LithiumPolymer

Lithiumpolymer, commonly called lithium polymer or Li-polymer, is a type of rechargeable battery that uses a polymer electrolyte instead of a conventional liquid electrolyte. The electrolyte can be a solid polymer or a gel polymer, in which lithium salts are dissolved within a polymer host. This arrangement allows the use of flexible, lightweight packaging such as a pouch instead of a rigid metal can, enabling various cell shapes.

Most Li-polymer cells employ the same lithium intercalation chemistry as other lithium-ion batteries, with graphite anodes and layered oxide cathodes. The nominal cell voltage is typically around 3.7 volts per cell, and energy density generally falls in the same range as other Li-ion chemistries, roughly 100–200 Wh/kg depending on materials and design. The polymer electrolyte can improve leakage resistance and enable thinner, lighter formats, which is advantageous for compact electronic devices and lightweight RC models.

Advantages include packaging flexibility, reduced risk of electrolyte leakage, and potential weight savings. Li-polymer cells can be manufactured in thin or custom shapes to fit specific devices, contributing to design versatility.

Disadvantages involve sensitivity to mechanical damage, once punctured or deformed cells can pose safety risks, and the need for careful thermal management and appropriate charging equipment. They also tend to be more expensive to manufacture than some liquid-electrolyte lithium-ion cells, and performance can degrade at extreme temperatures or high discharge rates.

Applications span consumer electronics, smartphones, tablets, wearable devices, drones, and RC hobbyist power systems, where a combination of energy density and adaptable form factor is beneficial. Proper storage, charging, and handling are essential to safety and longevity.