Power

Mobile phones can obtain power generally from batteries. Batteries can be recharged from mains power, a USB port or a cigarette lighter port in a automobile. The most common form of cell phone batteries were Nickel Metal Hydride. These types of batteries are ideal for their size and weight, but they seem to go dead first if the user does not let them run down all the way before charging them again (this is called 'memory effect'). The other common type of batteries used in Cell Phones are Lithium-Ion, which are lighter and do not have the memory effect that Nickel Metal Hydride batteries do.