Oh boy… I had a feeling this was going to end up being the case.
I guess I’ll have to wait & see. They should be here in a day or two anyhow.
This may be a captain obvious comment, but, is it possible Molicel could be getting different guage insulators & shrink wrap from time to time, run to run?
Ok, well, I received the cells.
I can confirm, all 4 of them look just like @1stein 's pictures with a very slight protrusion.
If it’s useful for comparison, my date codes are-
109 2N120 03
Thanks for the helpful posts folks.
Perhaps. Differences from wrap thicknesses would be minimal but the top ring thickness might vary some.
Length changes between batches (or even within a batch) could also be due to different assembly lines being used, different batches or sources of metal top contact structures, different top contact sealing ring batches, metal can mold wear, and other can assembly stuff like that.
Hi all, recently bought some P45B cells from Illumn. Also got in a Vapcell S4 plus V3 charger from Wurkkos. I’m getting a little low results on the Capacity test and am wondering if this is valid for a new cell literally first discharge and charge. It seems a little low? Charger was left in auto mode. Should it be closer to 4500mAh?
Don’t know if it belongs here or in a Vapcell charger thread
New li-ion cells from the larger manufacturers don’t need “breaking in” unless they’ve been sitting around for a crazy long time. Yes, your results should be above the 4300mAh min spec, up near the 4500mAh typical spec. Those readings you got are very low.
Are your discharges from 4.2V down to 2.5V? I measured 4375mAh and 4401mAh for the two 2022-dated P45B’s I tested.
Yes, since they are new cells I wanted to test the capacity. I believe each started at 3.7V. The Vapcell charger charged it up to 4.2V and discharged down to 2.5V and charged back up to 4.2V for the whole test, as you can see it took around 8hour 30 minutes for each. Does the charging/discharging rate matter here, or something I don’t understand? I left that function on Auto instead of choosing a manual current.
In my experience pretty much anything under 1A for a power cell like the P45B gives you about the same results. The standard is 0.2C though, 900mA for the P45B. Doing it at 1A would be very close.
If you get the same results at a 1A manual setting then I’m thinking it’s just not very good at measuring capacity. If it’s consistent though then you can use it to track capacity loss over time or to compare different cells.
Try cycling the cell three times and see if the capacity measurement goes up. I don’t think it will make a difference…it shouldn’t that is…but it’s worth a try.
If there’s a thread for this model charger here it’s probably worth posting there to see if others have had low readings.
I have a few cells that have been sitting in storage for 1-2 years (80°F, at 3.7V)
Would you recommend “breaking” these in, and if so, how?
I should have phrased that differently, without using “breaking in”.
There can be something called “recoverable capacity loss” but it’s not much (compared to the “irrecoverable capacity loss” that happens over time, in storage or while being used) and I’ve never seen much more than a few mAh recovered.
Even some P42A’s I had in storage since 2019, and were made in 2018, only recovered about 45mAh earlier this year
There’s no way to recover/reverse any noticeable internal resistance increase that I’ve seen but perhaps that is cell dependent. I haven’t read enough about this to know for sure though.
I just use the cells normally and any recoverable capacity comes back that way. Doing a separate cycle, or cycles, just shortens the overall life of the cell with no real benefit here IMO.
Confirm that your cells are still at over 2.5V before using them though. If not, recycle and replace them as they will have been at a too-low voltage for a while and that can cause damage.
On a side note…I’ve seen some pouch LiPo’s that, IMO, seem to have skipped (to save money?) some of the formation cycling that is done after being assembled. These cells can benefit from cycling to improve their performance but you can just use them normally (gently to moderately) for a few cycles instead of wasting the limited number of cycles they have.
Ok, I was able to do the capacity test on my last fresh cell at 1000mA on the manual settings, it took nearly 17.5 hours but we got it done
Does the result look any better @Mooch? Ended with 4276mAh (the last picture) It still seems kinda low compared to what you said, 4375 and 4401
Should I try the next capacity test at 500mA since I can’t go inbetween to the 900mA recommended?
I don’t think it will make any difference but you could try. Unfortunately I think it’s just that your charger isn’t accurate. This is a verrrrry common problem with slot round cell chargers.
Recently, I got these new P45B “A3” variant for upcoming new flashlight. I couldn’t get the normal P45B “A0” locally for a long time so I got these instead.
From what I checked online, they have slightly lower capacity and slightly higher internal resistance.
I have the older A3 one back in April 2024 and compare to the new one. It’s quite different.
While these A3 variant has been out for quite sometimes, this label is updated recently on new batch and surprisingly what I got are a bit different . The one with “15.66wh” is probably newer.
I think this new label will apply to other cells in the future batch
This is all great info for me, I was looking to power my Q8 with Moli P45B, then just couldn’t find enough accurate info so went for the 40T button tops from Nkon to be sure. No wonder things are so confusing if the protrusion is varying batch to batch.
Most cells we buy will soon have labels similar to this. It’s part of the requirements for cells that have passed the China Compulsory Certification (CCC) testing (a very good thing for the companies who don’t fake the results).
The min capacity, Wh, “CCC”, and polarity needs to be marked on the cell at a minimum IIRC with other things okay to mark on the box.
Howdy @Mooch and everyone else here, hope you can help me settle a question re: the P45B capacity.
I got 3 of them recently and after a couple of gentle uses, did a serious capacity test in my SkyRC MC3000 and I’m seeing very disappointing figures of 4210-4241 mAh.
This measurement was done with the parameters that I could gleam from the P45B datasheet:
CC charge at 2A until reaching 4.20V, then CV until current<0.05A;
CC discharge at 1A until reaching 2.50V, then full stop – that is, no CV phase at the end of the discharge by progressively reducing current while keeping voltage at 2.50V until reaching some certain mAh value.
It’s that last part (no CV phase at the end of discharge) that’s giving me pause; so I ask y’all: is that the way it’s supposed to be?
TIA!
PS: here’s the the written part of the label on one of them:
You can find out how to read the manufacturing date on this page: Molicel INR-21700-P45B - Lithium ion Battery Manufacturer and Supplier in China-DNK Power
It looks like it was made May 10, 2024, if I’m not mistaken.
Earlier batches doesn’t have this “CCC” at all from what I have seen some videos. There was an extensive testing video here:
It perform about the same or slightly different.
I’m glad they did add more labels.
Thanks for the info and the link! Pasting it here in case it helps someone else looking for it (or that page eventually goes away):
Cell Date Code: YMDDSS
Y: indicates calendar year, 9=2009, A=2010, B=2011, C=2012, D=2013,
E=2014, F=2015, G=2016, H=2017, I=2018 etc.
M: indicates calendar month, 1~9, 10=A, 11=B, 12=C
AD: indicates calendar date of a month, 01~31
AS: indicates the sequence number in a day, 01, 02, etc
Agreed, I just followed the instructions above (took me some time to figure the 2nd ‘digit’ on mine is actually the letter “O” and not a zero… 
) and despite the spacing being different, I decoded it to 2024-05-10, and it being part of “sequence” (production batch?) 02.
So not too old, considering I purchased it last November (ie about 6 months after manufacture), and when I received them, they were all at exactly 3.49V of charge – so probably not long enough nor deep enough under 50% SOC to be damaged, right? right? 
It took me a bit to figure it out too because you have to disregard the first four numbers.
Thanks for the link. I wish I wasn’t such an uncultured bastard and could understand Russian… :-/ but from the screenshots (fortunately in English) I see the discharge being mentioned just as “Constant current (…) to 2.5V” over and over (eg, at 2m45s, 3m34s, 5m00s, etc).
OTOH at 9m19s, the video shows a discharge graph with a totally straight current curve at 10A and voltage stopping suddenly at ~2.5V, so I guess at least this reviewer did not do any ‘terminating’ CV phase at the end of the discharge. Curiously, he measured a capacity of just ~4.3Ah, which is significantly lower than @Mooch’s at ~4.5Ah and much closer to my own measures of ~4.2Ah. Perhaps the lower capacity I found still stands as the reviewer in the video was testing at 10A, and I tested at 1A… too bad @Mooch didn’t state at which current he test-discharged them.
At 9m47s we can see a screen showing the same discharge graph but at a constant 2A (still double the 1A I used) but obtaining significantly higher capacity at ~4.4Ah, so who knows, with a discharge of 1A he could well reach ~4.5A like Mooch did.
As a side note for anyone else reading this, I found the table at 5m50s quite interesting: it shows the self-discharge rate and internal resistance change after 28 days of storage, both at 23C and 60C, first time I see this kind of info for these batteries.