Lithium-ion batteries have become a crucial power source for the constantly expanding world of gadgets. They have also, on some occasions, been known to burst into flames.
To provide an understanding into what goes wrong when batteries fail and how to solve the safety risk issue, Researchers report in the journal ACS Sensors that they have devised a potential technique to monitor lithium ions as they move in a battery.
In principle, rechargeable batteries function by moving ions to and fro between electrodes through an electrolyte. Frequently, failure occurs when lithium ions wander from their pre-determined path. To properly understand how this takes place, Researchers have searched for ways to monitor the ions.
Several techniques have been suggested, but thus far, they have been inadequate for a number of reasons, including poor spatial resolution. Fluorescence microscopy, which is commonly used to probe biological systems and materials, could possibly fill this gap. But first, Researchers would need to discover a fluorescent label that is sensitive to lithium ions. Randall H. Goldsmith and colleagues at the University of Wisconsin-Madison got together to achieve this.
The Researchers made use of 2-(2-hydroxyphenyl)naphthoxazole (HPNO), a molecule that fluoresces when it links to lithium ions. They incorporated a "visible pump" to help stop photobleaching and other damage. In a battery-like environment, the system was able to image and monitor lithium ions. The Researchers state that their following step would be to analyze the molecule in a more accurate analog of a battery cell.