Coating carbon on lithium metal oxide electrode can double battery life

Coating carbon on lithium metal oxide electrode can double battery life

Subject : Science & tech

Context : Researchers have developed a non-expensive way to coat carbon on lithium metal oxide electrodes for lithium-ion batteries. The life of the lithium-ion cells prepared using these electrode materials is expected to be doubled due to protective carbon coating.

Concept :

About Lithium Ion Battery

• Lithium-ion batteries are the most commonly used power source for electric vehicles. However, its penetration to the daily usage against gasoline-based vehicles require drastic improvement in the lifetime and cost as well as mileage per charge.
• The active components of lithium-ion batteries are cathode, anode, and electrolyte. While commercial graphite is used as anode, lithium metal oxides or lithium metal phosphates are used as a cathode in Li ion battery.
• The electrolyte is a lithium salt dissolved in organic solvents. The capacity of the lithium-ion battery determines the mileage of the electric vehicle.
• Before the capacity reduces to 80%, the number of charging cycles determines the life of the battery.

Carbon Coating Technique

• Carbon being inert to most chemicals and stable under the operating window is the best choice of coating material to improve the cyclic stability of the active materials.
• Carbon coating on the active materials can double the lifetime of the lithium-ion cells.
• However, coating carbon on lithium metal oxide is very challenging, because of the difficulty involved in coating carbon during the synthesis of lithium metal oxide material in a single step.
• The electrochemical performance of the lithium-ion cells constructed using carbon-coated NMC111 is at par with that of the commercial lithium-layered oxide cathodes.
• Superior cyclic stability of the carbon coated product with capacity retention of more than 80% after 1000 cycles of charging/discharging is demonstrated with an optimum carbon thickness matching commercial samples