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We report on the implementation of a robust and reproducible electrochemical CV (ECV) characterization for the (Al, In)GaN material system. A Schottky‐like contact is formed by electrolyte, wetting the area of the semiconductor surface delimited by a sealing ring. In reverse bias with common CV technique the concentration of donors and acceptors can be evaluated. Using a newly developed etch procedure, which we call “cyclic oxidation”, n‐ and p‐type nitrides can be etched (photo‐)electrochemically (PEC) to yield reproducibly etched surfaces with mirror‐like surface morphology at high etch rates (∼3 μm/h). This new etch procedure is explained in detail. The influence of the process parameters on the etch rate is discussed. Using this new etch procedure, various MOVPE and HVPE grown samples have been characterized by CV‐Profiling. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Reduced safety of conventional organic electrolyte (OE) lithium-ion batteries (LIBs) during abusive failure conditions pose a technical barrier and the state of uncertainty in the market penetration of electrification of vehicles and stationary storage. To address this, we report nonflammable inorganic liquid electrolyte LiFePO4/Graphite (LFP/G) batteries for commercial high energy/power applications. The inorganic electrolyte (IE) is prepared by solvating the molten LiAlCl4 salts using liquid/gaseous xSO2 (x = 1 to 22 moles SO2, proprietary formulae is used) which shows remarkably high Li+ ion conductivity of 121 mS cm−1 at 22 °C. IE LFP/Li half-cell exhibits outstanding rate capability up to 8 C with the capacity of 74 mAh g−1 at room temperature (RT). For the first time, IE-based commercial prototype LFP/G prismatic cells with the capacity of 1.08 Ah shows ultrahigh longevity (50,000 cycles at 2 C up to 20% residual capacity) with coulombic efficiency of ∼99.99% and constant internal resistance at RT. We also demonstrate depth of discharge up to 0 V for 150 cycles using IE LFP/G cells at RT, which shows comparable cycling stability of cells which are discharged to 2.5 V, in contrast to OE LIBs. Further, the capacity retention is improved by 5% using dip-coating process of positive electrodes.

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