(119a) Design of Particles and Electrodes for Electrochemical Energy Storage

Lithium-ion batteries have become a commercially successful battery technology; however, there is still significant room for improvement. Much progress in battery technology historically has come from advances in materials chemistry; however, other factors can have significant impact on battery performance. In particular, heterogeneity with regards to the particles that store energy in lithium-ion batteries and their organization in the electrode causes challenges with regards to maximizing energy density and keeping the electrochemical activity throughout the cell uniform.

Our group has focused its efforts on synthesizing battery active material particles with controllable morphologies. We have developed methods to tune the size, shape, and composition of precursor particles that are subsequently converted to battery active material particles. Our ultimate goal is to develop approaches to produce controlled particle morphologies using a variety of battery materials, and thus to design particles suited to a specific electrode processing or cell geometry. In this talk, the recent efforts within our group to control battery morphology and composition will be described, as well as some of our planned battery concepts.

This talk will describe advances in two areas in our lab with regards to particle and electrode design and control. In the first part, we will describe efforts to take advantage of explicit control over solution chemistry to control the composition and morphology of lithium-ion battery precursor particles. Control over precipitation of transition metals in battery precursors has been largely unreported in the open literature, and we will describe conditions where explicit control over the precipitation of transition metals is necessary to avoid the formation of phases detrimental to final battery material performance. In addition, the impact of shape modifying agents on particle composition and morphology will also be described. The second part of the talk will discuss efforts in our lab to control and characterize lithium-ion battery electrodes. For some lithium-ion battery systems, the electrode architecture and ion transport through the electrode can be the major limitation to achieving higher discharge currents. We will describe our efforts to characterize the electrode architecture, and possible routes to design particles that will help to maximize the energy density of battery electrodes.