Hydrogen storage tank and method of using

A method for determining the hydrogen fill level in a hydrogen storage tank containing a solid-state hydrogen storage media, the method comprising:

• equipping the hydrogen storage tank with at least one compartment for storing the storage media, passages for transporting hydrogen gas to the hydrogen storage tank and into the compartment and for transporting hydrogen gas out of the compartment, and means for distributing heat within the compartment so as to establish a substantially uniform temperature in the storage media within the compartment;
• filling the hydrogen storage tank to full capacity by flowing hydrogen gas through the passages and into the compartment so as to adsorb hydrogen on the storage media;
• heating the storage media to a temperature and sensing the pressure of hydrogen gas released from the compartment at the temperature;
• turning on a light source for a time period during which the storage media is at the temperature, the light source generating light at wavelengths to which the storage media is at least partially transparent and at which bonds between hydrogen and the storage media will absorb at least a portion of the light so as to promote the release of hydrogen gas from the storage media;
• sensing a change in the pressure of hydrogen gas released from storage media at the temperature while the light source is on;
• drawing hydrogen gas from the hydrogen storage tank;
• causing hydrogen release from the storage media for a time period during which there is a substantially constant demand on the hydrogen storage tank by turning on the light source;
• measuring a change in pressure of the hydrogen gas released from the storage media during the time period;
• and then
• comparing the measured change in pressure to a look-up table to determine the hydrogen fill level in the hydrogen storage tank, the look-up table being derived from a series of plots relating changes in pressure of the hydrogen gas in the hydrogen storage tank versus fill levels of hydrogen in the hydrogen storage tank as a function of temperature.

A hydrogen storage tank comprising:

• a plurality of separate compartments within the hydrogen storage tank;
• a solid-state hydrogen storage media within the compartments, the storage media being capable of adsorbing and desorbing hydrogen at surfaces thereof;
• passages for transporting hydrogen gas to the hydrogen storage tank and into each of the compartments and for transporting hydrogen gas out of each of the compartments;
• means for distributing heat within and among the compartments so as to establish a substantially uniform temperature in the storage media within the compartments;
• means for desorbing hydrogen from the storage media;
• and
• means for sensing the pressure of hydrogen gas released by desorption from the storage media within the compartments.