On April 1, 2025, Shenzhen Fbtech Electronics Ltd. petitioned for inter partes review of U.S. Patents 9,954,207 (“the ’207 patent”) and 9,412,994 (“the ’994 patent”). Shenzhen Fbtech Elecs Ltd. v. LithiumHub, LLC, IPR2025-00822, Paper 1 (PTAB April 1, 2025); Shenzhen Fbtech Elecs Ltd. v. LithiumHub, LLC, IPR2025-00825, Paper 1 (PTAB April 1, 2025).
The patent owner, LithiumHub, LLC, asserted these two patents in at least six district court cases and one ITC case. See, e.g., LithiumHub, LLC v. Shenzhen Fbtech Elecs. Ltd., Case No. 5:2024-cv-00133 (E.D. Tex.); LithiumHub, LLC v. Shenzhen LiTime Tech. Co., Ltd., Case No. 5:2024-cv-00134 (E.D. Tex.); LithiumHub, LLC v. Relion Battery (Shenzhen) Tech. Co., Case No. 5:2024-cv-00135 (E.D. Tex.); LithiumHub, LLC v. Renogy New Energy Co., Ltd., Case No. 5:2024-cv-00136 (E.D. Tex.); LithiumHub, LLC v. Shenzhen Yichen S-Power Tech Co., Ltd., Case No. 5:2024-cv-00137 (E.D. Tex.); LithiumHub, LLC v. Bass Pro Outdoor World LLC, Case No. 7:2024-cv-00220 (W.D. Tex.); Certain Rechargeable Batteries and Components Thereof, Case No. 337-TA-1421 (ITC).
According to one of the complaints, the inventor of the ’207 patent and the ’994 patent is Martin Koebler, who “has worked in the rechargeable battery industry for many years” and researched, designed, and developed the technology covered by the two patents while self-employed at a company he founded. LithiumHub, LLC v. Shenzhen Fbtech Elecs. Ltd., Case No. 5:2024-cv-00133, Dkt. No. 1, ¶¶ 16-17 (E.D. Tex. Sept. 13, 2024).
The ’207 patent, titled “Lithium Battery with Solid State Switch,” and its parent the ’994 patent, titled “Lithium Starter Battery and Solid State Switch Therefor,” are purportedly directed to a lithium-based cell for starting an internal combustion engine, and includes “a solid state switching configuration for high powered battery systems for protecting against over-charging, over-discharging and short circuiting of batteries, especially starter batteries for internal combustion engines.” The ’207 patent, Abstract.
According to the ’207 patent, internal combustion engines conventionally use lead-acid starter batteries that come with a number of disadvantages such as (1) being heavy and bulky, (2) having a short life, low efficiency, high resistance in cold weather, and (3) using circuits that induce heat and electric losses, take up space, and are error-prone. The ’207 patent, 1:30-64.
The purported invention of the ’207 patent uses lithium cells. According to the ’207 patent, compared to lead-acid cells, lithium cells are smaller and lighter, have a lower self-discharge rate and the ability to operate at very high temperatures (up to 70° C) and very low temperatures (down to -30° C), and are more energy efficient. The ’207 patent, 8:3-21.
As shown below, in the purported invention of the ’207 patent, lithium cells are “stacked in parallel to allow for larger capacity for different battery packs to be assembled.” Id. at 7:29-31.
The ’207 patent, Figs. 1, 2 (annotated).
The invention of the ’207 patent purportedly includes an auto-detect restart feature, which “protects the battery from a deep cycle discharge by monitoring battery voltage level and shutting the battery power off prior to a full discharge, such as in the case of leaving a headlight or electrical component on for an extended period of time while the engine is off.” The ’207 patent, 8:65-9:4. According to the ’207 patent, the auto-detect apparatus has at least “one lithium-based cell, a voltage detector, an associated switch such as a cutoff board, or a micro-controller in a balancing circuit connected to a solid state switch, such as an FET.” Id. at 9:8-12.
Figure 7 illustrates a block of 4 flat lithium based prismatic cells connected to a balancing circuit board 46, which has a balancing controller or microprocessor 60. Figure 8 illustrates a block of 4 flat lithium based prismatic cells connected to a balancing and cutoff circuit board 48, which includes a controller 60 and a solid state cutoff switch 62, such as an FET. The ’207 patent, 8:51-56.
The ’207 patent, Figs. 7, 8 (annotated).
As shown in Figure 9 below, the housing for the battery pack may include a positive terminal and a negative terminal. The ’207 patent, 8:56-58.
The ’207 patent, Fig. 9.
Claim 1 of the ’207 patent recites:
A battery pack having positive and negative terminals for powering an electric motor for starting an internal combustion engine in which the electric motor is in a 6 volt to 48 volt operating system, said battery pack comprising:
a battery pack housing;
at least one lithium-based rechargeable cell within said housing; and
a solid state switching apparatus comprising a plurality of pairs of solid state switches with one pair of solid state switches connected in a parallel configuration to another pair of solid state switches, each switch having a source and a drain, the switches of a pair of solid state switches being configured such that either the drains of the switches are connected or the sources of the switches are connected, and said parallel configuration being connected with one or more cells between the positive and negative terminals,
wherein a total discharging amount of each lithium-based cell in the battery pack is from 3 Ah to 2000 Ah, and charging voltage per one cell is 2.0 to 4.2 V.
The ’207 patent, 13:36-55.
Claim 1 of the ’994 patent recites:
A battery pack for driving an electrical device in a 12 volt to 120 volt operating system, said battery pack having a positive terminal and a negative terminal, comprising:
a battery pack housing having at least a first portion and a mating second portion;
at least one lithium-based rechargeable cell within said housing, each such cell having a positive pole and a negative pole;
a circuit board within said housing configured to balance each individual cell within said housing, and having a cutoff function incorporated therein, said circuit board including a plurality of pairs of solid state switches with each pair of solid state switches connected in a parallel configuration to another pair of solid state switches, each switch having a source and a drain, the switches of a pair of solid state switches being configured such that either the drains of the switches are connected or the sources of the switches are connected; and
said parallel configuration of the plurality of solid state switches being connected in series with said one or more cells between said positive and negative terminals of the battery pack.
The ’994 patent, 11:14-35.
Below are some of the accused products LithiumHub alleges as infringing both patents.
LithiumHub, LLC v. Shenzhen Fbtech Elecs. Ltd., Case No. 5:2024-cv-00133, Ex. E at 5 (E.D. Tex. Sept. 13, 2024) (purportedly charting accused product, the Dakota Lithium 12V 100AH Deep Cycle LiFePo4 Battery, against claims in the ’207 patent); id., Ex. D at 4 (purportedly charting the same product against claims in the ’994 patent); see also LithiumHub, LLC v. Shenzhen Yichen S-Power Tech Co., Ltd., Case No. 5:2024-cv-00137, Ex. E at 5 (E.D. Tex. Sept. 13, 2024) (purportedly charting the same product against claims in the ’207 patent); id., Ex. D at 4 (purportedly charting the same product against claims in the ’994 patent).
LithiumHub, LLC v. Shenzhen LiTime Tech. Co., Ltd., Case No. 5:2024-cv-00134, Ex. E at 5 (E.D. Tex. Sept. 13, 2024) (purportedly charting accused product, the LiTime 12V 100Ah Group 24 Deep Cycle LiFePO4 Lithium Battery, against claims in the ’207 patent); id., Ex. D at 4 (purportedly charting the same accused product against claims in the ’994 patent).
LithiumHub, LLC v. Relion Battery (Shenzhen) Tech. Co., Case No. 5:2024-cv-00135, Ex. J at 5 (E.D. Tex. Sept. 13, 2024) (purportedly charting accused product, RELiON RB100-HP, against claims in the ’207 patent).
LithiumHub, LLC v. Relion Battery (Shenzhen) Tech. Co., Case No. 5:2024-cv-00135, Ex. K at 6 (E.D. Tex. Sept. 13, 2024) (purportedly charting accused product, the Tracker Lithium Gen2 12.8V 52AH, against claims in the ’994 patent); see also LithiumHub, LLC v. Bass Pro Outdoor World LLC, Case No. 7:2024-cv-00220, Ex. F at 2 (W.D. Tex. Sept. 13, 2024) (purportedly charting the same accused product against claims in the ’207 patent); id., Ex. E at 3 (purportedly charting the same accused product against claims in the ’994 patent).
LithiumHub, LLC v. Renogy New Energy Co., Ltd., Case No. 5:2024-cv-00136. Ex. F at 3-5 (E.D. Tex. Sept. 13, 2024) (purportedly charting accused product, Renogy 12V 100Ah (RBT100LFP12S), against claims in the ’207 patent); id., Ex. E at 4 (purportedly charting the same accused product against claims in the ’994 patent).