# Hydrogen high pressure thermoplastic composite pressure vessel behaviour during a fire

Stéphane Villalonga, Bruno Fournel, Clément Haméon, Joël Toulc’Hoat

► To cite this version:

Stéphane Villalonga, Bruno Fournel, Clément Haméon, Joël Toulc’Hoat. Hydrogen high pressure thermoplastic composite pressure vessel behaviour during a fire. ICHS 2025 - The 11th international conference on hydrogen safety, Hysafe, Sep 2025, Seoul, South Korea. hal-05469763

HAL Id: hal-05469763

https://hal.science/hal-05469763v1

Submitted on 21 Jan 2026

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Distributed under a Creative Commons CC BY 4.0 - Attribution - International License
# HYDROGEN HIGH PRESSURE THERMOPLASTIC COMPOSITE PRESSURE VESSEL BEHAVIOUR DURING A FIRE

Stéphane VILLALONGA

ICHS 2025, Seoul, 23rd of September

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<figure><img src="image_4.png" /></figure>
LD fire duration
30 minutes without rescue

<figure><img src="image_5.png" /></figure>
CPV Final filling state
87.5 MPa, 85°C

<figure><img src="image_6.png" /></figure>
# 70 MPa Type IV H₂ Composite Pressure Vessel (CPV)

<figure><img src="image_7.png" /></figure>

* Metallic boss (AL)

* Plastic liner (PE, PA)

* Composite shell (CF+TS or CF+TP)

AL: Aluminium

PE: Polyethylene

PA: Polyamide

CF: Carbon Fibre

TS: ThermoSet polymer

TP: ThermoPlastic polymer

<figure><img src="image_8.png" /></figure>

Carbon fibre mass = 70% Composite mass

* 1 tow of 24k filaments
  7µm filament diameter

<figure><img src="image_9.png" /></figure>

thermoplastic powder (PE, PA)

<figure><img src="image_10.png" /></figure>

Epoxy resin (TS)
or
PA (TP)
<figure><img src="image_11.png" /></figure>

# Agenda

1. CEA

2. Four 70 MPa CPVs and Three fire test facilities

3. **TS** CPVs behaviour during a fire **without TPRD & without fire protection coating**

4. **TP** CPVs behaviour during a fire **without TPRD & without fire protection coating**

5. **TS & TP** CPVs behaviour during a fire **without TPRD & with CEA fire protection coating**

6. Conclusion

CPV: Composite Pressure Vessel

TS: Thermoset

TP: Thermoplastic
# 1. CEA
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* CEA, the world's leading research institution, ranked among the Clarivate 2025 Top 100 innovators

* The CEA is active in four main areas:

* low-carbon energies

* defense and security

* information technologies

* health technologies

* 9 research centres

* 20 000 technicians, engineers, researchers and staff

* 1 400 PhD & Post Doc

* 750 priority patents filed / year

* 200 start-ups since 1972 in the innovative technologies sector

<figure><img src="image_19.png" /></figure>

<table><thead><tr><th>Rank</th><th>Top 100 Global Innovator, 2025</th></tr></thead><tbody><tr><td>1</td><td>Samsung Electronics</td></tr><tr><td>2</td><td>Tencent</td></tr><tr><td>3</td><td>Honda</td></tr><tr><td>4</td><td>Canon</td></tr><tr><td>5</td><td>Toyota</td></tr><tr><td>6</td><td>Epson</td></tr><tr><td>7</td><td>LG Chem</td></tr><tr><td>8</td><td>FUJIFILM</td></tr><tr><td>9</td><td>Huawei</td></tr><tr><td>10</td><td>RTX</td></tr><tr><td>11</td><td>LG Electronics</td></tr><tr><td>12</td><td>BOE Technology</td></tr><tr><td>13</td><td>Mitsubishi Electric</td></tr><tr><td>14</td><td>Panasonic</td></tr><tr><td>15</td><td>Siemens</td></tr><tr><td>16</td><td>Hyundai Motor</td></tr><tr><td>17</td><td>Sony</td></tr><tr><td>18</td><td>TSMC</td></tr><tr><td>19</td><td>SK hynix</td></tr><tr><td>20</td><td>Kia</td></tr><tr><td>21</td><td>Murata Manufacturing</td></tr><tr><td>22</td><td>Qualcomm</td></tr><tr><td>23</td><td>Toshiba</td></tr></tbody></table>

<table><thead><tr><th>Rank</th><th>Top 100 Global Innovator, 2025</th></tr></thead><tbody><tr><td>24</td><td>Fanuc</td></tr><tr><td>25</td><td>Tokyo Electron</td></tr><tr><td>26</td><td>Sumitomo Electric</td></tr><tr><td>27</td><td>General Motors</td></tr><tr><td>28</td><td>Foxconn</td></tr><tr><td>29</td><td>Samsung Electro-Mechanics</td></tr><tr><td>30</td><td>CEA</td></tr><tr><td>31</td><td>Hitachi</td></tr><tr><td>32</td><td>Airbus</td></tr><tr><td>33</td><td>Ericsson</td></tr><tr><td>34</td><td>GE Aerospace</td></tr><tr><td>35</td><td>AUO</td></tr><tr><td>36</td><td>Dow</td></tr><tr><td>37</td><td>MediaTek</td></tr><tr><td>38</td><td>Philips</td></tr><tr><td>39</td><td>DENSO</td></tr><tr><td>40</td><td>Bosch</td></tr><tr><td>41</td><td>Realtek Semiconductor</td></tr><tr><td>42</td><td>Safran</td></tr><tr><td>43</td><td>Applied Materials</td></tr><tr><td>44</td><td>STMicroelectronics</td></tr><tr><td>45</td><td>Wistron</td></tr><tr><td>46</td><td>NTT</td></tr><tr><td>47</td><td>ITRI</td></tr><tr><td>48</td><td>Kyocera</td></tr></tbody></table>

<table><thead><tr><th>Rank</th><th>Top 100 Global Innovator, 2025</th></tr></thead><tbody><tr><td>49</td><td>Volkswagen</td></tr><tr><td>50</td><td>Siemens Energy</td></tr><tr><td>51</td><td>Kioxia</td></tr><tr><td>52</td><td>Fujitsu</td></tr><tr><td>53</td><td>Brother Industries</td></tr><tr><td>54</td><td>Daikin Industries</td></tr><tr><td>55</td><td>Omron</td></tr><tr><td>56</td><td>Philip Morris International</td></tr><tr><td>57</td><td>TDK</td></tr><tr><td>58</td><td>Nidec</td></tr><tr><td>59</td><td>Ricoh</td></tr><tr><td>60</td><td>MHI</td></tr><tr><td>61</td><td>Nitto Denko</td></tr><tr><td>62</td><td>Infineon Technologies</td></tr><tr><td>63</td><td>Yazaki</td></tr><tr><td>64</td><td>Boeing</td></tr><tr><td>65</td><td>Shin-Etsu Chemical</td></tr><tr><td>66</td><td>Swatch Group</td></tr><tr><td>67</td><td>Alphabet</td></tr><tr><td>68</td><td>BASF</td></tr><tr><td>69</td><td>Johnson &amp; Johnson</td></tr><tr><td>70</td><td>Deere &amp; Co</td></tr><tr><td>71</td><td>Screen</td></tr><tr><td>72</td><td>Micron Technology</td></tr><tr><td>73</td><td>Sumitomo Chemical</td></tr><tr><td>74</td><td>Samsung SDI</td></tr></tbody></table>

<table><thead><tr><th>Rank</th><th>Top 100 Global Innovator, 2025</th></tr></thead><tbody><tr><td>75</td><td>Otis</td></tr><tr><td>76</td><td>ABB</td></tr><tr><td>77</td><td>Ant Group</td></tr><tr><td>78</td><td>Coretronic</td></tr><tr><td>79</td><td>ZEISS</td></tr><tr><td>80</td><td>Nanya Technology</td></tr><tr><td>81</td><td>Evonik</td></tr><tr><td>82</td><td>Halliburton</td></tr><tr><td>83</td><td>Nokia</td></tr><tr><td>84</td><td>Honeywell</td></tr><tr><td>85</td><td>Quanta Computer</td></tr><tr><td>86</td><td>Delta Electronics</td></tr><tr><td>87</td><td>Komatsu</td></tr><tr><td>88</td><td>NEC</td></tr><tr><td>89</td><td>Thales</td></tr><tr><td>90</td><td>AAC Technologies</td></tr><tr><td>91</td><td>CATL</td></tr><tr><td>92</td><td>TE Connectivity</td></tr><tr><td>93</td><td>Caterpillar</td></tr><tr><td>94</td><td>CNRS</td></tr><tr><td>95</td><td>ASML</td></tr><tr><td>96</td><td>Asus</td></tr><tr><td>97</td><td>Winbond</td></tr><tr><td>98</td><td>Michelin</td></tr><tr><td>99</td><td>FORVIA</td></tr><tr><td>100</td><td>Emerson</td></tr></tbody></table>

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70 MPa Type IV H₂ CPV R&D Lab at CEA

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Dedicated R&D H2 CPV plateform at CEA

* Materials

* Polymer synthesis (PA6)

* Polymer & Composite : characterisation, ageing

* Design & FE Calculation

* Industrial Processes and Manufacturing (industrial transfer)

* CPV Testing & SHM

ISO Standards, EC79,&R134 Regulations, additional severe condition tests

* Standard & Regulation contribution

(AFNOR, ISO-TC197, EC-SFEM, UNECE-GTR13)

* Teaching in universities, Support for industry

CPV prototyping and testing

<figure><img src="image_23.png" /></figure>
Onboard 70 MPa Type IV H₂ CPV R&D at CEA

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# Current collaborative research R&D projects

## HYPERSTOCK

ANR-22-PEHY-0004

### Materials and Methodologies repository

* Enhancing the security and confidence of hyperbaric solutions

* Providing solutions for the advent of H2 heavy-duty mobility

* Reducing the carbon footprint of reservoirs, including lifecycle analysis

* Increasing the social acceptability of hyperbaric solutions

<figure><img src="image_27.png" /><figcaption>CEA H₂ 36L CPV : Conformable</figcaption></figure>

## ULHYS

ANR-21-CE05-0019-01

### Rotomolding process optimization with Ultrasonic method and simulation

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<figure><img src="image_29.png" /><figcaption>US signal studies and Process simulation during liner rotomolding</figcaption></figure>

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# Rotomolding & Filament Winding at CEA

<figure><img src="image_31.png" /></figure>

## Rotomolding

<figure><img src="image_32.png" /></figure>

## Robotic Filament Winding

<figure><img src="image_33.png" /><figcaption>CEA H₂ 36L CPV : Conformable</figcaption></figure>

<figure><img src="image_34.png" /><figcaption>CEA H₂ 37L CPV : Full thermoplastic</figcaption></figure>

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## CPV testing at CEA

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(c) Hypactor Project [JTI GA 621194]
CEA Impact with pneumatic canon (5kJ)

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2. 4 H₂ 70MPa CPVs & 3 Fire Test facilities
<figure><img src="image_50.png" /></figure>

# 4 H₂ Type IV 70 Mpa CPV without TPRD

#1

<figure><img src="image_51.png" /></figure>

70MPa H₂ 37L CPV : liner PE, composite T700/epoxy without TPRD
Composite thickness: 21mm

#3

<figure><img src="image_52.png" /></figure>

70MPa H₂ 36L CPV : liner PE, composite T700/epoxy without TPRD
Composite thickness: 21mm

#2

<figure><img src="image_53.png" /></figure>

70MPa H₂ 37L CPV : liner PA6, composite T700/PA6 without TPRD
Composite thickness: 37mm

#4

<figure><img src="image_54.png" /></figure>

70MPa H₂ 36L CPV : liner PA6, composite T700/epoxy without TPRD
Composite thickness: 43mm
<figure><img src="image_55.png" /></figure>

#2: 70 MPa TP matrix CPV defect

lack of composite near the base due to the **bulk** of
the fiber placement process dispensing **head**

<figure><img src="image_56.png" /></figure>

#2

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#2

<figure><img src="image_58.png" /></figure>

⇒ Need protection for the bonfire test

⇒ Reduce the maximal initial pressurisation at the begining of the bonfire test (2 initial pressures: 35MPa, 17MPa)

⇒ Reduce the burst pressure during a fire if the burst occurs in this area

<figure><img src="image_59.png" /></figure>
## Vessels #1 & #2 with CEA fire protection

<figure><img src="image_60.png" /><figcaption>#1</figcaption></figure>

<figure><img src="image_61.png" /><figcaption>#2</figcaption></figure>

<figure><img src="image_62.png" /></figure>
# Polymer fire behaviour

<table><thead><tr><th rowspan="2">polymer</th><th>Epoxy</th><th>Poly-amide 6<br>(Nylon 6)</th><th>Poly-ethylene</th></tr><tr><th>EP</th><th>PA6</th><th>PE</th></tr></thead><tbody><tr><td>polymer type</td><td>thermoset</td><td>thermoplastic</td><td>thermoplastic</td></tr><tr><td>melting temperature</td><td>does not melt</td><td>220°C</td><td>130°C</td></tr><tr><td>char formation</td><td>yes</td><td>no</td><td>no</td></tr><tr><td>combustion speed</td><td>slow</td><td>fast</td><td>very fast</td></tr><tr><td>heat resistance</td><td>high</td><td>low</td><td>very low</td></tr><tr><td>fire resistance</td><td>high</td><td>low</td><td>very low</td></tr></tbody></table>

#1

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<table><thead><tr><th></th><th>Epoxy<br>(EP)</th><th>Poly-<br>amide 6<br>(Nylon 6)<br>(PA6)</th><th>Poly-<br>ethylene<br>(PE)</th><th>Carbon<br>Fibre</th><th>6061 Alloy<br>of<br>Aluminium<br>for bosses</th><th>Water</th></tr></thead><tbody><tr><td>Specific Heat<br>Capacity (Cp:<br>J/g/K)</td><td>1.2 - 1.8</td><td>1.67</td><td>2.3</td><td>0.7 - 1.0</td><td>0.9</td><td>4.18</td></tr><tr><td>Water<br>Absorption<br>(100% RH,23°C)</td><td>0.5 - 2%</td><td>8% - 10%</td><td>&lt;0.02%</td><td>0.2%</td><td>Negligible</td><td>N/A</td></tr><tr><td>Heat of<br>Liquefaction<br>(J/g)</td><td>N/A</td><td>188-250<br>J/g</td><td>150-250</td><td>N/A</td><td>N/A</td><td>333</td></tr><tr><td>Heat of<br>Vaporization<br>(J/g)</td><td>N/A</td><td>N/A</td><td>N/A</td><td>N/A</td><td>N/A</td><td>2260</td></tr><tr><td>Density(g/cm³)</td><td>1.1 - 1.4</td><td>1.13</td><td>0.91-0.97</td><td>1.6 - 2.0</td><td>2.7</td><td>1.0</td></tr></tbody></table>

#2

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#3

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#4

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<figure><img src="image_67.png" /></figure>
# 3 Fire test facilities

<figure><img src="image_68.png" /><figcaption>#1</figcaption></figure>

* Fire: pan (0.6x1.2), C7H16, 2.1 MW/m²

* European Regulation ECE 79

* Gallery with forced air ventilation

* and fume extraction

* 590°C within 2 minutes

<figure><img src="image_69.png" /><figcaption>#2</figcaption></figure>

<figure><img src="image_70.png" /></figure>

* Fire: 4 H₂ injectors, 0.1 MW/m²

* "Representative of accidental situation"

* Good fire visibility with H₂ fire

* 800°C within 30 seconds

<figure><img src="image_71.png" /><figcaption>#3</figcaption></figure>

<figure><img src="image_72.png" /></figure>

* Fire: pan of heptane, 4.3 MW/m²

* European Regulation ECE 79

* Gallery with forced air ventilation

* and fume extraction

* 590°C within 2 minutes

<figure><img src="image_73.png" /><figcaption>#4</figcaption></figure>

<figure><img src="image_74.png" /></figure>

<figure><img src="image_75.png" /></figure>
3. TS CPVs fire behaviour
- without TPRD
- without fire protection coating
70 MPa TS CPVs fire behaviour without TPRD

<figure><img src="image_76.png" /><figcaption>Time before burst or leak for H₂ TS CPV without TPRD during an engulfed fire function of initial pressure (bar)</figcaption></figure>
<figure><img src="image_77.png" /></figure>

# TP&TS CPVs Fire behaviour

- without TPRD

- without Fire protection coating
<figure><img src="image_78.png" /></figure>

<figure><img src="image_79.png" /></figure>

ICHS

International Conference
on Hydrogen Safety

Seoul

<figure><img src="image_80.png" /></figure>

Republic of
Korea

<figure><img src="image_81.png" /></figure>

70 MPa TP&TS CPVs fire behaviour without TPRD

<figure><img src="image_82.png" /><figcaption>Time before burst or leak for H₂ TS&TP CPV without TPRD
during an engulfed fire function of initial pressure (bar)</figcaption></figure>
5.
- TS & TP CPVs Fire behaviour
- without TPRD
- with Fire protection coating
70 MPa TP&TS CPVs fire behaviour without TPRD

<figure><img src="image_83.png" /></figure>

<figure><img src="image_84.png" /></figure>

<figure><img src="image_85.png" /></figure>
TS 37L 70 MPa CPV without TPRD and with CEA coating :
Initial pressure 70 MPa

<figure><img src="image_86.png" /></figure>

<figure><img src="image_87.png" /></figure>

<figure><img src="image_88.png" /></figure>

<figure><img src="image_89.png" /></figure>

<figure><img src="image_90.png" /></figure>
TP 37L 70 MPa CPV without TPRD and with CEA coating :
Initial pressure 35 MPa

<figure><img src="image_91.png" /></figure>

<figure><img src="image_92.png" /></figure>

<figure><img src="image_93.png" /></figure>
# 6. Conclusion

<figure><img src="image_94.png" /></figure>
# Conclusion

Without operational TPRD, for 70MPa **TS** CPV with 2.25 burst ratio (=1.8 safety factor)

* TS CPV at 70MPa initial pressure, burst occurs, the fire resistance duration is lower than 400 s

* Leak-Burst transition is around 30MPA ±5

Without operational TPRD, for 70MPa **TP** CPV with 2.25 burst ratio (=1.8 safety factor)

* TP CPVs fire resistance duration seems around two times greater than TS CPVs (due mainly to TP behaviour)

Without operational TPRD, with **CEA fire protection coating**, for 70MPa **TS&TP** CPV with 2.25 burst ratio (=1.8 safety factor)

* CEA fire protection coating being active for approximately 25 minutes

* TS&TP CPVs fire resistance duration is greater than 30 min (LD fire duration)

Expected burst ratio reduction from **2.25 to 2** (=1.8 to 1.6 safety factor)

* The expected reduction of the burst ratio will reduce significantly the fire resistance duration of CPVs.

* If we consider the CPV state at the end of the filling (87.5 MPa, 85°C), it will reduce even more the fire resistance duration

<figure><img src="image_95.png" /></figure>
# Thanks & Acknowledgement

* The audience

* The ICSH

* The Organisation

* The French National Research Agency (ANR: Agence Nationale de la Recherche)

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