This special issue is the second part of the proceedings of the 6th Regional Symposium on Electrochemistry – South East Europe (RSE–SEE 6), held in Balatonkenese, Hungary, from 11-15 June 2017 (part 1 has been published in J. Electrochem. Sci. Eng. 8(1) 2018). These are some of the best papers presented at the RSE-SEE6 meeting and reflect the broad interests of the electrochemical community, including both new techniques and application areas. Since its start in 2008, the series of RSE-SEE symposia provides a stimulating international forum for electrochemistry researchers to share their current research results. Following this tradition, more than 110 participants from 24 countries presented papers in Balatonkenese and discussed recent progress in electrochemistry and electrochemical engineering.