Polymer lithium ion batteries is a kind of high security and stable energy, this kind of rechargeable lithium batteries because of the volume can be smaller than ordinary dry-cell batteries, so heavily used on portable products, particularly in MP3, such collocation also make products more outstandingIn the past few years, for the MP3 market, many are generally use lithium battery products, in the cutthroat MP3 market, however, some vendors in order to save costs, using lithium battery quality is not very good, so the repair rate is on the high side, even caused the lithium battery of MP3 quality than using ordinary AA/AAA batteries, love consistent criticism to the consumer, now polymer Lithium ion batteries is rich in recent years, the rise of portable power supply, Polymer lithium battery is developed on the basis of liquid lithium ion battery is the latest generation of lithium-ion batteries, small volume, high energy density, low resistance, long service life, good security features and environmental performance.