Method for Fabrication of copper foam by electrodeposition

본 발명은 전해도금법에 의한 다공성 구리의 제조방법에 관한 것이다. 보다 상세하게는 전해도금으로 발생하는 수소를 틀(template)로 사용하여 다공성 구리(copper foam)를 제조함에 있어 전착시 첨가제로서 무기계는 암모늄(NH4+)과 염소(Cl-)가 사용되고, 유기계는 폴리에틸렌글리콜(PEG)과 MPSA(3-mercapto-1-propane sulfonic acid)를 첨가하여 밀도와 강도가 우수한 다공성 구리를 제조하는 방법에 관한 것이다. 본 발명의 다공성 구리는 3차원적으로 상호 연결된 기공으로 구성되어 표면적이 극대화된 다공성 구리를 제공한다. 전해도금법(electrodeposition), 다공성 구리, 무기계 첨가제, 유기계 첨가

리튬이차전지용 주석계 음극의 표면형상 및 미세구조 변화가 전기화학적 특성에 미치는 영향

학위논문(박사) - 한국과학기술원 : 신소재공학과, 2010.08, [ xiii, 143 p. ]Sn has received much attention as an alternative anode material for lithium ion batteries due primarily to its high theoretical capacity (994 mAh g-1). Sn anodes, however, have exhibited poor cyclability due to the crumbling by severe volume expansion (up to about 260%) that occurs during alloying of $Li^{+}$ with Sn. In this study, Sn based anodes have been designed to improve their charge/discharge performances by adopting the two strategies; i) Synthesis of porous Sn anode with a multi-layered structure by electrodeposition, The electrochemical performance of a Sn electrode synthesized on Cu foil by electrodeposition in a pyrophosphate-based bath was examined by modifying its morphology by controlling the cathodic current density. As the cathode current density increased, the morphology of the electrodeposit changed from a smooth-compact structure to a microscopically multi-layered structure with open spaces between adjacent layers. The porosity of the multi-layered Sn electrode was measured to be more than 60% of its volume. The cycle performance and coulombic efficiency of the multi-layered Sn electrode were higher than those of the smooth Sn electrode, due primarily to the buffering effects of the open spaces between the layers against the volume expansion of the Sn anode during cycling. ii) Synthesis of Sn anode by electrodepositing Sn on a porous Cu foam substrate, The effects of Cu substrate morphology and post electrodeposition on the porosity, adhesion as well as the mechanical strength of Cu foam electrodeposits are examined. The porosity of Cu foam is enhanced by changing the morphology of the Cu substrate from smooth to nodular because $H_2$ bubbles are split into small bubbles by the nodules. In addition, the adhesive properties of Cu foam deposited on the nodular Cu foil are improved by the mechanical interlocking effects of the nodules. As a result of post electrodeposition treatment, the mechanical strength of the Cu foam is significa...한국과학기술원 : 신소재공학과