Sol–gel fabrication of lithium-ion microarray battery

Microarray electrodes of LiMn2O4 and Li4/3Ti5/3O4 were prepared on a glass substrate using a sol–gel method. The prepared LiMn2O4 and Li4/3Ti5/3O4 microarray electrodes were characterized with scanning electron microscopy, Raman spectroscopy, and cyclic voltammetry. Using a polymer-gel electrolyte, lithium ion microbattery of Li4/3Ti5/3O4/polymer-gel/LiMn2O4 (cell area: 6.6 × 10−2 cm2) was successfully constructed. The microbattery operated reversibly at 2.5 V, and the discharge capacity was 300 nA h, which corresponded to an energy density of 11 μW h cm−2.