A lithium-ion polymer (LiPo) battery (also known as Li-polymer, Li-polymer, PLiON, etc.) is a rechargeable lithium-ion battery that contains a polymer electrolyte cell in the liquid electrolyte used in conventional lithium-ion batteries.

There are many LiPo chemistries available. Both use highly conductive gel polymers as electrolytes. LiPos provides higher specific energy than other lithium batteries and is often used in systems where weight is an important factor, such as mobile devices, drones and some electric vehicles.

The FAQ begins with a high-level comparison of Li-Ion and Li-Polymer batteries, and then details the six basic Li-Ion battery chemistries that are best for Li-Ion batteries. Finally, the future and possible development of aluminum-air polymer batteries and solid-state batteries are prospected.

All lithium batteries contain a barrier that separates the anode and cathode, while also allowing ions to move between the electrodes. In LiPo, the polymer separator also contains an electrolyte.

Additionally, the polymer separator can provide the added function of a "shutdown separator," which shuts down the battery if it overheats during charging or discharging. The cut-off separator is a multi-layer structure with at least one polyethylene layer, which can prevent the flow of current when the temperature rises too high, and at least one polypropylene layer as a mechanical support for the separator.

Intercalation and deintercalation of lithium ions from positive and negative electrodes. Except for the polymer separator, LiPos works on the same principle as lithium ions. However, they are packaged in a completely different way.

Lithium-ion batteries are usually housed in stainless steel or aluminum casings. The case is usually cylindrical, but can also be button-shaped or rectangular (prismatic). Housings are relatively expensive to produce and tend to limit the sizes and shapes available. But it's also sturdy and helps protect the battery from damage. The housing is sealed by a laser welding process.