The development of non-aqueous electrolyte chemistries for aluminium (Al) battery systems has recently received renewed attention to address some of the challenges associated with lithium-ion batteries. Of particular importance in this development is the electrolyte, which governs the battery chemistry. Chloroaluminate room temperature ionic liquid (RTIL) electrolytes made by mixing Lewis acidic aluminium chloride (AlCl3) salt with a (often chloride-containing) Lewis basic salt e.g. 1-ethyl-3-methylimidazolium chloride (EMIM-Cl), 1-butyl-3-methylimidazolium chloride (BMIM-Cl), and 1-butyl-1-methylpyrrolidinium chloride (BMP-Cl) have been studied. These tuneable electrolytes provide good thermal stability, good ionic conductivity, and a wide polarisable potential window. While these traits are advantageous the Lewis basic salt precursors are often very costly, challenging to synthesise and in some instances can be toxic. Recently, ionic liquid analogues (ILA) that are made from abundant, inexpensive and often non-toxic materials have begun to be explored. To date the two most common Lewis basic salts examined have been urea and acetamide (both contain oxygen functionality) but their rheological properties need to be improved to complete with the RTIL-based electrolytes.Our group has recently examined a range of different chloroaluminate ILA electrolytes, and we have identified a class of Lewis base salt precursors that show promise over urea, acetamide and BMP-Cl based electrolytes. Specifically, –idinium chloride salts with nitrogen functionality (i.e. guanidinium chloride [Guan-Cl], acetamidinium chloride [Acet-Cl], and formamidinium chloride [Form-Cl]) display reversible electrochemical plating/stripping of Al, good ionic conductivities (10 – 14 mS cm-1), and viscosities (50 – 80 cP). The choice of Lewis base salt can have a profound impact on not only the electrochemical performance but also the chemical and rheological properties of the electrolyte.As such, this contribution will highlight our efforts in studying the chemical functionality of the Lewis base by changing from oxygen-, nitrogen- and sulphur-based ligands. We will also examine the compositional differences and determine the liquidus range by systematically varying the molar ratios of the Lewis acid : Lewis base. We will report how this affects the chemical speciation of the electrolyte, the ionic conductivity, and the electrolyte viscosity. This will help us identify an optimal electrolyte composition for testing in a coin cell configuration. Temperature-dependent electrochemical performance of these electrolytes will be evaluated using cyclic voltammetry (CV), electrochemical quartz crystal microbalance (EQCM), and electrochemical impedance spectroscopy (EIS). The chemical speciation of Al in the different electrolytes will be analysed using 27Al NMR and Raman spectroscopy. This will help identify if Al2Cl7 -, AlCl4 - or other ionic species are responsible for their behaviour. Overall, this work will provide a deeper, fundamental understanding of these novel electrolytes and their application in aluminium-based batteries.