Page 339 - Polymer-based Nanocomposites for Energy and Environmental Applications

306 Polymer-based Nanocomposites for Energy and Environmental Applications

remarkable characteristics that are the keys for the advancement of electrochemical
energy storage technologies.
The design of innovative electrode materials and polymer electrolytes with high
Li + conductivities is among the exciting possibilities offered by polymer
nanocomposites, although optimization of individual component is technical chal-
lenging. The interaction between the filler and the polymer host is to be understood.
Theoretical and experimental studies on transport parameters such as ion mobility and
ion transport correlation and morphology are needed. Migration of nanoparticles at the
electrode/electrolyte interfaces and the interface stabilization are to be addressed
toward enhancing the properties of electrolytes for either high-voltage lithium-ion
or lithium-metal batteries.
An emerging area that takes advantage of the nanomaterial fabrication is the
bottom-up synthesis of freestanding electrodes in which the current collector, the
binder, and the electrochemically active materials are all part of a homogeneous
multicomponent system, which enables synergistic benefits deriving from each
component. For an ideal electrode design, including the coating process, electrode
structure, and mechanical properties, rheological studies and thermal analysis of
the nanocomposite slurries are essential. In this field, the compatibility of low-cost
binders with environmentally friendly solvents is under development for high-
capacity electrode materials such as silicon.
Post lithium-ion technologies need comprehensive studies enabling the construc-
tion of laboratory-scale prototypes especially when metal-air cells and multivalent
ions are considered. Among others, the LidS cell is at present in a much more
advanced stage of development with energies of about 400 Wh kg 1 demonstrated
at cell level [115], which attracts numerous investment from companies such as
Samsung SDI Co. Ltd., BASF Se, Oxis Energy Limited, Robert Bosch Gmbh, and
Polyplus Battery Company. Recent calculations have shown that the main advantage
0
of Li-S batteries compared with LIBs (Li ) is the gravimetric energy density for
lightweight applications [116]. Important aspects to be considered while designing
high-energy-density Li-S batteries are related to the type and areal capacity of
electrolytes. Polymer electrolyte cells showed much higher gravimetric energy
density than the ceramic cells for the same electrolyte thickness and areal capacity
and similarly in comparison with liquid cells. In order to achieve higher energy density
1
than that of the state-of-the-art LIBs (above 271 Wh kg ), areal capacity and
electrolyte thickness have to be carefully designed. However, polymer cells have more
potential and feasibility to achieve higher energy density than liquid and ceramic
systems; this is combined with high safety.

References

[1] Reddy MV, Subba Rao GV, Chowdari BVR. Metal oxides and oxysalts as anode mate-
rials for Li ion batteries. Chem Rev 2013;113(7):5364–457.
[2] Bubnova O, Khan ZU, Malti A, Braun S, Fahlman M, Berggren M, et al. Optimi-
zation of the thermoelectric figure of merit in the conducting polymer poly
(3,4-ethylenedioxythiophene). Nat Mater 2011;10(6):429–33.