Many MindedPatterned copper and a thin MXene layer aim to extend anode-free battery life
KAIST in South Korea announced on September 22 a technology meant to make anode-free EV batteries last longer. The team was led by Professors Jinwoo Lee and Hee-Tae Jung of the Department of Chemical and Biomolecular Engineering, with Kyungpook National University and the National NanoFab Center also taking part.
Anode-free cells drop graphite and let lithium plate directly onto copper foil, which saves weight and thickness. The trouble is that lithium deposits unevenly and forms dendrites, and the protective layer on the surface is unstable, so the cell degrades quickly. Earlier fixes, such as adding extra lithium or thicker coatings, brought back the bulk the design was meant to remove.
The researchers used secondary sputtering lithography, a semiconductor fabrication technique, to pattern the copper with microscopic tubes about 300 nm across and 150 nm tall. This gives lithium about four times the surface area of flat foil. They then added a MXene coating about 10 nm thick. In a LiPF6-based electrolyte, it encourages a protective layer rich in lithium fluoride, which limits side reactions and dendrite growth. They analyzed that layer with XPS, ToF-SIMS and TEM, limiting air exposure of the samples.
The abundance case is simple. If anode-free cells can be made durable, packs get lighter and smaller for the same energy, which can lower cost and extend range, and that makes electric transport more accessible. The approach also adds only nanometers of material, so it avoids the weight penalty of earlier fixes.
The caveats are large. The excerpt we worked from gives no cycle-life, energy-density or driving-range figures. Results come from laboratory experiments, and nothing shows the process can scale to EV production. The range benefit remains potential. Watch for quantified cycle data and any pilot-scale cells.
Source: ScienceDaily