1. Hydrogen Storage and Pressure Increasing
Ma31w203
吳俊儀

2. Hydrogen Storage Methods
High Pressure Tanks
Liquid Hydrogen
Carbon Nanotube Surface Absorbtion
MgH2
NaAlH4

3. Comparison of Methods Method % of Weight Hydrogen Volume 1kg Hydrogen
Hydrogen Gas 200bar
100%
0.06 𝑚 3
Hydrogen Liquid
0.014 𝑚 3
Carbon Nanotube
~6-8%
0.2 𝑚 3
MgH2
7.6%
0.009 𝑚 3
NaAlH4
7.5%(5.6%)
0.01 𝑚 3

4. Where and How Hydrogen be Stored
Hydrogen storage will be required onboard vehicles and at hydrogen production sites, hydrogen refueling stations, and stationary power sites. Possible approaches to storing hydrogen include:
Physical storage of compressed hydrogen gas in high pressure tanks (up to 700 bar);
Physical storage of cryogenic hydrogen (cooled to -253°C, at pressures of bar) in insulated tanks; and
Storage in advanced materials — within the structure or on the surface of certain materials, as well as in the form of chemical compounds that undergo a chemical reaction to release hydrogen.

5. Storage Background Compressed hydrogen dangerous; low energy density
Liquefied hydrogen expensive; cooling and compressing results in loss of 30% of stored energy
Metal hydrides deliver hydrogen safely at constant pressure; sensitive to impurities; store only up to 7 % of its weight
Liquid carrier storage uses fossil fuels as source of hydrogen; defeats purpose of using alternative energy

6. Carbon Nanotubes Stable, lightweight, inexpensive
Large active surface area
Large internal volume if it can be accessed

7. Carbon Nanotubes
Stores hydrogen in pores of microscopic tubes and within tube structures
Similar storage mechanism as metal hydrides
Capable of storing 4.2% to 65% of their own weight in hydrogen

8. Carbon Nanotubes
Carbon Nanotubes
Hydrogen storage in nanotubes