DCT
8:19-cv-01648
Enchanted IP LLC v. Mophie Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Enchanted IP LLC (Texas)
- Defendant: Mophie, Inc. (California)
- Plaintiff’s Counsel: Law Office of Ryan E. Hatch, PC; Chavous Intellectual Property Law LLC
- Case Identification: 8:19-cv-01648, C.D. Cal., 08/27/2019
- Venue Allegations: Venue is alleged to be proper because Defendant maintains its principal place of business in the district and has committed the alleged acts of infringement within the district.
- Core Dispute: Plaintiff alleges that Defendant’s portable power banks for mobile devices infringe a patent related to charge and discharge control circuitry for secondary batteries.
- Technical Context: The technology concerns safety and operational circuits for rechargeable batteries, designed to prevent overcharging and to enable recharging even from a fully depleted state.
- Key Procedural History: The complaint does not mention any prior litigation, inter partes review proceedings, or licensing history related to the patent-in-suit. It notes that the patent will expire no earlier than April 24, 2020.
Case Timeline
| Date | Event |
|---|---|
| 1999-12-03 | ’871 Patent Priority Date |
| 2001-02-27 | U.S. Patent No. 6,194,871 Issued |
| 2019-08-27 | Complaint for Patent Infringement Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,194,871 - "Charge and discharge control circuit and apparatus for secondary battery," Issued Feb. 27, 2001
The Invention Explained
- Problem Addressed: The patent describes two key problems with prior art secondary battery packs used in portable electronics. First, if a battery is left unused for a long time and becomes completely discharged, the control circuitry itself may become inoperative, making it impossible to recharge the battery (Compl. ¶19; ’871 Patent, col. 3:6-15). Second, when multiple battery packs are connected in parallel (e.g., to a single device), a reverse leak current from a charged pack can flow into a discharged pack, potentially tricking the discharged pack’s control circuit into an erroneous charge state (’871 Patent, col. 4:26-34).
- The Patented Solution: The invention proposes a control circuit that solves these issues by decoupling the charging decision from the battery's own voltage level. It uses a dedicated "charger detection terminal" that, when a sufficient voltage from an external charger is detected, activates a charge control switch (e.g., a P-type FET 204) to allow charging, even if the battery itself is completely dead (’871 Patent, col. 4:56-62, Fig. 1). The same circuit prevents charging if an overcharge state is detected or if the voltage at the detection terminal is below the required threshold, thereby preventing erroneous charging from a parallel-connected battery pack (’871 Patent, col. 4:51-56).
- Technical Importance: The described approach sought to simultaneously improve the safety of using multiple battery packs and enhance the reliability and lifespan of a single pack by ensuring it could be recovered from a state of complete discharge (Compl. ¶19; ’871 Patent, col. 4:39-46).
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶21).
- Independent Claim 1 recites:
- A charge and discharge control circuit for an external secondary battery;
- The circuit makes an external charge control switch nonconductive when an overcharge state is detected, interrupting the charge operation;
- The circuit comprises a "charge control element" that makes the charge control switch conductive when a "first voltage" is applied to a "detection terminal," making charging possible;
- The charge control element also makes the switch nonconductive when a "second voltage" is applied to the detection terminal, making charging impossible.
- The complaint alleges infringement of "at least one claim" of the patent, which may imply an intent to assert other claims, including dependent claims (Compl. ¶3).
III. The Accused Instrumentality
Product Identification
- The complaint identifies "Mophie's Juice Pack Reserve product" as the Accused Product (Compl. ¶20).
Functionality and Market Context
- The Accused Product is described as a compact, "external battery-based power supply which comprises charge and discharge control circuit" for smartphones and other micro-USB devices (Compl. ¶21, p. 5). Marketing materials cited in the complaint highlight features such as "Smart battery technology automatically turns power on when the reserve is connected to your device and turns off when disconnected" and "Built-in short circuit, over-charge and temperature protection" (Compl. p. 5). An infographic, sourced from a third party, illustrates five common power bank protection mechanisms, including 'Over Charge Protection' which it claims 'stops the power bank from continuing to charge a device that is outside the protection range.' (Compl. p. 6). The product is positioned as a portable solution for extending the battery life of mobile devices (Compl. p. 5).
IV. Analysis of Infringement Allegations
’871 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a charge and discharge control circuit for an external secondary battery, the charge and discharge control circuit making an external charge control switch nonconductive based on that an overcharge state of the external secondary battery is detected and interrupting a charge operation... | The Accused Product allegedly contains a charge and discharge control circuit that provides "inbuilt overcharge protection" and stops charging a connected device based on a detected overcharge state. | ¶¶21, 22, 25 | col. 8:1-14 |
| a charge control element for making the charge control switch conductive when a first voltage not less than a predetermined voltage is applied to a detection terminal for detecting whether a charger is connected thereto or not, thereby making the charge operation of the secondary battery possible, | The product allegedly includes a charge control element that "automatically turns power on" when connected to a device, which the complaint equates to a first voltage being applied to a detection terminal to enable a charge operation. | ¶23 | col. 7:15-37 |
| and for making the charge control switch nonconductive when a second voltage not more than the predetermined voltage is applied to the detection terminal, thereby making the charge operation of the secondary battery impossible. | The product's control circuit allegedly makes the charge switch nonconductive by "stopping the power bank from continuing to charge a phone" when a second, lower voltage is applied to the detection terminal, thereby making the charge operation impossible. | ¶24 | col. 5:10-20 |
- Identified Points of Contention:
- Scope Questions: A central issue may be whether the general-purpose charging port of the Accused Product, which detects the connection of a device, constitutes the "detection terminal for detecting whether a charger is connected" as recited in the claim. The patent specification appears to describe a more specific hardware terminal ("OCV" in Fig. 1) for this function.
- Technical Questions: The complaint relies on high-level marketing descriptions (e.g., "Smart battery technology") and a third-party infographic to allege infringement (Compl. pp. 5-6). A key question for the court will be whether the actual electronic circuitry of the Mophie product operates in the specific manner required by the claims. For example, what evidence demonstrates that the product's "overcharge protection" is achieved via a "charge control element" that responds to distinct "first" and "second" voltages at a specific "detection terminal," as opposed to using a different technical method to achieve a similar safety outcome?
V. Key Claim Terms for Construction
The Term: "detection terminal"
- Context and Importance: The existence and function of this "terminal" are foundational to the infringement theory. The complaint alleges that connecting the device to the power bank is equivalent to applying a voltage to this terminal (Compl. ¶23). The construction of this term will determine whether a general-purpose data/power port can meet this limitation.
- Intrinsic Evidence for a Broader Interpretation: A party arguing for a broader scope may point to the functional language of the claim itself: "a detection terminal for detecting whether a charger is connected thereto or not" (’871 Patent, col. 14:62-64), suggesting that any component that performs this detection function could qualify.
- Intrinsic Evidence for a Narrower Interpretation: The patent specification consistently depicts this element as a specific pin, labeled "OCV", which is distinct from the main power output terminals and is used to monitor for the presence of an external charger (’871 Patent, Fig. 1; col. 2:51-54). This may support an argument that the term requires a dedicated hardware structure.
The Term: "charge control element"
- Context and Importance: This term defines the core logic of the invention. Practitioners may focus on this term because the complaint maps it to the product's general "circuit for overcharge, short circuit and temperature protection" (Compl. ¶23), while the patent discloses specific circuit implementations for this element. The dispute will likely concern whether the accused general-purpose circuitry is structurally and functionally equivalent to what is claimed.
- Intrinsic Evidence for a Broader Interpretation: The claim defines the element functionally, as something "for making the charge control switch conductive" and "nonconductive" under specified conditions (’871 Patent, col. 14:57-65). This language could support an interpretation covering any circuit that achieves these functions.
- Intrinsic Evidence for a Narrower Interpretation: The detailed description discloses specific embodiments for this element, such as a circuit of bipolar transistors ("Q1", "Q2") or an inverter-driven FET ("M2") (’871 Patent, Fig. 1, Fig. 5). This could support a narrower construction limited to the disclosed structures or their equivalents.
VI. Other Allegations
- Willful Infringement: The complaint alleges that Defendant "has had knowledge of infringement of the ’871 patent, or will have knowledge of infringement of the ’871 patent upon the service of this Complaint" (Compl. ¶29). It further requests a finding that infringement after service of the complaint is "intentional and knowing," forming the basis for enhanced damages (Compl., Prayer for Relief ¶5). The complaint does not allege any facts suggesting pre-suit knowledge of the patent or infringement.
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of definitional scope: can the term "detection terminal," which the patent illustrates as a specific hardware pin ("OCV"), be construed to cover the general-purpose USB charging port of the accused power bank that detects when a device is connected?
- A key evidentiary question will be one of technical mapping: beyond general marketing statements about "overcharge protection," what factual evidence will the plaintiff provide to demonstrate that the accused product's internal circuitry performs the specific, two-part voltage-based logic (responding to a "first voltage" to enable charging and a "second voltage" to disable it) at the alleged "detection terminal" as required by Claim 1?