The potential application of anode-less sodium metal batteries (ALSBs) is severely affected by the irreversible depletion of sodium ions. Cathode sodium compensation (SC) additive is an effective way for sodium supplement due to its simplicity and flexibility. However, developing SC additives with no toxicity, low cost, low sensitivity to air and humidity is still a huge challenge. In this work, we propose a low-cost, environmentally friendly and air-stable organic sodium salt as sodium reservoir to compensate sodium ion, thus improving the cycle stability of ALSBs. The capacity of ALSBs with N: P as low as 0.5:1 could maintain capacity retention of 91.3% after 100 cycles with this SC additive, while the cell without this SC additive would decline to almost zero after 10 cycles. The inexpensive price and ease of preparation also make it suitable for industrialization. This work provides a realistic SC approach for improving the cycling stability for ALSBs.
Song Yexin,Chen Manjing,Zhong Ziyang,Liu Zhexuan,Liang Shuquan,Fang Guozhao
Developing practical technical index of aqueous zinc metal batteries (ZMBs) is crucial to support safe large-scale energy storage. However, the realistic performance demonstration of ampere hour (Ah)-scale aqueous ZMBs under high mass loading and large areal capacity, which is the key to the industrial application of aqueous ZMBs, remains a critical challenge. In this paper, we propose a bilateral in-situ functionalization strategy in response to the issues that face high mass loading and large areal capacity of aqueous ZMBs. A gradient interface of Zn negative electrode was formed by directional adsorption and in-situ decomposition of organic sodium salt electrolyte additive. It avoids the influences from the fluctuation of electrolyte state and positive electrode dissolution, realizing uniform large-capacity plating/stripping in Ah-scale pouch cell. The positive electrode interface was also in-situ modified by electrolyte additive, which not only facilitated ion intercalation but also suppressed positive electrode dissolution through adsorption at the interface, thereby achieving high-loading stability. As a result, the cyclic stability in coin cell maintained more than 4000 cycles at 2 A g −1 , underscoring the superior compared to its counterpart. More importantly, the Ah-scale pouch cell can last more than 680 cycles with an accumulated capacity of 319.6 Ah. This work offers a roadmap for designing practical Ah-scale ZMB pouch cells.
危险品化学品经营许可证（带存储）