Historically, lead-acid, nickel-cadmium (Ni-Cd), and nickel-metal hydride (Ni-MH) batteries have been the conventional choice for small-sized rechargeable batteries. In line with the recent trends toward mobile and cordless electronic equipment, rechargeable batteries are required to provide higher energy density to meet the needs of ever smaller and lighter devices. Moreover, the attention being focused on protecting the environment has resulted in demand for products that are environmentally friendly.
Features
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.