Abstract:
PROBLEM TO BE SOLVED: To provide systems and methods for accurately characterizing thermodynamic and materials properties of electrodes and of electrochemical energy storage/conversion systems.SOLUTION: Systems 100 and methods are capable of simultaneously collecting a suite of measurements characterizing a plurality of interconnected electrochemical and thermodynamic parameters relating to an electrode reaction state of advancement, voltage and temperature. Enhanced sensitivity provided by the present methods and systems combined with measurement conditions that reflect thermodynamically stabilized electrode conditions enables very accurate measurement of thermodynamic parameters, including state functions such as the Gibbs free energy, enthalpy and entropy of electrode/electrochemical cell reactions, thereby allowing prediction of important performance attributes of electrode materials and electrochemical systems, such as the energy, the power density, the current rate and the cycle life of an electrochemical cell.
Abstract:
Method for rheological characterization of a viscoelastic medium, with the following steps: (a) an excitation step during which a vibratory excitation is generated in the viscoelastic medium leading to a deformation of the medium, (b) a deformation measurement step during which the deformation of the medium caused by the excitation is observed, (c) and a characterization step during which at least one non-zero power parameter y is determined such that a rheological parameter of the medium x is equal to x(f)=a+b·fy, where f is the frequency, a is a real number and b a non-zero scale parameter. It is thus possible to obtain mapping of the power parameter y.
Abstract:
PROBLEM TO BE SOLVED: To provide a method for preparing an at least partially lithiated transition metal oxyanion-based lithium-ion reversible electrode material. SOLUTION: The method for preparing the at least partially lithiated transition metal oxyanion-based lithium-ion reversible electrode material comprises the steps of: providing a precursor of the lithium-ion reversible electrode material; heating the precursor; melting the heated precursor at the temperature sufficient to produce a melt comprising an oxyanion containing a liquid phase; and cooling the melt under such a condition that the solidification of the melt is induced and a solid electrode is obtained which can make possible reversible lithium ion removal/insertion cycles when used in a lithium battery. The lithiated or partially lithiated oxyanion-based lithium-ion reversible electrode material obtained by this process is provided. COPYRIGHT: (C)2010,JPO&INPIT