How to buy 18650 batteries?

Question

Batteries

I have a box for 18650 batteries with a charge controller. It needs batteries. There are ali / ibey, there are a lot of them. Is there some kind of secret phrase to get batteries in capacity close to the inscription on the case? I have 4 batteries from 4000 to 6200 mAh and none of them charge the phone with 2000 mAh by more than 20% =(

Answer 1

The secret phrase, of course, is: "remove the noodles from the ears."
For example, we go to the website of Panasonic, a well-known and recognized manufacturer of batteries, we find a catalog of cylindrical lithium batteries there and look at what nominal typical capacities are there for everything that is
18650 : - 2900 mAh That is, there is no question of any 4000 or 6200 mAh at all. And the fact that Uncle Lee can write at least 10,000 on the battery case is no doubt.
You can deal with batteries of unknown origin and overrated capacity only if you have a "smart" charger that will also tell you the whole truth about them.

Answer 2

Today there are already 3600mAh and according to rumors even 3800mAh.
Anything 4000mAh and above is fake and most often has 500mAh