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Materials characterization is fundamental to our understanding of lithium ion battery electrodes and their performance limitations. Advances in laboratory-based characterization techniques have yielded powerful insights into the structure–function relationship of electrodes, yet there is still far to go. Further improvements rely, in part, on gaining a deeper understanding of complex physical heterogeneities in the materials. However, practical limitations in characterization techniques inhibit our ability to combine data directly. For example, some characterization techniques are destructive, thus preventing additional analyses on the same region. Fortunately, artificial intelligence (AI) has shown great potential for achieving representative, 3D, multi-modal datasets by leveraging data collected from a range of techniques. In this Perspective, we give an overview of recent advances in lab-based characterization techniques for Li-ion electrodes. We then discuss how AI methods can combine and enhance these techniques, leading to substantial acceleration in our understanding of electrodes.

Electron transport layers (ETLs) have been instrumental in breaking the efficiency boundaries of solution-processed photovoltaics. In particular, bilayer ETLs with an MgO top component have afforded tremendous success in various solution-processed systems, such as perovskite photovoltaics, however, their application in the promising technology of organic photovoltaics is limited. In this work, we fabricate organic photovoltaic devices incorporating a “bilayer” ZnO/MgO ETL instead of a single ZnO ETL, so as to reduce the leakage current and boost the power conversion efficiency. The ZnO/MgO ETL is shown to have a more uniform top surface and a lower work function compared to the single ZnO ETL which is expected to be beneficial to electron extraction. Furthermore, we demonstrate that insertion of the thin (≲ 10 nm) MgO interlayer in devices leads to a reduced leakage current and an increase in the shunt resistance. Application of the MgO interlayer boosts the short circuit current density and fill factor, and enhances the power conversion efficiency by ∼10% (relative increase) thereby demonstrating a facile approach to push the efficiency of organic photovoltaics to higher levels.