Powder-Based Additive Manufacturing of Li-Ion Batteries and Micropowder Mixing Characteristics

Lithium ion battery electrodes were manufactured using a new additive manufacturing process based on dry powders. By using dry powder based process, solvent and drying process used in conventional battery process can be removed which allows large-scale Li-ion battery production be more economically viable in markets such as automotive energy storage systems. Thermal activation time has been greatly reduced due to the time and resource demanding solvent evaporation process needed with slurry-cast electrode manufacturing being replaced by a hot rolling process. It has been found that thermal activation time to induce mechanical bonding of the thermoplastic polymer to the remaining active electrode particles is only a few seconds. By measuring the surface energies of various powders and numerical simulation of powder mixing, the powder mixing and binder distribution, which plays a vital role in determining the quality of additive manufactured battery electrodes, have been predicted and compared favorably with experiments.