18 is the cell diameter, 65 is the height, and 0 means cylinder.

Samsung 18650 battery is still good, the battery cell is brand new 2900mah gray skin, the internal resistance voltage is consistent, and can be used directly for spot welding. The batteries themselves are explosion-proof, with high safety performance, no explosion, no combustion, high temperature resistance, long cycle life, and resistance to overcharging.

We cannot buy 18650 batteries in the civilian market (such as convenience stores, supermarkets, and of course, electronic markets like Huaqiangbei’s are everywhere). The reason is very simple. 18650 batteries are not packaged. Before battery packs, they were considered industrial materials, so you couldn’t buy them in shopping malls. Since 18650 is an industrial material, there is basically no trademark or capacity mark on the packaging. Therefore, you can only rely on your own knowledge when choosing an 18650 battery. The capacity can be identified from the battery cap or the color of the battery appearance.