Design and Operation of an Operando Synchrotron Diffraction Cell Enabling Fast Cycling of Battery Materials

Abstract Operation of a battery typically involves dynamic and non‐equilibrium processes, making real time operando techniques crucial for understanding their nature. Operando X‐ray diffraction is an important technique for investigating metastable intermediates and non‐equilibrium phase transitions in crystalline electrode materials. Currently employed experimental setups often apply a disruptive approach to cell design, whereby the integrity of standard electrochemical cells is compromised to facilitate collection of high‐quality diffraction data. Here, we present a non‐disruptive approach to adapting the use of a standard pouch cell that enables fast and long‐term cell cycling. Suitability of the setup is demonstrated on the well‐studied cathode material LiNi_0.5Mn_1.5O₄. While exhibiting comparable electrochemical behavior to a standard pouch cell up to a current rate of 8 C (∼6.6 mA cm⁻²), phase transitions could be monitored accurately. Thus, the cell provides a new alternative to investigating non‐equilibrium transitions and long‐term aging effects in battery materials.