srep01917-s2

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Supplementary Information
A physical organogel electrolyte: characterized by in situ thermo-irreversible
gelation and single-ion-predominent conduction
Young-Soo Kim, Yoon-Gyo Cho, Dorj Odkhuu, Noejung Park* and Hyun-Kon Song*
Figure S1 | Gelation of 2 wt. % PVA-CN in an electrolyte. (a) 1 M LiPF6 in 1:2 (vol.)
EC:EMC as the base liquid electrolyte. (b and c) The base electrolyte in presence of 2
wt. % PVA-CN just after addition of the polymer (b) and after being stored at room
temperature for 12 h. (d to f) The PVA-CN-containing electrolyte after gelation at 60 oC.
The samples were stored in vials in an upright position (b to d) and in a 45o-tilting
position (e). The self-standing gel electrolyte monolith templated by a cylinder is shown
in (f).
Figure S2 | Elastic behaviour of a cylindrical monolith of the gel electrolyte based
on 2 wt. % PVA-CN in 1 M LiPF6 in 1:2 (vol.) EC:EMC as the base liquid
electrolyte. (a) Schematic of the experiment. (b to d) The shape of the gel before (b)
and during applying pressure (c) and after removing the pressure (d). Also, refer to the
supplementary movie.
Figure S3 | PVA and PAN in 1 M LiPF6 in 1:2 (vol.) EC:EMC. PVA is not solube in
the electrolyte while PAN is soluble. PAN was not gelated after thermal treatment.
Figure S4 | Binding affinity of EC (as the representative solvent molecule) on PVACN, PVA (as the OH-only control) and PAN (as the CN-only control). (a) Binding
energy profile with respect to the distance between EC and the polymers: solid circle =
PVA-CN; open circle = PVA; horizontal dash-dotted line = the calculated binding
energy of PAN at its equilibrium distance. Subscript H indicates hydrogen atom of PVA
backbone or cyanoethyl groups. The equilibrium configurations of PVA and PVA-CN
are indicated by downward and upward arrows, respectively. (b and c) The equilibrium
binding configurations of EC onto PVA (b) and PVA–CN (c). Atoms are depicted as
balls: H = white small, C = gray, O = red and N = blue.
Figure S5 | Rate capability of pouch-type lithium-ion-battery full cells using the
organogel electrolytes based on PVA-CN (gel.ELF+PVA-CN). Liquid electrolytes
(liq.ELF and liq.ELF+Pullulan-CN) are included for comparison. LiCoO2 and graphite
were used as cathode and anode, respectively. The cells were charged at 0.2C
galvanostatically and then at 4.2 V potentiostatically until their current reached 5 % of
0.2C. Then, they were discharged at the indicated C rates. Q = capacity, % relative to a
designed value, 750 mAh.
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