Lithium polymer does not suffer from the same dangers as that of lithium ion. The older lithium ion design requires the lithium to be held in an organic substance and contained in a metal casing – all making for a rather volatile situation if the casing were to leak. Lithium polymer, on the other hand, stores the lithium in a solid polymer composite, which is a much more stable design than lithium ion.
Other advantages to lithium polymer include the ability for the manufacturer to shape the battery to best fit around the electronics component, rather than the lithium’s metal casing. In addition, without the requirement for the metal packaging, lithium polymer batteries can be lighter and smaller. Lithium polymer is a 20 percent improvement over lithium ion battery (of the same size) in energy density, thanks to fewer restrictions in the way the battery must be packaged.
While nearly all notebook computers on the market today use lithium, Apple started shipping lithium polymer batteries with several of its MacBooks as of late October. Lithium polymer batteries are already being widely used today in some newer models of PDAs and cell phones.
Lithium polymer won’t replace lithium ion overnight. Even though lithium ion is clearly superior to older nickel-based batteries, we still find the older rechargeable technology in many of today’s devices. Thankfully, the IEEE is already planning for new standards to ensure safer battery designs.
