Lithium Polymer batteries (LiPo) offer several advantages. It has a greater energy density in terms of weight than Lithium Ion. In very thin cells (under 5 mm) LiPo also provides higher volumetric energy density. Additionally, there is more flexibility in cell sizes and shape with LiPo and a wider margin of safety, with superior stability in over-voltage and high-temperature conditions.
To date, most LiPo applications are for widely used consumer items like cell phones, MP3 players and many Bluetooth enabled devices where low weight and small size are essential.