
212 Ecological Sustainability
VO H V VO H O V overall reaction
2 2
2
+ + ++ + + ++ +
+ + → + + ( ) (4.40)
The cell voltage ranges from 1.0 V discharged to 1.6 V when fully charged.
The VRFB cell specic energy is 15 to 25 Wh/kg depending on the vana-
dium concentration in the electrolytes (Cellstrom 2010). Tokuda et al. (2000)
described the development of a 450 kW VRFB battery system. Their VRFB
battery specications are given in Table 4.9.
Coulombic efciency remained at 95% over 12,000 C/D cycles, voltage ef-
ciency converged on 85%, and energy efciency also fell from approximately
82% to 80% over the 12,000 cycles. An ideal application for ...