Using sodium tetra aryl borate analogues as a novel salt within sodium ion battery applications

Since the invention of lithium-ion battery in the latter half of the 20th century. Many metal ions have gained attention in electrochemistry as alternate metal ion battery material. This project has focused on sodium ion batteries. Ionic salts are a core component in ion batteries as these are essential parts of the electrolyte system within them as they allow for ionic conductance within the system. For sodium ion batteries to become more mainstream and commercially available new systems need to be examined and explored.

This project revolves around the usage of a sodium tetra-aryl borate salt, sodium tetrakis(3,5-dichlorophenyl) borate. This salt was selected as it offers to be a promising choice in a sodium ion battery as the weakly coordinating anion would allow for it to dissolve at room temperature conditions in many polar organic solvents with high stability and allow movement of sodium throughout the electrolyte.

The first part of this project was to synthesise a salt that is of battery grade. To ensure battery grade was to be achieved the salt had to be characterised. The physical characteristics of this salt had to be determined as to make sure it was suitable for use in a battery. Once this had been determined the secondary part of this was to use the salt in some batteries with commonly used anodes to see how well they perform compared to pre-existing systems.