The potential partner was unnamed but AFC said it has a global reach and is regarded as a world leading manufacturing services company.
A heads of agreement has been signed that spells out of the terms of a manufacturing services contract that also covers process and supply chain optimisation.
AFC is close to completion of its first commercial fuel cell facility, at Stade in Germany, and also has a pipeline of projects in the Middle and Far East.
Its aim is to have 1GW (gigawatt) of capacity installed by the end of 2020.
This year it has signed heads of agreement in Korea, Thailand (with Bangkok Industrial Gas Co) and a memorandum in Dubai with the Carbon Centre of Excellence (Dubai Carbon).
Adam Bond, AFC's chief executive, said he was confident it would be able to close a deal and enable AFC to hit its aggressive growth trajectory.
"Whilst I expect negotiations on a manufacturing services agreement to progress over the coming weeks and months, I believe the signing of the Heads of Agreement is further validation of the global interest being shown in fuel cell technology generally, and specifically in AFC's offering and positioning within this international market."