A study of zinc corrosion and electrodeposition- properties of Zn-Ni battery and Zn-Air battery

• Main Authors: Shih-Hua Hsu, 許世華
• Other Authors: Jiann-Ruey Chen
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/80962084659440947996

碩士 === 國立清華大學 === 材料科學工程學系 === 89 === Because zinc has high energy capacity and very cheap, we focus on its application for secondary battery in recent years. But there are some disadvantages for zinc electrode on actual application such as: zinc corrosion in concentrated alkaline solutions and zinc oxide produced after discharging dissolved in electrolyte, it will lower energy capacity. The purpose of this study is to discuss zinc corrosion while using electrolyte which was made by 5M,6M and 7M concentrated potassium hydroxide solution and some additives :EDTA, poly ethylene glycol(PEG)200, poly ethylene glycol(PEG)300 and poly ethylene glycol(PEG)600 etc. The negative electrodes using in testing cycle life of battery were made by electrodeposition and the electrolytes were the same as using in zinc corrosion. We expect our electrolyte has two function of preventing zinc corrosion and maintaining discharge capacity. Our result shows that higher average molecule weight of poly ethylene glycol has better preventing zinc corrosion. After a series of cycle life testing, it shows that 0.8%wt EDTA and 0 .2%wt poly ethylene glycol (600) added in 6M concentrated potassium hydroxide solution saturated by zinc oxide has good performance for maintaining high discharge capacity. We put zinc electrode which is made by electrodeposition in 6M concentrated potassium hydroxide solution saturated by zinc oxide and added by 0.8%wt EDTA and 0 .2%wt poly ethylene glycol (600) in some different conditions, charged by several current 100mA, 200mA and 300mA and discharged by the same current, 0.15A, in order to find out the suitable condition for cycling. It shows that higher charging current has better performance for keeping discharge capacity. Finally, we use zinc electrode which is made by electrodeposition in zinc-air battery application, it has discharge capacity, 573mAh/g. For testing polarization on zinc-air battery, we change some different constant discharge current, 1mA, 5mA, 10mA and 20mA to measuring the effects of battery voltage.