2 research outputs found
High energy and high power primary Li-CF batteries enabled by the combined effects of the binder and the electrolyte
Several effective methods have been developed recently to demonstrate
simultaneous high energy and high power density in Li - carbon fluoride
(CF) batteries. These methods can achieve as high as 1000 Wh/kg energy
density at 60-70 kW/kg power density (40-50 C rate) in coin cells and 750 Wh/kg
energy density at 12.5 kW/kg power density (20 C rate) in pouch cells. This
performance is made possible by ingenious nano-architecture design, controlled
porosity, boron doping and electrolyte additives. In the present study, we show
that a similarly great performance, 931 Wh/kg energy density at 59 kW/kg power
density, can be achieved by using a polyacrylonitrile binder and a LiBF4
electrolyte in Li - graphite fluoride coin cells. We also demonstrate that the
observed effect is the result of the right combination of the binder and the
electrolyte. We propose that the mechanistic origin of the observed phenomena
is an electro-catalytic effect by the polyacrylonitrile binder. While our
proposed method has a competitive performance, it also offers a simple
implementation and a scalable production of high energy and high power primary
Li-CF cells.Comment: 13 pages, 8 figures, 1 tabl
Teflon: A Decisive Additive in Directly Fabricating Hierarchical Porous Carbon with Network Structure from Natural Leaf
Hierarchically porous
carbons are of increasing importance due
to their special physicochemical properties. The state-of-the-art
approaches for synthesizing hierarchical porous carbon with network
structure normally suffer from specific chemistries, rigid reaction
conditions, high cost, and multiple tedious steps that limit their
large scale production. Herein, we present an interesting insight
into the important role of Teflon additive in fabrication of hierarchical
porous carbon derived from biomass and, thus, use natural Indicalamus
leaves for the first time to successfully synthesize hierarchical
porous carbon with a three-dimensional morphology of interconnected
nanoparticle units by using a facile and post-treatment-free carbonization
technique. It is surprisingly found that the addition of Teflon not
only reduces the synthesis procedure by combining post-removal of
silica and carbonization in a single step but also plays a decisive
role in generating the hierarchical carbonaceous network structure
with a specific surface area as high as 1609 m<sup>2</sup>/g without
any extra activation procedures. Benefiting from the combination of
well-developed porosity and valuable hierarchical porous morphology,
this type of hierarchical porous carbon has demonstrated attractive
liquid-phase adsorption properties toward organic molecules