(1. 浙江大學(xué) 化學(xué)系, 杭州 310027;
2. 中國(guó)科學(xué)院 金屬研究所 金屬腐蝕與防護(hù)國(guó)家重點(diǎn)實(shí)驗(yàn)室, 沈陽(yáng) 110015)
摘 要: 通過直接化學(xué)反應(yīng)法、化學(xué)共沉淀法以及物理混合方法在可充鋅電極活性物質(zhì)—氧化鋅中摻入鈣添加劑,研究了鋅電極的充放電特性、放電容量及循環(huán)壽命等電化學(xué)性能。SEM分析表明直接化學(xué)反應(yīng)法制備的樣品是基面為四角形的薄片,化學(xué)共沉積法制備的樣品是基面為六角形的多面體。XRD分析表明兩種化學(xué)反應(yīng)方法制備的樣品均為鋅酸鈣晶體,由于制備過程中晶體優(yōu)先生長(zhǎng)方向不同而具有不同的形狀。電極充放電實(shí)驗(yàn)結(jié)果表明,摻鈣鋅電極的電化學(xué)性能明顯優(yōu)于無鈣鋅電極,化學(xué)摻鈣對(duì)鋅電極電化學(xué)性能的改善優(yōu)于物理混合摻鈣。X射線照片表明由鋅酸鈣組成鋅電極的表面活性物質(zhì)分布較均勻,不摻鈣的鋅電極經(jīng)多次充放電循環(huán)后電極表面已基本上沒有活性物質(zhì)。
關(guān)鍵字: 鋅負(fù)極; 氧化鋅; 氫氧化鈣; 鋅酸鈣;循環(huán)壽命
performance of pasted zinc electrode
ZHANG Jian-qing1,2, CAO Chu-nan1,2
(1. Department of Chemistry, Zhejiang University,
Hangzhou 310027, P.R.China;
2. State Key Laboratory for Corrosion and Protection,
Chinese Academy of Science,Shenyang 110015, P.R.China)
Abstract:Calcium additive was added into the active material (zinc oxide) of the pasted zinc electrodes using directly chemical reaction, chemical co-precipitation and physical mixture of zinc oxide and calcium hydroxide. SEM images show that the sample prepared by directly chemical reaction is tetragonal shape and the sample prepared by chemical co-precipitation is hexagonal shape. XRD analyses show that these two samples are calcium zincate crystals. Shapes of calcium zincate crystals result from different prior growth direction of crystal in the preparation process of calcium zincate. The charge/discharge performance, discharge capacity, cycle life and surface pattern of the pasted zinc electrodes were studied. Constant current charge/discharge and X-ray radiographs indicatethat the charge/discharge performance and surface uniformity of the pasted zinc electrodes with calcium zincate are better than those with physical mixture of zinc oxide and calcium hydroxide. The performance of the pasted zinc electrode with calcium additive is always prior to that of the calcium-free pasted zinc electrodes.
Key words: pasted zinc electrode; zinc oxide; calcium hydroxide; calcium zincate;cycle life


