What are the differences between the types of 18650 lithium batteries?

Lithium battery standard 3.7V or 4.2V is the same. It's just that the manufacturers have labeled differently and ourselves. 3.7V refers to the platform voltage (ie, typical voltage) of the discharge during the battery, and 4.2 il is the voltage when charging is charged.

Commonly recharged 18650 lithium batteries, the voltage is bidding 3.6 or 3.7V. When it is full, it is 4.2V. This has little to do with the power (capacity). Most of them are 2200 ~ 2600mAh), and the mainstream capacity is even more standard for 3500 or 4000mAh.

It is generally believed that the vacuum voltage of the lithium battery is considered below 3.0V. It is considered that the electrical value is performed (the specific value needs to see the cavity of the battery protection board, such as as low as 2.8V and 3.2V). Most lithium batteries cannot be discharged below 3.2V, otherwise excessive discharge will damage the battery (the lithium battery on the general market is basically used with a protective board, so excessive discharge will also cause the protective board to detect that it will not not detect the detection of the protective board. To the battery, it is impossible to charge the battery).

4.2V is the highest limit voltage of the battery charging. It is generally believed that the vacuum voltage of the lithium battery to 4.2V is considered to be full. During the battery charging process, the battery voltage gradually increases to 4.2V. If the air load voltage is charged above 4.2V, it will also damage the battery, which is a special place for lithium batteries.