Thermal Stabilities of Delithiated Olivine MPO[subscript 4] (M=Fe,Mn) Cathodes investigated using First Principles Calculations
نویسندگان
چکیده
We present an analysis of the thermal reduction of delithiated LiMnPO4 and LiFePO4 based on the quarternary phase diagrams as calculated from first principles. Our results confirm the recent experimental findings that MnPO4 decomposes at a much lower temperature than FePO4, thereby potentially posing larger safety issues for LiMnPO4 cathodes. We find that while substantial oxygen is released as MnPO4 reduces to Mn2P2O7, the mixed valence phases that form in the decomposition process of FePO4 limit the amount of oxygen evolved.
منابع مشابه
Phase diagram and electrochemical properties of mixed olivines from first-principles calculations
Phase diagram and electrochemical properties of mixed olivines from first-principles calculations. Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Using first-prin...
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