what is lithium ion battery?

     A lithium-ion battery or Li-ion battery  is a type of rechargeable battery.  Lithium-ion batteries are commonly used for portable electronics and electric vehicles and are growing in popularity for military and aerospace applications.

     A prototype Li-ion battery was developed by Akira Yoshino in 1985, based on earlier research by John 

goodenough, M. Stanley Whittingham, Rachid Yazami and Koichi Mizushima during the 1970s - 1980s, and then a commercial Li-ion battery was developed by a Sony and Asahi Kasei team led by Yoshio Nishi in 1991.

     In 2019 the Nobel Prize in chemistry was given to Yoshino, Goodenough, and Whittingham "for the development of lithium ion batteries" .

     In the batteries lithium ions move from the negative electrode through an electrolyte to the positive electrode during discharge, and back when charging.  Li-ion batteries use an intercalated lithium compound as the material at the positive electrode and typically graphite at the negative electrode.

     The batteries have a high energy density, no memory effect and low self-discharge.  They can however be a safety hazard since they contain flammable electrolytes, and if damaged or incorrectly charged can lead to explosion and fires.