DCT
6:21-cv-00347
Maxell Ltd v. Amperex Technology Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Maxell Holdings, Ltd. (Japan)
- Defendant: Amperex Technology Limited (China)
- Plaintiff’s Counsel: Vinson & Elkins LLP
- Case Identification: 6:21-cv-00347, W.D. Tex., 04/08/2021
- Venue Allegations: Plaintiff alleges that because Defendant is not a resident of the United States, venue is proper in any judicial district pursuant to 28 U.S.C. § 1391(c)(3).
- Core Dispute: Plaintiff alleges that Defendant’s lithium-ion batteries, used in a wide range of consumer electronics, infringe four patents related to battery component chemistry, structure, and safety features.
- Technical Context: The technology at issue is lithium-ion battery (LIB) design and chemistry, a foundational technology for the multibillion-dollar global market for portable electronics such as smartphones, laptops, and drones.
- Key Procedural History: The complaint notes a history between the parties, including discussions for a potential commercial collaboration that began around July 2012 but were abandoned in 2013. Plaintiff also alleges it sent letters to Defendant regarding its patent portfolio on March 27, 2020, and March 26, 2021, which may be relevant to allegations of willful infringement.
Case Timeline
| Date | Event |
|---|---|
| 2006-03-20 | Earliest Priority Date for '035 Patent |
| 2006-10-26 | Earliest Priority Date for '446 and '019 Patents |
| 2007-10-03 | Earliest Priority Date for '251 Patent |
| 2012-07-01 | Parties allegedly enter non-disclosure agreements |
| 2013-01-01 | Parties allegedly abandon collaboration efforts |
| 2014-04-08 | '446 Patent Issued |
| 2015-07-07 | '035 Patent Issued |
| 2015-10-20 | '251 Patent Issued |
| 2016-05-24 | '019 Patent Issued |
| 2020-03-27 | Plaintiff sends letter to Defendant identifying patents |
| 2021-03-26 | Plaintiff sends second letter to Defendant |
| 2021-04-08 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,691,446 - "Nonaqueous Secondary Battery And Method Of Using The Same," Issued April 8, 2014
The Invention Explained
- Problem Addressed: The patent describes a problem with conventional lithium-ion batteries, where attempts to increase energy density by charging to higher voltages (above 4.2V) cause the crystalline structure of the positive electrode material (e.g., LiCoO₂) to decay. This decay shortens the battery's cycle life and degrades its thermal stability, posing safety risks (Compl. ¶55; ’446 Patent, col. 1:49-2:46).
- The Patented Solution: The invention claims to solve this by modifying both the positive electrode and the electrolyte. The positive electrode's active material is a mixture of at least two different types of lithium-containing transition metal oxide particles (with different sizes and chemical compositions) to improve stability, and the electrode mixture layer is made highly dense (at least 3.5 g/cm³). The nonaqueous electrolyte contains a compound with at least two nitrile groups, which forms a protective film on the positive electrode surface to suppress gas generation and battery swelling during storage at high temperatures (’446 Patent, Abstract; col. 4:27-51).
- Technical Importance: This combination of material and chemical improvements was intended to allow for the design of batteries with higher capacity and the ability to operate safely at higher voltages, meeting the demands of increasingly power-hungry consumer electronics (Compl. ¶5).
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶72-73).
- Essential elements of claim 1 include:
- A nonaqueous secondary battery with a positive electrode, a negative electrode, and a nonaqueous electrolyte.
- The positive electrode's active material contains at least two lithium-containing transition metal oxides with different average particle sizes and different elemental compositions.
- The lithium-containing transition metal oxide with the smallest average particle size has a specific chemical formula (Formula 1).
- The positive electrode mixture layer has a density of at least 3.5 g/cm³.
- The electrolyte contains a compound with at least two nitrile groups.
U.S. Patent No. 9,350,019 - "Nonaqueous Secondary Battery And Method Of Using The Same," Issued May 24, 2016
The Invention Explained
- Problem Addressed: As a divisional of the application that led to the ’446 Patent, this patent addresses the same fundamental challenge: improving the capacity and stability of lithium-ion batteries, particularly when charged to higher voltages (Compl. ¶57).
- The Patented Solution: The solution is structurally similar to that of the ’446 Patent, involving a positive electrode with a mixture of different oxide particles and an electrolyte with a nitrile-group compound. However, the claims of the ’019 Patent add a more specific limitation: the amount of magnesium (Mg) in the chemical formula for the smallest oxide particles must be within a specific range (0.15% to less than 2% by mole). This suggests a refinement to optimize the stabilizing effect of the added elements (’019 Patent, Claim 1).
- Technical Importance: By claiming a specific concentration range for a key stabilizing element (Mg), the invention points to a potentially optimized chemical formulation for achieving high performance and reliability in high-voltage batteries (Compl. ¶5).
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶94-95).
- Essential elements of claim 1 are nearly identical to claim 1 of the ’446 patent, with the addition of the following key limitation:
- A content of Mg in the specified formula for the smallest particle size oxide is from 0.15% by mole to less than 2% by mole based on the amount of the metal element M¹.
U.S. Patent No. 9,077,035 - "Nonaqueous Secondary Battery And Method Of Using The Same," Issued July 7, 2015
- Patent Identification: U.S. Patent No. 9,077,035, "Nonaqueous Secondary Battery And Method Of Using The Same," Issued July 7, 2015 (Compl. ¶58).
- Technology Synopsis: This patent is directed to improving battery performance using a positive electrode that contains a blend of at least two lithium-containing transition metal oxides with different average particle sizes and specific weight percentage ranges. The invention also requires the electrolyte to contain a fluorine-containing organic solvent (Compl. ¶59, ¶117). An inter partes review of this patent resulted in the cancellation of all claims (IPR2021-01441).
- Asserted Claims: Independent claim 1 is asserted (Compl. ¶116-117).
- Accused Features: The accused LIBs are alleged to contain positive electrodes with the claimed blend of different-sized oxide particles and an electrolyte with a fluorine-containing organic solvent (Compl. ¶119-121).
U.S. Patent No. 9,166,251 - "Battery Separator And Nonaqueous Electrolyte Battery," Issued October 20, 2015
- Patent Identification: U.S. Patent No. 9,166,251, "Battery Separator And Nonaqueous Electrolyte Battery," Issued October 20, 2015 (Compl. ¶60).
- Technology Synopsis: This patent focuses on battery safety through an improved separator architecture. The invention claims a multilayer battery separator comprising a "shutdown layer" made of a heat-shrinkable film and a "heat-resistant layer" made of fine particles and a binder. The claims specify distinct parameters for layer thicknesses, thickness ratios, and particle size distributions within the heat-resistant layer to ensure safe operation at high temperatures (Compl. ¶61, ¶140).
- Asserted Claims: Independent claims 1 and 10 are asserted (Compl. ¶139).
- Accused Features: ATL's Cell No. 575577N is specifically accused of incorporating a separator that meets the structural, material, and dimensional limitations of the asserted claims (Compl. ¶142-143).
III. The Accused Instrumentality
Product Identification
- The accused products are rechargeable lithium-ion battery (LIB) cells, packs, and systems designed, manufactured, and sold by Defendant ATL (Compl. ¶16, ¶62). The complaint identifies specific exemplary models, including ATL Cell Nos. 465867, 575577N, 785075, 633360, and 2798B7 (Compl. ¶20).
Functionality and Market Context
- The complaint alleges these LIBs are incorporated into a wide variety of globally distributed consumer electronics, including the Google Pixel 3a smartphone, Dell Alienware Type 44T2R notebook battery, DJI Mavic and Spark drones, and the Huawei MediaPad M5 Lite tablet (Compl. ¶20, ¶62). The complaint includes a photograph of the accused ATL LIB Cell No. 465867, allegedly removed from a Google Pixel 3a smartphone, showing ATL's branding and model number (Compl. p. 7). ATL is positioned in the complaint as a "world's leading producer and innovator of lithium-ion batteries" that works closely with major OEMs (Compl. ¶15, ¶17). Further photographs identify other accused ATL cells within products such as a Dell notebook battery and a DJI drone battery (Compl. p. 9, 12).
IV. Analysis of Infringement Allegations
U.S. Patent No. 8,691,446 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A nonaqueous secondary battery comprising: a positive electrode having a positive electrode mixture layer, a negative electrode, and a nonaqueous electrolyte | The accused LIBs are alleged to be nonaqueous secondary batteries with these fundamental components (Compl. ¶75, ¶77, ¶79, ¶81, ¶83). | ¶75 | col. 2:52-56 |
| wherein the positive electrode contains, as an active material, at least two lithium-containing transition metal oxides having different average particle sizes | The complaint alleges, based on preliminary analysis, that the positive electrode active material in the accused LIBs contains more than one type of lithium-containing transition metal oxide with different particle sizes (Compl. ¶75). | ¶75 | col. 8:55-59 |
| wherein said at least two lithium-containing transition metal oxides ... have different compositions of elements between them | The complaint alleges that the different-sized oxides also have different elemental compositions (Compl. ¶75). | ¶75 | col. 10:9-13 |
| said lithium-containing transition metal oxide having the smallest average particle size is a lithium-containing transition metal oxide represented by the formula (1) | The complaint alleges that the smallest oxide particles in the accused LIBs satisfy the specific chemical requirements of Formula 1 (Compl. ¶75). | ¶75 | col. 10:60-11:13 |
| the positive electrode mixture layer has a density of at least 3.5 g/cm³ | The complaint alleges upon information and belief that the positive electrode mixture layer in the accused LIBs has the claimed minimum density (Compl. ¶75). | ¶75 | col. 8:50-54 |
| the nonaqueous electrolyte contains a compound having at least two nitrile groups in the molecule | The complaint alleges upon information and belief that the electrolyte in the accused LIBs contains a compound with at least two nitrile groups (Compl. ¶75). | ¶75 | col. 4:27-41 |
U.S. Patent No. 9,350,019 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| ...at least two lithium-containing transition metal oxides having different average particle sizes | The complaint alleges that the accused LIBs' positive electrodes contain at least two types of lithium-containing transition metal oxides with different particle sizes and compositions (Compl. ¶97). | ¶97 | col. 8:55-59 |
| a content of Mg in the formula (1) is from 0.15% by mole to less than 2% by mole based on an amount of the metal element M¹ | The complaint alleges upon information and belief that the magnesium content in the smallest oxide particles in the accused LIBs falls within this specific claimed range (Compl. ¶97). | ¶97 | col. 11:14-19 |
| the positive electrode mixture layer has a density of at least 3.5 g/cm³; and the nonaqueous electrolyte contains a compound having at least two nitrile groups in the molecule | The complaint alleges the accused LIBs meet these limitations regarding electrode density and electrolyte composition (Compl. ¶97). | ¶97 | col. 8:50-54; col. 4:27-41 |
Identified Points of Contention
- Evidentiary Questions: The complaint's infringement allegations for the '446 and '019 patents rely heavily on "information and belief" and "preliminary analysis." A primary point of contention will be evidentiary. What technical evidence, such as from reverse engineering or chemical analysis, will Plaintiff produce to demonstrate that the accused ATL batteries actually meet every quantitative limitation of the claims? This includes proving (1) the presence of at least two distinct oxide populations with different sizes and compositions, (2) the specific elemental ranges required by the formulas, particularly the narrow magnesium content window in the '019 Patent, (3) the positive electrode density of at least 3.5 g/cm³, and (4) the presence of a dinitrile compound in the electrolyte.
V. Key Claim Terms for Construction
- The Term: "different compositions of elements between them" (’446 Patent, Claim 1)
- Context and Importance: This term is critical because it requires that the multiple oxide populations in the positive electrode differ not only in particle size but also in their fundamental chemical makeup. The case may turn on how significant this compositional difference must be to meet the claim limitation. Practitioners may focus on whether minor, process-related variations suffice or if a material, intentional difference in formulation is required.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The plain language of the claim does not quantify the required "difference," which may support an argument that any scientifically detectable variation in elemental ratios between the oxide populations meets the limitation.
- Evidence for a Narrower Interpretation: The patent specification provides examples where the different oxide populations have distinctly different formulas (e.g., one is a Li-Co-Mg-Ti-Al oxide while another is a Li-Co-Ni-Mn-Mg-Ti-Al oxide) (Compl. Ex. 1, '446 Patent, col. 15:15-19). A defendant may argue that the term should be construed to require a similarly material difference in the types or ratios of constituent elements, not merely incidental manufacturing variances.
VI. Other Allegations
Indirect Infringement
- The complaint alleges both induced and contributory infringement. Inducement is based on allegations that ATL had knowledge of the patents from at least March 27, 2020, and took affirmative steps to cause infringement by its customers and distributors, such as by creating distribution channels, providing instruction manuals, and ensuring products comply with U.S. standards (Compl. ¶85, ¶107). Contributory infringement is based on the allegation that ATL's LIBs are material components specifically designed for infringing use with no substantial non-infringing uses (Compl. ¶86, ¶108).
Willful Infringement
- The complaint alleges that ATL's infringement has been willful and deliberate since it gained knowledge of the asserted patents, at least as early as its receipt of a letter from Maxell on March 27, 2020 (Compl. ¶87, ¶109).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of evidentiary demonstration: Can Plaintiff produce technical evidence from testing and analysis of the accused batteries that is sufficiently robust to prove that their internal materials and structures meet the specific, quantitative limitations of the asserted claims, including the particle size distributions, elemental compositions, electrode densities, and electrolyte additives?
- A key question for damages will be one of scienter and intent: Assuming infringement is established, did Defendant's alleged conduct after receiving notice letters from Plaintiff in March 2020 and March 2021 rise to the level of willfulness required to justify an award of enhanced damages?