FUNDAMENTAL SAFETY FUNDAMENTAL SAFETY TESTING AND ANALYSIS TESTING AND ANALYSIS OF HYDROGEN STORAGE OF HYDROGEN STORAGE MATERIALS & SYSTEMSMATERIALS & SYSTEMS

D. Anton, D. Mosher, W. Lohstroh, M. Fichtner, N. Kuriyama, E. Akiba, R. Chahine, D. Dedrick

Hydrogen StorageHydrogen Storage

Compressed HCompressed H22 Gas Gas– 5-10 ksi pressures in graphite fiber reinforced epoxy 5-10 ksi pressures in graphite fiber reinforced epoxy

composite tankscomposite tanks Cryogenic Liquid HCryogenic Liquid H22

– Ambient pressure ultra-insulated containers with Ambient pressure ultra-insulated containers with bleed off devicebleed off device

Compressed/Cryogenic HCompressed/Cryogenic H22– Cryogenic Liquid HCryogenic Liquid H22 in a high pressure tank to in a high pressure tank to

minimize boil-off minimize boil-off AdsorptionAdsorption

– Utilizes physisorption on ultra-high surface Utilizes physisorption on ultra-high surface area species. Currently used at LN2 area species. Currently used at LN2 temperatures.temperatures.

Absorption Absorption – Utilizes chemisorption in metal, organic or Utilizes chemisorption in metal, organic or

complex compoundscomplex compounds

Typical Chemisorption Typical Chemisorption ReactionsReactions

LaNi5H6 LaNi5 + 3H2 Mg2NiH4 Mg2Ni + 2H2

Metal Hydrides

NaAlH4 1/3Na3AlH6 + 2/3Al + H2 NaH + Al + 3H2 Complex Metal Hydrides

2LiBH4 + MgH2 2LiH + MgB + 4H2

8LiH + 3Mg(NH2)2 Mg3N2 + 4Li2NH + 8H2

Destabilized Complex Metal Hydrides

AlH3 Al + 3/2H2NH3BH3 BiNjHk + xH2 Chemical Hydrides

US-DoE Technical US-DoE Technical TargetsTargets

TargetTarget 20072007 20102010 20152015Wt % H2 (Useable) 4.5 6 9

Vol. Cap. (kg H2/L) 0.036 0.045 .081

Cycles 500 1000 1500

Minimum rate (g/s)/kW .02 .02 .02

Minimum/Maximum pressure (atm) [FC]

8/100 4/100 3/100

Minimum/Maximum ambient temperature (°C)

-20/50 -30/50 -40/60

Start time to full flow (s) 4 4 0.5

System fill time (min) 10 3 2.5

Safety Meet or exceed applicable standards

ObjectiveObjective

To To fundamentallyfundamentally understand the safety issues understand the safety issues regarding solid state hydrogen storage regarding solid state hydrogen storage systems through:systems through:

Development & implementation of Development & implementation of internationally recognized internationally recognized standard testing standard testing techniquestechniques to quantitatively evaluate both to quantitatively evaluate both materials and systems. materials and systems.

Determine the fundamentalDetermine the fundamental thermodynamics thermodynamics & chemical& chemical kineticskinetics of environmental reactivity of environmental reactivity of hydrides. of hydrides.

Develop Develop amelioration methods and systemsamelioration methods and systems to to mitigate the risks of using these systems to mitigate the risks of using these systems to acceptable levels. acceptable levels.

Task 1: Standard TestsTask 1: Standard Tests

• FlammabilityFlammability Flammability TestSpontaneous IgnitionBurn Rate

DOT/UN Doc., Recommendations on the Transport of Dangerous Goods, Manual of Tests and Criteria, 3rd Revised

Ed., ISBN 92-1-139068-0, (1999).

• Standard Test Method for Pressure and Rate of Pressure Rise for Combustible Dusts (ASTM E1226)(ASTM E1226)

Pmax & (dP/Dt)max

Min. Exp. Conc.Min. Ignition EnergyMin. Ignition Temp.Min. Dust Layer Ignition Temp.

•Water ContactWater ContactImmersionSurface ExposureWater DropWater Injection

• MechanicalMechanical•Impact•Expansion

Task 2: Thermodynamics Task 2: Thermodynamics & Chemical Kinetics& Chemical Kinetics

Quantitative studies will be performed to understand the chemical kinetics and thermo-chemical release of these reactions with air, oxygen and water as both liquid and vapor as a function of temperature.

Task 3: Risk MitigationTask 3: Risk Mitigation

System risk analyses will be performed and methods of System risk analyses will be performed and methods of mitigating these risks including exposure to air and humidity mitigating these risks including exposure to air and humidity will be investigated. will be investigated.

No

Mitigation

WithMitigation

Task 4: Prototype Task 4: Prototype System TestingSystem Testing

Evaluation tests on risk Evaluation tests on risk mitigations strategies will be mitigations strategies will be performed on sub-scale performed on sub-scale prototype storage systems to prototype storage systems to validate their efficacy. validate their efficacy.

Materials Test PlanMaterials Test Plan

NaAlHNaAlH44+2%TiCl+2%TiCl33 LiH+MgNHLiH+MgNH22

MgMg22NiHNiH44

LaNiLaNi55HH66

NaAlHNaAlH44+2%TiCl+2%TiCl33 LiH+MgNHLiH+MgNH22

MgMg22NiHNiH44

LaNiLaNi55HH66

2LiBH2LiBH44+MgH+MgH22

NHNH33BHBH33

Activated Carbon Activated Carbon AlHAlH33

2LiBH2LiBH44+MgH+MgH22

NHNH33BHBH33

Activated Carbon Activated Carbon AlHAlH33

Use Particle Size & Use Particle Size & PackingPacking

Discharge StateDischarge State– Fully ChargedFully Charged– Partially DischargedPartially Discharged– Fully DischargedFully Discharged

Materials Prep PlanMaterials Prep Plan

UTC 1UTC 1stst Prototype 1kg H Prototype 1kg H22 Storage SystemStorage System

316 SS tubing for ParaTherm MR oil

4% dense aluminum foamwith 50% dense Ti catalyzed

NaAlH4 powder

316 SS liner

316 sintered SS filter

316 SS end closure to facilitate loading and inspection

One end closed carbon fiber composite containment

Rated to 1500psi

Burn Rate TestBurn Rate Test

0 sec. 2.97

6.90 11.09

Partially Discharged CCH#0-33

Water Drop TestWater Drop Test

0 sec. 0.11

0.12 0.15

Partially Discharged CCH#0-33

Water DripWater Drip

0 sec. 0.14

0.17 30.03

Partially Discharged CCH#0-33

Flammability Test Flammability Test Results Results (DOT/UN)(DOT/UN)

Class 4.3,Class 4.3, Packing Group IIPacking Group II

Test Method Ref: 100% 33% 0%UN33.

Prelim. Screening 2.4.3.1 Yes, Flammable Solid Yes, Flammable Solid Yes, Flammable Solid

Burning Rate 2.4.3.2 51 mm/sec 222 mm/sec 27 mm/sec

Burning Rate, 80C Note 1 127 mm/sec spontanious ignition 40 mm/sec

Spontaneous Ignition, R.T. 3.1.4.3 6 Tries, Not Pyrophoric 6 Tries, Not Pyrophoric 6 Tries, Not Pyrophoric

Spontaneous Ignition, 80C Note 1 6 Tries, No Ignition 1 Try, Ignited 6 Tries, No Ignition

Dangerous Self-Heat, 100C 3.1.3.3 Yes, Dangerous Yes, Dangerous Not Dangerous

Dangerous Self-Heat, 120C 3.1.3.3 Not Tested (Note 2) Not Tested (Note 2) Not Dangerous

Dangerous Self-Heat, 140C 3.1.3.3 Not Tested (Note 2) Not Tested (Note 2) Yes, Dangerous

Dangerous When Wet 4.1.4.3 Yes, Class 4.3, Pack Gp 1 Yes, Class 4.3, Pack Gp 1 Yes, Class 4.3, Pack Gp 1Note 1: This is not a UN standard test. We want to know what happens when this material is spilled at operating

temperature of 80C. All other details are per UN burn rate and spontaneous ignition test specifications.

Note 2: This test was not necessary, since this material had already shown dangerous self-heating at 100C.

SAFETY TESTING TABLE OF RESULTS

Air Exposure TestAir Exposure Test

0:00min.

24:05 80oC25:10 smoke observed

26:55 fire 34:15 max fire

Partially Discharged CCH#0-33

Gasoline Burn RateGasoline Burn Rate

0 sec. 0.03

0.75 0.88

Dust Explosion Test Dust Explosion Test ResultsResults(ASTM E1226, E1515, E2019 & (ASTM E1226, E1515, E2019 & E1491)E1491)

Test Materials Reference Materials

NaAlH4 NaH+Al Pitt. Seam Coal Dust

Lycopodium Spores

Pmax bar-g

11.9 8.9 7.3 7.4

Rmax bar/s

3202 1200 426 511

Kst bar-m/s

869 326 124 139

Dust Class

St-3 St-3 St-1 St-1

MEC g/m3

140 90 65 30

MIE mJ <7 <7 110 17

Tc oC 137.5 137.5 584 430

Pmax = maximum explosion pressure, Rmax = pressure rise maximum, Kst = maximum scaled rate of pressure rise, MEC = minimum explosive concentration, MEI = minimum spark ignition energy, Tc = minimum dust cloud ignition temperature

CommunicationCommunication

A WEB site will be established to communicate finding and results to the general public as expeditiously as possible.

ConclusionConclusion

The risks associated with The risks associated with manufacturing, handling, utilization manufacturing, handling, utilization and disposal of solid state hydrides and disposal of solid state hydrides needs to be quantitatively identified.needs to be quantitatively identified.

A thorough risk assessment of solid A thorough risk assessment of solid state hydrogen storage materials and state hydrogen storage materials and systems needs to be performed.systems needs to be performed.

Engineering risk mitigations strategies Engineering risk mitigations strategies need to be identified and tested to need to be identified and tested to bring the risks to tolerable levels for bring the risks to tolerable levels for commercial application.commercial application.