In summary, we have successfully prepared the GdmTFSI and confirmed its identity and purity. The crystal structure of the salt has been solved through single crystal XRD and IR was used for further characterisation. Meanwhile, probing the IR spectra and viscosity of aqueous GdmTFSI solutions reveals that the salt can disrupt the HBN of water, reducing water reactivity and expanding the ESW. However, a limitation is the water solubility of GdmTFSI, preventing water-in-salt regimes that can trigger SEI formation to further expand the ESW. Increasing the solubility could be achieved through adapting the Gdm cation to create a slightly more disordered crystal structure that can promote water solubility, while this could reduce the chaotropic effect, the right balance between solubility and chaoticity could be found. Nevertheless, we envision the potential use for Gdm/Gdm-derived-TFSI salts as a co-salt and/or additive with alkaline-metal based salts, specifically non-TFSI salts, which lack the chaotropic functionalities. We are optimistic that this salt-design principle for aqueous batteries can undergo further development, drawing inspiration from the well-established