Strengthening the Electrodes for Li-Ion Batteries with a Porous Adhesive Interlayer through Dry-Spraying Manufacturing

ACS Appl Mater Interfaces. 2019 Jul 17;11(28):25081-25089. doi: 10.1021/acsami.9b03020. Epub 2019 Jul 5.

Abstract

The manufacturing technologies for electrodes have a great influence on the performance of Li-ion batteries. Manufacturing procedures largely determine the microstructure of electrodes, and thus affect how active materials are involved in the electrochemical reactions. However, the usage of solvent in the dominant slurry-casting method weakens its competence on obtaining desired microstructures and properties. In this study, an improved adhesion strength is achieved during the fabricaion of graphite anodes with our solvent-free manufacturing method. Through dry-spraying an interfacial "adhesion enhancer" layer between the current collector and the electrode coating, the mechanical strength (from 0.5 kPa to over 83.0 kPa) and electrochemical performance (from 24.2% to 92.4% as the capacity retention in 100 cycles) are significantly improved. Results here demonstrate a simple and economical route to practically control the microstructure of electrodes during manufacturing and potentiate the strategy enabled by dry-spraying to design and manufacture advanced batteries.

Keywords: additive manufacturing; graphite anode; lithium-ion battery; mechanical property; solvent-free.