Isn’t the difference negligible though?
How much more discharge would you get from a cell charged to 4.284V compared to 4.2V, and how does that compare to how much less discharge you would get if you stopped the discharge at a voltage 2% higher than spec? It is the difference between those two values that would have to be 2% of total cell capacity in order for the 2% error in voltage to give you an actual 2% error in capacity testing.
I would expect a cell at 4.284V would drop to 4.2V in just seconds on a discharge test, and behave similarly at the bottom end of the range, making both values very low and the difference between them even lower.
I purchased the C4 because I have a bunch of different 18650 and 26650 cells from various sources and am curious how they are holding up.
I received it today and kind of wish I read all the comments here before I bought it…
If I choose Fast test, it discharges the cell and measures the amount of electricity it takes to fully charge it.
If I choose Normal test it fully charges it then discharges it and measures the amount of electricity needed to fully charge it.
If I understand this correctly, the first charge on the normal test is a waste of energy because it is not measured. Should I just mostly deplete a battery with normal use then only utilize the Fast test to periodically check the capacity?
Measuring the amount of energy released while it is being discharged is a more accurate measurement of the capacity of the battery and how much light my flashlight can produce with it. Do other budget friendly chargers operate this way?
You have not read the review properly:
*
NOR test of LiIon*
It is possible to select 300 or 500mA discharge and charge current.
The charge will first charge the battery, then discharge while measuring capacity and finally charge again.
It discharges to about 2.8V with constant current, i.e. no pwm.
IMO [Fast Charge] is not worth much.
NOR test is useful, and reasonably accurate.
For internal resistance it is better than the Opus, and MUCH better than the Lii-500, which is useless for IR.
That not only makes it a decent charger but a ‘best buy’ in that price category.
Perfect? No. But, a really good charger for the price.
Was gonna ax about this, but just saw this thread, lucky me.
My almighty Miboxer seems to generally agree with my Opus as far as capacity, but yep, my Zanflare seems to be about 10% high.
I got a few NexTorch light kits with 2000mAH cells. My Opus clocked in at about 2000mAH, more or less, but tossing them into the C4, they all clocked in at over 2200mAH. Yeah, that can’t be right…
Figure it’d get outvoted 2 to 1 just on empirical evidence, but if others are also saying the Zanf is consistently 10% over, well, that can’t be good. Is it a multiplicative factor, eg, 1.1×, or is it a constant offset, eg, 200mAH? I really don’t feel like “dialling in” the charger for all cases, so…
At the end of the NOR test, is the number displayed for the discharge only?
Is there a way to stop it and see the discharge capacity without charging it fully?
Mine was always wrong about true capacities, see post #46. I doubt it’s a constant offset as those Dolidadas were about 5.050mAh instead of 4.600mAh and the Samsung 35Es were about 3.700mAh instead of 3.500mAh. So, I would guess it’s a percentage you need to add. However, worst of all is that my C4 measured inconsistent as slot 2 was even more off than slot 1, 3 and 4. Gearbest claims this is just normal and within certain thresholds of tolerances. Well, I don’t agree with them as I need to be sure about consistent capacities before using multiple batteries in series.
Stop it? No unless you pull out the cells or unplug the device. But you can read the measured capacity on the display as soon as the discharge process has finished and the cells are being charged again.
As stated, you can’t stop it. you can hover tediously and catch it at the right moment. Why would you want to? You get the DC info.
You can do straight discharges in the Opus. It has more ‘abilities’ that either the C4 or the Lii-500.
I wonder if these chargers get made in ‘batches’ with some getting differently sourced components? That might shed some light on different experiences people have. A VERY popular hobby charger (IMAX B6) is also the most counterfeited of all the hobby chargers. The real one is pretty decent. Some of the fake ones seem to be OK. Some have pretty lousy accuracy. You have to be careful of what you buy, or get lucky.
I have an Opus, 2x Zanflare, 2x Lii-500, and 2 hobby chargers (not IMAX). IMO they are all close enough and good enough to do the job satisfactorily. I use whatever is handy or sometimes pick one for a particular job. I probably use the Lii-500 least now.
Got my new Zanflare C4 today and tested the IR on a set of six Samsung 30Qs that I purchased from Obtronics in May 18. The results are listed in the table below.
Internal Resistance Measurements (mΩ)
Cell
Slot One
Slot Two
Slot Three
Slot Four
Difference1
Std Dev2
1
32
12
14
34
22
10
2
54
20
50
36
34
13
3
20
26
56
20
36
15
4
34
50
32
32
18
10
5
30
20
22
18
12
6
6
20
76
18
38
58
22
1. The Difference is the Delta between the highest and lowest values for each cell.
2. The Standard Deviation is a statistical representation of the differences in the values for each cell.
While these IR values are more consistent and reasonable than those obtained with my LiitoKala Lii-500, they are not on par with those seen by HKJ above. Oh well.
Update: I added Standard Deviation to the above table and try to compare it somewhat to HKJs data. Here are HKJ's IR measurements for the Zanflare C4 as listed in his review above.
Now here is a table of values just looking at the "Battery" measurements. HKJ please forgive me if I've screwed this up somehow.
HKJ's "Battery"
Internal Resistance Measurements (mΩ)
Cell
Slot One
Slot Two
Slot Three
Slot Four
Difference1
Std Dev2
1
24
22
24
28
6
2
2
26
22
22
20
6
2
3
26
22
32
22
10
4
4
26
20
28
20
8
4
5
20
26
24
22
6
2
1. The Difference is the Delta between the highest and lowest values for each cell.
2. The Standard Deviation is a statistical representation of the differences in the values for each cell.
By looking at the Standard Deviations in both tables, one see that HJK got much better results with his Zanflare C4 IR measurements than I did with mine. For some reason, I felt as if I had to try to quantify this.
Just got my C4 a couple days ago . My button top 30Qs were all over the place and mostly higher than one would expect from new cells from Liionwholesale. I’m giving up on IR readings from budget chargers. Also , seems like too short of a CV stage as all came off the charger around 4.16 volts. The Miboxer charges them to 4.20 but takes longer to finish.
Tell me about it. I was agonising over which analysing charger to get, researched all the different types, etc., and ended up pretty much with 1 (or more) of each. :weary:
Just get more batteries, so you can use different chargers simultaneously. And what to do with all those batteries… well get more flashlights. Problem solved.
I guess I have to get out more. With summer here , it gets dark so late that I don’t even use my lights much. And they are like guns , no matter how many you own , you can only use one , maybe two at a time . So many lights and so little time.
