公开(公告)号：US20230061531A1

公开(公告)日：2023-03-02

申请号：US17816256

申请日：2022-07-29

Applicant: ESS TECH, INC.

Inventor： Yang Song ,  Craig Evans

IPC: H01M8/18 ,  H01M8/04082

Abstract: Systems and methods are provided for electrolyte and current circulation in a redox flow battery system. In one example, the redox flow battery system may include a plurality of redox flow battery cells electrically coupled in series. In this way, a potential difference across the plurality of redox flow battery cells may be ramped up, such that relatively high voltage external loads may be powered by the redox flow battery system. In some examples, each of the plurality of redox flow battery cells may be fluidically isolated from one another. As such, in one example, the redox flow battery system may further include a plurality of electrolyte storage tanks respectively fluidically coupled to the plurality of redox flow battery cells. Such fluidic isolation of each of the plurality of redox flow battery cells may eliminate stack-to-stack shunting in the redox flow battery system, as well as improve a modularity thereof.

公开(公告)号：US20230028170A1

公开(公告)日：2023-01-26

申请号：US17937391

申请日：2022-09-30

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：US20230016796A1

公开(公告)日：2023-01-19

申请号：US17932245

申请日：2022-09-14

Applicant: ESS TECH, INC.

Inventor： Craig Evans ,  Sean Kissick ,  Yang Song

IPC: H01M8/18 ,  H01M8/0297

Abstract: Systems and methods are provided for a rebalancing cell for a redox flow battery. In one example, a rebalancing cell for a redox flow battery includes a cell enclosure and a stack of electrode assemblies enclosed by the cell enclosure, where each electrode assembly of the stack of electrode assemblies including a positive electrode interfacing with a flow field plate. A face of the flow field plate interfacing with the positive electrode has a plurality of passages including tapered inlets and outlets and partial channels configured to remove gas from electrolyte flowing therethrough.

公开(公告)号：US11545688B2

公开(公告)日：2023-01-03

申请号：US17234509

申请日：2021-04-19

Applicant: ESS TECH, INC.

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

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

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：US20220399561A1

公开(公告)日：2022-12-15

申请号：US17821759

申请日：2022-08-23

Applicant: ESS TECH, INC.

Inventor： Sean Casey ,  Craig Evans

IPC: H01M8/248 ,  H01M8/18

Abstract: Methods and systems are provided for a redox flow battery system. In one example, the redox flow battery system has a first redox flow battery and a second redox flow battery, stacked above and in contact with the first redox flow battery along a vertical axis of the redox flow battery system. The second redox flow battery may be coupled to the first redox flow battery via nesting detents. Furthermore, operation of the first redox flow battery and the second redox flow battery may be adjustable according to a power demand.

公开(公告)号：US20220231309A1

公开(公告)日：2022-07-21

申请号：US17653620

申请日：2022-03-04

Applicant: ESS TECH, INC.

Inventor： Craig E. Evans ,  Sean Casey ,  Yang Song

IPC: H01M8/0258 ,  H01M8/18 ,  H01M8/0239 ,  H01M4/88 ,  H01M8/20 ,  H01M8/0245

Abstract: A redox flow battery may include: a membrane interposed between a first electrode positioned at a first side of the membrane and a second electrode positioned at a second side of the membrane opposite to the first side; a first flow field plate comprising a plurality of positive flow field ribs, each of the plurality of positive flow field ribs contacting the first electrode at first supporting regions on the first side; and the second electrode, including an electrode spacer positioned between the membrane and a second flow field plate, the electrode spacer comprising a plurality of main ribs, each of the plurality of main ribs contacting the second flow field plate at second supporting regions on the second side, each of the second supporting regions aligned opposite to one of the plurality of first supporting regions. As such, a current density distribution at a plating surface may be reduced.

公开(公告)号：US11374236B2

公开(公告)日：2022-06-28

申请号：US15601560

申请日：2017-05-22

Applicant: ESS TECH, INC.

Inventor： Craig E. Evans ,  Sean Casey ,  Yang Song

IPC: H01M8/0258 ,  H01M8/18 ,  H01M8/0239 ,  H01M4/88 ,  H01M8/20 ,  H01M8/0245

Abstract: A redox flow battery may include: a membrane interposed between a first electrode positioned at a first side of the membrane and a second electrode positioned at a second side of the membrane opposite to the first side; a first flow field plate comprising a plurality of positive flow field ribs, each of the plurality of positive flow field ribs contacting the first electrode at first supporting regions on the first side; and the second electrode, including an electrode spacer positioned between the membrane and a second flow field plate, the electrode spacer comprising a plurality of main ribs, each of the plurality of main ribs contacting the second flow field plate at second supporting regions on the second side, each of the second supporting regions aligned opposite to one of the plurality of first supporting regions. As such, a current density distribution at a plating surface may be reduced.

公开(公告)号：US20220149417A1

公开(公告)日：2022-05-12

申请号：US17645293

申请日：2021-12-20

Applicant: ESS Tech, Inc.

Inventor： Yang Song ,  Craig E. Evans

IPC: H01M8/18 ,  H01M8/04186 ,  G06V40/13 ,  G06V40/12 ,  H01M8/04537 ,  H01M8/04858 ,  H01M8/06

Abstract: A method of cleansing a redox flow battery system may include operating the redox flow battery system in a charge, discharge, or idle mode, and responsive to a redox flow battery capacity being less than a threshold battery capacity, mixing the positive electrolyte with the negative electrolyte. In this way, battery capacity degradation following cyclic charging and discharging of the redox flow battery system can be substantially reduced.

公开(公告)号：US20220123344A1

公开(公告)日：2022-04-21

申请号：US17456948

申请日：2021-11-30

Applicant: ESS Tech, Inc.

Inventor： Yang Song ,  Kenneth Kiyoshi Fisher ,  Timothy McDonald

IPC: H01M8/18 ,  H01M8/2455 ,  H01M8/0202 ,  H01M8/04007 ,  H01M8/04082 ,  H01M8/04089 ,  H01M8/0289 ,  H01M8/2484

Abstract: A multi-chambered electrolyte storage tank for a redox flow battery system, may include first and second electrolyte chambers, and a bulkhead, wherein the first and second electrolyte chambers are fluidly coupled to first and second sides of a redox flow battery cell, respectively, the first and second electrolyte chambers include first and second liquid electrolyte volumes, respectively, and the first and second liquid electrolyte volumes are separated by the bulkhead positioned therebetween. In this way, manufacturing and operational complexity of a redox flow battery system can be reduced.

公开(公告)号：US20210359328A1

公开(公告)日：2021-11-18

申请号：US17308862

申请日：2021-05-05

Applicant: ESS Tech, Inc.

Inventor： Craig E. Evans ,  Sean Casey ,  Thiago Groberg ,  Yang Song

IPC: H01M8/18 ,  H01M8/2455

Abstract: A redox flow battery and battery system are provided. In one example, the redox flow battery includes a cell stack assembly interposed by two endplates and comprising a plurality of mated membrane frame plates and bipolar frame plates forming, at a mated interface, a plurality of negative and positive flow channels configured to distribute negative and positive electrolyte into a plurality of bipolar plates. In the battery a membrane is coupled to each of the plurality of membrane frame plates and positioned sequentially between two of the bipolar plates included in the plurality of bipolar plates.