VapCell M11 18350 1100mAh 9A batteries

Batteries in the relatively uncommon 18350 form factor, but with a decent discharge current.

Model on the manufacturer's website - link
This model is listed on several AliExpress pages. Here's a link to the one with the lowest price and quantity options - link, priced at $7.99 for 1 pc. and $9.99 for 2 pcs. There's also a version with a raised positive terminal.
These batteries are also available from nkon for €3.95 - link


Key specifications
Model: INR18350 1100mAh 9A
Size: 18.1*35.0mm
Nominal voltage: 3.60V
End-of-charge voltage: 4.20V
End-of-discharge voltage: 2.5V
Typical capacity: 1100mAh (0.2C discharge)
Minimum capacity: 1000mAh (0.2C discharge)
Weight: Max:26g
Internal resistance: Max:25mΩ （AC 1kHz）
Standard charge: 500mA, CCCV, 100mA cutoff
Charging time: 3 hours (standard charge)
Quick charge current: 1500mA
Max continuous discharge current: 9A

The packaging is a plastic box with the VapCell logo.


The color is blue-purple. The positive terminal is flat, but protrudes slightly. There's also a version with a button top available; the negative terminal is slightly convex as well.


The dimensions are almost exactly as specified: the length is just 0.1mm greater. They weigh 24–24.5 grams, compared with the 26g listed in the description.


I happened to notice the shape of the positive terminal. It looks as though it has been made a little larger.


A “test” cycle using a regular charger and a 0.5A discharge showed that the capacity is roughly in line with the figure given in the description.


According to the description, these batteries charge at 0.5A, with charging terminated when the current drops to 100mA. In my case, charging used the same current, but cut off at 0.05A (the standard mode for the EBC-A10H). The second cell took 2 hours and 9 minutes to charge in this mode.


The page for this model includes a screenshot of test results from the well-known lygte-info.dk website.


I tested them at discharge rates of 0.2, 0.5, 1, 2, 4, 6C, and currents of 9 and 12A.
The first battery did indeed deliver the rated 1100mAh at a discharge rate of 0.2C. Don't let the somewhat odd discharge curve at 12A put you off; I'll explain that later.


Battery temperature at discharge currents of 6.6, 9, and 12A.


The second battery delivered only 1056mAh, which is still within spec, since the minimum capacity at 0.2C is rated at 1000mAh.


Temperature at 6.6, 9, and 12A. In my opinion, 72 degrees at the maximum rated current is pretty good; even at 12A, the temperature stayed below 90 degrees.


Now for an explanation of the first battery's test results. I simply overheated it. This happened because, during the 6.6A test, I accidentally set the current to 16.6A (the test was originally run with an EBC-A20 load) and only noticed when I came to measure the temperature and saw 122 degrees!
Unfortunately, the discharge graph wasn't saved because the power went out throughout the house just 5 seconds after I took the thermal image.

At least I can now say that the battery survived that test too. Unfortunately, it affected its performance, so in this case, only the second battery's test results at 6.6A and above are valid.


This is what the batteries looked like after all my abuse. I heated the second one later to see how the heat-shrink tubing would hold up. Just like with other brands, it started to melt at around 100–105 degrees.


The first battery's test results got noticeably worse. The overheating also affected its internal resistance; more precisely, the test results worsened because the internal resistance changed.
Measurements when received, after “conditioning,” and after all the tests.


These batteries are rated for a maximum continuous current of 9A, though they can also handle up to 12A. But the accidental 16.6A test clearly affected their “well-being.” To be fair, though, nearly a 2× overload is quite significant.
I've reviewed plenty of genuine Samsung batteries, Murata and so on, and even those ran hotter at the currents specified by the manufacturer, which speaks to their honest ratings.

I recommend them. And to save money, you can order via the first link in the review: it offers batteries with minor cosmetic defects, but the same performance quality.