18650 is an industry saying that refers to a cylindrical battery with a diameter of 18mm and a length of 65mm. The production factories are mainly Sanyo, Panasonic, Samsung, and Sony. There were also some manufacturers in my country that produced 18650, but the reputation and influence are not as big as the three mentioned above. Because Panasonic won over Sanyo, it actually became the production factory of 18650 in the world.
18650 capacity：
Individually, there are 2200mAh, 2400mAh, and 2600mAh capacity standards.According to industry sources, the original 18650 has achieved a single-cell capacity of 3400mAh.If the mobile power supply uses 18650 as the battery cell, it is basically connected to the above standards.
18650 packaging：
The 18650 is individually packaged in a steel shell, that is, the lithium ions of the 18650 are liquid, just like a cup filled with water, similar to this understanding.Therefore, the 18650 can only be cylindrical. If you see a thick and large mobile power supply when you buy a mobile power supply, it is basically a 18650 battery cell.
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