US 11,791,479 B2
Methods and system for manufacturing a redox flow battery system by roll-to-roll processing
Yang Song, West Linn, OR (US); and Craig E. Evans, West Linn, OR (US)
Assigned to ESS TECH, INC., Wilsonville, OR (US)
Filed by ESS TECH, INC., Wilsonville, OR (US)
Filed on Aug. 8, 2019, as Appl. No. 16/536,259.
Claims priority of provisional application 62/717,633, filed on Aug. 10, 2018.
Prior Publication US 2020/0052310 A1, Feb. 13, 2020
This patent is subject to a terminal disclaimer.
Int. Cl. H01M 8/0254 (2016.01); H01M 8/18 (2006.01); H01M 8/0215 (2016.01); H01M 8/0221 (2016.01); H01M 8/0226 (2016.01)
CPC H01M 8/0254 (2013.01) [H01M 8/0215 (2013.01); H01M 8/0221 (2013.01); H01M 8/0226 (2013.01); H01M 8/188 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method for manufacturing a redox flow battery, comprising:
combining and treating chemical ingredients configured to form a sheet of a membrane separator via a first roll-to-roll calendering process, the first roll-to-roll calendering process comprising:
forming the sheet from the combined chemical ingredients;
molding ribs onto a surface of the sheet, the ribs extending along a vertical axis of the membrane separator relative to placement of the membrane separator within a negative electrode compartment of the redox flow battery, wherein the ribs are configured to increase turbulence in electrolyte flow between the membrane separator and a negative electrode of the negative electrode compartment, and wherein the ribs extend one or more of at an angle to the vertical axis and sinuously across the membrane separator; and
infiltrating the sheet with a cross-linked polymer network by chemically activating a dilute solution of a cross-linked polymer gel stored in pores of the sheet followed by curing the chemically activated cross-linked polymer gel of the dilute solution, wherein the dilute solution includes a monomer of the cross-linked polymer gel, and wherein the monomer is one of 2-acrylamido-2-methylpropane sulfonic acid or a sodium 4-vinyl benzene sulfonate salt; and
arranging the membrane separator in a cell of the redox flow battery on a side of a positive electrode opposite of a bipolar plate, the bipolar plate formed by a second roll-to-roll calendering process with the positive electrode bonded thereto, wherein the bipolar plate is formed of a plurality of layers that are sewn together.