Rechargeable telephone batteries power both home and mobile phones, and allow users to communicate without the limits of traditional power cords. Not all phone batteries are the same, however, as the chemical composition of a battery can affect its performance. Nickel cadmium (NiCd) and nickel metal hydride (NiMH) batteries have been available for decades and are relatively inexpensive, while lithium ion (Li-Ion) and lithium polymer (Li-Poly) batteries are newer and offer superior performance.
Nickel cadmium rechargeable telephone batteries were popular when portable phones first became available, but suffer from a “memory” problem that lowers the usable battery capacity over time. NiCd batteries use a combination of nickel oxide hydroxide and cadmium to generate a charge. While this chemical mixture allows NiCd batteries to be recharged quickly, the cadmium metal is both heavy and toxic. Due to these drawbacks, nickel cadmium batteries are not often used in new phones.
The nickel metal hydride types of phone batteries have similar characteristics as older NiCd varieties, but do not contain harmful cadmium metals. In addition to being safe for the environment, NiMH batteries deliver between 20 percent and 30 percent more power than their nickel cadmium counterparts. Nickel metal hydride phone batteries do suffer from a memory problem, but users can minimize this limitation by completely discharging a NiMH battery pack after every ten charge cycles.
Lithium ion rechargeable telephone batteries are found in a wide range of modern devices, including both home and cellular phones. Li-ion cells have very few drawbacks compared to earlier types of batteries. Unlike NiCd or NiMH battery packs, lithium ion models are lightweight and are not prone to a memory limitation. Li-ion battery cells are able to deliver consistent power over a long time frame, which makes them particularly useful for mobile phones. The primary disadvantage of this battery is the cost, which can be significantly higher than older battery types.
The lithium polymer variety of telephone battery is the most modern and advanced of the four common types. The design of a li-poly battery allows it to function properly without an outer casing or container. This feature, along with the extremely lightweight chemical mixture, makes lithium polymer cells particularly useful for slim cell phones. As with lithium ion cells, li-poly batteries do not have a memory problem and can be recharged at any time. Lithium polymer types of rechargeable telephone batteries are more expensive then other kinds of power cells.
