Hyliion Holdings Corp. (HYLN) Business

ITEM 1. BUSINESS

Overview

Hyliion Holdings Corp. is a Delaware corporation headquartered in Cedar Park, Texas, with research and development (“R&D”) facilities in Cincinnati, Ohio, that designs and develops power generators for stationary and mobile applications and provides R&D services. References to the “Company,” “Hyliion,” “we,” or “us” in this report refer to Hyliion Holdings Corp. and its wholly owned subsidiary, unless expressly indicated or the context otherwise requires. The Company was incorporated on November 7, 2018 and is listed on the NYSE American.

Hyliion is committed to creating innovative solutions that enable clean, efficient, and flexible electricity production while contributing positively to the environment in the energy economy. Hyliion’s primary product offering, the KARNO Power Module, is a modular, fully enclosed, fuel-agnostic and fully integrated power generating solution. The KARNO Power Module is powered by KARNO Core, a heat powered linear generator, to produce electricity with significant improvements in efficiency, emissions and lifecycle cost compared to conventional generation technologies. Hyliion’s KARNO Power Modules enable effective power generation using a wide range of fuel sources, including conventional fuels such as natural gas, propane or diesel, waste fuels such as landfill gas, wellhead gas, and zero carbon fuels such as renewable hydrogen and ammonia. Hyliion is initially targeting the datacenter, commercial, industrial, and defense sectors with a locally-deployable generator designed to meet a wide range of power generation needs. The Company plans to scale up its KARNO Power Module solution to address larger utility-scale power needs and to develop future variants for industrial waste heat, nuclear, household use and e-mobility applications such as vehicles and marine vessels. Additionally, the KARNO Power Module technology is well-suited to provide combined heat and power in various stationary applications.

Strategic Business Developments

In July 2025, the Company was awarded a Phase II Small Business Innovation Research (“SBIR”) best effort cost-plus-fixed fee contract up to $1.5 million by the United States Department of the Navy’s Office of Naval Research (“ONR”). This latest award builds upon previous contracts with ONR to assess the suitability of the KARNO Power Module for Navy vessels and stationary power applications, including a contract for up to $16 million awarded in 2024 and two earlier contracts for up to $2.4 million. Phase I of the SBIR contract focused on developing a liquid-fueled 2 MW power generation system and optimizing the layout to produce the required power output within the available footprint. The latest award addresses two core capabilities: an integrated drive concept that reduces system packaging by mounting key subassemblies directly to the engine, and a multi-KARNO communication and software architecture that enables multiple cores to operate as a single, stable 2 MW system. We believe that together, these efforts advance the technical feasibility of full-scale system development. Under the agreement, the Company will provide R&D services through July 2026 with an option to extend through July 2027, including design reviews, simulations, and reporting.

Products and Services

KARNO Power Modules

The KARNO technology emerged out of General Electric’s long-running R&D investments in aerospace and metal additive manufacturing across multiple industries and in areas such as generator thermal and performance design. We initially envisioned utilizing the KARNO Core as new range-extending power source for our Hypertruck powertrain system, given its ability to operate on a wide range of fuel sources, including natural gas and hydrogen. After the previously-announced wind down of our powertrain operations, we shifted our focus to the development and commercialization of the KARNO Power Module as a standalone product targeting power generation and e-mobility markets, and related R&D services that we have undertaken pursuant to contracts with the United States government. We believe that the unique capabilities of the KARNO Power Module will make it competitive in the market for distributed power systems, competing favorably against conventional generating systems and new alternative power systems such as fuel cells and other linear generators. The KARNO Power Module and KARNO Core technology, including the technology that we acquired from General Electric, and the technology developed by Hyliion subsequent to the acquisition, is protected by numerous patents and trademarks which we believe provide us with extensive and lasting protection for our intellectual property.

The Science of the KARNO Power Module

The KARNO Power Module is distinguished from conventional generating systems that rely on reciprocating internal combustion engines or gas turbines to drive a rotating shaft. Instead, the KARNO Core that powers the KARNO Power Module uses an innovative thermal converter to power a linear electricity generating system. The KARNO Core produces linear motion from temperature differences within the system. Heat is generated through flameless oxidation of fuels, such as natural gas, hydrogen, or propane. The thermal energy heats helium gas enclosed within a sealed cylinder, causing it to expand and drive linear motion in a connected piston-shaft system. The shaft includes a sequence of permanent magnets that pass through

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electrical coils as the system oscillates, generating electricity. Subsequently, the countermotion generated by a piston at the opposite end of the shaft flows the helium gas to the cold side of a piston in an adjacent shaft, where excess heat is efficiently dissipated. This cyclical process continues, resulting in a continuous source of electrical power as long as heat is supplied to the KARNO Core.

Linear generators present several advantages over conventional generators, including higher thermal efficiency, lower emissions and reduced maintenance, benefits that are partly attributable to the generator’s simplified design with few moving parts. Additionally, they exhibit high power density and higher efficiency by circumventing the mechanical losses linked to rotating components such as bearings and gears while producing less noise and vibration. In the case of the KARNO Core, each shaft relies on a single moving part and utilizes a pressurized helium bearing system in place of oil-based lubricants.

Thermal converters offer the advantages of fuel flexibility and high operating efficiency. The KARNO Core stands out for its ability to maximize heat transfer between components and working fluids. Enabled by advances in additive manufacturing systems, parts are designed with many intricate flow channels for the movement of heat, coolant, helium and exhaust gases such that contact surface areas for heat transfer are maximized. This enables the KARNO Power Module to achieve high levels of efficiency.

The KARNO Power Module is expected to surpass the efficiency of many conventional generating systems when employing various fuel sources and its high efficiency is expected to remain consistent across a broad range of output power levels. In comparison, fuel cells reach peak efficiency at low power levels but experience diminishing efficiency as output increases towards full power. Internal combustion engines typically achieve peak efficiency within a limited operational output range and may suffer increased wear at low power levels. The KARNO Power Module offers a distinct advantage in power adjustment by modulating the rate of heat introduction, enabling seamless power adjustments without compromising efficiency.

We anticipate that the KARNO Power Module will initially achieve an electrical generating efficiency of approximately 45%, calculated by considering the usable power output in relation to the energy from the fuel source. We believe that ongoing engineering improvements are expected to increase the KARNO Power Module’s efficiency to 50% or higher in future design iterations. High efficiency is expected to remain relatively consistent across a wide range of output power levels, spanning from tens of kilowatts to multiple megawatts. In contrast, internal combustion diesel or natural gas generators typically operate within an efficiency range of 25% to 40% over a similar power spectrum, while the U.S. electrical power grid is estimated to operate at an efficiency between 33% and 40%. Notably, best-in-class grid-level combined cycle gas turbine powerplants can obtain efficiencies above 50% but often incur transmission and distribution losses between 5% and 10% which the KARNO Power Module is expected to circumvent by being located near the point of power consumption.

Conventional generators emit pollutants because of incomplete combustion of fuel-air mixtures and operating conditions, with the formation of nitrous-oxide (“NOx”) and carbon monoxide (“CO”) compounds being particularly prominent. Unlike conventional generators, the KARNO Power Module is designed for continuous flameless oxidation of the fuel at lower temperatures and extended reaction times. This is achieved partly through the recirculation of exhaust gases, which serves to prolong oxidation, and by pre-heating incoming air. As a result, the KARNO Power Module is anticipated to achieve ultra-low levels of emissions, with NOx and CO emissions expected to be reduced by over 95% compared to best-in-class diesel or natural gas engines and meeting South Coast Air Quality Management District (“SCAQMD”) Rule 1110.3 emission standards without the need for aftertreatment.

One of the notable advantages of the KARNO Power Module in comparison to traditional generating units is the expected reduction in maintenance requirements and cost. Conventional generators typically incur periodic and usage-based maintenance expense that can range between 5% to 20% of their total operating cost throughout their lifespan, influenced by factors such as utilization and operating parameters. The KARNO Power Module’s primary advantage arises from having only a single moving part per shaft (4 shafts per 200 kW KARNO Core), which glides on low friction helium bearings. This innovative design significantly mitigates efficiency losses attributed to friction, enhancing the system’s operational longevity and eliminating the need for oil-based lubricants.

The KARNO Power Module derives advantages from its expected capability to operate across a diverse spectrum of over 20 available fuel sources and fuel blends. These include natural gas, propane, gasoline, jet fuel, and alternative fuels like biodiesel, hydrogen and ammonia. Moreover, the KARNO Power Module can seamlessly transition between these fuels or fuel blends. This versatility enables a single KARNO Power Module to adapt to different use cases. For example, the KARNO Power Module may operate on natural gas for prime power generation when a pipeline connection is available, on waste gas near a landfill or dairy farm, and switch to locally stored diesel fuel for continuous generation if its primary fuel supply is interrupted. Furthermore, as hydrogen becomes more widely available, the KARNO Power Module will be able to adapt to this cleaner fuel.

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As the energy landscape evolves, the KARNO Power Module’s fuel-agnostic nature positions it as a flexible solution to electricity generation needs, enhancing energy security.

Benefits of the KARNO Power Module Versus Conventional Competitors

We believe the versatility and operating characteristics of the KARNO Power Module make it an effective system for a variety of conventional and emerging electricity generating applications. Key attributes of the KARNO Power Module distinguish it from its conventional generator counterparts, which may open new market opportunities:

•Efficiency: The anticipated operating efficiency of the KARNO Power Module could result in lower marginal cost of electricity generation versus conventional generating systems and, in some markets, grid power.

•Low Maintenance: With only a single moving part per shaft, the simplicity of the KARNO Power Module is expected to reduce both periodic maintenance expenses and overhaul costs and deliver longer uptime.

•Fuel Agnostic: While many traditional generators operate on a single fuel source or require system modification to achieve fuel flexibility, the KARNO Power Module is truly fuel-agnostic and can switch between fuel choices during operation with few or no modifications.

•Low Noise and Vibration: Unlike conventional generators, the KARNO Power Module operates without internal combustion, resulting in a significantly lower noise level of approximately 67 decibels at six feet.

•Higher Power Density: The unique architecture and features of the KARNO Power Module that are achieved by advances in additive manufacturing are expected to enable the KARNO Power Module to achieve a higher power density.

•Modularity: The DC output of the KARNO Power Module allows multiple KARNO Power Modules to be connected on a single bus to achieve higher power outputs without impacting other performance characteristics.

Market Opportunity

As economies and industries evolve, the demand for electricity is accelerating, driven by the electrification of society, urbanization, increasing industrial output and technological growth. Electricity powers factories, drives the digital revolution, supports healthcare, education, and financial services, and serves as the foundation of economic productivity. Additional growth drivers include the widespread adoption of automation, artificial intelligence, expanding data centers and the electrification of transportation. However, as global energy demand rises, traditional centralized power generation and distribution models face mounting challenges.

The aging of grid transmission infrastructure is creating new challenges as operators work to balance the availability of affordable, reliable power with maintaining grid stability and integrating new sources of clean power generation. The addition of intermittent renewable power generation further complicates grid management, emphasizing the need for resilient and adaptive electricity systems. Distributed power generation offers a solution by decentralizing electricity production, reducing transmission needs and delivering power closer to points of consumption.

We believe that Hyliion’s KARNO Power Module is an innovative solution in the emerging distributed generation space, offering a reliable power generator that combines high efficiency, fuel flexibility, and low emissions. Designed for both stationary and mobile applications, the KARNO Power Module addresses many of the challenges that have traditionally limited the widespread adoption of onsite power solutions. These include high operating costs, reliability issues, complex maintenance, noise pollution, space constraints, and dependency on limited fuel sources.

Hyliion’s initial KARNO Power Module product is a 200 kW system that is power-dense and easy to deploy. It features a compact, space-efficient rectangular design with a footprint of approximately 25 square feet, housing a single four-shaft linear generating unit and integrated balance-of-plant components. The KARNO Power Module supports fuel switching during operation without power loss, while flexible deployment options allow it to operate in grid-following, grid-forming, or islanded configurations (when paired with an external inverter), making it suitable for a wide range of applications. Additionally, the KARNO Power Module features real-time monitoring of over 1,000 operational parameters through its KARNO Cloud® platform, enabling proactive diagnostics, predictive maintenance, and performance optimization, ensuring maximum uptime. With cloud connectivity, users gain instant access to remote monitoring and control features, providing insights into system performance, fuel efficiency, and system health.

Beyond the 200 kW variant, Hyliion is advancing the development of a larger Multi-MW (2 MW+) KARNO system, which integrates multiple 200 kW KARNO Core units operating in tandem in a compact containerized footprint. The Multi-MW solution will target key market segments such as data centers and industrial prime power applications. We are also developing a modular 800 kW system consisting of four KARNO Core units that is planned to be delivered to the U.S. Navy in 2026 as part of our project with ONR. We believe that this modular and scalable approach enables seamless power expansion while

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maintaining high efficiency and reliability. By utilizing multiple 200 kW generating blocks, the system offers built-in redundancy and the flexibility for customers to customize capacity to match their power needs.

Hyliion also plans to expand the KARNO product line with both larger and smaller capacity versions, adjusting power levels by varying the number of generator shafts and component sizes. Initially, the KARNO Power Module will address power applications ranging from 200 kW to the low megawatt range, addressing a broad spectrum of distributed generation needs. With its ability to deliver reliable, fuel-flexible, and highly efficient power, the KARNO Power Module is uniquely positioned to serve a variety of key market segments, including:

•Data Centers: As cloud computing, artificial intelligence, machine learning, and edge computing continue to expand, data centers are projected to grow rapidly, consuming an increasing share of global energy demand. Onsite generation is an emerging solution to power new data center installations. Hyliion’s Multi-MW KARNO system is being designed to address the needs of data center developers by providing a scalable, fuel-flexible onsite power solution with best-in-class power density and versatility. Capable of operating on more than 20 different fuels, the KARNO Power Module enables data center developers to minimize onsite generation infrastructure. Its ability to easily transition between pipeline-supplied fuels, such as hydrogen or natural gas, and onsite stored fuels, like methanol or diesel, eliminates the need for separate backup generation systems, reducing capital and operational costs. As datacenter rack power densities rise to support increased AI workloads, Hyliion’s KARNO Power Module’s native 800V DC architecture simplifies power system design and enhances site resiliency.

•Commercial & Industrial: As electricity demand increases and grid infrastructure struggles, microgrids and onsite prime power solutions are becoming essential for industries facing high consumption charges, peak demand pricing, and grid reliability concerns. Businesses, industrial sites, and remote facilities increasingly seek localized power generation to mitigate rising energy costs, monetize assets, and improve operational resilience. With relatively high efficiency, fuel adaptability and low maintenance needs, KARNO Power Modules provide a cost-effective alternative to grid electricity, allowing businesses to optimize energy costs while ensuring uninterrupted operations. Its ability to seamlessly integrate with energy storage and renewable sources enables installation of effective hybrid energy solutions. Additionally, the KARNO Power Module’s cogeneration capabilities allow industries to utilize both electricity and thermal energy, improving overall system efficiency and recovering usable waste heat.

•Defense: Defense organizations around the world are pursuing advanced energy solutions to support modern, rapidly evolving, distributed operations across land, sea, air, and autonomous platforms. Hyliion’s fuel-agnostic KARNO platform is engineered to meet these changing mission profiles with a combination of versatility, efficiency, and durability. Designed to operate on over 20 fuels, including JP-8 and its variants, diesel, ammonia, and hydrogen, the KARNO system enhances logistical adaptability across diverse applications. Its low acoustic and thermal signatures support stealth and operational security, while its high fuel efficiency enables longer runtimes and reduced refueling needs. Built with minimal moving parts and robust architecture, the KARNO technology delivers extended maintenance intervals and high system uptime under challenging conditions. Whether deployed in forward operating bases, shipboard power systems, microgrids, or unmanned autonomous platforms, the scalable KARNO Power Module can deliver reliable, next-generation power for the strategic and tactical demands of global defense operations.

•Vehicle Charging: The adoption of electric vehicles (“EVs”) is placing increasing strain on grid capacity, a challenge expected to grow with the introduction of commercial EVs, including buses, delivery vans, and heavy-duty trucks. These vehicles require substantial power for charging, intensifying grid demands. While Direct Current (“DC”) fast charging technology and infrastructure are evolving to meet this need, many commercial operators cite limited grid capacity and high electricity costs as barriers to scaling their EV fleets. Hyliion’s KARNO Power Module offers an advantaged solution for commercial EV charging. Its native DC output integrates seamlessly with DC fast charging infrastructure, eliminating power losses associated with conversion. Additionally, the KARNO Power Module’s compact footprint and quiet operation make it ideal for deployment in space-constrained locations, such as urban charging hubs, fleet depots, and remote charging stations where grid access is limited or expensive. When paired with onsite energy storage systems and renewable energy sources like solar or wind, KARNO Power Modules can enable resilient and sustainable microgrids for EV charging.

•Biogas (Landfill, Wastewater & Digester Gas): Biogas sourced from landfills, wastewater treatment plants, and dairy digesters represents a growing market as industries and municipalities seek to convert methane-rich waste gases into electricity and prevent methane, a potent greenhouse gas, from escaping into the environment or being flared. Current power generation technologies often struggle to process biogas due to contaminants such as hydrogen sulfide and siloxanes, as well as moisture and fluctuating gas compositions, necessitating preconditioning and purification before the fuel can be utilized. The KARNO Power Module’s advanced architecture and corrosion-resistant materials enable

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it to operate with minimal gas preconditioning, making it a cost-effective, high-performance solution for converting waste gas into reliable power.

•Oil & Gas and Syngas Gas: The oil and gas industry is rapidly electrifying due to growing power needs across drilling, production, refining, and transportation operations. However, wellhead and flare gas, byproducts of oil and gas extraction, are often wasted due to insufficient pipeline capacity or poor gas quality, leading to lost energy and increased emissions. The KARNO Power Module enables conversion of waste gas into usable electricity with minimal pre-treatment, enabling onsite power generation and grid integration. Its fuel flexibility, use of corrosion-resistant materials, and ability to handle variable fuel quality make it an ideal technology of choice for oilfield electrification while significantly reducing emissions. Additionally, the KARNO Power Module’s fuel-agnostic capability allows it to generate clean electricity from hydrogen-rich syngas, a valuable byproduct of gasification or industrial processes.

•Mobility: The KARNO Power Module is particularly suitable for applications that require a source of electric power in mobile applications such as electric vehicles, railroad locomotives, remote power generation and marine vessels. Compared to conventional power sources, the KARNO Power Module is expected to offer higher efficiency, lower emissions, quieter operation, reduced maintenance needs and the flexibility to operate on a wider range of fuel sources. Additionally, the KARNO Power Module’s high power density, modularity and native DC power output offers an added advantage where space constraints and integration are considerations.

•Backup Power: The market for local backup power generators is well established and positioned to grow due to decreasing grid reliability, the increasing share of intermittent renewable energy sources, rising extreme weather events, and the need for uninterrupted power. Also, the grid balancing and servicing market is expanding as utilities and independent power producers seek fast-ramping, distributed generation assets to balance supply and demand fluctuations. Innovative business models such as Resiliency-as-a-Service and Virtual Power Plants have emerged to leverage distributed generation assets for grid resilience. With growing concerns over emissions from internal combustion engine-powered generators in the backup power market, we believe the KARNO Power Module presents an opportunity to provide solutions for end users that desire a lower emissions profile and in the event emissions regulations are further tightened.

•Waste Heat: In hard-to-decarbonize industrial sectors such as cement, glass, and primary metals production, vast amounts of high-grade waste heat (1000°C+) are released during manufacturing processes. Traditionally, much of this thermal energy is lost due to limited efficient recovery solutions. Since the KARNO Power Module uses heat as its primary energy source to generate electricity, high-temperature industrial waste heat is expected to be able to be directly utilized to produce clean electricity, enabling industries to recover wasted energy, improve efficiency, and reduce emissions.

KARNO Power Module Development

Research and Development

Most of our current activities are focused on the R&D of our KARNO Power Module. We undertake significant testing and validation of our products and components to ensure that they will meet the demands of our customers. Our R&D activities primarily take place at our facility in Cincinnati, Ohio and at our headquarters in Cedar Park, Texas. Our R&D is primarily focused on:

•development of the KARNO Core and Power Module including testing and validation;

•integration of the KARNO Core and Power Module technology into various applications;

•accelerated lifetime testing to improve reliability, maintainability and system-level robustness;

•development of battery systems that can be used as a starter power source for the KARNO Power Module or as a load buffer solution;

•data analytics; and

•alternative products for existing and in-development components and technology.

Since acquiring the KARNO technology from GE in September 2022, Hyliion has made significant R&D investments to support a commercial launch of the 200 kW KARNO Power Module. Early efforts focused on the development of a 125 kW KARNO Core, which has been successfully operated in our Ohio facility and utilized for extensive testing and further advancements. Through this system, we validated the ability of the KARNO Core’s fuel oxidation system to operate on a wide range of fuel sources, including natural gas, hydrogen, gas mixtures, and untreated landfill and Permian Basin well gas. Additionally, testing of the oxidation system demonstrated very low levels of pollutant emissions in the exhaust stream. The 125 kW KARNO Core also served as platform for developing and validating key components that are now incorporated into the larger 200 kW KARNO Power Module slated for market launch. These advancements include improved helium gas bearings

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for greater durability, a magnetic encoder for precise shaft position detection and optimized printed components to increase KARNO Core efficiency and manufacturing speed. The higher powered 200 kW KARNO Core also incorporates a larger Hyliion-designed linear electric motor. R&D activities in 2024 and 2025 included developing production processes for this new motor as well as testing and validation of system design parameters.

We have completed the design and sourcing of components for the balance-of-plant systems that support KARNO Core operation for the 200 kW system, including the system enclosure. The balance-of-plant includes cooling, pressure control, fuel, battery, high and low voltage, inlet air and exhaust systems. Development work also includes control software, safety systems, the human-to-machine interface and the physical integration of systems. Validation of essential operating parameters, including efficiency, emissions and reliability, are also part of R&D activities.

In 2025, we delivered two early adopter customer units to the U.S. Navy as well as two additional KARNO Power Modules that we are using for internal testing and Underwriters Laboratories (“UL”) certification. The U.S. Navy units are undergoing testing under our R&D contract with ONR and are performing in accordance with expectations mechanically while we enhance the ability of the units to operate on diesel fuel. We believe that initial KARNO Power Module deployments, along with our ongoing testing and development efforts, will validate critical design specifications, including projected operating life, maintenance requirements and durability.

In early 2025, we announced that delivery of early deployment customer units and validation of KARNO Power Module design parameters were delayed due to design and production problems related to a key printed component − the regenerator − as well as delays in ramping up production of linear electric motors by a contract manufacturer. The regenerator functions as a heat capacitor, storing thermal energy within the system as helium gas cycles between hot and cold temperature regions. It is a critical component for achieving the KARNO Power Module’s target power levels and overall system efficiency. An early regenerator design was found to have insufficient heat storage and transfer capability. Additionally, residual powder from the additive manufacturing process could not easily be removed after printing due to the small passageways in the regenerator’s flow channels.

The regenerator has since been redesigned to increase heat storage and transfer capability. Testing of the updated design demonstrated significant performance improvement compared with the earlier configuration. While the improved thermal characteristics enhanced overall performance, testing also identified other areas where heat losses within the system were adversely affecting results. Design modifications have been implemented to increase the insulative properties of other system components with improved performance observed during subsequent testing. Further design modifications to the regenerator and other components are now under way to enable even greater conversion of heat losses into higher power output and improved efficiency. Furthermore, new post-processing techniques have been implemented and verified to effectively remove residual powder from regenerators after printing.

In mid-2025, we decided to insource linear electric motor production following earlier unsuccessful efforts to outsource this work to a contract manufacturer. This transition is accelerating the ramp-up in motor production capacity and enabling greater control over manufacturing quality. While production challenges and the shift in operations delayed early deployment deliveries, output has since increased and is now expected to meet ongoing production needs.

Research and Development Services

We provide R&D services to third parties, including the ONR. In September 2024, Hyliion was awarded a cost-plus-fixed-fee contract of up to $16.0 million by the ONR to assess the suitability of its KARNO Power Module for Navy vessels and stationary power applications. The contract aligns with ONR’s objective of leveraging advanced technology to reduce its carbon footprint while enhancing operating capabilities. Upon successful validation and demonstration, the KARNO Power Module could be used as an electric power system in future platforms and for stationary power needs. In 2025, we delivered two KARNO Cores under this contract which we have been testing at our R&D facility in Cincinnati. We expect to deliver additional KARNO Cores, including a four-core 800 kW KARNO Power Module system, and 200 kW KARNO Power Modules during 2026. We will also expand testing to include long duration operation, diesel fuel integration, simulation of ship motion and the ability of the system to operate in extreme temperature environments.

We will continue to provide R&D services to third parties under existing contracts and anticipate entering into additional R&D agreements in 2026 with ONR and other government customers. Customers engage Hyliion to explore and validate the KARNO Power Module’s capabilities tailored to their specific requirements. Key areas of interest include testing its low-emissions flameless oxidation system and evaluating applications that leverage the KARNO Power Module’s high power output, compact configuration and versatility, including the ability to easily transition between fuels. R&D services may also involve testing the KARNO Power Module under various operating conditions, including harsh environments, and in mobile

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applications to assess its performance. Certain customers seek to measure and validate its low emissions profile and test different power configurations to ensure the technology aligns with their operational and environmental needs.

Commercial Deployment

We expect to continue delivering KARNO Power Modules to early deployment customers throughout 2026. These deployments, combined with our ongoing internal R&D efforts, will serve to test and validate the product’s attributes while identifying potential design and software enhancement opportunities. We expect to receive compensation for these deployments as outlined in customer contracts subject to achievement of certain key performance indicators, given the tangible benefits the KARNO generator is expected to deliver.

Initial KARNO Power Modules are expected to receive UL certification for operation up to 150 kW as we continue to implement engineering modifications to increase heat capture, power output and efficiency. We expect to achieve UL certification at the full design power of 200 kW prior to the planned commercialization of the KARNO Power Module later in 2026. In addition, initial generator configurations may not support all contemplated fuel types, as fuel capability is expected to be offered as a configurable option for customers. We expect initial deployment applications to include military uses, vehicle charging, commercial applications, and datacenter integrations. These early deployments are also likely to highlight opportunities for achieving hardware and software improvements, as well as potential enhancements to further refine and optimize the product.

In 2026, additional development activities will focus on implementing engineering solutions to enhance the KARNO Power Module’s power level, efficiency and operational durability. These efforts may include design modifications, including for additively-manufactured parts, changes to and procurement of purchased components, and further software development. We plan to address these enhancements in parallel with the rollout of early deployment units and the ongoing testing of in-house engineering development generators. While the full scope of additional development work is difficult to predict at this stage, we currently anticipate completing these improvements throughout the year, leading to our ability to achieve product commercialization before the end of 2026, at which point we expect to ramp up delivery of KARNO generators to commercial customers.

Assuming we meet the expected timing of the commercialization of the KARNO generator, we anticipate sales growth in 2027 and beyond as we address the backlog of customer interest based on signed contracts and letters-of-intent. This growth is expected to be supported by the commissioning of new additive printers installed during 2025, as well as additional units expected to be delivered in 2026. We also plan to increase output from our existing installed printer base by optimizing key print parameters that influence part print time and quality, including laser speed and motion profile, power level and powder penetration depth. In addition, we expect to begin testing new laser technology anticipated to become available with certain future printer models and, in some cases, to be retrofitted into our existing printer fleet. Finally, we plan to expand our sales, distribution and service networks to support the generator’s expected growing market presence. Currently, these functions are managed in-house to ensure efficient delivery and service for our customers; however, we may explore outsourcing or partnerships with established sales, service and distribution channels as we scale operations.

Production, Assembly, Installation and Suppliers

The standalone KARNO Power Module, or genset system, integrates the KARNO Power Module with an enclosure housing key balance-of-plant components such as the cooling system, generator controls, a battery system and high voltage electrical elements. The planned 2+ MW KARNO system is expected to feature ten or more 200 kW KARNO Power Modules combined with shared balance-of-plant systems in a compact configuration. Key KARNO Power Module components will initially be produced internally using advanced additive manufacturing processes, while other components will either be manufactured in-house or sourced from suppliers following proprietary Hyliion designs. Hyliion is actively developing a base of suppliers for KARNO Power Module systems, including linear motor components, support systems and enclosure materials. Initially, the assembly, installation and maintenance of KARNO Power Module systems will be performed by Hyliion.

Additive manufacturing is a key enabler of KARNO Power Module technology and performance characteristics and is considered a core competency of Hyliion as well as a source of competitive advantage versus other linear power generating systems. Beginning in 2024, Hyliion began procurement of state-of-the-art laser sintering machines (3-D additive printers) manufactured by GE to build out print capacity at our Cedar Park, Texas facility. Hyliion’s R&D facility in Cincinnati also houses additive printers that support R&D activities and commercial production needs. Hyliion has placed orders with GE for additional additive printing machines, which are expected to be delivered in 2026, providing a growing base of print production capacity.

Advancements in additive printer technology are expected to grow over time, driven by improvements in laser technology and other print innovations. New printer models are expected to offer progressively greater printing speed, with some enhancements potentially available as retrofits for existing machine platforms. In parallel, we are pursuing design modifications to enable the production of components with less complex geometry using conventional manufacturing processes, reducing reliance on

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additive printing where feasible. For less critical components, we are exploring utilization of lower-cost and lightweight materials like aluminum and stainless steel. Additionally, as production volumes increase, we expect economies of scale to contribute to reduced system component costs, enhancing the overall competitiveness of the KARNO Power Module.

Hyliion currently plans to print key KARNO Power Module components in-house for early system deployments to optimize production parameters, component quality, printing innovation and system throughput. As production volumes rise, we may consider outsourcing certain production and assembly functions including the printing, manufacturing and assembly of specific components or the entire generator to third parties.

Suppliers of generator components include fabricators, machine shops, suppliers of mechanical and electrical components like pumps, blowers, tubing and wiring harnesses, as well as metal powder manufacturers. The majority of these components are sourced domestically, supported by a large network of available vendors. We source some components from overseas suppliers, including magnets and battery cells, due to cost advantages or limited domestic availability. We are currently experiencing limitations on the importation of high strength rare earth magnets that we previously sourced from China. We are developing supply chain solutions to address these constraints and expect to secure magnet supply in sufficient quality and quantity to meet our future requirements. In parallel, we are actively pursuing domestic sourcing alternatives, although traditional suppliers often have limited available quantities or are unable to deliver magnets with the strength required for our applications. As we scale production capacity, we plan to broaden our supplier base to achieve cost efficiencies and mitigate supply chain risk.

Intellectual Property

Intellectual property is important to our business, and we seek protection for our strategic intellectual property. We rely upon a combination of patents, copyrights, trade secrets, know-how and trademarks, along with employee and third-party non-disclosure agreements and other contractual restrictions to establish and protect our intellectual property rights.

As of December 31, 2025, we had 73 issued U.S. patents, 16 pending U.S. patent applications, 32 foreign patents, and 21 foreign patent applications. Of the foregoing patent and application totals, 90 pertain to our KARNO generator and the remainder primarily relate to powertrain technology, which we may retain for potential future use or sale. We pursue the registration of our domain names, trademarks and service marks in the United States and in some locations abroad. In an effort to protect our brand, as of December 31, 2025, we had five pending trademarks in the United States and 40 registered trademarks internationally.

We regularly review our development efforts to assess the existence and patentability of new intellectual property. To that end, we are prepared to file additional patent applications as we consider appropriate under the circumstances relating to the new technologies that we develop. Generally, our patents have a term of 20 years from the date the application is filed.

We cannot be sure that patents will be granted with respect to any of our pending patent applications or with respect to any patent applications we may own or license in the future, nor can we be sure that any of our existing patents or any patents we may own or license in the future will be useful in protecting our technology.

Human Capital

As of December 31, 2025, we had approximately 113 full-time employees. All full-time employees are located within the United States. Our people are integral to our business, and we are highly dependent on our ability to attract, engage, develop and retain key employees while hiring qualified management, technician, and engineering personnel. We value having a wide range of skills, perspectives and experiences across our workforce and encourage the collaboration and integration of individual strengths and ideas. By fostering a collaborative and respectful culture, we enable every member of the workforce to leverage their unique talents and deliver high performance standards to drive innovation and success.

Government Regulations

We operate in an industry that is subject to extensive environmental regulation, which has become more stringent over time. The laws and regulations to which we are subject govern, among others:

•water use;

•air emissions;

•energy sources;

•the storage, handling, treatment, transportation and disposal of hazardous materials;

•the protection of the environment; and

•natural resources.

We may be required to obtain and comply with the terms and conditions of multiple environmental permits, many of which are difficult and costly to obtain and could be subject to legal challenges. Compliance with such laws and regulations at an

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international, regional, national, provincial and local level is an important aspect of our ability to continue operations and grow the business. Environmental standards applicable to us are established by the laws and regulations of the countries in which we operate, and our product are sold, and standards adopted by regulatory agencies and the permits and licenses that we hold. Each of these sources is subject to periodic modifications and increasingly stringent requirements. Violations of these laws, regulations, or permits and licenses may result in substantial civil and criminal fines, penalties, orders to cease the violating operations, or to conduct or pay for corrective works. In some instances, violations may also result in the suspension or revocation of permits and licenses.

Specific standards, certifications, and rules for which we seek to be in compliance include the following:

•Military Standard (“MIL-STD”) 1399 requirements over power quality;

•MIL-STD-810, MIL-STD-901, and MIL-STD-167 requirements over shock and vibrations;

•MIL-STD-810G requirements over environmental exposure;

•UL 2200, 1004, 1973, and 1741 requirements over generator set, electric machine, battery, and inverter safety, respectively;

•Institute of Electrical and Electronics Engineers (“IEEE”) 1547 and 519 requirements over grid interconnection and harmonic control, respectively, with optional external inverters;

•South Coast Air Quality Management District (“SCAQMD”) in California Rule 1110.3, the first of its kind regulation focused on linear generators, “Emissions for Linear Generators.” This rule governs, among other things, the steady state emissions from technologies such as the KARNO generator. We work closely with SCAQMD to help evaluate the various criteria and as a result, believe that the KARNO generator will comply with this regulation;

•Environmental Protection Agency Clean Air Act regulatory standards which mandate strict controls on emissions to ensure compliance with environmental protection guidelines;

•CARB Distributed Generation Certification standards which impose stringent emission limits and performance criteria to protect air quality and public health standards; and

•National Fire Protection Association (“NFPA”) 37, Standard for the installation and Use of Stationary Combustion Engines and Gas Turbines.

Competition

We have experienced, and expect to continue to experience, competition from a number of companies. We face competition from many different sources, including utility-scale grid power and manufacturers of fixed and portable generator equipment. Key generator manufacturing competitors include Cummins, Bloom Energy, Generac, Rehlko (formerly Kohler), Caterpillar, Mainspring and Jenbacher, several of which maintain the largest market shares in the sector. We believe the primary competitive factors in the stationary generator market include, but are not limited to:

•total cost of ownership;

•emissions profile;

•availability of fueling sources;

•ease of integration into existing operations;

•product performance and uptime; and

•generator quality, reliability, safety and noise.

We believe that we compete favorably with our competitors on the basis of these factors; however, most of our current and potential competitors have greater financial, technical, manufacturing, marketing and other resources than us. Our competitors may be able to deploy greater resources to the design, development, manufacturing, distribution, promotion, sales, marketing and support of their generator products. Additionally, our competitors also have greater name recognition, longer operating histories, larger sales forces, broader customer and industry relationships and other tangible and intangible resources than us. These competitors also compete with us in recruiting and retaining qualified R&D, sales, marketing and management personnel, as well as in acquiring technologies complementary to, or necessary for, our products. Additional mergers and acquisitions may result in even more resources being concentrated in our competitors. We cannot provide assurances that our stationary generators will be broadly adopted or will provide benefits that overcome their capital costs.

We also face competition in the market for R&D services from companies that specialize in the design, development and testing of electric generator systems and components and other engineering services. However, we believe that we are well-positioned to compete effectively in this space, as our R&D customers engage us specifically to deliver and perform testing and validation

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work on the KARNO Power Module. Unlike our competitors, who lack access to the KARNO Power Module’s technology and capabilities, we can provide a combination of product delivery and specialized testing services that our customers are seeking.

Information About Our Executive Officers

The following table and notes set forth information about our executive officers:

1 Mr. Healy has served as our Chief Executive Officer since October 2020 and prior to this, served as Chief Executive Officer of Hyliion Inc., (“Legacy Hyliion”) since January 26, 2016. While leading the Company, Mr. Healy has been awarded numerous patents and accolades for his leadership of Hyliion. Mr. Healy founded Legacy Hyliion while studying to obtain a Master’s in mechanical engineering and had previously founded multiple start-ups during his undergraduate studies. He took a leave of absence during his Master’s program in 2015 to found Legacy Hyliion. Mr. Healy holds a B.S. in mechanical engineering with a double-major in engineering and public policy from Carnegie Mellon University. In 2023, Mr. Healy was invited to join the Carnegie Mellon University Board of Trustees, where he continues to serve.

2 Mr. Panzer has served as Chief Financial Officer since September 2022. Prior to joining Hyliion, Mr. Panzer spent 26 years at Union Pacific, one of the nation’s largest railroads. His most recent position at Union Pacific was Senior Vice President of Intermodal Operations and he also served as Senior Vice President of Technology and Strategic Planning, Vice President and Treasurer, Vice President, Financial Planning and Analysis, and Assistance Vice President, Marketing and Sales. As head of Union Pacific’s information technology organization, Mr. Panzer was responsible for managing application development, technology infrastructure and cybersecurity. Prior to joining Union Pacific, Mr. Panzer served in the United States Navy as a nuclear engineer. Mr. Panzer holds a B.S. in electrical engineering from the University of Nebraska, Lincoln and an MBA from Carnegie Mellon University.

3 Ms. Lantz has served as Chief Strategy Officer since 2022. Ms. Lantz is a seasoned strategy leader who has spent 25 years developing and leading operations and growth strategies for manufacturers in the mobility sector. Prior to joining the Company, Ms. Lantz served as the Vice President of Strategy for the Transportations Solution Segment at TE Connectivity, an electronics manufacturer. Prior to that role, Ms. Lantz served as the Chief Strategy Officer and executive leader responsible for advanced and shared engineering and global test labs at Meritor, Inc., a leading manufacturer of axles and brakes to the commercial vehicle industry. Additionally, Ms. Lantz has advised companies on growth and operational topics as a strategist for Boston Consulting Group and Booz and Company. Ms. Lantz holds three degrees from the University of Michigan, an MBA from the Ross School of Business with a focus on corporate strategy and economics, a master’s in manufacturing engineering and a B.S. in chemical engineering.

4 Mr. Mook has served as Chief Technology Officer since March 2024 and prior to this, served as Chief Engineer since January 2023. Mr. Mook has extensive experience with engineering, new product development, and executive leadership for companies in the aerospace and power generation sector. From 2005 to 2023, Mr. Mook served in multiple engineering positions for General Electric Company and served as an executive starting in 2018. Mr. Mook holds a master’s degree in aerospace engineering from the University of Cincinnati and a bachelor’s degree in Aeronautical and Astronautical Engineering from Purdue University.

5 Mr. Oxholm has served as Chief Legal & Compliance Officer since February 2024 and prior to this, served as Vice President, General Counsel, and Chief Compliance Officer since 2020. Mr. Oxholm has extensive experience with complex business transactions, litigation, and new market entries for companies in the automotive and transportation sectors. From January 2017 to February 2020, Mr. Oxholm served as Vice President, Deputy General Counsel and Chief Compliance Officer for Meritor, Inc. Prior to that, Mr. Oxholm was Senior Vice President, General Counsel and Secretary for LoJack Corporation from 2012 to 2016. Mr. Oxholm holds a J.D. from the University of Pennsylvania and a bachelor’s degree from the University of Michigan.

6 Mr. Ramasamy has served as Chief Commercial Officer at Hyliion since February 2024, bringing extensive expertise in sales, business strategy, product marketing, engineering, project development, execution, and supply chain management within the power generation sector. Prior to joining Hyliion, Mr. Ramasamy spent over 17 years at Cummins Inc. from 2006 to 2024, where he held several senior leadership roles across multiple global markets. Most recently, he served as Executive Director for Global Datacenter Business, leading one of Cummins’ fastest-growing power generation segments. Before that, he held key leadership positions, including Managing Director for Cummins Arabia in the Middle East and General Manager for Power

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Generation in East Asia, overseeing business growth, operational strategy, and market expansion. Before his tenure at Cummins, he held supply chain leadership roles at Kimball International, where he played a critical role in streamlining operations and optimizing supply chain strategies. Mr. Ramasamy holds a B.S. in mechanical engineering from Anna University, India, a M.S. in Industrial & Systems Engineering from Auburn University, and an MBA from Northwestern University, Chicago.

Available Information

Additional information about Hyliion is available at www.hyliion.com. On the Investor Relations page of the website, the public may obtain free copies of our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and any amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 as soon as reasonably practicable following the time that they are filed with, or furnished to, the SEC. References to our website do not constitute incorporation by reference of the information contained in such website, and such information is not part of this Form 10-K.