ISSN : 1225-0112(Print)
ISSN : 2288-4505(Online)
ISSN : 2288-4505(Online)
Research Papers : The Electrochemical Properties of AgxCuyV2O5 Xerogel for Lithium Secondary Batteries
Abstract
In order to improve the properties of vanadium oxide as cathodes, Ag_xCu_yV_2O_5 gel was synthesized by deliberately adding a small amount of Ag and Cu to a V_2O_5 sol derived via sol-gel process. The electrochemical properties of a new mixed oxide Ag_xCu_yV_2O_5 xerogel as a Li intercalation compound have been investigated in the relation with structural characteristics. It appeared the amorphous layered material and entangled fibrous textures have been grown to form anisotropic corrugated fibrils. The specific capacity and rate characteristics were dependent upon the added amount of dopant, Cu and Ag. Average specific capacity of the Ag_xCu_yV_2O_5 xerogel was more than 120 mAh/g, and coulombic efficiency was at least ninety percent. The overall electrochemical properties, the reversibility and cell capacity, were enhanced compared to the undoped vanadium pentoxide.
연구논문 : 리튬이차전지용 AgxCuyV2O5 Xerogel의 전기화학적 특성
초록
바나듐 산화물계 양극소재의 물성을 향상시키고자 졸겔법을 이용하여 제조한 V_2O_5 xerogel에 미량의 Ag와 Cu 원소를 도핑시켜 Ag_xCu_yV_2O_5 xnogel을 제조하여 리튬이차전지용 양극소재로서의 전기화학적 및 표면특성을 연구하였다. Ag_xCu_yV_2O_5 xnogel은 무정형의 층상 intercalation 소재로 표면구조는 섬유모양의 단위체가 서로 얽혀 일정한 방향으로 성장하여 비등방성 sheet를 형성하고 있다. 도핑되어진 Ag와 Cu의 양에 따른 전지용량 및 출력특성 등이 첨가량에 따라 변하였다. 전지의 평균용량은 적어도 120 mAh/g 이상이며 coulombic efficiency는 90% 이상으로 산화 ·환원과정이 가역적이며 사이클 특성이 우수하였다.