Journal of Power Sources, Vol.312, 116-122, 2016
Reduction of charge-transfer resistance at the solid electrolyte -electrode interface by pulsed laser deposition of films from a crystalline Li2PO2N source
Amorphous films deposited by pulsed laser deposition from a crystalline Li2PO2N target in a N-2 ambient atmosphere (LiPON-PLD) have been examined as an approach to reduce the charge-transfer resistance at the electrode-solid electrolyte interface. Despite the relatively low ionic conductivity of ca. 1.5 x 10(-8) S cm(-1) at 25 degrees C, the amorphous LiPON-PLD films deposited between a LiMn1.485Ni0.45Cr0.05O4 (LNM) cathode and LiPON electrolyte resulted in sharply improved electrochemical performance in terms of charge-transfer resistance and CV profiles. Cells without a LiPON-PLD film had a charge-transfer resistance of 4470 Omega-cm(2) compared to 760 and 960 Omega-cm(2) for the sample with 17 nm and 31 nm thick LiPON-PLD films, respectively. The LiPON-PLD amorphous films show no evidence of the continuous planar -P-N-P-N- backbone characteristic of the crystalline target material, but compared with LiPON prepared from radio frequency magnetron sputtering with Li3PO4 in a N-2 atmosphere, the LiPON-PLD films were composed of a higher amount of triply coordinated P - N<(P)(P) with relatively lower contributions of P-N=P. (C) 2016 Elsevier B.V. All rights reserved.