Lithium Polymer Battery

In the year 2018, rechargeable batteries have become a part of almost every electronic device in the world. Cell phones use them; tablets use them, fans, wrist watches, and some televisions also use them. 

Lithium is a chemical element that is made with atomic number 3, and it is an alkali metal (for people inclined to the study of chemistry). Under standard conditions, it is the lightest metal known to man, and this makes it very useful in industries looking to reduce the weight of their products.

A polymer is a large molecule formed by repeating units of the same compound.

A battery is a device that contains an electrical charge I itself and can release this charge to another system such as a television, remote control or a radio set. 

A lithium polymer battery can also be called a lithium-ion polymer battery which is usually abbreviated as “LiPo,” LIP,” “Li-poly,” ”lithium-poly”  and others), is a rechargeable battery made by using lithium-ion technology with a polymer electrolyte rather than a liquid one. High conductivity gel polymers form this electrolyte.

Lithium polymer battery cells were developed from lithium-ion and lithium-metal cells which underwent extensive research during the 1980s. Sony was the first brand to create a commercial cylindrical Li-ion cell in 1991, and after that, other packaging forms evolved, including the pouch format now also called "LiPo."

Lithium polymer batteries work on the principle of “intercalation” (the reversible inclusion or insertion of a molecule (or ion) into materials with layered structures.) and “de-intercalation” of lithium ions with a positive electrode material alongside a negative electrode material, with the liquid electrolyte providing a conductive medium. To prevent the electrodes from touching each other directly a microporous (pores can only be seen with the use of a microscope) separator is in between which allows only the ions and not the electrode particles to migrate from one side to the other.

The voltage of a Lithium polymer battery cell depends on its chemistry and varies from about 2.7-3.0 V (discharged) to about 4.20 V (fully charged), for cells based on lithium-metal-oxides (such as LiCoO2), and around 1.8-2.0 V (discharged) to 3.6-3.8 V (charged) for those based on lithium-iron-phosphate (LiFePO4). 

The exact voltage ratings are usually specified in product data sheets, and the cells are usually protected by the electronic circuit that stops them from overcharging or discharge under use. For rechargeable lithium ion polymer battery packs with cells connected in series, a specialized charger may monitor the charge on a per-cell basis so that all cells are brought to the same state of charge (SOC).

Lithium polymer battery cells provide manufacturers with great advantages. Some of these advantages include the fact that they can easily produce batteries of almost any desired shape. For example, space and weight requirements of mobile phones and notebook computers can be completely satisfied.