Solution-Based Approach for the Continuous Fabrication of Thin Lithium-Ion Battery Electrodes by Wet Mechanochemical Synthesis and Electrophoretic Deposition

To use lithium-ion batteries (LIBs) as the energy storage system in wearable smart electronic devices, LIBs must be downsized, particularly with respect to their thickness. To address this need, herein a solution-based fabrication process for thin LIB electrodes is proposed. This process involves the powder synthesis of precursor materials through a wet mechanochemical reaction, electrophoretic deposition (EPD) to coat the current collector, and thermal conversion to attain the final electrode active material. Specifically, the wet mechanochemical synthesis of Li1.81H0.19Ti2O5 center dot xH(2)O (LHTO) using a planetary ball mill produces a mixture of nanosheet and nanotube particles. These particles are then uniformly coated onto Cu foil through EPD while controlling the film thickness from 5 to 17 mu m by varying the applied voltage and coating time. Finally, the LHTO/Cu foils are thermally converted into thin Li4Ti5O12/Cu anodes without added conductive materials. The resulting anodes exhibit a discharge capacity of approximate to 50 mu Ah cm(-2) and good cycling performance. Wet milling particle synthesis and EPD coating can both be employed in continuous manufacturing processes, thus constituting an efficient route for fabricating electrodes for thin LIBs.