Cordless telephone set consists of a base station, which is connected to fixed telephone line, it also has a wireless handset that is powered by a battery and gets charged when this handset is placed in its cradle on the base station. Batteries of the cordless phone are made up of Nickel Cadmium, Nickel Metal Hydride or Lithium Ion, each having its own unique characteristics.

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There are several technologies being used in making batteries for modern electronic devices. They are based on different chemical principles, and they involve different elements to produce electrical energy. Some popular examples of popular battery types are Nickel Metal Hydride (NiMH), Nickel Cadmium (NiCd), Alkaline Batteries and Lithium-Ion (Li-ion) batteries.

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