At last, my order from Vapcell has finally arrived. As promised before, I report my observations here:
Order date: March 27, 2021
Delivery date: June 17, 2021
Total order processing time: 82 days
Routing via Meest Group / Hermes: Guangzhou, CN – Hong Kong, CN – Istanbul, TK – Amsterdam, NL – Berlin, DE
Scope of delivery:
6x Vapcell K64 6400mAh 26650
4x Vapcell S30 3000mAh 18650
2x Vapcell F14 1400mAh 18350
2x Vapcell M11 1100mAh 18350
Observations:
Packaging was alright. All batteries came in those black Vapcell pouches (2 pcs per zip bag) or inside a plastic case (18350 cells).
Battery type |
K64 |
S30 |
F14 |
M11 |
Voltage #1 |
0.25V |
3.61V |
3.88V |
3.87V |
Voltage #2 |
0.26V |
3.61V |
3.89V |
3.99V |
Voltage #3 |
0.26V |
3.62V |
|
|
Voltage #4 |
0.16V |
3.61V |
|
|
Voltage #5 |
3.80V |
|
|
|
Voltage #6 |
3.73V |
|
|
|
AC 1kHz impedance (measured via SM8124A) |
11.2mOhm - 11.8mOhm* |
10.2mOhm - 11.2mOhm** |
52.7mOhm - 53.6mOhm |
21.3mOhm - 21.9mOhm |
* Surprisingly, the overdischarged state of the K64 did not affect the battery's internal impedance. The readings were more or less consistent regardless of its actual voltage.
** The general impedance was consistent at 10.2mOhm but the button top adds approx. 1mOhm, when the 4-wire probe measured from the button.
Verdict for K64
4 of 6 K64 batteries are dead. I will not even think about charging them up. I notice a substantial voltage variation between cell #5 and cell #6. It will probably take ongoing surveillance of self-discharging for these two cells to make sure if these are safe to use. High voltage variation seems not a good sign, though. Shrink wraps are more or less attached in a proper manner. However, they could be attached more precise, see pictures below. Batteries are clean and show no signs of corrosion or wear.
Verdict for S30
All 4 batteries show normal parameters both for voltage and impedance. All voltages are more or less consistent. I did not measure very accurately for more than two digit counts. Shrink wraps could be made more accurate and are not attached in a good way. There is a high risk that the shrink wrap will fall apart during heavy use. I found hairs and greasy debris on the outer shrink. One cell of those 4 shows signs of damage to the outer hull on the negative pole (rust-brown hole in the steel). I cannot judge how safe it is to use for long-term use in a flashlight were springs will cause wear and tear to that area.
Verdict for F14
Both batteries show normal parameters both for voltage. Impedance (approx. 53mOhm) looks rather high for an unprotected battery but it might be alright for a high capacity cell. Shrink wraps are well-attached and clean. No signs of corrosion or dirt.
Verdict for M11
There is a significant voltage variation between cell #1 and cell #2. 3.99V is definitely way too high for storing batteries. Since the other battery shows a more or less good storage voltage I suspect quality fluctuations on this cell. To be fair, it will take a longer observation to assess any high self-discharging. Shrink wraps are well-attached and clean. No signs of corrosion or dirt.