ELECTROCHEMICAL PROCESS FOR PRODUCING SNNI ALLOYS FROM IONIC LIQUIDS BASED ON CHOLINE CHLORIDE USABLE AS NANOSTRUCTURED POROUS ANODES FOR ION INTERCALATION BATTERIES

摘要

The invention relates to an electrochemical process for producing nanostructured porous anodes of SnNi alloy made of ionic liquids based on choline chloride, the anodes being used to manufacture batteries of Li/Mg-ion type with minimum impact on the environment. According to the invention, the process consists in applying a constant current, at current densities within the range of 5...20 mA/cm, with a temperature ranging between 60...80° C and a process duration of 30...60 min, in an electrolytic medium with minimum impact on the environment, based on choline chloride - ethylene glycol eutectic mixtures in a molar ratio of 1 : 2, to which 0.25 - 1 M NiCl.6HO and 0.25 - 2 M SnCl.2HO are added, to result in a cathode deposit of SnNi alloy with a cathodic efficiency of 95...97%, which, after application of a controlled anodic attack in 0.1 M HCl, at a current density of 10 ± 5 mA/cmfor 2...5 min, forms a porous nanostructure, the porous anodes growing in thickness simultaneously with the current density increase and the process duration, and the composition thereof ranges between 60...68% Sn and 32...40% Ni, the percentage being expressed by weight, with the pore diameter ranging between 200...250 nm, which provides the Mg ion insertion/disinsertion, while preserving the deposit integrity.