Here is a little story about Chinese battery vendor that seems to underestimate the importance of quality control bad time. I wanted to share this with everyone since they won’t answer to me and we can’t get these problems solved and QA fixed (first they told to refund 1/3 and it was not even 1/3 really, now that we have lot more problems with these they won’t answer to any questions). I also want to warn because they sell high current batteries for Vaping. If they are such bad quality batteries also (with that QA, i wouldn’t be suprised…), i’m afaraid something bad could happen someday. So please, if you use Efan battery, read this and check that yours battery is ok.
I have bought now few times these Efan/Eizfan batteries from China, mostly because price is very competitive and they seems to use really genuine Panasonic/Sanyo cells. Unfortunately all the times there has been something wrong with orders. Usually it has been just something with specifications, like PCB should handle much more constant current that it does, or low voltage cut-off was not 3.0V as i was told but it was 2.5V (that is ok though, it is just that why you promise different).
Well, these wasn’t that bad problems, i can leave with those specs now that i know how they really perform.
In first order (at the end of 2012) i got batteries that could handle only ~3A constant current, even though i was told that they perform just like Keeppower, in that time it was something like ~6-7A.
In second order button top versions did handle ~5-6A but flat top still only ~3A. So different protection in flat top and button top for some reason.
I got one battery in that order which was DOA (It was PCB faulty, one defective battery, not that bad) and one battery did look very strange. Picture here:
Well, i had to take off that wrap to see what has happened. It was rusty, i was very amazed.
If i remember correct, they just said they can send me replacement in next order. I accepted that. Meantime i was just thinking, how this can happen, where is QA.
Third order was quite ok, i don’t remember any problems except that lenght was now 1mm more than last order. I was happy, at last we got quality batteries with decent specifications.
Fourth order was totally disaster. After waiting about week, i got information that batteries are ready to ship and i got image about those. They were without any label, even we agreed that there must be labels with real specs, CE and RoHS etc. I was really confused why these won’t have labels and i didn’t agree that. They told me they will add labels. Well that was good, no problem then.
Finally when i got these, problems start straight.
First of all, they were so thick that they couldn’t fit to any Convoy flashlights, so something has now changed since old ones i had no such problem. First battery i looked did show some scratch under wrap. Well, i thought i have to look what it is and is there explanation for this thickness. Well, this time there was Sanyo wrap under, old batteries were without original wrap, only clapton tape, so it won’t be that thick. But also there was scratch on Sanyo wrap and it was quite dirty, picture here:
I asked about this and they said it is ok because it is under that black wrap. I was confused about that answer, no this is not ok, are they used or how that can look like this. They just say, it is ok, no problem…
Well, then i got one battery that was ~3,0V but won’t charge. Again, i take wrap off to see what has happened. And now i was very confused, how is this possible… Picture here:
There was no wrap at all this time, neither clapton tape, so it was shorted badly. How can anyone send battery like this to customer… Again very bad QA.
Here is third battery that was scratched under that black wrap, i don’t understand how in new batteries there is such scratches:
Looks like there is no any QA at all.
Here is pictures about 26650 batteries:
There is sad thing that they are quite thick also and that minus side has this very sharp point. Same problem is with 18650 (about 1/2 of those). It won’t last long that is sure. And also two of these got scratch on wrap out of box. One of these came 0V with PCB and 0,4V without PCB. Don’t know what has happened with this one, but definitely not good thing. But it did perform better than cell which was in correct storage voltage, as we can see on next chart. Very strange.
Then little bit measurements. Here is test with and with out PCB:s and compared to Keeppower 3500mAh. As we can see, PCB used in these Efan version is not that good. Voltage drop is huge IMO. Also we can see that Efan 5500mAh are not even close that 5500mAh. At 1A discharge it was about 4400mAh.
Efan and Keeppower 18650 3500mAh
Here is also thermal images at the end of test, Keeppower stays little bit cooler here.
Keeppower
Efan
This is my opinion: do not buy these if you are looking quality batteries and well handled after sale support. I prefer now on Keeppower and maybe i will test these Kaidomain versions also which looks pretty good in specs.
I bought these from:
Shenzhen Yifang Technology Co, LTD
Websites:
www.sz-worldsales.com
www.yifangpower.com
Contact person Eileen
It would be nice to share experiences with other users, has anyone bought these?