New lithium iron pyrophosphate as 3.5 V class cathode material for lithium ion battery.
A new pyrophosphate compound Li(2)FeP(2)O(7) was synthesized by a conventional solid-state reaction, and its crystal structure was determined. Its reversible electrode operation at ca. 3.5 V vs Li was identified with the capacity of a one-electron theoretical value of 110 mAh g(-1) even for ca. 1 μm particles without any special efforts such as nanosizing or carbon coating. Li(2)FeP(2)O(7) and its derivatives should provide a new platform for related lithium battery electrode research and could be potential competitors to commercial olivine LiFePO(4), which has been recognized as the most promising positive cathode for a lithium-ion battery system for large-scale applications, such as plug-in hybrid electric vehicles.
Nishimura
Shin-ichi
S
Department of Chemical System Engineering, School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Nakamura
Megumi
M
Natsui
Ryuichi
R
Yamada
Atsuo
A
D011756:Diphosphates / Q000138:chemical synthesis / Q000737:chemistry*; D011211:Electric Power Supplies; D004563:Electrochemistry; D004566:Electrodes; D007501:Iron / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry*; D008958:Models, Molecular
D011756:Diphosphates; D008094:Lithium; D007501:Iron; C049051:ferric pyrophosphate