Search for: All records

Silicon is an emerging anode material due to its high lithium storage capacity. While some commercial batteries now include silicon particles, porous three-dimensional (3D) scaffolded silicon electrodes may enable higher silicon loading by accommodating the silicon volume expansion during lithiation without significant electrode swelling. However, the electrochemomechanical response of silicon films on metal scaffolds remains poorly understood due to the complex scaffold morphology. We explore the role of scaffold curvature in the cycling behavior of silicon films and show that different curvatures exhibit distinctive failure modes. Negative curvature leads to crack opening from tensile and compressive stresses. Positive curvature induces tensile stress-driven buckling. Zero curvature exhibits fragmentation. The electrode morphology and chemistry for these systems are evaluated via scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy (STEM-EDS). COMSOL Multiphysics simulations support that the electrochemo-mechanics of silicon are curvature-dependent. These findings point toward design strategies for 3D architected silicon anodes with improved cycling integrity. 

Abstract Sustainable battery production is a major challenge for the future of electrification with the rise in battery production leading to a massive increase in demand for battery cathode materials. Needed are environmentally responsible ways to recycle used cathodes into new cathodes to create a circular economy for batteries. While some battery recycling and recovery techniques for battery components are developed, they can involve costly and environmentally impactful multi‐step processes. This work demonstrates for the first time the simultaneous dissolution and electrochemical deposition of Li‐ion transition metal oxide cathodes, providing a path to directly fabricate new battery cathodes from old battery cathodes. The LiCoO₂cathodes formed via this recycling process exhibit near‐theoretical capacities, are binder and additive‐free, and are phase pure. Technoeconomic and life cycle analyses show the simultaneous dissolution and electrochemical deposition process is less costly and environmentally harmful than traditional pyrometallurgical, hydrometallurgical, and direct recycling methods. This method has major potential impacts and advantages on the industrial scale as it creates battery materials in fewer steps at a lower cost and with a lower environmental impact than current battery recycling methods.