Summary
Electrochemical screening of active materials, in its simplest form, is typically achieved by measuring the first cycle lithiation and delithation capacity in half-cells and calculating a corresponding first cycle coulombic efficiency (FCE). The information obtained in this type of testing can be useful for cell design, computing initial energy density and requires approximately 20 h. It does not, however, offer information that can help in making lifetime predictions for when the active material is used in full cells. Metrics like CE measured in half cells are usually obscured by the near-infinite lithium inventory of lithium foil that is accessible each lithiation. Typically, lifetime predictions are made and confirmed based on data collected in full cells. This is accompanied by the time and expense of a full cell build, along with lengthy full cell testing times.
The method presented here is designed to allow a quantitative ranking among different materials to be made from tests on coin half cells, that can be translated to form a qualitative lifetime prediction in full cells. This facilitates high throughput, laboratory scale testing that can respond quickly to material developments without requiring the assembly of full cells, which often requires access to pilot scale facilities.
