Charge-discharge capacity and cyclicity of lithium ion battery (LIB) was evaluated in which 15Li
2O·10Fe
2O
3·
xSnO
2·5P
2O
5·(70–
x)V
2O
5 glass (
x?=?0 and 20 in mol%, abbreviated as
xLFSPV) was used as a cathode. A local structure of
xLFSPV glass before and after charging was investigated by
57Fe- and
119Sn-Mössbauer spectroscopies.
57Fe-Mössbauer spectrum of
xLFSPV glass with ‘
x’ of 20 was composed of a doublet with isomer shift (
δ) of 0.35
±0.02 mm s
???1 and quadrupole splitting (
Δ) of 0.88
±0.03 mm s
???1 due to distorted Fe
IIIO
4 tetrahedra.
119Sn-Mössbauer spectrum of this glass consisted of a doublet with
δ of 0.08
±0.01 and
Δ of 0.52
±0.01 mms
???1 due to distorted Sn
VIO
6 octahedra. After discharging the battery from 4.5 to 1.0 V, larger
δ of 0.40
±0.03 mm s
???1 and
Δ of 0.94
±0.04 mm s
???1 were obtained, indicating that both iconicity of Fe-O bonds and local distortion of Fe
IIIO
4 tetrahedra were increased. On the contrary, identical
δ of 0.09
±0.01 mm s
???1 and
Δ of 0.50
±0.01 mm s
???1 were observed in the
119Sn-Mössbauer spectrum of 20LFSPV glass after the discharge, indicating that chemical environment of Sn
IVO
6 octahedra was not affected after the discharge. Charge-discharge curve of LIB containing 20LFSPV glass as a cathode active material recorded under the current density of 8.3 mA g
???1 (0.011 mA cm
???2) between 1.0 and 4.5 V showed a large initial charge capacity of 431.1 mAh g
???1 and discharge capacity of 382.3 mAh g
???1, respectively. These results indicate that 20LFSPV glass could be a new cathode active material for LIB.
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