Neutral pH Aqueous Redox Flow Battery Materials: BTMAP-Vi, BTMAP-Fc
Redox flow batteries (RFB), which have advantages in terms of size and capacity scalability, have been investigated mainly using inorganic active materials. On the other hand, organic redox flow batteries (ORFB) using organic active materials have also been receiving much attention, particularly because they are comprised of earth-abundant elements. Gordon and Aziz et al. developed the following viologen and ferrocene derivatives as aqueous ORFB materials that also provide high cycling stability.
• Operable at neutral pH
• Reduction potential -0.358 V for BTMAP-Vi, and oxidation potential +0.390 V for BTMAP-Fc (vs SHE)
• High capacity retention (99.9989%/cycle at 0.75-1.00 M)
- A Neutral pH Aqueous Organic–Organometallic Redox Flow Battery with Extremely High Capacity Retention