh with protected batteries while discharging & higher internal resistance as the pcb uses power from the cell to run, but it looks like yours where the other way round. Very good batteries. But the protected ones i got preformed so bad i had to remove the protection, the batteries work really well now and the seller has corrected the pcb issue. Other wise ill post my results.