So I finally got a BT-C3400 (BT-C3100 2.2) to test my 50-60 laptop pull batteries. I popped 4 pink 2600mAh Samdung into it and it’s quick test had their internal resistance at 128, 131, 148, 151. What does that mean? What percentage of old and crappy are they? At what IR reading should I toss them out?
Does it matter if I do the capacity test and say a 2800mAh is showing 2500mAh? I guess I need to start marking my batteries with their current readings so I can tell if one is getting bad. Some of the newer Dell pulls I’m getting have 4.35v cells. I want to mod my charger so I can access the 3.7, 4.2, 4.35 switch to be accessible from the outside. Promises to be a totally bubba/ghetto project I have 200 18650 skins coming from Fasttech to make these look better.
while i am not new i do not have one of the fancy charger yet (2x lii 500 on the way)
that also measure IR
from what i know its the like NiMh cells (to a point) the newer LSD Low Self Discharge are better then the older non LSD cells that would loose all their power in weeks VS. months (or years)
it also effects the charging and use of them again from what i know cells with HIGHER IR will heat up more
but to the best of my knowledge no one has a used / puled cells IR chart
BTW most IR for new cells are less then 40
i use a lot of used / puled cells every week and i avoid / toss the ones that do not hold a charge (if i charge them to 4.xx 4.17 - 4.21) and they do not hold that after a couple of days i do not use them
i can also add that these old cells while they pack a punch BUT in comparison to new cells ….
i get ~6 hours in my light on 1 “good” used 2200mAh Sony, Samsung,
i get ~12 hours in the same light with a new 3400mAh NCR18650B
but hey 6 hours is 6 hours and i am not complaining
I believe if you look in the manual it will say in there somewhere that 20-80 milliohms (internal resistance) is the best quality, while over 400? maybe 500 milliohms is pretty much done for as far as internal resistance goes
To be honest I think IR tests with the Opus is meaningless. I’ve always gotten inconsistent results using that function. Here’s an example; I just tested the IR on a laptop pull on all the slots and got the following:
i do not have the OPUS i have the Lii-500
and i just found on it the iR to be useful
from my review of the Lii-500 mR matters (internal resistance) in terms of the time to charge clearly on my laptop pulls (good ones) the lower the mR the faster the charge even at the same rate
I have 200 18650 skins coming from Fasttech to make these look better.