Telecom battery is a type of lithium-ion battery. They’re used as a power source for telecom devices. Lithium-ion batteries contain chemicals like lithium-ion, lithium polymer, lithium metal polymer, and other kinds of lithium derivatives.

A power supply is an electrical device that supplies electric power to an electrical load. The primary function of a power supply is to convert electric current from a source to the correct voltage, current, and frequency to power the load. As a result, power supplies are sometimes referred to as electric power converters.