Safe
Its status is more stable even in over-charge and there is less possibility of the electrolyte to leaking.
Thinner
Flexible packaging and the shape of the battery allows for customisation
Lighter
The polymer electrolyte means the soft aluminum foil packaging can be used as an alternative to other metal materials.
Larger capacity
Like other lithium batteries, the Li-polymer battery has a large capacity for a single cell and also a long cycle life.