Supercapacitor using porous activated carbon cow dung

Patent metadata

Field	Value
Publication number	US-10504662-B2
Application number	US-201816184523-A
Country	US
Kind code	B2
Filing date	Nov 8, 2018
Priority date	Apr 23, 2018
Publication date	Dec 10, 2019
Grant date	Dec 10, 2019

Abstract

The method of making a supercapacitor using porous activated carbon from cow dung includes converting cow dung to porous activated carbon by, in a first step, preparing the dung waste by washing and drying the dung waste, and heating the dung waste in a vacuum environment to form pre-carbonized carbon. In a second step, the pre-carbonized carbon is impregnated with phosphoric acid to form a slurry, which is dried, ground, and heated in a vacuum to between 600-900° C. to form porous activated carbon. The porous activated carbon is mixed with a binder, acetylene black, and an organic solvent to form a paste, which is dried on a conductive metal foil to form an electrode. Two such electrodes (an anode and cathode) to are coated with an electrolyte gel (e.g., aqueous potassium hydroxide) and separated by a polymer (e.g., PTFE) membrane to form the supercapacitor.

First claim

We claim:

1. A supercapacitor, comprising:
an anode and a cathode, the anode and a cathode each having:
a conductive metal foil having an inner side and an outer side;
a terminal attached to the outer side;
a layer of porous activated carbon made from cow dung disposed on the inner side, wherein the layer of porous activated carbon has a specific BET surface area of 2457 m 2 /g with a total pore volume of 1.965 cm 3 /g with a micropore volume of 0.985 cm 3 /g and a mesopore volume of 0.980 cm 3 /g and a specific capacitance of 347 F/g at a small scan rate (5 mV/s); and
an aqueous electrolyte in contact with the layer of porous activated carbon;

a separator disposed between the anode and the cathode, wherein the separator comprises a polymer membrane and the aqueous electrolyte is disposed on the opposite sides of the polymer membrane.

2. The supercapacitor according to claim 1 , wherein said aqueous electrolyte comprises aqueous potassium hydroxide.

3. The supercapacitor according to claim 1 , wherein said aqueous electrolyte comprises an electrolytic gel disposed on the separator.

4. The supercapacitor according to claim 1 , wherein the polymer membrane comprises a membrane made of polytetrafluoroethylene.

5. The supercapacitor according to claim 1 , wherein the conductive metal foil comprises foil made of nickel.

Assignees

• Univ King Saud

Inventors

• Rajabathar Jothi Ramalingam
• Al-Lohedan Hamad Abdullah
• Vijaya Judith J
• Sivachidambaram M

Classifications

• H01G11/34 Primary

  characterised by carbonisation or activation of carbon · CPC title

• H01G11/62

  characterised by the solute, e.g. salts, anions or cations therein · CPC title

• C01B32/324 Primary

  from waste materials, e.g. tyres or spent sulfite pulp liquor · CPC title

• H01G4/38

  Multiple capacitors, i.e. structural combinations of fixed capacitors · CPC title

• H01G11/58

  Liquid electrolytes · CPC title