Schefer J.,Paul Scherrer Institute |
Keller L.,Paul Scherrer Institute |
Zannatul Y.,University of Rennes 1 |
Paofai S.,University of Rennes 1 |
And 4 more authors.
International Journal of Hydrogen Energy | Year: 2013
We investigated the first charge cycle of LaNi3.6Co 0.7Al0.4Mn0.3 (LaMM) during electrochemical reduction in a 6N KOD (potassium deuteroxide) electrolyte, corresponding to conditions of commercially used batteries by means of in situ neutron powder diffraction. Our measurement allowed to directly analyze the phase range of the α and β phases and the related volume change as a function of the charge transfer. The intercalation of hydrogen was followed in a home-made electrochemical cell, installed on the high intensity neutron powder diffractometer (DMC) at the Swiss continuous spallation neutron source. Compared to previous investigations following mostly in situ charging under pressure (following pressure-composition-temperature isotherms, PCT), our experimental conditions reflect closely the process as used in technical battery applications. Copyright © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Hieber R.,VARTA Microbattery
Electronic Products | Year: 2012
A new rechargeable battery design which offers higher energy density in a more robust package which is easier to assemble has been developed by VARTA Microbattery. The cells feature a new coiled-electrode construction that makes far more efficient use of the space inside the casing, accommodating a greater surface area of electrode per cubic centimeter than conventional stacked-electrode or layered-electrode construction. In order to implement this new coiled-electrode construction, VARTA has implemented advanced coil winding technology that precisely controls the position of the electrodes inside the cell casing. VARTA has also invented a patented 'ILoc' casing construction. The precisely-engineered upper and lower casings slide together securely, eliminating the requirement for a bulky rim and separate sealing material. This ILoc design also enables the cell to operate as a current-interruption device: When the pressure inside the cell rises above a certain level, the upper and lower casings come apart by a small, controlled amount sufficient to break the circuit and shut down the battery.
Hald S.,VARTA Microbattery
New Electronics | Year: 2010
Original equipment manufacturers (OEM) have implemented effective battery authentication in a bid to address the problem of use of counterfeit batteries that leads to rises in warranty claims and product replacement costs, affecting the manufacturer's reputation. Standard cells fail to provide the exact power capacity required by the application, forcing the OEM to compromise either on size designing in a battery pack that is too large or capacity, an inadequate operating time between charges. A battery security mechanism is therefore required that produces a different data stream every time the host challenges it, which can be implemented using standard ICs and proven security algorithms. The most secure forms of challenge-and- respond scheme today implement the SHA-1/HMAC algorithm, widely used for authentication of online banking transactions and Virtual Private Networks.