Well, IMO that’s ‘backwards’.
You don’t really know what is going on with a light discharge unless they fail so quickly and badly it’s obvious.
Since they are charged, it you had put them on discharge at a low rate in the charger, you’d already be done and know the working capacity at that discharge rate.
eh, i tried them again, the test results are same as last time, so either they are just at that capacity, or they are so broken that the capacity cannot be tested, at least not by s4+, so i give up, whatever, i got new batteries on the way anyway, im gonna throw them out
i just got a whole bunch of 35Es, and i put them in to charge and do cap test, i noticed that the amperage at which s4+ automatically determines for them to charge at are all different, some are 1A, some 1.5A, some 2A, and this is just from the first batch of 4! how does the s4+ determine that? i know it automatically decreases gradually as the battery is charged full, but i dont think thats what this is, because they were all around 80-90% capacity
Recall those issues with internal resistance? It’s not just the battery, a lot of it is the mechanism and contacts. The IR reading is the primary determining factor (I think). IR also changes with temperature and state of charge. I guess I’m not surprised you get a lot of different levels.
IMO, if you want to do this with some semblance of control you’ll start using manual for cap tests.
Do whatever you want for just charging. I almost never use auto even for charging.
Note - depending on the charger, meaning the algorithm programmed in to it, the initial charge state, and the level the charger ‘decided’ to start charging, all determine how the charger will ramp down. Ramping can start as low as 80%.
80-90% charge for shipping seems awfully high to me. There’s a lot of power available at that level.
I thought new rules were going to lower that to below the ‘usual’ 50%?
ya i actually just added in the new thread i made
“i just wanna add that, the resistance measures were different too, not in same ball park like the sofirn 18650s that i got, they were all around 40-50, but these, at least the first 4 (i got 8), they were ranging from 30s to 80s. i mean i know some people said the resistance measurements on chargers isnt always accurate, but i just wanted to mention that in case s4+ takes that into consideration when deciding the charging amperage.”
so i guess i was right, it is determined in relation to the resistance readings, even if they are not accurate. cuz the highest resistance one was the 1A, and i THINK the lowest one was 2A, and other 2 were 1.5A.
but if i dont use auto, i dont know what type of battery should use how much amp to charge, is there like a general rule of thumb? and what do you mean by ramping can start as slow as 80%? what is ramping down, discharging?
and i dont know anything about that, i have heard it once or twice, but i guess not yet? or maybe going forward? im assuming these have already been packaged for a while just waiting to be picked for shipping, maybe the new ones coming out they stop at 50%.
Lithium shipping charge standards has been 50% for a good while. The problem has been stock that is SO old even that has slowly discharged. Higher charge provides more power for potential fire threats.
I have a Nissan Leaf electric. I tend to keep the charge down at 30-40% when not being used.
Look at some of HJK battery/charger postings. Test/Review of Samsung INR18650-35E 3500mAh (Pink)
At some point the charge will start to decrease working toward termination. That’s the ramping down. Discharging amps should not have any ramping (voltage does drop). It goes where it is set until it hits the cut-off, then just stops.
Manufacturers give specs on charging and discharging rates. (See specs on link above). For 18650 I personally tend to use 0.5A if I’m in no hurry. 1.0A is not a problem. 2.0A is acceptable if in a hurry and it’s a quality battery. You can go higher, but that’s pushing it a bit. Larger batteries can be charged at higher rates. Small batteries, older batteries, lower rates.
The higher the charge rate, the more heating it may have. Higher resistance adds to the heating problem. Heat is not good for any battery. Higher rates detract a bit from longevity.
so theoretically, slower the better? im assuming 35E falls under “quality battery”? lol
also, since you seem to know awful lot about batteries, what do you make of this
That’s a long’ish thread. Are you asking about the 0.2 discharge rate?
Some people think slower charge is better. There’s a practical lower limit on that. 
For 18650 I don’t go below 0.5A, UNLESS, it’s an unknown cell (say, a power pack pull), and I’m being careful about initial charging during analysis of it’s quality. Excessive heating during charging is a bad sign.
Note - NiMh may not work well with charge too low. I use 0.5-0.7, sometimes 1.0 for AA. Battery may not terminate properly if set too low. NiMh and li-on are completely different chemistries. They terminate differently. NiMh is actually more difficult.
yes, specifically that comment, the reply from sofirn that i found on amazon, talking about their 21700 batteries being 0.2C discharge rate, like wtf?
The manufacturers set a ‘standard’ LOW discharge rate for capacity rating purposes, what they will advertise (honestly….we hope). The lower the rate, the higher the capacity ends up being. There is supposed to be an industry standard for specific chemistries and sizes.
I understand that, but for personal purposes I ignore it. I want to know what the battery will do at the discharge rates I intend for it. HJK’s discharge graphs are great for that. He uses a broad range of discharges. Look at where the capacity comes out depending on rate.
right, i understand the first part, either high drain rate, or high capacity, but 0.2C is WAY too low isnt it? most batteries 18650, 21700, 26650, they should be 10-30A, no? this being a 4000mah, 0.2C would make it 0.8A, how can any flashlight run on that?
did they get confused as to what i mean? or is there two different discharge rates? are you saying i should check HJK’s other 21700 battery reviews, look for ones that are 4000mah, and see what their rate is, and that would be a decent estimate to what this one should be?
I emphasize, 0.2A discharge is a RATING standard, NOT a USE standard or recommendation. It’s purely for the industry to have a standard to determine how they will rate their battery capacity. It allows batteries to (hopefully) be compared with some reliability.
Decent AAA NiMh will easily pull more than 0.2A.
so whats the point of this rating standard? is it of any use to us users? and is it possible to determine the use discharge rate from that?
You can see that brand X has 2000mAh, brand Y has 2500mAh, and brand Z has 3500mAh. That’s all.
It shows NOTHING about the discharge capabilities under a real world load.
If you find the actual recommended specs you ‘may’ have an idea what the battery might do, IF the manufacturer is honest and done their testing with some integrity.
As you have seen, some of the places batteries come from have no integrity what so ever. Specs are completely made up.
Starting to understand why we love HJK, and what an incredible service he provides? He tests real world use capabilities. Remarkable work.
right, i found a few 4000mah 21700 he tested
https://lygte-info.dk/review/batteries2012/Shockli%2021700%204000mAh%20(Black)%202018%20UK.html
https://lygte-info.dk/review/batteries2012/TrustFire%20IMR21700%204000mAh%20(Black)%202019%20UK.html
two of them are rated at 40A, just like the sofirn ones, one of them rated at 30A, but it looks like they all handle somewhere between 10-20A ish. u think its safe to assume sofirn is about the same?
No idea. Probably?
Are you getting seduced by high amp discharge capability? Not many things require much more than 10A. Very few more than 20A. (I’m not a vaper. Those things can have high power requirements I guess.)
There is always a price……
I read a bit of this thread here n there. You have got them all wrong my friend.
A lot of these 30A, 40A or even 50A are just model number in a way to fool people.
Read HKJ reviews properly. Read every single word might help you understand further if you have not.
no i dont need high discharge at all, but i also dont wanna risk it having low discharge, if the sofirn 21700 even has 10A, im happy, but the thing is theres no spec at all
yes i know, thats why i said what i said, they are rated at 30 40, but HJK found them to be below 20, where did u get the idea that i thought they can actually do 30 or 40?
You mentioned ’two of them are rated at 40A”… From the start, you have been mislead by this “40A” to be 40Amp. What I’m trying to explain is they are never rated at 40A(Ampere). Never has any seller claimed that they can do 40A(A as in Amp). 40A is just a name similar to Tom, Dick & Hairy.