Ascend Elements Inc v. Duesenfeld GmbH

1. Case Identification

• Case #: PGR2025-00037
• Patent #: 12,119,463
• Filed: March 7, 2025
• Petitioner(s): Ascend Elements, Inc.
• Patent Owner(s): Duesenfeld GmbH
• Challenged Claims: 1-14

2. Patent Overview

• Title: Method for Treating Used Lithium Batteries
• Brief Description: The ’463 patent discloses a method for recycling used lithium-ion batteries. The process involves comminuting (shredding) the batteries and subsequently inactivating the resulting material through a drying process conducted at relatively low temperatures and reduced pressures to remove organic carbonate electrolyte.

3. Grounds for Unpatentability

Ground 1: Obviousness over Tomioka - Claims 1-3, 8, and 10-12 are obvious over Tomioka

• Prior Art Relied Upon: Tomioka (Japanese Patent Application Publication No. JPH10255861).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Tomioka, which relates to recycling used lithium-ion batteries, teaches all limitations of independent claim 1. Tomioka allegedly discloses a method of dismantling batteries (comminuting) and then drying the material in a container under vacuum at a pressure of approximately 133 hPa and a temperature below 40°C. Petitioner contended this process, which achieves a 99% solvent recovery rate, inherently performs the claimed "inactivating" by removing the electrolyte. Petitioner further asserted that Tomioka discloses features of dependent claims, including a condenser to capture vaporized gases (claim 3), performing both comminution and drying within the same container for safety and efficiency (claim 8), and processing material to a sieve size of 10 mm or less (claim 10).

Ground 2: Obviousness over Hanisch and Hayashi - Claims 1-3, 5, 9-12 are obvious over Hanisch in view of Hayashi

• Prior Art Relied Upon: Hanisch (Application # 2014/0290438) and Hayashi (Patent 9,843,077).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Hanisch, a publication from the inventor of the ’463 patent, discloses the core claimed method: crushing galvanic cells and drying the fragments in a "pre-dryer" at temperatures "below 80°C" and "in a vacuum." This process forms "dry cell fragments" by removing electrolyte vapors, which are then condensed and retrieved.
  • Motivation to Combine: While Hanisch teaches drying under a general vacuum, Hayashi provides specific, well-understood parameters for doing so efficiently. Petitioner argued a person of ordinary skill in the art (POSITA) would combine Hayashi’s explicit teachings on the relationship between reduced pressure (<100 hPa) and the lower boiling points of organic carbonates with Hanisch’s process. This combination would optimize Hanisch’s method to ensure efficient vaporization at the specified low temperatures.
  • Expectation of Success: A POSITA would have a high expectation of success, as this combination involves applying known thermodynamic principles from Hayashi to improve the efficiency and control of the known battery recycling process of Hanisch.

Ground 3: Obviousness over Tomioka and Yosuke - Claim 4 is obvious over Tomioka in view of Yosuke

• Prior Art Relied Upon: Tomioka (Japanese Patent Application Publication No. JPH10255861) and Yosuke (Japanese Patent Application Publication No. JP2016080284A).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that claim 4 adds continuous monitoring of a process parameter (e.g., pressure) to terminate the drying process once a threshold is met. While Tomioka teaches the basic drying system, Yosuke specifically discloses a method to "accurately determine the completion of vacuum drying" for battery electrodes. Yosuke teaches using a "pressure measurement means" to monitor the pressure inside a drying oven and a controller to determine when the pressure drops below a target value, indicating completion.
  • Motivation to Combine: A POSITA would be motivated to incorporate Yosuke’s straightforward process control technique into Tomioka’s drying system to enhance its performance. Adding a pressure sensor and controller to automate the endpoint of the drying cycle is an obvious way to improve process consistency, prevent under- or over-drying, and increase efficiency.
  • Expectation of Success: Success would be predictable, as it involves integrating a standard monitoring and control system into a known drying process to achieve more reliable and predictable results.

• Additional Grounds: Petitioner asserted additional obviousness challenges based on combinations of Tomioka or Hanisch with LithoRec (a publication teaching an airlock for feeding material into a dryer) and Perry (a chemical engineering handbook teaching the use of agitated dryers). Petitioner also asserted that all challenged claims are invalid for indefiniteness under 35 U.S.C. §112.

4. Key Claim Construction Positions

• inactivat[e]/[ed]/[ing]/[tion]: Petitioner argued this term is fatally indefinite. The specification and claims allegedly fail to provide a POSITA with reasonable certainty as to when comminuted material is considered "inactivated," as distinct from merely being "dried." Petitioner highlighted that Patent Owner has taken inconsistent positions on the term's meaning in related proceedings. For the purpose of its prior art arguments under 35 U.S.C. §103, Petitioner adopted Patent Owner's proposed construction from a related IPR, "the endpoint of drying," while maintaining its indefiniteness challenge.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial would be inappropriate.
• Under 35 U.S.C. §325(d), Petitioner contended that key prior art references (Tomioka and Yosuke) were never before the examiner. It also argued that other references presented in the petition (Hanisch, Hayashi, LithoRec, Perry), while some were previously of record, were not substantively analyzed or applied in the context of the new invalidity theories presented.
• Regarding the Fintiv factors under 35 U.S.C. §324(a), Petitioner noted that the parallel district court proceeding has been stayed pending a related IPR, no trial date is set, and minimal investment has occurred. Petitioner also stipulated that it would not pursue the same invalidity grounds in the district court if the post-grant review is instituted.

6. Relief Requested

• Petitioner requests institution of a post-grant review and cancellation of claims 1-14 of the ’463 patent as unpatentable.