Factorial Energy

Senior / Staff Cell Stacking Equipment Engineer

Join Factorial Energy in Cheonan as a Senior Cell Stacking Equipment Engineer. Lead development and optimization of automatic stacking equipment for solid-state battery production. Benefit from working with cutting-edge technology in a global leader company and enjoy a collaborative, innovative environment.
Factorial Energy
Factorial Energy
Cheonan, South Korea On-site Full time UTC+09:00

Factorial Energy

Company Overview

Name

Factorial Energy

Headquarters

Woburn, Massachusetts, United States

Founded

2013

Size

Approximately 150 employees (source: linkedin.com). Factorial has raised over $65 million and achieved a $1 billion valuation (source: batteryburnbook.com).

What They Do

Factorial Energy specializes in the development of solid-state batteries, which are pivotal for various applications including electric mobility, defense, AI/robotics, aviation, power tools, marine vehicles, consumer electronics, and energy storage systems. Their technology emphasizes high energy density, achieving 350-450 Wh/kg compared to the 200-300 Wh/kg typical of current electric vehicle (EV) cells. Additionally, Factorial's batteries are designed for enhanced safety, fast charging capabilities, and a wide operational temperature range from -30°C to 45°C (source: factorialenergy.com).

The core of their innovation lies in the Factorial Electrolyte System Technology (FEST®), which utilizes a quasi-solid polymer electrolyte combined with an ultrathin lithium-metal anode and a high-capacity cathode. This technology allows for approximately 80% compatibility with existing lithium-ion production lines, facilitating scalability and integration into current manufacturing processes (source: factorialenergy.com).

Complementary technologies such as Solstice™, a sulfide-based all-solid-state electrolyte, and Gammatron™, an AI-driven battery digital twin software, further enhance their offerings. Solstice™ boasts high thermal stability and zero liquid content, while Gammatron™ accelerates R&D in electrolyte development and battery management systems (source: enertherm-engineering.com).

Projects & Track Record

Factorial Energy has achieved significant milestones in battery development, including a series of prototypes that have progressively increased in capacity and complexity. Notable achievements include the validation of 0.6 Ah Li-metal chemistry in 2017, the introduction of a 40 Ah 30-layer graphite anode prototype in 2021, and the unveiling of a 106 Ah automotive B-sample cell at CES 2023. These advancements demonstrate Factorial's commitment to pushing the boundaries of solid-state battery technology (source: factorialenergy.com).

Recent Developments

In October 2023, Factorial Energy inaugurated its $50 million manufacturing facility in Methuen, Massachusetts, which is set to be the largest solid-state battery production line in the U.S. with a capacity of 200 MWh. This facility is expected to significantly enhance their production capabilities and support the scaling of automotive applications (source: waveep.com).

In 2024, the company shipped 106 Ah B-samples to various OEMs and unveiled their Solstice™ technology after a period of stealth development. Additionally, they have been recognized as a leading player in the deep tech sector, ranking #25 among the Top 100 Private Deep Tech Companies (source: factorialenergy.com).

Working There

Factorial Energy is actively hiring across various departments including R&D, manufacturing, sales, and engineering, particularly in response to their recent expansion efforts. The Methuen facility is expected to create over 150 jobs, contributing to the local economy while supporting the company's growth in solid-state battery production. The company culture emphasizes speed and innovation, with a focus on ethical governance and sustainability goals, including a commitment to carbon-neutral production by mid-2030 (source: factorialenergy.com).


Last updated on Feb 23, 2026 | Report an issue

Factorial Energy is a pioneering U.S.-based solid-state battery company driving the future of energy storage and electrification. Partnered with global leaders including Mercedes-Benz, Stellantis, Hyundai, and Kia, Factorial is at the forefront of developing next-generation e-mobility platforms for commercial, defense, and consumer applications-spanning electric vehicles (EVs), drones, eVTOL aircraft, power tools, marine systems, robotics, and more. The company has achieved multiple industry firsts, including being the first to power a demonstration vehicle with a global OEM (Mercedes- Benz) which achieved over 1,200 km (749 mi) of range, and the first to earn UN 38.3 certification for automotive-sized lithium-metal solid-state cells, the first to deliver B-samples of automotive-sized solid-state batteries to major OEMs.

The Opportunity

Factorial Energy is seeking a Senior / Staff Cell Stacking Equipment Engineer to join our team in our Cheonan, South Korea, location. This person will be responsible for owning the full-cycle development, commissioning, customization, optimization, and mass production scaling of automatic stacking equipment for our Silicon Power Cell pouch cell line. The Ideal candidate will lead new stacking process equipment R&D, prototype debugging, pilot verification, and mass production iteration; deliver equipment technical upgrades, OEE & yield improvement; and build a standardized equipment management system.

In this role, you will

  • Lead full-lifecycle development, commissioning, and mass-production validation of automatic stacking equipment, iterate process parameters, and complete equipment adaptation for new product launch.
  • Conduct equipment review, FAT/SAT acceptance and IQ/OQ/PQ qualification, and unify precision control standards for stacking equipment.
  • Upgrade and retrofit mass-production stacking machines to improve OEE, yield and line capacity, and reduce production costs.
  • Optimize stacking fixtures, protection structures and process parameters to stabilize production, improve cell consistency and support rapid multi-spec product changeover.
  • Collaborate with cross-functional teams and external vendors to promote new line startup, equipment development and technical renovation.
  • Optimize stacking machine structure, tension control, CCD positioning and compaction logic to adapt silicon anode expansion, eliminate stacking misalignment, separator wrinkles and other key defects.
  • Lead equipment technical transfer from lab/pilot EVT/DVT/PVT to mass production, identify production bottlenecks and drive sustained yield improvement.
  • Adopt 8D, DOE, SPC, and root-cause analysis to resolve typical stacking defects, drive cross-functional troubleshooting, and close CAPA for recurrent failures.

We are looking for people who

  • Bachelor's degree or above in mechanical, mechatronics, electrical automation, materials, chemical engineering, or related fields.
  • 3+ years of experience in pouch cell stacking equipment development, retrofit, and production ramp-up.
  • 2+ years of professional experience in stacking machine structure and control logic; skilled in precision, tension, thermal pressing, CCD positioning, and compaction parameter tuning.
  • Capable of mechanical/electrical drawing reading and CAD/SolidWorks fixture design; familiar with servo control, tension system, CCD vision and temperature-pressure closed-loop systems.
  • Proficient in DOE, PFMEA, Control Plan, 8D and root cause analysis; independent in equipment troubleshooting and technical optimization.
  • Experienced in pouch cell stacking line NPI and mass production ramp-up projects.
  • Equipped with cross-functional coordination, project management, and vendor communication abilities; competent in on-site troubleshooting and English technical documentation.
  • Proficient in English for technical document reading, global meetings, and technical report delivery.

Work Location

Cheonan, South Korea

Factorial Energy is an equal opportunity employer that values diversity at all levels. All qualified applicants, regardless of personal characteristics, are encouraged to apply.

To request a reasonable accommodation to complete an application, job interview, and/or to otherwise participate in the hiring process, please contact ([email protected])

Apply now

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About the role

August 11, 2026

August 11, 2026

Full time

On-site

Company

Energy Storage, EV Charging Infrastructure

Factorial Energy

factorialenergy.com

  •  Cheonan, South Korea

3+ years in pouch cell stacking equipment development

UTC+09:00