1. Hydrogen Storage By Michelle Delepine CH 407H

2. Several options Metal Hydride Tanks Compressed Hydrogen Liquid Hydrogen Chemically Stored Hydrogen Carbon Nanotubes Glass Microspheres

3. Metal Hydride Tanks Metallic alloy Absorb H and release later Room temp or heat

4. Metal Hydride Tanks ProsCons  Safe  Constant pressure  Purifies H  No escape potential  Life related to purity Impurities fill tank  Small relative capacity 1-2% of weight 5-7% in 250° C  s

5. Compressed H H is compressed into high-pressure tank Tank material: aluminum or carbon/graphite compounds Liners have reduced leakage

6. Compressed H ProsCons  High energy density  Simple design  Occupies a large space  Would have to be 3,ooo times larger to store as much energy as a gasoline tank  Compression ($)  Held at higher pressures for larger scales of use  High escape potential  Safety checks: Seals

7. Liquefied H Insulated Reinforced

8. Liquefied H ProsCons  Can hold more in less volume than can compressed H  More energy per mass than gasoline  Needs -253°C  Compression and cooling ($)  Energy net loss 30%  Large tank for insulation  Safety (Escape potential)  Depends on tank integrity and temperature

9. Chemically stored H Chemical reaction combines H into stable compound Release H with second reaction

10. Chemically Stored H ProsCons  Most abundant element  Found in numerous chemical compounds  Can use various compounds  Doesn’t need storage tank  Produced on demand  Ammonia cracking  Methanol cracking  Partial oxidation  H cannot be released  Can be bulky and heavy if stored

11. Carbon nanotubes Microscopic carbon tubes (2 nanometers dia) Store H on microscopic pores Similar to metal hydrides

12. Carbon nanotubes ProsCons  Store 4.2-65% of weight  Refuel after 5000 km  Cannot be placed in predetermined positions during manufacturing  Cannot control electrical properties

13. Glass microspheres Tiny hollow glass spheres Warming H gas Cooling locks H inside Warming releases H

14. Glass microspheres ProsCons  Can be very safe  Resist contamination  Can be stored at low pressure  Glass breakage

15. References makes glass permeable releases H Filled by immersing in high- pressure http://www.e- sources.com/hydrogen/storage.html http://www.nanodot.org/article.pl?sid=02/0 8/23/0444204 http://www.eere.energy.gov/hydrogenandfu elcells/pdfs/25106.pdf http://www.eere.energy.gov/hydrogenandfu elcells/storage/compressed_gas.html