Overview

Alkali-Ion Batteries

Currently, lithium-ion batteries (LiBs) are popular in the emerging markets of portable electronics and electric vehicles. however, the increasing demand for lithium associated with these new and large-scale applications is expected to skyrocket the price of lithium, affecting reserves as well, as it is not a naturally abundant element. One way to decrease cost of LIBs is reducing or completely eliminating elements that have low abundance in the crust of the earth and are expensive, such as Li, Ni and Co while maintaining or increasing their performance. 

In the past decade, the interest in other alkali metal (Na and K) ion batteries have grown. There are different battery chemistries offering different advantages, of which Li-ion, Na-ion, and K-ion batteries are competing for the title of being battery of choice for grid scale energy storage. These chemistries are at different levels in their readiness to be commercialized and fully implemented as energy storage for the grid. 

For the development of advanced alkali-ion batteries, a key innovation proposed by our group is the synthesis of high energy and high-safety electrode materials. Currently, our group concentrate to develop the high safety olivine-type LiFe1-xMxPO4 (M = transition metals) cathode, high voltage Prussian Blue cathode, high capacity layered-type NaxMO2 cathode and high voltage layered-type KxMO2 cathode materials.

Alkali-Metal Batteries

Rechargeable batteries comprising electrochemical cells with alkali metal (Li, Na and K) anode are promising alternatives to conventional lithium-ion batteries due to high specific capacity and the low standard redox potentials of the alkali metals.

However, the uncontrollable (Li, Na and K) dendrite growth and the resulting unstable interfaces during repeated (Li, Na and K) plating / stripping lead to severe safety issues and a short cycle life, which are aggravated especially at a high current density.

For the development of advanced alkali-metal batteries, a key innovation proposed by our group is the modulation of electrolyte solution and/or implantation of protective layer on alkali metal surface. Currently, our group concentrate to develop the anode-free lithium-metal batteries using liquid and/or solid electrolyte.

Lithium-Sulfur Batteries

Lithium-sulfur (Li–S) batteries are becoming attractive due to the abundance of elemental sulfur and its environmental compatibility. In addition, sulfur undergoes a two electron redox reaction with lithium and offers an extremely high theoretical specific capacity of 1675 mAh/g and a high energy density of 2600 Wh/kg. 

Despite these advantages, several issues have hampered the practical use of Li–S batteries. For example, the insulating character of sulfur (S8) and lithium sulfide (Li2S) impede the full electrochemical utilization of sulfur. Moreover, the dissolution of lithium polysulfide intermediates in the electrolyte triggers undesirable shuttle reactions. 

For the development of advanced Li–S batteries, a key innovation proposed by our group is the synthesis of the novel electrode and electrolyte materials that can maximize the electrochemical initialization of S8 under practical constraints.