Zinc-Copper Galvanic Half-Cells: LED Powering and Real-World Potential

From Redox Fundamentals to Real-World Energy Solutions: Optimising Galvanic Cells for Sustainable Power

Abstract

This experiment investigated the production and performance of zinc-copper galvanic cells using accessible materials, with a focus on optimizing voltage output and understanding factors influencing cell efficiency. By varying the factors such as electrolyte concentration, electrode materials, and cell configuration (single cells vs. series connection), we analysed their impact on voltage, current, and ability to power LEDs of varying voltage thresholds. Three electrolyte concentrations (0.1M, 0.5M, 1M, 2M) were tested in different combinations for both zinc sulfate and copper(II) sulfate solutions. Results showed minimal variation in voltage with changing concentration alone, with values ranging from approximately 0.9996 V to 1.0293 V. However, connecting multiple cells in series significantly increased voltage, with three cells in series reaching a voltage of  3.0656 V, which was sufficient to power all tested LED colors. These findings combined with theoretical predictions of Zn-Cu cells, demonstrated fundamental electrochemical principles such as redox reactions and ion migration via salt bridges. The experiment highlights the scalability and practical relevance of galvanic cells for real-world energy applications, reinforcing their role in the ongoing pursuit of efficient, low-cost, and sustainable battery technologies.