Modified Al negative electrode for stable high-capacity Al-Te batteries

Metal aluminum batteries (MABs) are considered potential large-scale energy storage devices because of their high energy density, resource abundance, low cost, safety, and environmental friendliness. Given their high electrical conductivity, high theoretical specific capacity, and high discharge potential, Te is considered a potential positive electrode material for MABs. Nonetheless, the critical issues induced by the chemical and electrochemical dissolution of tellurium and subsequent chemical precipitation on bare Al negative electrodes result in poor cycle stability and low discharge capacity of Al-Te batteries. Here an efficient TiB2-based modified layer has been proposed to address bare Al electrodes (Al/TB). Consequently, the low-voltage hysteresis and long cycle life of the Al/TB negative electrode have been achieved. In addition, the electrochemical performance of the Al-Te battery based on the Al/TB negative electrode is dramatically improved. Furthermore, the modified separator technology is introduced to match with the as-designed Al/TB negative electrode. Therefore, the record-setting long-term cycle stability of up to 500 cycles has been achieved in the Al-Te battery. The facile strategy also opens a potential route for other high-energy density battery systems, such as Al-S and Al-Se batteries.

Automated summary

Metal aluminum batteries (MABs) are potential large-scale energy storage devices. Tellurium (Te) is considered a potential positive electrode material for MABs, but its chemical dissolution and subsequent precipitation on bare Al negative electrodes cause poor cycle stability and low discharge capacity. By introducing a TiB2-based modified layer and modified separator technology, the cycling stability and electrochemical performance of the Al-Te battery have been significantly improved.