Author(s):
Prior, Tomás ; Figueira, Joana ; Freitas, Ângela ; Carvalho, David ; Gomes, Beatriz Moura ; Baptista, Manuela C. ; Lebre, Hugo ; Martins, Rodrigo ; Pereira, Luís ; Pinto, Joana Vaz ; Braga, M. Helena
Date: 2025
Persistent ID: http://hdl.handle.net/10362/190111
Origin: Repositório Institucional da UNL
Project/scholarship:
info:eu-repo/grantAgreement/FCT/Concurso de avaliação no âmbito do Programa Plurianual de Financiamento de Unidades de I&D (2017%2F2018) - Financiamento Programático/UIDP%2F50022%2F2020/PT;
Subject(s): All-solid-state batteries; Atomic force microscopy; Colloidal lithography; Copper thin films; Electrochemical impedance spectroscopy; Interface engineering; Microstructured current collectors; Sodium-ion batteries; Analytical Chemistry; Chemistry (miscellaneous); Molecular Medicine; Pharmaceutical Science; Drug Discovery; Physical and Theoretical Chemistry; Organic Chemistry
Description
Funding Information: This research was funded by Agenda “NGS—New Generation Storage”, ref. no. C644936001-00000045, investment project no. 58, under the Incentive System “Agendas for Business Innovation”, funded by the PRR—Recovery and Resilience Plan and the European Union’s NextGenerationEU funds. However, the views and opinions expressed herein are solely those of the author(s) and do not necessarily reflect the views and opinions of the European Union or the European Commission. Neither the European Union nor the European Commission can be held responsible for them. This work also benefited from FCT UIDP/50022/2020 Emerging Technologies–LAETA. Publisher Copyright: © 2025 by the authors.
The integration of microstructured current collectors offers a potential pathway to enhance interface properties in solid-state battery architectures. In this work, we investigate the influence of surface morphology on the electrochemical performance of Zn/Na2.99Ba0.005OCl/Cu electrodeless pouch cells by fabricating copper thin films on microstructured parylene-C substrates using a combination of colloidal lithography and reactive ion etching. O2 plasma etching times ranging from 0 to 15 min were used to tune the surface topography, resulting in a systematic increase in root-mean-square roughness and a surface area enhancement of up to ~30% for the longest etching duration, measured via AFM. Kelvin probe force microscopy-analyzed surface potential showed maximum differences of 270 mV between non-etched and 12-minute-etched Cu collectors. The results revealed that the chemical potential is the property that relates the surface of the Cu current collector/electrode with the cell’s ionic transport performance, including the bulk ionic conductivity, while four-point sheet resistance measurements confirmed that the copper layers’ resistivity maintained values close to those of bulk copper (1.96–4.5 µΩ.cm), which are in agreement with electronic mobilities (−6 and −18 cm2V−1s−1). Conversely, the charge carrier concentrations (−1.6 to −2.6 × 1023 cm−3) are indirectly correlated with the performance of the cell, with the samples with lower CCCbulk (fewer free electrons) performing better and showing higher maximum discharge currents, interfacial capacitance, and first-cycle discharge plateau voltage and capacity. The data were further consolidated with Scanning Electron Microscopy and X-ray Photoelectron Spectroscopy analyses. These results highlight that the correlation between the surface morphology and the cell is not straightforward, with the microstructured current collectors’ surface chemical potential and the charge carriers’ concentration being determinant in the performance of all-solid-state electrodeless sodium battery systems.
