Electrochemical stack compression system

Abstract

In accordance with one embodiment, an electrochemical cell stack compression system may include an integral, hollow frame configured to contain a plurality of electrochemical cells arranged along an axis in a stack configuration. The frame may have a defined shape and may form a continuous border around a periphery of the electrochemical cell stack when inserted. The frame may be formed of a plurality of fibers.

What is claimed is: 
     
         1 . An electrochemical stack compression system comprising:
 a structure having a defined shape that is configured to receive and contain:   a plurality of electrochemical cells arranged in a series along an axis to form an electrochemical stack; and   at least one compression mechanism configured to apply a compressive force to the electrochemical stack, wherein the compression mechanism is located adjacent to and along the axis of the electrochemical stack;   wherein the structure forms a continuous border surrounding the electrochemical stack and the at least one compression mechanism when contained.   
     
     
         2 . The compression system of  claim 1 , wherein the compression mechanism includes a first gib and a second gib inserted between the stack and an end block, the first and second gibs each having a flat surface and an opposite, angled surface, the flat surface of the first gib lies adjacent the stack, and the angled surface of the second gib is sloped at an angle complimentary to the angled surface of the first gib and is inserted adjacent the angled surface of the first gib. 
     
     
         3 . The compression system of  claim 1 , wherein the compression mechanism includes internal drive screws configured to increase the size of the compression mechanism when the internal drive screws are rotated in a first direction and to decrease the size of the compression mechanism when the internal drive screws are rotated in a second direction opposite the first direction. 
     
     
         4 . The compression system of  claim 1 , wherein the structure is formed of wound fibers constructed of a plurality of discrete layers. 
     
     
         5 . The compression system of  claim 4 , wherein each discrete layer is formed of homogenous fibers. 
     
     
         6 . The compression system of  claim 4 , wherein each discrete layer is formed of a combination of fibers of different materials. 
     
     
         7 . The compression system of  claim 4 , wherein at least two of the discrete layers are attached by bonding or fastening mechanisms. 
     
     
         8 . The compression system of  claim 4 , wherein at least two of the discrete layers are unattached and held in position by fiction. 
     
     
         9 . The compression system of  claim 4 , wherein the frame includes a friction-reducing layer located between at least two of the discrete layers. 
     
     
         10 . The compression system of  claim 4 , wherein at least a portion of the wound fibers are carbon fibers. 
     
     
         11 . The compression system of  claim 4 , wherein the fibers are non-conductive. 
     
     
         12 . The compression system of  claim 1 , wherein the structure has two opposing walls connected by rounded circular ends. 
     
     
         13 . The compression system of  claim 12 , wherein the end block has a rounded surface configured to abut one of the rounded circular ends of the structure. 
     
     
         14 . The compression system of  claim 1 , wherein a height of the structure along the axis of the electrochemical stack changes in response to a load applied by the compression mechanism to the electrochemical stack when containing the compression mechanism. 
     
     
         15 . A method of pre-loading the compression system of  claim 1 , the method comprising:
 inserting the electrochemical stack into the structure;   inserting the at least one compression mechanism into the structure;   configuring the compression mechanism to apply a predetermined load within the compression system; and   measuring a change in height of the structure along the axis of the electrochemical stack to determine the load being applied by the compression mechanism.   
     
     
         16 . The method of  claim 15 , wherein the compression mechanism configuring the compression mechanism includes at least one of wedging the first gib against the second gib, increasing the temperature of the compression system to expand the compression mechanism, or rotating a plurality of internal drive screws to expand the compression mechanism.