LaNi5對Mg2Ni合金電極性質之影響

Effect of LaNi5 additions on electrode properties of Mg2Ni alloys

胡賢君(Hsien-Chung Hu)

指導教授 ： 李勝隆

國立中央大學/工學院/材料科學與工程研究所/碩士(2011年)

摘要

本研究首先利用自行開發之恆溫揮發鑄造法(Isothermal Evaporation Casting Process，IECP)製備Mg2Ni合金與利用電弧熔煉法(Arc-melting)製備LaNi5合金後，將此兩種儲氫合金進行不同含量及時間的球磨混合，並製備成電極，以觀測其電極性質的變化。
藉由結構鑑定與電化學性能測試以探討混合後合金之放電電容量及充放電循環壽命。結果顯示，Mg2Ni合金電極之電容量隨球磨改質時間的增加而上升；鑄態Mg2Ni與鑄態LaNi5進行6小時球磨，可加速Mg2Ni奈米晶化的形成，但對循環壽命的提升上並無明顯助益；以球磨24小時之Mg2Ni與經活化處理過之LaNi5進行短時間及不同LaNi5含量之球磨混合，其中球磨混和時間30秒為最佳之混和時間，而添加LaNi5含量達20 wt.%以上始具有使循環壽命均提升之效果。

關鍵字

LaNi5 ； 儲氫合金 ； Mg2Ni ； 電極

並列摘要

Mg2Ni alloys were prepared by Isothermal Evaporation Casting Process (IECP) and LaNi5 were prepared by Arc-melting. These two alloys were mixed by Ball-milling with different amount of LaNi5 and milling time.
Discharge capacity and discharging cycle life were discussed by structure analyzing and Battery Testing System. As a result, the discharge capacity of Mg2Ni was increased with the ball milling time increased. Mg2Ni ball milled with LaNi5 with a long time (such as 6 hr) could increase the rate of tending to amorphousness, but could not increase the cycle life of alloy. We mixed the 24-hour ball-milled LaNi5 with Mg2Ni at different mixing time and mount of LaNi5 by ball-milling. The best mixing time of ball-milling was 30 second. Moreover, the cycle life of Mg2Ni was increased if the additive amout of LaNi5 was over 20 wt.%.

並列關鍵字

Mg2Ni ； hydrogen storage alloy ； electrode ； LaNi5

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