Magnesium Alginate as an Electrolyte for Magnesium Batteries

Journal Article (2025)
Author(s)

M.C. Kwakernaak (TU Delft - RST/Storage of Electrochemical Energy)

L.K. Kiriinya (TU Delft - RST/Storage of Electrochemical Energy, University of Nairobi)

W. J. Legerstee (Rotterdam University of Applied Sciences, TU Delft - RST/Storage of Electrochemical Energy)

W.M.J. Berghmans

C.G.T. Hofman (Student TU Delft)

E.M. Kelder (TU Delft - RST/Storage of Electrochemical Energy)

Research Group
RST/Storage of Electrochemical Energy
DOI related publication
https://doi.org/10.3390/batteries11010016
More Info
expand_more
Publication Year
2025
Language
English
Research Group
RST/Storage of Electrochemical Energy
Issue number
1
Volume number
11
Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Abstract

We present magnesium alginate as an aqueous polymer electrolyte for use in magnesium batteries. Alginates are polysaccharides extracted from algae, which form hydrogel materials upon interaction with divalent and trivalent cations. They are renewable, non-toxic, biocompatible materials that are widely used in the food and pharmaceutical industries. Mg2+ is weakly bound to an alginate polymer, which results in a hydrogel-like material that contains mobile magnesium ions. We propose that this is the ideal situation for an electrolyte that behaves in a similar way as a ‘water-in-salt’ system. Magnesium alginate was successfully synthesized and characterized by FTIR, XRD, and PDF. Ionic conductivity was measured with EIS measurements; a 2 wt% magnesium electrolyte shows a conductivity of 1.8 mS/cm. During conductivity experiments, we noticed the formation of a black layer on magnesium electrodes, which can improve the ionic conductivity between the electrodes. We carefully characterized this layer with XPS and saw that it mainly consists of alginate derivatives.