Hybrid electrochemical cell

Abstract

Disclosed is a hybrid electrochemical cell with a first conductor having at least one portion that is both a first capacitor electrode and a first battery electrode. The hybrid electrochemical cell further includes a second conductor having at least one portion that is a second capacitor electrode and at least one other portion that is a second battery electrode. An electrolyte is in contact with both the first conductor and the second conductor. In some embodiments, the hybrid electrochemical cell further includes a separator between the first conductor and the second conductor to prevent physical contact between the first conductor and the second conductor, while facilitating ion transport between the first conductor and the second conductor.

What is claimed is: 
     
         1 . An electrode comprising:
 a. at least one portion that is a battery electrode;   b. at least one portion that is a capacitor electrode;   c. a ratio between the capacitor electrode and the battery electrode that is from about 1:10 to about 10:1; and   d. graphene formed in an intercorrugated carbon-based network (ICCN).   
     
     
         2 . The electrode of  claim 1 , wherein the electrode comprises an active material deposited on the electrode. 
     
     
         3 . The electrode of  claim 2 , wherein the ICCN comprises the active material in a conformal coating throughout a three-dimensional (3D) structure of the ICCN. 
     
     
         4 . The electrode of  claim 3 , wherein the active material comprises metal oxide particles. 
     
     
         5 . The electrode of  claim 4 , wherein the metal oxide particles comprise niobium pentoxide (Nb 2 O 5 ), lanthanum nickel (LaNi 5 ), cadmium hydroxide (Cd(OH) 2 ), or palladium (Pd). 
     
     
         6 . The electrode of  claim 1 , wherein the capacitor electrode comprises activated carbon. 
     
     
         7 . The electrode of  claim 3 , wherein the capacitor electrode comprises ICCN. 
     
     
         8 . The electrode of  claim 3 , wherein a thickness of the ICCN as measured from cross-sectional scanning electron microscopy (SEM) and profilometry ranges from about 5 μm to about 100 μm. 
     
     
         9 . The electrode of  claim 1 , wherein the ratio between the capacitor electrode and the battery electrode is 1:1. 
     
     
         10 . The electrode of  claim 1 , wherein the ratio between the capacitor electrode and the battery electrode is 2:9, 3:8, 4:7, or 5:6. 
     
     
         11 . The electrode of  claim 1 , wherein the ratio between the capacitor electrode and the battery electrode is 6:5, 7:4, 8:3, or 9:2. 
     
     
         12 . The electrode of  claim 1 , wherein the electrode is configured to function in an electrochemical cell comprising Ni—Cd or Ni-MH chemistry. 
     
     
         13 . The electrode of  claim 1 , wherein the electrode is configured to function in an electrochemical cell comprising lithium ion chemistry. 
     
     
         14 . The electrode of  claim 1 , wherein the electrode is a microelectrode. 
     
     
         15 . The electrode of  claim 2 , wherein the electrode stores charge via adsorption of ions on a surface the electrode.