H01M 8/20
Indirect fuel cells
Official title: Indirect fuel cells, e.g. fuel cells with redox couple being irreversible (H01M8/18 takes precedence)
H01M8/20 (Indirect fuel cells) appears on 477 US grants and 648 published applications in this corpus.
Search patents in H01M- Granted patents
- 477
- Published applications
- 648
- Assignees
- 277
- Inventors
- 1,068
- Latest grant
- 25 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1977 | 1 | 0 |
| 1978 | 0 | 0 |
| 1979 | 0 | 0 |
| 1980 | 1 | 0 |
| 1981 | 1 | 0 |
| 1982 | 0 | 0 |
| 1983 | 2 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 1 | 0 |
| 1987 | 0 | 0 |
| 1988 | 0 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 1 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 1 | 0 |
| 1995 | 0 | 0 |
| 1996 | 1 | 0 |
| 1997 | 1 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 1 | 0 |
| 2001 | 0 | 1 |
| 2002 | 3 | 5 |
| 2003 | 1 | 5 |
| 2004 | 1 | 3 |
| 2005 | 1 | 9 |
| 2006 | 5 | 7 |
| 2007 | 2 | 3 |
| 2008 | 4 | 5 |
| 2009 | 5 | 4 |
| 2010 | 5 | 15 |
| 2011 | 3 | 25 |
| 2012 | 7 | 32 |
| 2013 | 15 | 48 |
| 2014 | 25 | 82 |
| 2015 | 39 | 92 |
| 2016 | 46 | 103 |
| 2017 | 70 | 64 |
| 2018 | 68 | 29 |
| 2019 | 53 | 25 |
| 2020 | 37 | 21 |
| 2021 | 19 | 16 |
| 2022 | 25 | 12 |
| 2023 | 13 | 15 |
| 2024 | 10 | 14 |
| 2025 | 5 | 6 |
| 2026 | 4 | 7 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Redox flow batteries and compounds for battery application25 Aug 2026US 12,719,075 B2The Trustees of Columbia University in the City of New York
- System and process for anthraquinone functionalization7 Apr 2026US 12,595,574 B2President and Fellows of Harvard College
- Cell stack and redox flow battery31 Mar 2026US 12,592,406 B2Sumitomo Electric Industries, Ltd.
- Sealed aqueous flow battery systems with in-tank electrolyte rebalancing6 Jan 2026US 12,519,121 B2Case Western Reserve University
- In-situ electrolyte preparation in flow battery21 Oct 2025US 12,451,528 B2Rtx Corporation
- Power generating apparatus, system and method for utilising of the chemical energy of a flowing ionic medium, in particular waste water27 Aug 2026US 2026/0253932 A1
- Composite Proton Exchange Membrane Composition and Method of Preparation16 Jul 2026US 2026/0204607 A1Saudi Arabian Oil Company
- Method and System for Rebalancing Electrolytes in a Redox Flow Battery System18 Jun 2026US 2026/0171454 A1Ess Tech, Inc.
- Redox flow battery18 Jun 2026US 2026/0171468 A1Green Energy Storage S.R.L.
- Vanadium-chromium electrolyte, method for preparing the same, and redox flow battery composed thereof26 Mar 2026US 2026/0088317 A1Dalian Rongke Power Group Co., Ltd
Most cited
By later US patents
- High energy density redox flow device172US 8,722,226 B224M Technologies, Inc. · 2014
- High energy density redox flow device134US 9,153,833 B224M Technologies, Inc. · 2015
- Semi-solid electrodes having high rate capability132US 8,993,159 B224M Technologies, Inc. · 2015
- High energy density redox flow device122US 8,722,227 B224-M Technologies, Inc. · 2014
- Fuel system using redox flow battery108US 8,778,552 B224M Technologies, Inc. · 2014