Determination of thermodynamic, kinetic and interfacial properties for the Li//LixMn2O4 system by electrochemical techniques

✍ Scribed by J. Barker; R. Pynenburg; R. Koksbang

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 767 KB
• Volume: 52
• Category: Article
• ISSN: 0378-7753
• DOI: 10.1016/0378-7753(94)01958-4

✦ Synopsis

Thermodynamic,

kinetic and impedance studies of the Li//Li,Mn,O, (spine1 phase) have been carried out using a polymerbased electrolyte system. There appear to be three voltage ranges for the reversible lithium intercalation reaction, centered around 4, 2.9 and 1.1 V versus L&i+. A ceil utilizing all three ranges shows good coulombic reversibility but also relatively high cell impedance at the lower cell voltage. The upper voltage range shows excellent reaction kinetics, good c&lombic reversibility and low cell impedance.

A third and previously unidentified structural or electronic modification in the spine1 phase has been found at about 3.9 V versus L&i'.

The 2.9 V plateau is characterized by reasonable coulombic reversibility, slower reaction kinetics and higher cell impedance than the upper voltage region. The voltage region around 1.1 V versus Li/Li' is considered too low for practical application.