Lithium ion battery is a type of battery where lithium ions move from the negative to the positive electrode while discharging and back when it is charging. Lithium ion battery is also called li-ion battery. A lithium battery uses an intercalated lithium compound as one electrode material, unlike the metallic lithium used in non-rechargeable lithium batteries. This is why these batteries are very good for smartphones and other similar devices. More work is still going into enhancing the capacity of lithium ion batteries. For instance, a nickel-metal hydride battery has a self-discharge rate of about 20%, which in turn shows that the shelf life is shorter than most. There are different kinds of lithium batteries and they are mostly used for portable consumer devices such as laptops, tablets and smartphones. They are also used in many electric automobiles, in the military and in aerospace.
The development of an average Lithium ion battery pack is expected cover at least 10 major parameters. These parameters are specific power, wide temperature operating range, better safety, high specific energy, lower self-discharge, affordable cost, longer life, non-toxic, fast charging, and longer shelf life. For instance, when Lithium ion batteries were in its early stages, the cost was about $3000 per kWh, while Lead-acid batteries, on the other hand, cost just about $150 per kWh. Fortunately, with major technological improvements over the period of time and also because of multiple benefits offered by lithium ion battery pack, which is at least 150Wh/kg more than the NiMH, there have been major changes to the cost. The cost of lithium battery has considerably fallen and it now varies from $150 to $240 per kWh.