Re-imagining the daniell cell: ampere-hour-level rechargeable Zn-Cu batteries

The Daniell cell (Cu vs. Zn), was invented almost two centuries ago, but has been set aside due to its non-rechargeable nature and limited energy density. However, these cells are exceptionally sustainable because they do not require rare earth elements, are aqueous and easy to recycle. This work addresses key challenges in making Daniell cells relevant to our current energy crisis. First, we propose new approaches to stabilise Zn and Cu plating and stripping processes and create a rechargeable cell. Second, we replace salt bridges with an anion exchange membrane, or a bipolar membrane for alkaline-acid hybrid Zn-Cu batteries operating at 1.56 V. Finally, we apply these changes in pouch cells in order to increase energy and power density. These combined developments result in a rechargeable Daniell cell, which can achieve high areal capacities of 5 mA h cm-2 and can easily be implemented in 1 A h pouch cells. The classic Daniell cell was redesigned to make it rechargeable using gel electrolytes, surface coatings, and ion exchange membranes. The proposed cell chemistry is sustainable, straight-forward to recycle, and can be scaled up to 1 A h cells.

Automated summary

This article introduces improvements made to the Daniell cell to make it rechargeable, including the use of ion exchange membranes as alternatives to salt bridges. These improvements result in increased energy density of the Daniell cell and allow for easy recycling and scalability to higher capacity cells.