Development of Spectroelectrochemical Cells for in situ Neutron Reflectometry

Application of precise neutron focusing mirrors for neutron reflectometry: latest results and future prospects

“…As LiCoO 2 cathodes modified by very thin oxide layers with a thickness of several nanometres have been widely established to exhibit superior cycle stability and high rate capability compared with unmodified LiCoO 2 Hirayama, Sonoyama, Abe et al, 2007;Hirayama, Ido et al, 2010), direct observation of the electrochemical interface during battery operation is the key to elucidating the modification mechanism by the oxide layer. This cathode was packed with a custom-made electrochemical cell (Yonemura et al, 2014) and soaked in an electrolyte LiPF 6 solution consisting of a mixture of deuterated ethylene carbonate and deuterated diethyl carbonate, with a counter-electrode made of Li metal in an Ar-substituted glove box. For the pre-conditioning, charge and discharge cycles were repeated three times prior to the measurement, and the voltage was maintained at the open-circuit voltage of the sample, namely 3.9 V, during the measurement.…”

Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex II: Neutron Scattering Instruments

“…Hence, SOFIA is equipped with a sample changer capable of large quantities of samples, for example, 28 substrates with a diameter of 2-inch, for high throughput measurements. To take further advantage of the high-flux beam, SOFIA can change the repetition rate of the neutron pulses for use of a wide wavelength band from 0.2 nm to 1.76 nm by chopping every two neutron pulses, and it is equipped with sample environments for time-slicing measurement such as liquid injection system, temperature-jump system, and potentiometer [102,103]. These enable us to measure structural evolution over time slices of a few seconds to tens of minutes with a wide Q-range in the swelling process of polymer thin film, thermal diffusion by temperature annealing, electrochemical reactions in the charging/discharging process, and so on.…”

Functional materials analysis usingin situandin operandoX-ray and neutron scattering

“…Beyond the crystallographic and local scales, it is also important in lithium-ion battery research to determine the distribution of the charge-carrying lithium ions, both macroscopically and within electrode layers. Again, neutrons are important in this research, since the relatively large coherent neutron scattering from lithium is sufficient for the determination of lithium distributions within thin films and interfacial layers using neutron reflectometry Yonemura et al, 2014). The relatively large neutron absorption cross-section of natural lithium enables neutron depth-profiling (Oudenhoven et al, 2012) and imaging (Nanda et al, 2012;Senyshyn et al, 2012Senyshyn et al, , 2014 to determine macroscopic lithium distributions and concentration profiles within the different components of whole batteries.…”

“…The halfcell of was configured with Cu as the 'counter'-electrode to prevent Li reaction with the electrode, ensuring that all the electrochemical charge could be attributed to the decomposition of the electrolyte and SEI layer formation. Subsequently, Yonemura et al (2014) developed a purpose-built cell for such experiments.…”