Large format electrochemical energy storage device housing and module

Abstract

An assembly includes non-load bearing housings, each housing including several cavities. Each cavity includes a stack of freely stacked electrochemical storage cells in the housings. Each electrochemical storage cell includes an anode electrode, a cathode electrode, and a separator located between the anode electrode and the cathode electrode. The assembly is configured such that pressure applied to the assembly is born by the freely stacked electrochemical storage cells.

What is claimed is: 
     
         1 . An electrochemical device comprising:
 a housing comprising bottom surfaces and interior and exterior walls extending from the bottom surfaces, so as to at least partially define cavities in the housing;   a liquid or gel electrolyte disposed in the cavities;   stacks of electrochemical storage cells, each stack freely standing in one of the cavities and immersed in the electrolyte, each cell comprising:
 an anode; 
 a cathode; and 
 a separator disposed between the anode and the cathode; and 
   a lid disposed on the housing and configured to seal the stacks in the housing,   wherein the housing and lid comprise a flexible material and are configured to compress the stacks when the bottom surfaces and the lid are pressed toward one another.   
     
     
         2 . The electrochemical device of  claim 1 , further comprising:
 electrical busses that electrically connect the cells of each stack in parallel; and   electrical contacts that extend over the interior walls and electrically connect the stacks in series.   
     
     
         3 . The electrochemical device of  claim 2 , further comprising first and second electrical connectors integrated with one of the exterior walls, the first electrical connector configured to receive a positive voltage from one of the stacks, and the second electrical connector configured to receive a negative voltage from a different one of the stacks. 
     
     
         4 . The electrochemical device of  claim 1 , wherein the lid comprising recessed lid cavities respectively configured to contact an upper surface of each stack. 
     
     
         5 . The electrochemical device of  claim 4 , wherein the lid cavities are configured to receive bottom surfaces of cavities of an adjacent electrochemical device, so as to interlock with the adjacent electrochemical device, and wherein non-recessed portions of the lid are configured to be inserted between the cavities of the adjacent electrochemical device. 
     
     
         6 . The electrochemical device of  claim 1 , wherein the lid comprises:
 electrolyte ports configured to receive electrolyte added to the housing; and   caps configured to seal the respective electrolyte ports.   
     
     
         7 . The electrochemical device of  claim 1 , wherein the interior walls comprise through holes fluidly connecting adjacent cavities. 
     
     
         8 . The electrochemical device of  claim 1 , wherein the housing comprises molded plastic. 
     
     
         9 . The electrochemical device of  claim 1 , wherein the housing comprises molded polypropylene. 
     
     
         10 . The electrochemical device of  claim 1 , further comprising:
 aligned central holes located in the housing and the lid and configured to receive a tie rod that extends through the assembly between the chambers;   an upper pressure plate configured to apply pressure to the lid;   a lower pressure plate configured to apply pressure to the bottom surfaces; and   a binding member attached to the upper and lower pressure plates and extending through the aligned holes of the housing and the lid, the binding member configured to compress the upper and lower pressure plates, such that the stacks are compressed by the lid and the bottom wall.   
     
     
         11 . The electrochemical device of  claim 1 , wherein:
 the stacks comprise anode and cathode current collectors disposed between adjacent cells; and   the cells in each stack are arranged such that the cathode current collectors electrically connect the cathode electrodes of adjacent cells, and the anode current collectors electrically connect the anodes of adjacent cells.   
     
     
         12 . The electrochemical device of  claim 11 , further comprising:
 first electrical busses that electrically connect the anode current collectors of respective stacks; and   second electrical busses that electrically connect the cathode current collectors of respective stacks.   
     
     
         13 . The electrochemical device of  claim 1 , wherein the lid comprises a pressure relief valve configured to relieve excess gas pressure inside the housing. 
     
     
         14 . An electrochemical device comprising:
 a housing;   stacks of electrochemical storage cells located in the housing;   electrical busses that electrically connect the cells of each stack in parallel;   electrical contacts that electrically connect the stacks in series;   a first electrical connector extending outside the housing and connected to a positive output of one of the stacks; and   a second electrical connector extending outside the housing and connected to a negative output of a different one of the stacks.   
     
     
         15 . The electrochemical device of  claim 14 , wherein:
 the housing comprises bottom surfaces and interior and exterior walls extending from the bottom surfaces, so as to at least partially define cavities in the housing which contain a liquid or gel electrolyte;   a lid is disposed on the housing to seal the stacks in the housing; and   the electrical contacts extend over the interior walls to electrically connect the stacks in series;   each stack freely stands immersed in the electrolyte in a respective one of the cavities; and   each cell comprises an anode, a cathode, and a separator disposed between the anode and the cathode.   
     
     
         16 . The electrochemical device of  claim 15 , wherein the cells comprise hybrid devices. 
     
     
         17 . The electrochemical device of  claim 15 , wherein the cells comprise battery cells in which the anode electrodes and the cathode electrodes intercalate ions. 
     
     
         18 . A method of assembling an electrochemical device comprising:
 providing a flexible housing comprising bottom surfaces and interior and exterior walls extending from the bottom surfaces, so as to at least partially define cavities in the housing;   providing a liquid or gel electrolyte in the cavities;   providing stacks of free standing electrochemical storage cells immersed in the electrolyte in the respective cavities, each cell comprising an anode, a cathode, and a separator disposed between the anode and the cathode;   providing a flexible lid on the housing to seal the stacks in the housing; and   pressing the bottom surfaces and the lid toward one another to compress the free standing stacks.   
     
     
         19 . The method of  claim 18 , further comprising:
 electrically connecting the cells of each stack in parallel using electrical buses;   electrically connecting the stacks in series using electrical contacts that extend over the interior walls;   connecting a positive output of one of the stacks to a first electrical connector which extends outside the housing; and   connecting a negative output of another one of the stacks to a second electrical connector which extends outside the housing.   
     
     
         20 . The method of  claim 19 , further comprising:
 stacking a second housing containing a plurality of additional stacks of free standing electrochemical storage cells on the lid; and   connecting the first or the second electrical connector to an electrical connector extending outside the second housing.