TY - JOUR
T1 - Off-Stoichiometry of Sodium Iron Pyrophosphate as Cathode Materials for Sodium-Ion Batteries with Superior Cycling Stability
AU - Xin, Yuhang
AU - Wang, Yingshuai
AU - Chen, Baorui
AU - Ding, Xiangyu
AU - Jiang, Chunyu
AU - Zhou, Qingbo
AU - Wu, Feng
AU - Gao, Hongcai
N1 - Publisher Copyright:
© 2024 American Chemical Society.
PY - 2024/7/17
Y1 - 2024/7/17
N2 - As one of the important devices for large-scale electrochemical energy storage, sodium-ion batteries have received much attention due to the abundant resources of raw materials. However, whether it is a base station power source, an energy storage power station, or a start-stop power supply, long energy cycle life (more than 5000 cycles), high stability, and safety performance are application prerequisites. Regrettably, currently, few sodium-ion batteries can meet this requirement, mainly due to shortcomings in positive electrode performance. We report a sufficiently stable sodium-ion battery cathode material, Na2Fe0.95P2O7, that retains 97.5% capacity after 5000 charge/discharge cycles. The use of nonstoichiometry in the lattice enables simultaneous modification of the crystal and electronic structure, promoting Na2Fe0.95P2O7 to be extremely stable while still being able to achieve a capacity of 92 mAh g-1 and stable cycling at high temperatures up to 60 °C. Our results confirm the positive effect of nonstoichiometric ratios on the performance of Na2Fe0.95P2O7 and provide a reliable idea to promote the practical application of sodium-ion batteries.
AB - As one of the important devices for large-scale electrochemical energy storage, sodium-ion batteries have received much attention due to the abundant resources of raw materials. However, whether it is a base station power source, an energy storage power station, or a start-stop power supply, long energy cycle life (more than 5000 cycles), high stability, and safety performance are application prerequisites. Regrettably, currently, few sodium-ion batteries can meet this requirement, mainly due to shortcomings in positive electrode performance. We report a sufficiently stable sodium-ion battery cathode material, Na2Fe0.95P2O7, that retains 97.5% capacity after 5000 charge/discharge cycles. The use of nonstoichiometry in the lattice enables simultaneous modification of the crystal and electronic structure, promoting Na2Fe0.95P2O7 to be extremely stable while still being able to achieve a capacity of 92 mAh g-1 and stable cycling at high temperatures up to 60 °C. Our results confirm the positive effect of nonstoichiometric ratios on the performance of Na2Fe0.95P2O7 and provide a reliable idea to promote the practical application of sodium-ion batteries.
KW - cathode material
KW - electrochemical energy storage
KW - large-scale energy storage
KW - sodium-ion batteries
KW - the pyrophosphate structure
UR - http://www.scopus.com/inward/record.url?scp=85199168016&partnerID=8YFLogxK
U2 - 10.1021/acsami.4c08208
DO - 10.1021/acsami.4c08208
M3 - Article
C2 - 38960923
AN - SCOPUS:85199168016
SN - 1944-8244
VL - 16
SP - 36509
EP - 36518
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 28
ER -