Hydrogen storage unit

Abstract

A hydrogen vessel comprising a fluid communication port, an outer vessel and an inner compartment. The inner vessel contains a hydrogen storage material, such as a metal hydride. In one embodiment the inner vessel is mechanically isolated from the outer vessel. The separation between the outer and inner vessel provides a peripheral volume between each vessel. The peripheral volume about the inner compartment may be fluidly isolated from the inner compartment. The hydrogen storage unit further includes a fluid pressure device in communication with the peripheral volume; and a controller for controlling the fluid pressure device during desorption and absorption.

1 . A hydrogen storage unit including:
 a fluid communication port;   an outer vessel including an outer vessel wall; and   an inner compartment for hydrogen storage material in fluid communication with the fluid communication port, the inner compartment being spaced from the outer vessel wall to define a peripheral space between the inner compartment and outer vessel wall,   wherein the inner compartment is in fluid communication with the peripheral volume.   
     
     
         2 . The hydrogen storage unit of  claim 1  wherein the inner compartment contains the hydrogen storage-material: the outer vessel surrounding at least a substantial portion of the compartment and spaced therefrom to define the peripheral volume. 
     
     
         3 . The hydrogen storage unit of  claim 2  wherein the inner compartment includes a compartment wall and end pieces, the end pieces engaging the outer vessel wall to support the inner compartment within the outer vessel. 
     
     
         4 . The hydrogen storage unit of  claim 3  wherein the inner compartment is supported in the outer vessel at the end pieces only. 
     
     
         5 . The hydrogen storage device of  claim 2  wherein the fluid communication port is configured to at least substantially bypass the peripheral volume. 
     
     
         6 . The hydrogen storage unit of  claim 1  wherein the inner compartment is in fluid communication with the peripheral volume at a location proximal to the fluid communication port. 
     
     
         7 . The hydrogen storage unit of  claim 1 , the inner compartment being substantially cylindrical, the outer vessel surrounding substantially all of the compartment and having a substantially cylindrical interior whereby the peripheral volume is an annular space. 
     
     
         8 . The hydrogen storage unit of  claim 1  wherein the hydrogen storage material includes one or more high temperature metal hydrides. 
     
     
         9 . The hydrogen storage unit of  claim 1  further including at least one heating element for heating the hydrogen storage material to desorb hydrogen from the hydrogen storage material. 
     
     
         10 . The hydrogen storage unit of  claim 9  wherein the heating element includes an electric heating element. 
     
     
         11 . A hydrogen storage unit including:
 a fluid communication port;   an outer vessel including an outer vessel wall; and   an inner compartment for hydrogen storage material in fluid communication with the fluid communication port, the inner compartment being spaced from the outer vessel wall to define a peripheral volume between the inner compartment and outer vessel wall,   the peripheral volume about the inner compartment is fluidly isolated from the inner compartment; the hydrogen storage unit further including   a fluid pressure device in communication with the peripheral volume; and   a controller for controlling the fluid pressure device;   wherein the controller is configured to:   i) reduce the pressure in the peripheral volume during desorption of hydrogen to insulate the inner compartment; and   ii) increase the pressure in the peripheral volume during absorption/adsorption of hydrogen to conduct heat from the inner compartment to the outer vessel wall.   
     
     
         12 . The hydrogen storage unit of  claim 11  wherein the inner compartment includes a compartment wall and end pieces, the end pieces engaging the outer vessel wall to support the inner compartment within the outer vessel. 
     
     
         13 . The hydrogen storage unit of  claim 11  wherein the controller is configured to evacuate the peripheral volume during removal of hydrogen from the hydrogen storage unit. 
     
     
         14 . The hydrogen storage unit of  claim 11  wherein:
 the inner compartment is connected to the peripheral volume by at least one pressure equalising port; and the fluid communication port fluidly communicates with the inner compartment bypassing the peripheral volume. 
 
     
     
         15 . The hydrogen storage device of  claim 4 , wherein the fluid communication port is configured to at least substantially bypass the peripheral volume. 
     
     
         16 . The hydrogen storage unit of  claim 15 , wherein the inner compartment is in fluid communication with the peripheral volume at a location proximal to the fluid communication port. 
     
     
         17 . The hydrogen storage unit of  claim 16 , wherein the inner compartment being substantially cylindrical, the outer vessel surrounding substantially all of the compartment and having a substantially cylindrical interior whereby the peripheral volume is an annular space. 
     
     
         18 . The hydrogen storage unit of  claim 17 , wherein the hydrogen storage material includes one or more high temperature metal hydrides. 
     
     
         19 . The hydrogen storage unit of  claim 18 , further including at least one heating element for heating the hydrogen storage material to desorb hydrogen from the hydrogen storage material. 
     
     
         20 . The hydrogen storage unit of  claim 19 , wherein the heating element includes an electric heating element.