Explosion free in any fire self-venting (TPRD-less) composite tanks: fundamentals and manufacturing guidance

The rupture of high-pressure hydrogen storage tanks in fires is a critical safety concern that
undermines public confidence and restricts wider deployment of hydrogen technologies.
Current safety strategies depend on thermally activated pressure relief devices (TPRDs),
which have their disadvantages that can lead to critical consequences, for example failing to
react in localised or low-intensity fires and creating additional hazards through high-pressure
hydrogen release. This position paper introduces a breakthrough safety concept: explosion-free, self-venting composite tanks that remain safe under any fire scenario. Based
on the microleaks-no-burst (μLNB) principle, these tanks eliminate the need for TPRDs
by releasing hydrogen through distributed microchannels when exposed to fire. Prototype
testing under both realistic and extreme conditions, including impinging hydrogen jet fires
with heat release rates well beyond standard protocols, has validated the concept. Results
confirm that self-venting tanks prevent rupture, blast waves, fireballs, and pressure peaking,
thereby ensuring inherently safer performance across transport and stationary applications.
Key challenges remain in advancing this technology, including composite-liner compatibility,
thermal degradation, hydrogen permeability, sealing reliability and scaling to larger tanks. Existing test methods lack standardisation and often fail to represent real-world conditions, so
underscoring the need for advanced fire testing protocols. Promising results were achieved
with different fibre-resin composites and liners, however Type V tanks remain at low TRLs.
Further opportunities include the use of thermoplastic materials for circular manufacturing
and recycling. Addressing these gaps through coordinated research will accelerate industrial
adoption, positioning self-venting tanks as a transformative advancement in hydrogen safety, regulation and sustainability.