A lithium polymer battery, or more correctly lithium-ion polymer battery (abbreviated variously as LiPo, LIP, Li-poly and others), is a rechargeable battery of lithium-ion technology in a pouch format. Unlike cylindrical and prismatic cells, LiPos come in a soft package or pouch, which makes them lighter but also less rigid.
The designation “lithium polymer” has caused confusion among battery users because it can be interpreted in two ways. Originally, “lithium polymer” represented a developing technology using a polymer electrolyte instead of the more common liquid electrolyte. The result is a “plastic” cell, which theoretically could be thin, flexible, and manufactured in different shapes, without risk of electrolyte leakage. The technology has not been fully developed and commercialized[1][2] and research is ongoing