1 research outputs found
Single-Shell Multiple-Core MnO@C Hollow Carbon Nanospheres for Low-Temperature Lithium Storage
Lithium-ion
batteries (LIBs) have been extensively employed in
a range of electrical vehicles and portable devices in virtue of their
high energy density and stable cycle life. However, poor performance
under low temperatures hinders their application in cold climates
and regions. Herein, single-shell (carbon) multiple-core (ultra-small
MnO@C nanoparticles) hollow carbon nanospheres (MnO@C@HCS) were prepared
by a sacrificial template method, and MnO@C@HCS showed excellent low-temperature
electrochemical performance. These MnO@C cores with large surface
areas can shorten diffusion lengths of lithium ions and enhance diffusion
rates along their rich grain boundaries, enabling rapid charging/discharging.
The hollow carbon nanosphere with a porous shell can block serious
agglomeration of nanoparticles and regulate the amount of electrolyte
filled in the hollow nanosphere to reduce side reactions between highly
active electrode materials and electrolytes. The hollow structure
formed between the core and the shell mitigates the volume expansion
and contraction during cycling. The MnO@C@HCS anode exhibits high
specific capacities (1027 mAh g–1 at 0.20 A g–1) and high rate performance (353 mAh g–1 at 10.00 A g–1) under room temperature. Furthermore,
the MnO@C@HCS anode maintains a satisfactory discharge capacity under
low temperatures (461 mAh g–1 at 0.05 A g–1 under −10 °C, 220 mAh g–1 at 0.10
A g–1 under −20 °C, respectively). The
contribution of pseudocapacitance to the capacity decreases as the
test temperature drops. Our strategy provides a design concept for
the high-performance anode for low-temperature lithium storage