Composite-overwrapped Type IV pressure vessels are the leading hydrogen-storage technology for fuel-cell vehicles and are now deployed commercially by Toyota and Hyundai, yet several barriers continue to prevent mass-market adoption. This review consolidates four interconnected challenges that the existing literature tends to treat in isolation, viz. commercial implementation gaps, micro-mechanical failure mechanisms, end-of-life sustainability and digital-twin monitoring, respectively. We compare production vessels in the Toyota Mirai, Hyundai Nexo and Honda Clarity Fuel Cell against the United States Department of Energy 2025 storage targets; we examine the micro-scale degradation pathways that operate beneath standard burst-pressure qualification, with particular emphasis on hydrogen-induced blistering at the liner–composite interface during rapid depressurisation; we frame recyclability as a circular-economy problem rather than as a single end-of-life event, and propose cascading fibre utilisation and design-for-disassembly as practical responses; and we evaluate the maturity of digital-twin architectures based on fibre Bragg grating and acoustic-emission sensor fusion. The analysis shows that production vessels essentially meet the volumetric target of 40 g/L but fall short of cost and system-level gravimetric goals, that interface blistering is a critical yet poorly characterised lifetime risk, that thermoset matrices remain the principal sustainability bottleneck while thermoplastic alternatives offer a 15%–25% lifecycle-energy benefit when end-of-life credits are included, and that digital-twin readiness is computationally adequate but practically stalled by the absence of standardised sensor and data protocols. Bringing these threads together is important because each challenge constrains the others. Cost reduction is meaningless without a recyclable matrix, monitoring is meaningless without an interface-aware sensing strategy, and lifecycle benefits cannot be claimed without traceable in-service data. The review concludes by identifying thermoplastic matrix development, standardised sensor integration and interface-aware design as the highest-leverage research directions for accelerating safe, sustainable and cost-effective commercialisation of Type IV hydrogen storage. • Production Type IV vessels meet 40 g/L volumetric target but reach only 4.2 wt% gravimetric, 76% of DOE 2025. • Hydrogen-induced blistering at the liner-composite interface is a critical, poorly characterised lifetime risk. • Hygrothermal ageing reduces interlaminar shear strength of the fibre–matrix interface by 30%–50%. • Thermoplastic matrices deliver 15%–25% lifecycle-energy benefit when end-of-life credits are counted. • Reduced-order digital twins achieve sub-1% deviation from full FEA at 53× speedup, enabling real-time monitoring during fast-fill.
Sanan H. Khan (2026) studied this question.