Applications

Fuel Cells for Zero-Emission Transportation (powered by Hydrogen)

Aquivion® ionomers are used in proton exchange membrane fuel cells. Typical applications are anode or cathode binders and thin separator membranes (10-15μm). Aquivion® ionomers have a superior proton conductivity and water retention level at low relative humidity. This, combined with its high glass transition temperature, enables stack operation up to 120°C resulting in smaller front radiators and high-power density stacks.

Syensqo offers a broad portfolio of grades under dispersion product form. 

Key-value Proposition of Aquivion® Ionomer: 

• Superior proton conductivity and water retention enable high power density even at low relative humidity and hence simpler and more compact balance of plant
• High Tg enables stack operation up to ~120°C, allowing smaller front radiators

Recommended Product Forms:

• Dispersions of electrodes: Aquivion® D72-25Bs, N+ 125D/251.612 and X N+100D/251.612
• Dispersions for the manufacturing of Polymer Electrolyte Membranes (PEM): Aquivion® D72-25Bs or D87-28BS (for stationary fuel cells)

Hydrogen Production via Water Electrolysis

Syensqo develops “best in class” materials for Membrane Electrode Assembly water electrolyzer applications.

As a key component of the polymer electrolyte membrane (PEM) water electrolysis cell, a polymer electrolyte membrane with good mechanical, thermal and chemical stability is required. Aquivion® ionomers widen the electrolyzer operating window; higher glass transition and higher levels of crystallinity improve thermal rating and mechanical stability, and reduce the gas crossover.

Furthermore, Aquivion® dispersions are applied as anode and cathode binders, thanks to the wide choice of proton conductivity grades and low catalyst deactivation.   

Key-value Proposition of Aquivion® Ionomer:

• Good mechanical stability at 25% lower thickness leads to lower cell voltage and allows for lower system capex & opex
• High-temperature stability makes it possible to use Aquivion® at temperatures >85°C, reducing cell resistances and increasing system efficiency (less kWh per kg H2)
• High chemical stability allows operating under temporary overload (e.g. for fluctuating RES production) and enlarges the electrolyzer operating window

Recommended Product Form: 

• Dispersions of electrodes: Aquivion® D87-28BS and D72-25BS
• Dispersion for membrane separator manufacturing: Aquivion® D87-28BS and D72-25BS

Redox Flow Batteries (RFBs)

Aquivion® cation-conductive membranes are high-performing core components of redox flow batteries (RFBs).

The ongoing development path towards higher current density operation in RFBs makes Aquivion® membrane the proper fit with a variety of electrolyte configurations.

Key-value Proposition of Aquivion® Ionomer:

• High cation conductivity not only for proton conduction under acid conditions (pH <0~7) but also for Na+/K+ ions under alkaline conditions (pH 7~14);
• High selectivity (low permeability) to prevent passage of the larger redox-active counter-ions crossover of which to the opposite electrolyte would be undesirable.
• Unmatched chemical resistance also in extreme pH solutions for years of service life,
  • be it at pH <0 (e.g. for Vanadium RFBs with acid concentration > 1 mole/l),
  • or at pH ~14 (e.g. organic RFB at high state of charge, soc).

Combination of the above features allows developers to exploit the entire bandwidth between deep discharge (state-of-charge, SOC, ~5%) and full charge (SOC ~95%) without suffering RFB degradation or “memory effects”.  This technical advantage translates into a maximized kWh capacity per amount of electrolyte.

Various RFBs leveraging different posolyte/negolyte combinations have already entered their commercialization stage; with Aquivion® identified as their best-performing membrane resin.

Key Benefits:

• Smaller stacks thanks to unmatched conductivity and very high power density kW/m²
• Lower opex thanks to better membrane selectivity reduces undesired crossover phenomena
• Extended multi-year durability (e.g. in comparison with hydrocarbon-based membrane separator resins) reduces maintenance costs.
• Access to a maximum of the specific electrolyte capacity (kWh per kilogram, or per liter)

Recommended Product Forms: 

• Dispersions: Aquivion® N+125D/251.612 and X N+100D/251.612 for casting of tailor-made types of separator membranes