Beyond Li-ion: development of reversible non-aqueous metal-air batteries

Abstract

Electrochemical energy storage has revolutionized portable electronic devices, where batteries has played a pivotal role on the cell phone and laptop capabilities and also on the development and commercialization of electric vehicles. However, Li-ion batteries used today are still very similar to those developed three decades ago, seeing only small improvements on cell packing and engineering of electrodes, separators and electrolytes. Batteries will be more present in our lives, as electric vehicle popularizes, and decentralized smart grids emerges. For that, batteries need to be cheaper, store more energy and recharge faster. Metal-Air batteries are an incipient type of battery that can be disruptive if a reversible and long-lasting system is achieved. For instance, Li-Air battery is the only type today that can be competitive with petrol in volumetric energy. But those batteries still suffer from low energy efficiency, low-capacity retention, and short cycle life. Improvements need to be done in all components: the negative electrode, ie. the metal that will go under plating/stripping, the positive electrode, where the oxygen reactions occur, and the electrolyte that has a huge impact on the oxygen electrochemistry. This project will investigate the three components utilizing in operando and in situ techniques alongside the battery charge-discharge. For instance, the solid electrolyte interface formation on the metal surface will be analyzed with Raman and Infrared spectroscopy. Moreover, novel carbon materials with various textural properties will be produced for the positive electrode, the products of oxygen reactions will be identified by the same techniques in addition to differential electrochemical mass spectroscopy and X-ray tomography. Solvent and salts in electrolyte role will be investigated using the same techniques. (AU)