The Short Version
The claim bundles a genuine advantage with an unsupported one. Graphene-based technologies do charge significantly faster than conventional lithium-ion — multiple sources confirm this. However, the assertion of "higher energy density" is contradicted by the best available evidence: the leading graphene aluminium-ion battery (GMG) achieves only 26–101 Wh/kg depending on charge rate, well below lithium-ion's commercial 150–250 Wh/kg range. Even the manufacturer's own disclosures acknowledge this gap. The energy density claim relies on theoretical projections and marketing materials, not demonstrated commercial performance.