Characterization of Al-doped spinel LiMn{sub}2O{sub}4 thin film cathode electrodes prepared by Liquid Source Misted Chemical Deposition (LSMCD) technique

摘要

A novel process called Liquid Source Misted Chemical Deposition (LSMCD) was used to synthesize Al-doped LiMn{sub}2O{sub}4 cathode films for Lithium microbatteries. The cathode films were characterized by XRD, SEM, cyclic volatmmetry, and charge/discharge test. LiMn{sub}1.8Al{sub}0.2O{sub}4 film crystallized at 800℃ in rapid thermal annealing (RTA) for 5min under oxygen atmosphere exhibited more improved electrochemical rechargeability than spinel LiMn{sub}2O{sub}4 film because the substitution of Al{sup}(3+) for Mn{sup}(3+) increased Mn-O bonding strength in the spinel framework and suppressed the two-phase behavior of the unsubstituted spinel during the intercalation/deintercalation that is the origin of the failure mechanism in the 4 V region. As a result, LiMn{sub}1.8Al{sub}0.2O{sub}4 film showed an initial discharge capacity of 52 μAh/cm{sup}2 μm and no capacity fade over 100 cycles.