A research team led by Prof. CHEN Wei from the University of Science and Technology of China (USTC) designed a robust antimony (Sb)/antimony-zinc (Zn) alloy heterostructured interface to ultrahigh areal capacity and energy density of the battery without Zn dendrite formation and dissolution. A high-capacity Zn- Br2 battery using this heterostructured interface also exhibited outstanding cycling stability. This work was published in Nature Communications.
Aqueous Zn battery possesses the advantages of low cost, sustainability and high safety, which makes it a promising candidate for the next generation of large-scale energy storage. However, its industrialization is severely limited due to the uncontrollable side reactions on Zn anode, high negative to positive (N/P) ratio and low areal capacity, which shorten the cycle life and lower the energy density of the Zn battery. There is also a lack of research on the performance of Ah capacity level batteries and their application in energy storage.
The schematics and electrochemical properties of the Sb/Sb2Zn3 heterostructured interface. (Image by ZHENG Xinhua et al.)
To solve the above problems, Prof. CHEN Wei’s team designed a two-dimensional Sb/Sb2Zn3 alloy heterostructured interface to stabilize the electrodeposition and dissolution of Zn at high areal capacity. The Sb/Sb2Zn3 heterostructured interface exhibited uniform electric field distribution and strong adsorption to Zn atoms, enabling dendrite-free Zn electrodeposition/dissolution at an ultrahigh areal capacity of 200 mAh/cm2. The team then used the Sb/Sb2Zn3-heterostructured interface to fabricate an anode-free Zn-Br2 battery with a practical energy density of 62 Wh/kg. The scaled-up Zn-Br2 battery with a capacity of 500 mAh can be stably cycled for more than 400 times. The battery further scaled up to 1.5 Ah also exhibited excellent electrochemical performance in different series and parallel connections. Furthermore, a Zn-Br2 battery module of 9 Wh (6 V, 1.5 Ah) integrated with a photovoltaic cell panel demonstrated practical energy storage capability.
This research developed an anode-free Zn-Br2 battery with excellent performance by designing the metal/metal-zinc alloy heterostructured interface, which will pave a new way for the application of Zn batteries in large-scale energy storage.
Paper Link: https://doi.org/10.1038/s41467-022-35630-6
(Written by JIANG Zhimo, edited by ZHANG Yihang, USTC News Center)