Advanced electrode design enables homogeneous electric field distribution for metal deposition studies via in situ liquid cell TEM

<i>In situ</i> liquid-phase electrochemical transmission electron microscopy (ec-TEM) as a valuable technique has been widely used in studying metal deposition in battery materials. While real-time observations of metallic nucleation, growth, and dendrite formation using microscale ec-TEM liquid cells are investigated, existing cells exhibit nonuniform electric field distribution along electrodes, limiting measurement reliability and quantitative analysis. Here, we introduce an advanced electrode design for ec-TEM chips, ensuring a uniform electric field for precise characterization of early-stage metal deposition closer to practical battery conditions. Both simulation and experimental investigations demonstrate that these specially designed ec-TEM chips facilitate quantitative electrochemical characterization combined with the <i>in situ</i> TEM technique in comparison with commercially available chips. We thus provide a significant progression toward optimizing the performance and reliability of quantitative <i>in situ</i> liquid-phase TEM measurements, essential for understanding and improving electrochemical systems.