Stable and low-voltage-hysteresis zinc negative electrode promoting aluminum dual-ion batteries

Abstract

Compared with the widely developed positive electrodes, the research on the high stability negative electrodes is far from in-depth in nonaqueous Al batteries. In order to fundamentally solve these key problems, including Al dendrites, corrosion and pulverization, it is urgent to develop an alternative stable negative electrode. Herein, the corrosion-resistant, low-voltage-hysteresis and stable Zn is demonstrated as a promising negative electrode. Since the deposited Al particles on the Zn electrode are prior to Zn in the stripping reaction, Zn electrode can remain good structural integrality, thus presenting great cycling stability and corrosion resistance. Importantly, the results in Al-Zn symmetric cells indicate that Zn possesses the ultra-low voltage hysteresis (∼17 mV at 0.5 mA cm−2), superior cycling stability (800 cycles at 1.0 mA cm−2) and Al plating/stripping reversibility characteristics. Additionally, the Zn-graphite full battery based on Zn as negative electrode and flake graphite as positive electrode delivers stable discharge capacity of 81.1 mAh g−1 over 300 cycles. The results in this work open an effective approach for constructing corrosion-resistant, low-voltage-hysteresis and stable negative electrode, further indicating that Zn is great promising as negative electrode for Al dual-ion batteries.