Ultra-low vanadium ion diffusion amphoteric ion-exchange membranes for all-vanadium redox flow batteries.
作者：Junbin Liao, Meizhen Lu, Youqun Chu, Jianli Wang*
關(guān)鍵字：Fluoro-methyl sulfonated poly(arylene ether ketone)，Amphoteric ion-exchange membrane，Ultra-low vanadium permeability，High Coulombic efficiency，Vanadium redox fl ow battery
論文來源：期刊
具體來源：Journal of Power Sources
發(fā)表時間：2015年
An am photeric ion-exchange membrane (AIEM)
from fluoro-methyl sulfonated poly(arylene ether ketone) bearing
content-controlled benzimidazole moiety, was firstly fabricated for vanadium
redox flow battery ( VRB). The AIEM and its covalently cross-linked
membrane ( AIEM-c) behave the highly suppressed vanadium-ion crossover and
their tested VO2+ permeability are about 638 and 1117 times
lower than that of Nafi- on117, respectively. This is further typically
verified by the lower VO2+ concentration
inside AIEM that is less than half of that
inside Nafion117 detected by energy dispersive X-ray spectrometry, in addition
of the nearly 3 times longer battery self-di scharge time. The ultra-low
vanadium ion diffusion could be ascribed to the narrower ion transporting
channel originated from the acid- base interactions and the rebelling effect
between the positively-charged benzimidazole structure and VO2+ ions.
It is found that, VRB assembled with AIEM exhibits the equal or higher
Coulombic effi ciency (99.0% vs . 96.4%), voltage efficienc y (90.7% vs .
90 .7%) and energy
efficiency (89. 8% vs . 87.4%) than that
with Nafion117 and keeps continuous 220 chargee-discharge cycles for over
25 days, confirming that the AIEM of this type is a potentially suitable
separator for VRB appl ication.© 2015 Elsev ier B.V. Al l rights reserved.
