Volt Carbon Technologies has developed a flexible downstream manufacturing process at its Guelph, Ontario facility capable of converting graphite concentrate into either graphene oxide or expandable graphite using the same processing equipment, and has produced multiple batches of both materials for product trials.
The process operates downstream from Volt's proprietary air classification technology, which dry-separates crushed graphite ore into a graphite concentrate. From that concentrate, the company's new downstream process can be configured to produce either graphene oxide or expandable graphite without requiring two separate processing lines, an approach the company says supports its goal of building a North American supply chain for advanced carbon materials less dependent on foreign sources.
Volt also reported progress on graphene quality. The company previously announced, in October 2025, production of reduced graphene oxide (rGO) at approximately five layers, which improved epoxy test coupon mechanical properties by 40% to 60% over virgin epoxy. Recent XRD characterization performed at University of Waterloo laboratories now indicates the material has been refined to approximately three graphene layers.
On the expandable graphite side, Volt cited earlier third-party testing from July 2024, when ProGraphite GmbH independently tested graphite processed using Volt's dry separation technology on behalf of Green Battery Minerals Inc. and measured an expansion rate of 325 mL/g with approximately 98.5% carbon content after expansion, describing the result as "excellent" for +80 mesh material suitable as an expandable graphite precursor. That figure reflects the graphite precursor's expansion performance from 2024 rather than new testing of the current graphene oxide or expandable graphite batches.
Additional batch-scale production equipment ordered in May 2026 has now arrived at the Guelph facility and is being integrated into Volt's downstream processing line. The company said its current batch-scale graphene output can support meaningful customer trials, since graphene is typically evaluated at low loading levels, with a 0.5% loading in its epoxy testing representing about 5 kg per tonne of finished composite, and even lower loadings under evaluation for applications such as carbon-fiber composites.
"The concept is simple: start with natural graphite and create multiple higher-value products," said V-Bond Lee, CEO of Volt Carbon. "One flexible processing platform can produce either graphene oxide or expandable graphite, and we have now produced multiple batches of both. We have also advanced our graphene from approximately five layers to approximately three layers based on recent XRD characterization at University of Waterloo laboratories. We are continuing to push toward the limits of what can be achieved with natural graphite while developing practical processes that can be scaled and used by customers. There is still a lot of work ahead, but our capabilities continue to improve every day."
