Lithium-ion Batteries

Lithium "the white gold"

Lithium was discovered in Sweden in 1817 by Johan Arfwedson. The name is derived from the Ancient Greek lithos meaning "stone. In pure form, it is a soft shiny gray material that oxidizes rapidly in air.

Lithium was first produced on a large scale in 1923. Today, more than 70 percent of the world's lithium supply comes from the "lithium triangle": the salt flats in southern Bolivia, northern Chile and northwestern Argentina. Bolivia is home to the world's largest salt flats, Salar de Uyuni.

Lithium is the lightest of all metals with the greatest energy density. The nominal voltage of a single cell can range from 3.6 to 3.8 volts depending on the anode used. The Li-ion battery can store significantly more energy per kilogram of battery than a NiMH battery (140Wh/kg energy density).

Li-ion batteries

Alessandro Volta was the first with the invention of the battery. A battery is a type of device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. Each cell contains a positive terminal or cathode and a negative terminal or anode. Electrolytes allow ions to move between the electrodes and terminals, allowing current to flow from the battery to perform work.

After chemist Stanley Whittingham of Exxon developed the concept of lithium-ion batteries in the 1970s, Sony and Asahi Kasei created the first commercial product in 1991. The first batteries were used for consumer electronics. Now, building on the success of these li-ion batteries, many companies are developing larger sized cells for use in energy storage applications that can even provide ancillary services on the power grid.

Advances in technology and materials have significantly increased the reliability, output and density of modern battery systems. The associated costs have also been dramatically reduced. Continued innovation has created new technologies, such as electrochemical capacitors that can be charged and discharged simultaneously and instantaneously.

One disadvantage of the Li-ion battery is that it can break down when deep-discharged. Therefore, a Li-ion battery or battery pack always needs a BMS (Battery Management system). This system controls the voltage to prevent deep discharge, overcharging and excessive power consumption. If a Li-ion battery is not used, it is best to keep it cool in a half charged state.

Lithium-ion batteries are currently one of the most popular battery types.

Advantages:

- High energy density

- Compact shape

- No maintenance needed

- Low self-discharge

- No memory effect

- More environmentally friendly than other batteries.

- Long life time