---
title: 'Senior / Staff Welding & Sealing Equipment Engineer at Factorial Energy'
canonical: 'https://feeny.ai/job/senior-staff-welding-sealing-equipment-engineer-factorial-energy-cheonan-south-ecq3jsz6wn03'
type: 'job'
last_seen: '2026-09-09'
---

# Senior / Staff Welding & Sealing Equipment Engineer at Factorial Energy

- **Company:** Factorial Energy
- **Location:** Cheonan South, South Korea
- **Posted:** 2026-08-04
- **Last confirmed live:** 2026-09-09
- **Apply:** https://job-boards.greenhouse.io/factorialenergy/jobs/6133097004

## Job description

## Who We Are

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 Welding & Sealing Equipment Engineer to join our Cheonan, South Korea site. This person will own the full-cycle development, commissioning, customization, optimization, and mass production scaling of automatic welding and sealing equipment for our Silicon Power Cell pouch cell line. This person will lead welding & sealing equipment R&D, prototype debugging, pilot verification, and mass production iteration; deliver equipment technical upgrades, OEE and yield improvements, and build standardized equipment management systems.

In this role, you will:

- Lead full-lifecycle development, commissioning, and mass-production validation of automatic welding and sealing equipment, iterate core process parameters, and complete equipment adaptation for new product launch.
- Conduct equipment review, FAT/SAT acceptance and IQ/OQ/PQ qualification, and unify precision and quality control standards for welding and sealing processes.
- Upgrade and retrofit mass-production welding and sealing equipment to improve OEE, production yield and line capacity, and reduce manufacturing costs.
- Optimize welding fixtures, sealing structures and core process parameters to stabilize production, eliminate welding spatter, virtual welding, seal leakage and wrinkling issues, and support rapid multi-spec pouch cell changeover.
- Build complete standardized equipment management systems for welding and sealing stations, including SOPs, maintenance schedules, calibration specifications, PFMEA, control plans, and equipment failure databases.
- Collaborate with cross-functional teams (R&D, Process, Quality, Manufacturing, Maintenance) and external vendors to advance new line startup, equipment development and technical renovation projects.
- Optimize laser welding energy control, servo positioning logic, and sealing pressure/temperature closed-loop parameters to adapt silicon anode cell characteristics and eliminate assembly defects.
- Lead equipment technical transfer from lab/pilot EVT/DVT/PVT to mass production, identify equipment bottlenecks and drive sustained yield improvement.
- Adopt 8D, DOE, SPC, and root-cause analysis to resolve typical welding and sealing abnormalities, drive cross-functional troubleshooting, and close CAPA for recurrent equipment 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 welding & sealing equipment development, retrofit and production ramp-up.
- 2+ years of professional experience in laser welding and thermal sealing equipment structure and control logic; skilled in welding energy tuning, track precision control, temperature/pressure parameter calibration and sealing uniformity optimization.
- Capable of mechanical/electrical drawing reading and CAD/SolidWorks fixture design; familiar with laser control system, servo motion, constant temperature-pressure control and precision automation systems.
- Proficient in DOE, PFMEA, Control Plan, 8D and root cause analysis; independent in equipment troubleshooting and technical optimization.
- Experienced in pouch cell welding & sealing line NPI and mass production ramp-up projects.
- Equipped with cross-functional coordination, project management and overseas vendor communication abilities; competent in on-site troubleshooting and English technical documentation.
- Proficient in English for technical document reading, global technical 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 (recruitment@factorialenergy.com)

## About Factorial Energy

## Company Overview
- **One-liner**: Factorial Energy is a U.S. developer of high‑performance solid‑state battery technology for eMobility, defense, robotics, and hyperscale data centers.
- **Entity Type**: Public (Nasdaq: FAC)
- **Headquarters**: Billerica, Massachusetts, USA
- **Founded**: 2013 (spun out of a heritage company founded from Cornell University)
- **Founders**: Siyu Huang (Ph.D/MBA, CEO) and Alex Yu (Ph.D, CTO)

## Core Business
- **Primary industry**: Battery technology / Energy storage (solid‑state lithium‑metal batteries)
- **Target customers**: B2B – automotive OEMs, defense & aerospace contractors, robotics manufacturers, hyperscale data‑center operators
- **Mission**: “We purposefully pursue milestones to scale a high‑performing product that brings us closer to a greener future.” The company states it is “all charged up to save the planet, empower people, and advance our industry.”

## Products & Services
- **FEST® (Factorial Electrolyte System Technology)** – Proprietary solid‑state electrolyte platform. The company has delivered 40 Ah and 106 Ah automotive‑grade B‑samples to global OEMs and demonstrated a 100+ Ah cell at CES.
- **Solstice™** – Multi‑layer solid‑state battery platform (next‑generation architecture) designed for drones, robotics, and automotive applications.
- **Manufacturing Technology** – 80 % drop‑in compatible with existing lithium‑ion production lines; proprietary dry‑coating process to enhance efficiency and reduce cost.

## Market Standing
- **Valuation/Market Cap**: ~$1.3 billion equity value (as of June 2026 IPO via SPAC with Cartesian Growth Corporation III)
- **Key Metric**: Gross proceeds of more than $100 million from the SPAC transaction (revenue not yet publicly disclosed as the company just entered public markets)
- **Notable Investors/Partners**: In‑Q‑Tel (strategic investor for U.S. national security), Mercedes‑Benz, Stellantis, Hyundai Motor Company, Kia Corporation; board includes former Daimler CEO Dieter Zetsche and former Stellantis CTO Michael Bly
- **Growth Signals**: Completed Nasdaq listing in June 2026; real‑world road testing with Mercedes‑Benz achieved over 1,200 km range on a single charge; expanded into defense, aerospace, and hyperscale data‑center segments; 150+ patents and patent applications

## Competitive Advantages
- **Capital‑light model**: Joint manufacturing partnerships allow rapid, scalable deployment without massive factory investment.
- **Drop‑in compatibility**: 80 % compatible with existing lithium‑ion production lines, lowering adoption barriers for partners.
- **Proprietary dry‑coating process**: Reduces cost and energy use while improving performance.
- **Strong IP portfolio**: Broad patent estate covering electrolyte, cell design, and manufacturing processes.

## Strategic Focus
- **Scale to volume**: Progress toward the first U.S. solid‑state production program for passenger vehicles.
- **Market diversification**: Penetrate defense, aerospace, robotics, and data‑center energy storage beyond automotive.
- **Sustainability**: Achieve carbon neutrality by mid‑2030; develop end‑of‑life recycling (partnered with Young Poong for lithium‑metal recycling); sustainable and regionalized supply chain.

## Why Work Here
- **Culture & values**: “SMAHRT” – Safety, Meritocracy, Agility, Humility, Respect, Transparency. Collaborative environment where engineers and business experts work side‑by‑side on bold ideas.
- **Diversity & inclusion**: Female‑led company (CEO Siyu Huang); >70 % of employees from racial and ethnic minorities (as of July 2023). Explicit DEI statement and commitment to diverse perspectives.
- **Benefits**: Competitive wages; medical, dental, and vision insurance; HSA/HRA/DCRA programs; 401K with company match; flexible PTO; short‑ and long‑term disability; continuing education support; family leave.
- **Work environment**: On‑site at Billerica (MA) headquarters for manufacturing and R&D roles; also has sales/supply chain offices in Germany, Korea, and Japan. Likely on‑site for technical roles; hybrid may be possible for non‑lab positions.
- **Impact**: Work on battery technology that touches automotive, defense, robotics, and critical energy infrastructure – with a clear mission toward a greener future.

## Sources
1. [Factorial Energy – Company Website](https://factorialenergy.com/)
2. [Factorial Energy – Careers Page](https://factorialenergy.com/careers/)
3. [Factorial Energy – About Us](https://factorialenergy.com/about/)
4. [Factorial Energy – Investor Relations FAQs](https://ir.factorialenergy.com/ir-resources/investor-faqs)
5. [Factorial Energy – Nasdaq Listing Press Release](https://ir.factorialenergy.com/news-releases/news-release-details/factorial-lists-nasdaq-bringing-solid-state-batteries-validation)

## Other roles at Factorial Energy

- [Inventory Manager - Battery Mass Production](https://feeny.ai/job/inventory-manager-battery-mass-production-factorial-energy-cheonan-south-xkeywtk4n4an) — Cheonan South, South Korea
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