材料研究学报
材料研究學報
재료연구학보
CHINESE JOURNAL OF MATERIALS RESEARCH
2006年
1期
83-88
,共6页
李义兵%陈白珍%李改变%金基明
李義兵%陳白珍%李改變%金基明
리의병%진백진%리개변%금기명
无机非金属材料%斜方锰酸锂%固相法%电化学行为
無機非金屬材料%斜方錳痠鋰%固相法%電化學行為
무궤비금속재료%사방맹산리%고상법%전화학행위
inorganic non-metallic materials%orthorhombic LiMnO2%solid-state reaction%electro-chemical behavior
用一步固相法合成了斜方锰酸锂,对其进行了表征并确定了前驱体化合物烧结中的转变过程,以及相互化合间的烧结机制.结果表明,随着煅烧温度的升高,杂相减少,生长出主体相斜方锰酸锂.在700℃以上可以生成均一相的层状斜方类球状和棒状锰酸锂颗粒.两种颗粒的粒度分别为1~5 μm和5~15 μm.在充放电循环中,斜方锰酸锂结构易于向尖晶石结构转变.在2.5~4.5 V范围内以20 mA/g电流进行充放电循环,斜方锰酸锂的初始充电容量达到247 mAh/g,放电容量为133 mAh/g,50次循环后,容量保持率为92%.
用一步固相法閤成瞭斜方錳痠鋰,對其進行瞭錶徵併確定瞭前驅體化閤物燒結中的轉變過程,以及相互化閤間的燒結機製.結果錶明,隨著煅燒溫度的升高,雜相減少,生長齣主體相斜方錳痠鋰.在700℃以上可以生成均一相的層狀斜方類毬狀和棒狀錳痠鋰顆粒.兩種顆粒的粒度分彆為1~5 μm和5~15 μm.在充放電循環中,斜方錳痠鋰結構易于嚮尖晶石結構轉變.在2.5~4.5 V範圍內以20 mA/g電流進行充放電循環,斜方錳痠鋰的初始充電容量達到247 mAh/g,放電容量為133 mAh/g,50次循環後,容量保持率為92%.
용일보고상법합성료사방맹산리,대기진행료표정병학정료전구체화합물소결중적전변과정,이급상호화합간적소결궤제.결과표명,수착단소온도적승고,잡상감소,생장출주체상사방맹산리.재700℃이상가이생성균일상적층상사방류구상화봉상맹산리과립.량충과립적립도분별위1~5 μm화5~15 μm.재충방전순배중,사방맹산리결구역우향첨정석결구전변.재2.5~4.5 V범위내이20 mA/g전류진행충방전순배,사방맹산리적초시충전용량체도247 mAh/g,방전용량위133 mAh/g,50차순배후,용량보지솔위92%.
Orthorhombic LiMnO2 material was synthesized via a one-step solid-state reaction and characterized, and the conversion process of mixture at calcination condition and the mechanism of intercalation reaction were confirmed. It was found that impurities decrease and host phase o-LiMnO2 increases with elevating temperature. Homogeneous o-LiMnO2 sized from 5~15μm with a bar shape and 1~5μm with small spherical shape can be refined above 700℃. The layered orthorhombic LiMnO2 is easy to transform to spinel structure during cycles. The first charge-discharge capacity is 247 mAh·g-1and 133 mAh·g-1 between 2.5 V and 4.5 V at current rate 20 mA·g-1,respectively,and capacity retentionrate can keep at 92 after 50 cycles.