公开(公告)号：US20210313811A1

公开(公告)日：2021-10-07

申请号：US17238099

申请日：2021-04-22

Applicant: ESS TECH, INC.

Inventor： Aaron Vanderzanden ,  Steve Ernst

IPC: H02J7/00 ,  H01M8/18

Abstract: Systems and methods for operating an electric energy storage system are described. The systems and methods include ways of coupling electric energy storage cell stacks to an electric conductor or bus. The coupling is performed to reduce current flow through contactors and to increase a life span of the contactors.

公开(公告)号：US20210313589A1

公开(公告)日：2021-10-07

申请号：US17235810

申请日：2021-04-20

Applicant: ESS TECH, INC.

Inventor： Craig E. Evans ,  Yang Song ,  Jeffrey Chen

IPC: H01M4/88 ,  H01M8/0239 ,  H01M8/0245 ,  H01M8/18 ,  H01M8/20

Abstract: An electrode for use in an all-iron redox flow battery is provided. In one example, the electrode may include a plastic mesh; and a coating on the plastic mesh. The coating may be a hydrophilic coating or a conductive coating and the electrode may have an electrode reaction potential is less than 0.8V. Further, a method of manufacturing a coated plastic mesh electrode for use in an all-iron redox flow battery is provided. In one example method, the steps include fabricating a plastic mesh, treating the plastic mesh by applying a solvent treatment or a plasma treatment or a mechanical abrasion treatment; coating the plastic mesh with a material selected from: carbon inks, metal oxides, and hydrophilic polymers.

公开(公告)号：US20210234184A1

公开(公告)日：2021-07-29

申请号：US17229719

申请日：2021-04-13

Applicant: ESS Tech, Inc.

Inventor： Yang Song

IPC: H01M8/18 ,  H01M4/58 ,  H01M4/36 ,  H01M8/02

Abstract: Methods and systems are provided for a redox flow battery system. In one example, the redox flow battery is adapted with an additive included in a battery electrolyte and an anion exchange membrane separator dividing positive electrolyte from negative electrolyte. An overall system cost of the battery system may be reduced while a storage capacity, energy density and performance may be increased.

公开(公告)号：US20210210775A1

公开(公告)日：2021-07-08

申请号：US17153766

申请日：2021-01-20

Applicant: ESS Tech, Inc.

Inventor： Isaac Walker-Stern ,  Aaron Vanderzanden

IPC: H01M8/04186 ,  H01M8/18 ,  H01M8/04276 ,  H01M8/04955 ,  H01M8/04537

Abstract: Systems and methods for operating an electric energy storage device are described. The systems and methods may reduce a voltage potential between a ground reference and terminals of an electric energy storage device. By lowering the voltage potential, a possibility of unintentionally discharging the electrical energy storage device to ground may be reduced.

公开(公告)号：US20210143463A1

公开(公告)日：2021-05-13

申请号：US17151611

申请日：2021-01-18

Applicant: ESS TECH, INC.

Inventor： Yang Song ,  Craig E. Evans

IPC: H01M8/18 ,  H01M8/20 ,  H01M8/00 ,  H01M8/06

Abstract: A method of rebalancing electrolytes in a redox flow battery system comprises directing hydrogen gas generated on the negative side of the redox flow battery system to a catalyst surface, and fluidly contacting the hydrogen gas with an electrolyte comprising a metal ion at the catalyst surface, wherein the metal ion is chemically reduced by the hydrogen gas at the catalyst surface, and a state of charge of the electrolyte and pH of the electrolyte remain substantially balanced.

公开(公告)号：US20200161685A1

公开(公告)日：2020-05-21

申请号：US16684429

申请日：2019-11-14

Applicant: ESS TECH, INC.

Inventor： Yang Song ,  Timothy J. McDonald ,  Alexandria Behr

IPC: H01M8/06 ,  H01M8/18 ,  H01M8/04186 ,  H01M8/04746 ,  H01M8/0444

Abstract: Methods and systems are provided for a rebalancing reactor of a flow battery system. In one example, a pH of a battery electrolyte may be maintained by the rebalancing reactor by applying a negative potential to a catalyst bed of the rebalancing reactor. A performance of the rebalancing reactor may further be maintained by treating the catalyst bed with deionized water.

公开(公告)号：US10586996B2

公开(公告)日：2020-03-10

申请号：US15436593

申请日：2017-02-17

Applicant: ESS TECH, INC.

Inventor： Craig E. Evans ,  Yang Song

IPC: H01M8/18 ,  H01M8/04186 ,  H01M8/04791 ,  H01M8/04701 ,  H01M8/20

Abstract: A method of operating an iron redox flow battery system may comprise fluidly coupling a plating electrode of an iron redox flow battery cell to a plating electrolyte; fluidly coupling a redox electrode of the iron redox flow battery cell to a redox electrolyte; fluidly coupling a ductile plating additive to one or both of the plating electrolyte and the redox electrolyte; and increasing an amount of the ductile plating additive to the plating electrolyte in response to an increase in the plating stress at the plating electrode. In this way, ductile Fe can be plated on the negative electrode, and the performance, reliability and efficiency of the iron redox flow battery can be maintained. In addition, iron can be more rapidly produced and plated at the plating electrode, thereby achieving a higher charging rate for all iron flow batteries.

公开(公告)号：US20200052318A1

公开(公告)日：2020-02-13

申请号：US16536216

申请日：2019-08-08

Applicant: ESS TECH, INC.

Inventor： Craig E. Evans

IPC: H01M8/18 ,  H01M8/0202 ,  H01M4/66 ,  H01M2/16

Abstract: Methods and systems are provided for manufacturing a bipolar plate for a redox flow battery. In one example, the bipolar plate is fabricated by a roll-to-roll process. The bipolar plate includes a non-conductive substrate that is coupled to a negative electrode on a first surface and coupled to a positive electrode on a second surface, the first surface opposite of the second surface.

公开(公告)号：US20180316033A1

公开(公告)日：2018-11-01

申请号：US15965728

申请日：2018-04-27

Applicant: ESS TECH, INC.

Inventor： Craig E. Evans

IPC: H01M8/0662 ,  H01M8/18 ,  H01M8/2455 ,  H01M8/04276

Abstract: A rebalancing reactor for a redox flow battery system may include a first side through which hydrogen gas is flowed, a second side through which electrolyte from the redox flow battery system is flowed, and a porous layer separating and fluidly coupled to the first side and the second side, wherein, the hydrogen gas and the electrolyte are fluidly contacted at a surface of the porous layer, and a pressure drop across the second side is less than a pressure drop across the porous layer. In this way, rebalancing of electrolyte charges in a redox flow battery system may be performed with increased efficiency and cost effectiveness as compared to conventional rebalancing reactors.

公开(公告)号：US20180233834A1

公开(公告)日：2018-08-16

申请号：US15891277

申请日：2018-02-07

Applicant: ESS TECH, INC

Inventor： Craig E. Evans ,  Sean Casey

IPC: H01R4/48 ,  H01M8/2485 ,  H01M8/248 ,  H01M8/0258 ,  H01M10/04 ,  H01M2/20

Abstract: A leaf spring compression system comprising a mechanical assembly for securing a plurality of leaf springs on a battery cell stack of a flow battery system is disclosed. The cell stack may, comprise: a plurality of cells stacked together to form a flow battery; and a compression system comprising at least two tie rods extending through the plurality of cells clamping a spring acting at opposite ends to compress the cells together, the spring contacting at least two fulcrum elements positioned between the tie rods. In this way, the compression system may exert uniform loading on the battery cell stack, while minimizing deflection of pressure plates attached to the cell stack.