Unique electrodes for electrochemical cells
An electrode for electrochemical cells including an electrically conductive cohesive membrane having a thickness defined by a first surface and a second surface opposite the first surface; ohmic impedance independent of membrane thickness; simultaneous uniform charge/discharge throughout membrane thickness; the membrane comprising open cell pores and surfaces; a current collector electrically strongly coupled to the entire membrane thickness; and pins extending through the membrane from the first surface to the second surface; the pins electrically coupled to the current collector having eliminated prior art problematical interfacial layers.
1 . An electrode for electrochemical cells comprising:
an electrically conductive cohesive membrane having a thickness defined by a first surface and a second surface opposite said first surface; said membrane comprising open cell pores and pore surfaces;
a current collector electrically coupled to said pore surfaces; and
pins extending through said membrane from said first surface to said second surface; said pins electrically coupled to said current collector, wherein said pins have an outer surface defining a pin volume, wherein membrane material of said electrically conductive cohesive membrane extends through said pin volume, and wherein pore surfaces of said membrane material within said pin volume are plated with pin material.
2 . The electrode for electrochemical cells according to claim 1 , wherein said membrane comprises one of a nanoscale contiguous open cell pore structure and a mesoscopic contiguous open cell pore structure.
3 . The electrode for electrochemical cells according to claim 1 , wherein said pin material of said pins saturates said membrane open cell pores within said pin volume.
4 . The electrode for electrochemical cells according to claim 1 , wherein each of said pins extend substantially orthogonal from said current collector.
5 . The electrode for electrochemical cells according to claim 1 , wherein said first surface is substantially parallel to said current collector and said second surface is substantially parallel to said current collector.
6 . The electrode for electrochemical cells according to claim 1 , further comprising:
a gap formed between said first surface and said current collector, wherein said first surface is adjacent to said current collector.
7 . The electrode for electrochemical cells according to claim 1 , wherein a bare metal surface of at least one of; the current collector and pins otherwise exposed to electrolyte is coated with a polymer dielectric.
8 . The electrode for electrochemical cells according to claim 1 , wherein said pin material is metal strongly coupled to said pore surfaces within said pin volume.
9 . The electrode for electrochemical cells according to claim 1 , wherein membrane pores outside of said pin volume contain electrolyte.
10 . The electrode for electrochemical cells according to claim 9 , wherein said electrolytes contain either common anions or common cations.
11 . An electrochemical unit cell comprising:
a positive electrode and a negative electrode separated by a separator;
each of said positive electrode and said negative electrode including a galvanic membrane comprising an electrically conducting contiguous open cell porous membrane structure saturated by electrolyte and faradaic or catalyst materials; said galvanic membrane having a thickness defined by a first surface and a second surface opposite said first surface;
a current collector proximate to said first surface; and
pins extending through said membrane from said first surface to said second surface; said pins electrically coupled to said current collector, wherein surfaces of said pins define a pin volume, wherein membrane material of said galvanic membrane extends through said pin volume, and wherein pore surfaces of said membrane material within said pin volume are plated with pin material of said pins.
12 . The electrochemical unit cell according to claim 11 , wherein said separator is selected from the group consisting of an electrolyte/ion permeable dielectric, polymer electrolyte membrane and solid electrolyte.
13 . The electrochemical unit cell according to claim 11 , wherein said pin material of said pins saturates the open cell porous membrane structure within said pin volume.
14 . The electrochemical unit cell according to claim 11 , wherein the pins include a pin base proximate the current collector and a pin top located opposite the pin base proximate the separator.
15 . The electrochemical unit cell according to claim 11 , wherein said galvanic membrane within the pin volume is saturated only with pin material.
16 . A process for forming an electrode for an electrochemical unit cell comprising:
providing an electrically conductive cohesive galvanic membrane having a thickness defined by a first surface and a second surface opposite said first surface; said galvanic membrane comprising open cell pores and pore surfaces;
electrically coupling a current collector to said pore surfaces; and
forming pins extending through said galvanic membrane from said first surface to said second surface, wherein said pins have an outer surface defining a pin volume, and wherein membrane material of said cohesive galvanic membrane extends through said pin volume, and pin material of said pins plates pore surface of said membrane material within said pin volume; and
electrically coupling said pins to said current collector.
17 . The process of claim 16 , wherein said galvanic membrane comprises one of a nanoscale contiguous open cell pore structure and a mesoscopic contiguous open cell pore structure.
18 . The process of claim 16 , wherein said pin material of said pins saturate said galvanic membrane open cell pores within said pin volume.
19 . The process of claim 16 , wherein said membrane material within the pin volume is saturated only with pin material.
20 . The process of claim 16 , further comprising:
forming a gap between said first surface and said current collector.
21 . The process of claim 16 , wherein said galvanic membrane includes a contiguous open cell pore structure that passes unaltered through the pin volume with which the galvanic membrane makes unimpeded metallic contact while the galvanic membrane provides rigidity and strength to the pin.