Hybrid electrochemical energy storage system with high energy density and high power density
The present disclosure pertains to an energy storage device and a method for its fabrication, designed to possess integrated redox and electrostatic attributes. The device encompasses at least a pair of positive electrode ( 5,7 ) and negative electrode ( 1,3 ). The negative electrode ( 1,3 ) is coated with different active materials in varying thickness. The Positive electrode ( 5,7 ) is coated with an active cathode material ( 7 ) on one side, combination of capacitive material along with active cathode material ( 5 ) on other side of the electrode resulting in high energy density and high power density. Porous trilayer separator ( 4 ) is placed to physically isolate the electrodes from each other. The electrode pair be configured in a rolled formation to form a cylindrical geometry.
1. An electrochemical energy cell, comprising:
a. a positive electrode comprising a first current collector substrate made of aluminium,
wherein a first side of said first current collector substrate is coated with a first material comprising a combination of a battery cathode material and a supercapacitor material, wherein said battery cathode material is 60-95% NMC 811 and said supercapacitor material is 35-80% activated carbon,
wherein a second side of said first current collector substrate is coated with a second material comprising said battery cathode material, and
wherein said coating on said second side of said first current collector substrate is thicker than said coating on said first side of said first current collector substrate;
b. a negative electrode comprising a second current collector substrate made of copper,
wherein a first side of said second current collector substrate is coated with a third material comprising silicon-graphite and a second side of said second current collector substrate is coated with a fourth material comprising graphite, wherein said third material comprising 70-95% silicon-graphite and said fourth material comprising 70-95% graphite, and
wherein said coating on said first side of said second current collector substrate is thicker than said coating on said second side of said second current collector substrate; and
c. a first porous separator layer disposed between said positive electrode and said negative electrode, wherein a first side of said first porous separator layer facing said first side of said first current collector substrate and a second side of said first porous separator layer facing said second side of said second current collector substrate.
2. The electrochemical energy cell as claimed in claim 1 , wherein said first porous separator layer is a trilaminate separator.
3. The electrochemical energy cell as claimed in claim 2 , wherein said cell further comprising an electrolyte and a second porous separator layer, wherein said second porous separator layer facing said second side of said first current collector substrate.
4. The electrochemical energy cell as claimed in claim 2 , wherein said trilaminate separator comprises of a first polypropylene layer, a polyethylene layer, and a second polypropylene layer.