LITHIUM BATTERIES

The (-) negative standard potential and low level molar mass of Li element, make it an ideal anode materials for batteries. These types of batteries have relatively highly specific energy, energy production divided by mass of the battery because, lithium metal and compounds containing lithium are light in comparison with some other materials used in batteries, such as Pb and Zn. Lithium batteries are commonly, but there are many types of based on different lithium compounds and reactions.

                                 The lithium rechargeable batteries, generally used in portable phones and computers mainly using Li-CoO₂(x<1) as the cathode with graphite /Lithium anode LiC₆ Lithium ions are produced at the anode during the battery discharge. The maintaining charge balance, Co(iv) is reducing to Co(iii) in the form of LiCoO₂ at the cathode. This reaction occurs during battery discharge are,

Cathode : Li-CoO₂(s) + Li⁺(sol) + e⁻→LiCoO₂ (s)

Anode : C₆Li →6C (graphite) + Li⁺(sol) +e⁻

                            The battery is rechargeable because both anode and cathode act as host for the lithium ion (Li⁺) which is can move back and forth between them when charging and discharging. These are many other lithium batteries using the different types of electrode materials, mainly d- group metal compounds that taking part in the redox reaction in a similar way to the Co. The latest generation of electric vehicles uses lithium battery technology rather than Lead (Pb) acid cells. 

                   The another popular Li battery uses thionyl Chloride ( SOCl₂). This system produces a light, and high - voltage cell with a stable energy output. The overall reaction in the battery is, 

4Li(s) +2SOCl₂(l) → 4LiCl(s) + SO₂(l)

The battery requires no additional solvent as both SO₂ and SOCl₂ are liquids at the internal battery pressure. This battery is a not rechargeable as both LiCl and Sulfur are precipitated. It's used military applications and in spacecraft. Another battery system is based on the reduction of SO₂.

2Li(s) + 2SO₂(l) → Li₂S₂O₄(s)

The above the system actually not rechargeable as solid Li₂S₂O₄ deposits on the cathode. This battery uses acetonitrile (CH₃CN) as a co-solvent and the handling of this compounds and the SO₂ present safety hazards. The batteries are hermetically sealed and not available for public. They are uses in military communication and automated external defibrillation and it's used to restore normal heart rhythm.