Lithium Batteries
Powering our cell phones, iPods, and laptops, lithium-ion batteries make our electronic technology portable.
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If you are viewing this webpage from a laptop computer, it is probably powered by a lithium-ion battery.
Lithium-ion batteries are lightweight and relatively low cost, which make them ideal for applications requiring portability. Rechargeable lithium-ion batteries also have a considerable advantage over nickel-based batteries because the lithium batteries do not suffer from the memory effect. When nickel-cadmium batteries are discharged only 25 percent before they are recharged the batteries will adjust to that capacity and subsequently only discharge down to that new standard. This ‘memory loss’ drastically reduces the battery’s capacity and utility. In contrast, lithium batteries, which lack the memory effect, may be recharged regardless of how much their current has been depleted without affecting their future performance.
Slightly different technologies have led to several varieties of lithium-based batteries. Primary batteries with lithium anodes are disposable. This type of battery retains its original charge for months, which is an important advantage when batteries must be stored for extended periods of time between uses. Secondary batteries using lithium ions rather than metallic lithium are rechargeable, but these batteries experience higher self-discharge rates than primary batteries, so rechargeable batteries that are stored will lose their charge over time more rapidly than their disposable counterparts.
Although lithium-ion batteries can maintain their performance over hundreds of charge-discharge cycles, they have a finite lifetime of only a few years. This is why many cell phone users find that after owning their new phone for a couple of years they have to recharge their cell phone battery more frequently than when they bought it. Another disadvantage: lithium-ion batteries also degrade more quickly at high temperatures.
These are some of the trade-offs with lithium-ion batteries. But given that they are extremely lightweight and possess outstanding energy capacity, able to store twice as much electricity for their mass as nickel-metal-hydride batteries and six times as much as the lead acid batteries used for automobiles, lithium-ion batteries have become essential to modern, daily life.
For more information about lithium-ion batteries, see http://batteryuniversity.com/learn/article/is_lithium_ion_the_ideal_battery