Chemistry Design for Suppressing Dendritic Growth during Metal Electrodeposition – Applications in Energy Storage Devices

Electrodeposition of metals such as lithium (Li) and zinc (Zn) is central to charging of advanced energy storage devices including lithium-metal batteries and zinc-halogen flow batteries. However, a key technological hurdle facing the development of high energy density rechargeable metal anodes is the formation of dendritic morphology during battery charging and cycling [1,2]. 

In the present talk, key mechanisms underlying the development of dendritic morphology during Li and Zn electrodeposition will be discussed. Mechanistic effects associated with electrolyte components (additives and solvents) will be elucidated through in situ ‘live’ monitoring of the dendrite evolution process [3]. Performance of a variety of additives (polymers, sulfides, carbonates) and solvents (aqueous and organic) in the Li and Zn system will be discussed. In situ dendrite propagation studies will be complemented with electroanalytical studies such as polarization measurements on a rotating disc electrode. As shown in attached Figs. 1 and 2, polarization measurements provide valuable insights into the modulation of surface electrochemical kinetics by additives and solvents. Knowledge of surface polarization then enables quantitative modeling of the dendrite growth propensity and the additives-assisted dendrite suppression efficacy [4,5]. A combination of theory and experiment allows development of a comprehensive framework for characterizing the surface chemistry responsible for the dendritic morphology. Based on this framework, quantitative guidelines for designing chemistries to suppress dendrite formation will be presented.

References:

1. M. Skyllas-Kazacos et al., J. Electrochem. Soc., 158, R55 (2011).
2. K. Xu, Chem. Rev., 104, 4303 (2004).
3. S. Banik and R. Akolkar, J. Electrochem. Soc., 160 (11) D519 (2013).
4. R. Akolkar, J. Power Sources, 232, 23 (2013).
5. R. Akolkar, J. Power Sources, 246, 84 (2014).