Most electric vehicles use electricity to power their electric motor via a battery system. But did you know that using hydrogen fuel cells (i.e. a combination of hydrogen and oxygen to produce electricity) to power an electric motor can offer significant advantages? Electric vehicles using hydrogen fuel cells are more efficient than conventional internal combustion engine (ICE) vehicles; they can be refueled in three to five minutes with a range of + 500 km on a single tank and they only emit heat and water. This is definitely a zero‑emission technology not to be ignored!
However, cost, durability and the availability of hydrogen refueling infrastructure are still challenges to overcome to enable the commercialization of fuel cell electric vehicles (FCEV). As a result, the need for a cost‑competitive technology that meets the requirements for high‑volume commercial markets is very pertinent.
With this in mind, a team of researchers at the National Research Council of Canada (NRC) developed a cost‑effective process for polymer electrolytes fabrication, an essential component in proton exchange membrane fuel cells (PEMFC), the technology used in FCEV.
Using an innovative manufacturing approach to make proton exchange electrolyte materials, NRC team lead and senior research officer Asmae Mokrini developed a new process for the fabrication of polymer electrolytes using melt‑blowing technology.
What is melt‑blowing technology? It's a unique, one‑step process in which a thermoplastic polymer is heated in an extruder and then extruded through a circular die. Air is blown into the centre of the extruded tube and induces polymer expansion in the radial direction. Extension of the melt in both the radial and down‑stream directions stops at the frost line due to crystallization of the melt. The nip rolls collecting the film serve as sealing on the top of the bubble to maintain the air pressure inside. This process is used extensively in the film and membrane industry, but has never been applied to high‑value functional polymers. Furthermore, the NRC's process, combined with the use of selected additives, allows the manufacturing of proton‑exchange membranes in their protonated form, therefore there is no requirements for harsh chemical post treatment to reinstate the proton exchange groups.
A techno‑economic cost modelling (TCM) study was used assess the economics of production scale‑up of the NRC's new technology, and to analyze the feasibility of commercialization. Results were compared with state‑of‑the‑art processes and showed that the US Department of Energy's (DOE) cost target of $20/m2 is achievable with the NRC's process at a remarkably low production rate of 30,000 FCEV per year.
In summary, this means that a cost reduction of 60 to 80% for all annual production rate scenarios can be expected.
Long descripion of Cost Analysis of NRC's PEM Manufacturing
Actual cost Nafion® XL, Nafion® 211, Nafion® HP (Ion Power Inc.)
In addition, another advantage to the NRC's proton exchange membrane (PEM) manufacturing technology is that the membranes generated are self‑reinforced and have unique properties regarding water uptake, excellent mechanical properties and durability.
In fact, fuel cell prototypes have been assembled and tested in 2018 according to automotive durability tests (ADT) and achieved over 80,000 cycles. These impressive results were compared to benchmarks prepared by solution‑casting processes (13,000 cycles), and reinforced solution casts (34,000 cycles). NRC researchers continue to actively work with partners on the development of this manufacturing process with advanced PEM materials to optimize production and meet requirements to achieve commercial markets. With a full technology patent in 5 countries (Canada, US, Germany, Japan and Korea), they are actively looking for business opportunities to transfer the technology for licensing and/or collaboration for further industrial development.
More electric vehicles on the roads can certainly help to reduce CO2 emissions globally. The NRC conducts advanced research to support the automotive industry in adopting new electric propulsion technologies and to meet increased consumer demand for more reliable, safe and environmentally responsible vehicles.