Hydronium battery could help unlock grid storage

Hydronium, or H3O+, is a positively charged ion produced when a proton is added to a water molecule. The researchers discovered that hydronium ions could be reversibly stored in a crystalline electrode material consisting of perylenetetracarboxylic dianhydridem, or PTCDA.

According to their work, published in the German Chemical Society’s Angewandte Chemie International Edition, the battery uses dilute sulphuric acid as the electrolyte. The OSU team claims the battery is particularly suitable for high-power energy storage, such as that required to accommodate large quantities of wind and solar on the grid.

“This may provide a paradigm-shifting opportunity for more sustainable batteries," said Xiulei Ji, assistant professor of chemistry at OSU and the corresponding author on the research.

"It doesn't use lithium or sodium or potassium to carry the charge, and just uses acid as the electrolyte. There's a huge natural abundance of acid so it's highly renewable and sustainable."

In the lab, the team observed a large dilation of the PTCDA lattice structure during intercalation, the process where it receives ions between its layers. This indicated that the electrode was being charged and that the PTCDA structure expanded from the addition of hydronium ions, rather than extremely tiny protons.