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Characteristics of Lithium-ion Battery

Features

Li-ion batteries use lithium cobalt oxide as the positive electrode and a highly crystallized carbon as the negative electrode. Because Li-ion batteries can provide higher energy density to meet the needs of ever smaller and lighter devices, and they have high voltage, good storage and cycle life characteristics, they are widely used for 3C application.

1. High Energy Density
The weight of a lithium ion battery is approximately one half compared to a nickel-cadmium or nickel-metal hydride battery of similar capacity. Moreover, the volume of the lithium ion battery is 40 to 50% smaller than that of a nickel-cadmium and 20 to 30% smaller than that of a nickel-metal hydride battery.

2. High Voltage
A single lithium ion cell has a voltage of 3.7V ( mean value), which is equal to either three nickel-cadmium or nickel-metal hydride cells connected in series.

3. Pollution-free
The lithium ion battery does not contain any polluting substances such as cadmium, lead, mercury, etc.

4. Non-metal Lithium
The lithium ion battery does not employ any lithium metal. It is not governed by aircraft transportation rules relating to carrying lithium batteries in passenger airplanes.

5. Long Cycle Life
Under normal conditions, the lithium ion battery has a life of more than 500 charge/discharge cycles.

6. No Memory Effect
The lithium ion battery is free from the so-called memory effect, a phenomenon seen in nickel-cadmium in which the apparent battery capacity decreases when shallow charge and discharge cycles are repeated.

7. Fast Charge Capacity
The lithium ion battery can be fully charged in 1 to 2 hours, using a constant-current / constant-voltage (CC/CV) type dedicated charger with a rated voltage of 4.2V per cell.

Curve of discharge temperature, cycle life, discharge current and charge characteristics

Discharge Curve at Various Temperature
charge: 4.2V/1CmA/2.5h,temperature: 23?
discharge: 0.2CmA/2.75V