Battery testing system (IMAGE) City University of Hong Kong Caption By using this battery testing system, the amount of intercalated lithium ions in layered materials can be controlled effectively by tuning the cutoff voltage. Credit Yang, R., Mei, L., Zhang, Q. et al. /DOI number: 10.1038/s41596-021-00643-w Usage Restrictions Image must be used with appropriate caption and credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.