Electrochemical cell suitable for use in electronic device

Abstract

An electrochemical cell for a portable electronic device is provided, said cell having a positive electrode, a negative electrode and an electrolyte, characterised in that at least the positive electrode comprises a mesoporous structure having a periodic arrangement of substantially uniformly sized pores of cross-section of the order of 10 −8 to 10 −9 m.

1 . A portable electronic device comprising an electrochemical cell, said cell comprising a positive electrode, a negative electrode and an electrolyte, wherein said positive electrode comprises a mesoporous structure having a periodic arrangement of substantially uniformly sized pores with a cross-section in the order, of 10 −9  to 10 −8  m.  
   
   
       2 . A portable electronic device according to  claim 1 , wherein the mesoporous structure of the positive electrode is a metal, a metal oxide, a metal hydroxide or a combination thereof.  
   
   
       3 . A portable electronic device according to  claim 1 , wherein the mesoporous structure of the positive electrode comprises a metal, a metal oxide, a metal hydroxide or a metal oxy-hydroxide, said metal oxide, metal hydroxide or metal oxy-hydroxide, forming a surface layer over said metal and extending over the pore surfaces.  
   
   
       4 . A portable electronic device according to  claim 1 , wherein the mesoporous structure of the positive electrode comprises a metal that is nickel or nickel alloys.  
   
   
       5 . A portable electronic device according to  claim 1 , wherein said mesoporous structure comprising a metal oxide, hydroxide or oxy-hydroxide is gold oxide; palladium oxide; nickel oxide (NiO); nickel hydroxide (Ni(OH) 2 ), nickel oxy-hydroxide (NiOOH) or ruthenium oxide.  
   
   
       6 . A portable electronic device according to  claim 1 , wherein the mesoporous structure has a pore diameter in the range of about 1 to 10 nm.  
   
   
       7 . A portable electronic device according to  claim 1 , wherein the mesoporous structure has a pore number density of about 4×10 11  to 3×10 13  pores per cm 2 .  
   
   
       8 . A portable electronic device according to  claim 1 , wherein at least 85% of the pores in said mesoporous structure have pore diameters within 30% of the average pore diameter.  
   
   
       9 . A portable electronic device according to  claim 1 , wherein the mesoporous structure has a hexagonal arrangement of pores that are continuous through the thickness of the electrode.  
   
   
       10 . A portable electronic device according to  claim 9 , wherein the hexagonal arrangement of pores has a pore periodicity in the range of 5 to 9 nm.  
   
   
       11 . A portable electronic device according to  claim 1 , wherein the negative electrode comprises a mesoporous structure having a periodic arrangement of substantially uniformly sized pores with a cross-section in the order of 10 −9  to 10 −8  m.  
   
   
       12 . The portable electronic device of  claim 1 , wherein said mesoporous structure is a film having a thickness in the range of about 0.5 to about 5 micrometers.  
   
   
       13 . The portable electronic device of  claim 1 , wherein said negative electrode comprises a material that is carbon, cadmium, iron, a palladium/nickel alloy, an iron/titanium alloy, palladium, or LaNi 5 H x .  
   
   
       14 . The portable electronic device of  claim 1 , wherein said negative electrode comprises a material that is carbon or palladium.  
   
   
       15 . The portable electronic device of  claim 1 , wherein said mesoporous structure comprises nickel and a nickel oxide, a nickel hydroxide or a nickel oxy-hydroxide that is NiO, Ni(OH) 2  and NiOOH, said nickel oxide, nickel hydroxide, or nickel oxy-hydroxide forming a surface layer over said nickel and extending over the pore surfaces, and wherein said negative electrode has a mesoporous structure comprised of carbon or palladium.  
   
   
       16 . The portable electronic device of  claim 15 , wherein said negative electrode comprises nanoparticulate carbon.  
   
   
       17 . The portable electronic device of  claim 1 , wherein said cell is constructed to function as a battery, as a supercapacitor or a combination thereof.  
   
   
       18 . A portable electronic device according to  claim 6 , wherein the mesoporous structure has a pore diameter in the range of about 2.0-8.0 nm.  
   
   
       19 . A portable electronic device according to  claim 7 , wherein the mesoporous structure has a pore number density of 1×10 12  to 1×10 13  pores per cm 2    
   
   
       20 . The portable electronic device of  claim 8 , wherein at least 85% of the pores in said mesoporous structure have pore diameters to within 10% of the average pore diameter.  
   
   
       21 . The portable electronic device of  claim 8 , wherein at least 85% of the pores in said mesoporous structure have pore diameters to within 5% of the average pore diameter.  
   
   
       22 . The portable electronic device of  claim 4 , wherein said Nickel alloys are alloys a transition metal, nickel/cobalt alloys, iron/nickel alloys, cobalt, platinum, palladium or ruthenium.