Catalyzing Battery Materials Research via Lab-Made, Sub-Ampere-Hour-Scale Pouch Cells, and Long-Term Electrochemical Monitoring by a Reparable Reference Electrode

Battery materials research is of crucial importance to the development of next-generation batteries. However, the transition from lab-scale studies, typically in gram quantities, to industrially relevant ones (i.e., kilogram scale) has been holding back by challenges in scale-up synthesis and a lack of reliable approaches to verify the electrochemical performance of the lab-made materials. Here the design and assembly procedures of sub-Ah-scale pouch cells that provide validations of several lab-made Li-ion and Na-ion cathode materials available in a limited quantity (<5 g) are reported. These lab-made pouch cells show superior cycle stability and consistency over the widely used coin cells, exemplified by multiple Ni-rich layered oxide-graphite full batteries retaining 84.29 +/- 0.16% of the initial capacities over 1000 cycles. A four-electrode pouch cell with a reparable reference electrode is further designed to monitor impedance growth and Li plating during long-term electrochemical tests. It can be further integrated with in situ ultrasonic imaging to enable multi-modal studies. This work provides a powerful platform to evaluate and boost the technology readiness levels of laboratory-discovered battery materials.