کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6470148 1424104 2017 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Enhancing electrochemical performance of LiFePO4 by vacuum-infiltration into expanded graphite for aqueous Li-ion capacitors
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Enhancing electrochemical performance of LiFePO4 by vacuum-infiltration into expanded graphite for aqueous Li-ion capacitors
چکیده انگلیسی

Olivine-type LiFePO4 (LFP) is one of the most widely utilized cathode materials for high power Li-ion batteries (LIBs). In spite of rapidly growing popularity of LIBs, the rate performance of the highest power LFP cells is still insufficiently high for some high-power applications. In this work we demonstrate that vacuum-infiltration of LFP precursors into pores of low-cost expanded graphite (EG), an in-situ sol-gel process, followed by calcination, allows formation of LFP/EG nanocomposites that demonstrate remarkable performance in higher power Li-ion capacitor (LIC) applications. Such composites comprise spherical LFP particles embedded into EG pores and additionally wrapped by EG films, forming a highly efficient and stable conducting network. Such a morphology greatly accelerates Li-ion diffusion and improves Li-ion exchange between LFP and electrolyte. As a result, compared to commercial LFP particles of comparable size, the optimized LFP/EG nanocomposite shows significantly higher rate performance, dramatically better stability and higher specific capacitance of up to about 1200 F g−1. The use of environmentally friendly, safe and low-cost aqueous electrolyte is particularly advantageous for LIC applications that are cost-sensitive and require enhanced safety. Our results demonstrate a great promise of our approach, which is additionally applicable for a broad range of other intercalation chemistries.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Electrochimica Acta - Volume 253, 1 November 2017, Pages 413-421
نویسندگان
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