High-performance flexible Al-air batteries with liquid alloy-activated anode

A high-performance flexible Al-air battery with liquid alloy-activated anode system is developed for wearable electronics. By constructing activation interface composed of Ga–In liquid particles (GILPs) on the Al anode, the electrochemical performance of the flexible Al-air battery is enhanced. This work validated that GILPs can not only serve as active sites for the oxidation reaction of Al atoms to avoid the generation of passivation film, but also can further expand the active Al range and improve overall performance of the battery. These GILPs also exhibit satisfying electrical conductivity to reduce the mechanical loss of the Al anode during discharge, resulting in a high energy utilization of the battery. The Al-air battery with 150 μg cm−2 GILPs displays remarkable capacities of 2345 mA h g−1 at the current density of 1 mA cm−2, 1.6 times higher than that of Al-air battery without GILPs loading. Amplification experiment of Al anodes’ thickness and area are performed. The results indicate that the lifetime of battery can be extended by scaling up thickness of Al anode, and overall battery amplification efficiency is greater than 93.5%. This study opens up a prospect for the application of Al-air batteries in the field of flexible wearable power supply devices.