Performance Characterization of a Low-Background Cryostat with Dual-Channel Temperature Control for In Situ Neutron Scattering of Rechargeable Batteries

Abstract: In situ neutron scattering enables direct observation of structural evolution in rechargeable battery materials under realistic electrochemical operating conditions. However, existing sample environments often face challenges in simultaneously achieving low neutron-scattering background, precise temperature control, and reliable in situ electrochemical measurements. To address these challenges, we developed a cryostat that integrates a low-background structural design with a dual-channel temperature-control strategy for in situ neutron scattering studies of rechargeable batteries, covering an operating temperature range of 223.15--473.15 K. Finite-element simulations were performed to compare the single- and dual-channel temperature-control strategies and evaluate the resulting temperature distribution and uniformity within the battery region. The results demonstrate that the dual-channel strategy effectively suppresses thermal gradients and significantly improves temperature uniformity. Experimental characterization further demonstrated the temperature control accuracy, long-term operational stability, electrochemical compatibility, and low-background performance of the cryostat. The cryostat provides a reliable sample environment for temperature-dependent in situ neutron scattering studies of rechargeable batteries and offers a practical design reference for the development of advanced neutron-scattering sample environments.