Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/9511
標題: 電解沉積摻雜Li於NiO薄膜鋰離子電池負極材料特性之研究
Preparation and Characterization of Electrochemical NiO film doped with Li on Stainless Steel as Negative Electrodes for Thin-Film Lithium Ion Batteries
作者: 黃盈慈
Huang, Y.c
關鍵字: Negative Electrodes;薄膜鋰離子電池;NiO;Thin-Film Lithium Ion Batteries;負極材料;氧化鎳
出版社: 材料工程學研究所
摘要: 
摘 要
本研究的目是在Ni(NO3)2水溶液中利用電化學方法,以定電壓方式陰極沉積及燒結NiO/LiNiO2/Ni2O3薄膜於不銹鋼基材上,並利用XRD、TGA/DTA、SEM/EDS、AFM 、TEM、 Raman Spectroscopy及充放電測試,分析薄膜的特性和電化學性質。
由陰極極化曲線實驗推論Ni(NO3)2水溶液中陰極反應分為三個階段:
1. O2 + 4H+ + 4e- → 2H2O (0.5 V ~ 0. 28V vs. Ag/AgCl )
2. O2 + 2H2O+2e- → 4 OH- (0.28 V ~ -0.43 V vs. Ag/AgCl )
3. 2H2O + 2e- → H2 + 2OH- (-0.43 V ~ -2.5 V vs. Ag/AgCl )
於第三階段電解沉積Ni(OH)2/LiOH薄膜,經過300℃ 1小時燒結後可得NiO及少量的LiNiO2/Ni2O3,晶粒尺寸約6nm,在不同電解質LiPF6和LiClO4下進行CV及充放電測試,以鋰金屬當參考電極及輔助電極,於放電時發生兩個反應:
1. Ni2O3 + 2Li+ + 2e- Li2O + 2NiO (1.5V vs. Li+/Li)
2. NiO + 2 Li+ + 2e- Ni + Li2O (0.38V vs. Li+/Li)
在充電過程除了1及2的逆反應之外,還有 LiNiO2 + NiO Ni2O3 + Li+ + e- (2.2V vs. Li+/Li) 反應式發生,但充電過程中僅1及2可逆,在電解質比較中,LiPF6的可逆性比LiClO4差,因為有LiF形成。NiO薄膜電極於LiClO4電解質中,在50次充放電後電容量還有439mAh/g。

Abstract
The electrolytic deposition of NiO /LiNiO2/Ni2O3 thin film on stainless steel was conducted in Ni(NO3)2 aqueous solution to be used as a negative electrode in lithium ion thin film batteries. The cathode polarization curves include 3 major electrochemical reactions:
1. O2 + 4H+ + 4e- → 2H2O (0.5 V ~ 0. 28V vs. Ag/AgCl )
2. O2 + 2H2O+2e- → 4 OH- (0.28 V ~ -0.43 V vs. Ag/AgCl )
3. 2H2O + 2e- → H2 + 2OH- (-0.43 V ~ -2.5 V vs. Ag/AgCl )
The coated specimen or the coating film carried out at 3rd step was subjected to annealing treatments and further characterized by XRD, TGA/DTA, SEM/EDS, AFM,TEM and Raman Spectroscopy. The as-coating film was Ni(OH)2/LiOH, condensed into NiO partially oxidized into LiNiO2/ Ni2O3 at 300℃ for 1h with the particle size is 6nm. The NiO coated specimen was further characterized by CV analysis and charge-discharge tests in LiPF6 and LiClO4 electrolytes respectively using Li metal as the reference and auxiliary electrode. During discharging tests, two electrochemical reactions occurred : The 1st , Ni2O3 + 2Li+ + 2e-
Li2O + 2NiO, and the 2nd , NiO + 2 Li+ + 2e- Ni + Li2O. Beside the reverse reaction the 1st and 2nd, another reaction LiNiO2 + NiO
Ni2O3 + Li+ + e- occurred for charging tests. The 1st and 2nd reactions are reversible. Also, the reversibility in LiPF6 was worse than that in LiClO4 , since LiF was formed. The capacity of NiO coated specimen was still found 439 mAh/g after 50 charge-discharge cycles test in LiClO4 electrolyte.
URI: http://hdl.handle.net/11455/9511
Appears in Collections:材料科學與工程學系

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