This thesis describes research to understand the relationships between materials, microstructure, transport processes, and battery performance for primary alkaline battery cathodes. Specifically, the effect of various carbon additives, with different physical properties, on electronic transport or conductivity within battery cathodes was investigated. Generally, the electronic conductivity increases with carbon additives that have higher aspect ratios, smaller particle diameters, higher surface areas, and lower bulk densities. Other favorable carbon aspects include more aggregated and elongated carbon domains which permit good particleto-particle contacts. Of the various carbon additives investigated, graphene nanopowder was the best performer. This graphene nanopowder had the smallest particle diameter, highest surface area, and one of the lowest Scott densities of the carbon additives investigated as well as well-connected, interspersed carbon pathways. Notably, a typical effective ionic conductivity is more than 50 times less than the electronic conductivity (5.7 S/m to 300 S/m, respectively) for a high-performance cathode. Thus, alkaline battery cathodes could be redesigned to improve ionic conductivity for optimal performance. This work expanded on previously published work by relating additional carbon-additive material properties--specifically, particle morphology, surface area and Scott density--and their corresponding cathode microstructure to the fundamental transport processes in alkaline battery cathodes.
College and Department
Ira A. Fulton College of Engineering and Technology; Chemical Engineering
BYU ScholarsArchive Citation
Nevers, Douglas Robert, "The Effect of Carbon Additives on the Microstructure and Performance of Alkaline Battery Cathodes" (2013). Theses and Dissertations. 3689.
electronic conductivity, porosity, alkaline battery, cathode microstructure