Non-woven fibrous materials and electrodes therefrom

Abstract

Fibrous materials composed of activated carbon fibers and methods for their preparation are described. Electrodes comprising the fibrous materials are also disclosed.

1 . A non-woven fibrous material consisting of activated carbon fiber fragments having substantially similar lengths and diameters, wherein the average aspect ratio of the carbon fiber fragment is between about 1 and 20.  
     
     
         2 . The non-woven fibrous material of  claim 1 , wherein the average aspect ratio of the carbon fiber fragment is between about 1 and 10.  
     
     
         3 . The non-woven fibrous material of  claim 1 , wherein the average aspect ratio of the carbon fiber fragment is between about 1 and 5.  
     
     
         4 . The non-woven fibrous material of  claim 1 , wherein the average aspect ratio of the carbon fiber fragment is between about 2 and 3.  
     
     
         5 . The non-woven fibrous material of  claim 1 , wherein the average diameter of the carbon fiber fragment is less than 15 microns.  
     
     
         6 . The non-woven fibrous material of  claim 1 , wherein the average diameter of the carbon fiber fragment is less than 10 microns.  
     
     
         7 . The non-woven fibrous material of  claim 1 , wherein the average diameter of the carbon fiber fragment is about 5 microns.  
     
     
         8 . The non-woven fibrous material of  claim 1 , wherein the compaction loss is less than 50%.  
     
     
         9 . The non-woven fibrous material of  claim 1 , wherein the compaction loss is less than 40%.  
     
     
         10 . The non-woven fibrous material of  claim 1 , wherein the compaction loss is less than 30%.  
     
     
         11 . A non-woven fibrous material comprising a first population of activated carbon fiber fragments, wherein greater than about 50% of the first population of activated carbon fiber fragments has substantially similar lengths and diameters, and wherein the average aspect ratio of the first population of activated carbon fiber fragments is between 1 and 20.  
     
     
         12 . The non-woven fibrous material of  claim 11 , further comprising at least a second population of activated carbon fiber fragments whose average lengths exceed those of the first population of activated carbon fiber fragments.  
     
     
         13 . The non-woven fibrous material of  claim 11 , wherein the average aspect ratio of the carbon fiber fragment is between about 1 and 10.  
     
     
         14 . The non-woven fibrous material of  claim 11 , wherein the average diameter of the carbon fiber fragment is less than 15 microns.  
     
     
         15 . The non-woven fibrous material of  claim 11 , wherein the average diameter of the carbon fiber fragment is less than 10 microns.  
     
     
         16 . The non-woven fibrous material of  claim 11 , wherein the compaction loss is less than 50%.  
     
     
         17 . An electrode comprising: 
 a current collector; and    a non-woven fibrous layer covering at least a portion of the current collector, wherein the non-woven fibrous layer comprising a first population of activated carbon fiber fragments, wherein greater than about 50% of the first population of activated carbon fiber fragments has substantially similar lengths and diameters, and wherein the average aspect ratio of the first population of activated carbon fiber fragments is between 1 and 20.    
     
     
         18 . The electrode of  claim 17 , wherein the non-woven fibrous layer comprising a first population of activated carbon fiber fragments, wherein greater than about 90% of the first population of activated carbon fiber fragments has substantially similar lengths and diameters, and wherein the average aspect ratio of the first population of activated carbon fiber fragments is between 1 and 20.  
     
     
         19 . The electrode of  claim 17 , wherein the thickness of the non-woven fibrous layer is less than or equal to about 200 micron.  
     
     
         20 . The electrode of  claim 17 , further comprising at least a second population of activated carbon fiber fragments whose average lengths exceed those of the first population of activated carbon fiber fragments.