Ultrafast laser structuring of high-voltage cathode materials for lithium-ion batteries

A rather new approach for simultaneously achieving high energy and high-power density of a battery electrode is the use of a high-voltage cathode material in conjunction with a three-dimensional (3D) electrode architecture created through ultrafast laser structuring. In the presented work, LiNi0.5Mn1.5O4 (LNMO) cathodes were laser structured using a high-power ultrashort pulsed laser source with an average laser power up to 300 W. An investigation of the ablation behavior of LNMO cathodes was performed by a variation of laser and process parameters. The impact of the laser pulse peak fluence and the repetition rate on the ablation depth and width of the generated grooves was analyzed, while keeping the pulse-to-pulse distance constant. An electrochemical analysis of unstructured and selected laser structured LNMO cathodes was conducted to study the influence of the laser structuring on the electrochemical performance. It could be shown that the combination of LNMO with the advantages of a 3D electrode design is leading to outstanding electrochemical properties.