*Investigation of Boron-Based Ionic Liquids for Energy Applications DOI: http://dx.doi.org/10.5772/intechopen.105970*

As shown in **Figure 1**, designing BBILs for different EAs is often done by tailoring component ions with functional groups. The ion structure (like a positive-negative charge, small-large) greatly affects the physicochemical properties of ILs and, ergo, also affects the application to be used. For example, adding hydrophobic alkyl chains to its component ions causes changes in the chemical properties of ILs, increasing the viscosity and melting temperature that are undesirable in electrochemical devices. Therefore, it is necessary to achieve functionalization without destroying the basic properties of BBILs.
