Low permeability polybenzimidazole (PBI) gel membranes for redox flow batteries
US11482721B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 2019 |
| Grant date | Oct 25, 2022 |
| Priority date | — |
| Expiry date | Oct 28, 2039 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/50
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Disclosed are redox flow battery membranes, redox flow batteries incorporating the membranes, and methods of forming the membranes. The membranes include a densified polybenzimidazole gel membrane that is capable of incorporating a high liquid content without loss of structure that is formed according to a process that includes in situ hydrolysis of a polyphosphoric acid solvent followed by densification of the gel membrane. The densified membranes are then imbibed with a redox flow battery supporting electrolyte such as sulfuric acid and can operate at very high ionic conductivities of about 50 mS/cm or greater and with low permeability of redox couple ions, e.g. vanadium ions, of about 10−7 cm2/s or less. Redox flow batteries incorporating the membranes can operate at current densities of about 50 mA/cm2 or greater.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.