What is the voltage range of 18650 lithium battery?

In terms of types, lithium batteries include lithium-ion batteries, lithium iron phosphate batteries, ternary lithium batteries, polymer lithium batteries, nickel-cobalt lithium and many other types.

In addition to polymer lithium batteries, ternary lithium and lithium iron phosphate are widely used in the market. As far as lithium batteries are concerned, in the power field and energy storage field (the consumer field is polymer lithium battery), the battery cell is 18650 battery, with a diameter of 18mm and a height of 65mm.

For the analysis of the corresponding relationship between the open circuit voltage and battery capacity of lithium-ion batteries, a table is given first: as follows, the percentage is the remaining capacity of the battery, and the right side is the open circuit voltage (OCV) of the corresponding battery.

100%----4.20V

90%-----4.06V

80%-----3.98V

70%-----3.92V

60%-----3.87V

50%-----3.82V

40%-----3.79V

30%-----3.77V

20%-----3.74V

10%-----3.68V

5%------3.45V

0%------3.00V

But lithium-ion batteries have a useful feature for fuel gauging, that is, during discharge, the battery voltage gradually decreases with the passage of charge, and has a considerable slope. This provides us with another approximate approach to electricity metering. The method of taking the battery voltage. Just like measuring the water level in the tank, you can roughly estimate the amount of water remaining. But actually the voltage of the battery is much more complicated than the level measurement of the calm water inside the tank.

Common 18650 batteries are divided into lithium-ion batteries and lithium iron phosphate batteries. The voltage of lithium ion battery is 3.7v nominal voltage, the charging cut-off voltage is 4.2v, the nominal voltage of lithium iron phosphate battery is 3.2V, the charging cut-off voltage is 3.6v, the capacity is usually 1200mAh-3350mAh, the common capacity is 2200mAh-2600mAh .