Aluminum-air battery with cotton substrate:Controlling the discharge capacity by electrolyte pre-deposition  

作　　者：Wending Pan Yifei Wang Holly Y.H.Kwok Dennis Y.C.Leung 

机构地区：[1]Department of Mechanical Engineering,The University of Hong Kong,Hong Kong,China

出　　处：《Green Energy & Environment》2023年第3期757-766,共10页绿色能源与环境（英文版）

基　　金：the SZSTI of Shenzhen Municipal Government (JCYJ20170818141758464);the CRCG grant of the University of Hong Kong (201910160008)for providing funding support to the project.

摘　　要：Conventional Al-air battery has many disadvantages for miniwatt applications,such as the complex water management,bulky electrolyte storage and potential leakage hazard.Moreover,the self-corrosion of Al anode continues even when the electrolyte flow is stopped,leading to great Al waste.To tackle these issues,an innovative cotton-based aluminum-air battery is developed in this study.Instead of flowing alkaline solution,cotton substrate pre-deposited with solid alkaline is used,together with a small water reservoir to continuously wet the cotton and dissolve the alkaline in-situ.In this manner,the battery can be mechanically recharged by replacing the cotton substrate and refilling the water reservoir,while the thick aluminum anode can be reused for tens of times until complete consumption.The cotton substrate shows excellent ability for the storage and transportation of alkaline electrolyte,leading to a high peak power density of 73 mW cm^(-2) and a high specific energy of 930 mW h g^(-1).Moreover,the battery discharge capacity is found to be linear to the loading of pre-deposited alkaline,so that it can be precisely controlled according to the mission profile to avoid Al waste.Finally,a two-cell battery pack with common water reservoir is developed,which can provide a voltage of 2.7 V and a power output of 223.8 mW.With further scaling-up and stacking,this cotton-based Al-air battery system with low cost and high energy density is very promising for recharging miniwatt electronics in the outdoor environment.

关 键 词：Al-air battery Cotton-based Electrolyte pre-deposition Capacity control Miniwatt electronics 

分 类 号：TM911.41[电气工程—电力电子与电力传动]