15 Apr

New Application Note from Asylum Research: Operando EC-AFM Imaging of Li-O2 Battery Solid-Electrolyte Interphase

Worldwide demand for energy storage is growing as mobile devices continue to proliferate and environmental concerns encourage the adoption of electric vehicles. Performance expectations for these batteries continue to increase as well. Capacity, lifetime, and safety are just a few of areas where researchers actively work to develop improved battery technologies. Batteries are electrochemical devices, and so much work focuses on understanding the material science and chemistry of the electrode materials and electrolytes. However, batteries also undergo structural changes during their charge and discharge cycles. These structural changes are found to greatly influence the lifetime of batteries and sometimes their safety. Atomic Force Microscopy (AFM) may be the only tool that can characterize these structural changes inside an operational battery.

Image caption: The Cypher ES AFM can directly visualize the nucleation of interphase material that forms on the battery cathode during discharge (left) and its dissolution during charge cycles (right).

The new application note presents how Electrochemical AFM imaging can directly visualize the solid-electrolyte interphase that forms during lithium-oxygen (Li-O₂) battery operation. A key challenge in these studies is that lithium is highly reactive with water and oxygen, so the studies must be conducted in the controlled environment of a glovebox. However, the electrochemical reaction also requires a controlled concentration of oxygen in the battery cell. The Asylum Research Cypher ES AFM is uniquely capable of this research because its electrochemistry cell accessory enables the local environment to be controlled at the cell, isolated from the inert environment inside the glovebox. The Cypher ES is also exceptionally immune to the vibration and noise generated by glovebox operation, which enables higher resolution imaging. Investigations like these will be critical to the development of next-generation batteries.

For more information see https://afm.oxinst.com/Li-Battery