Laboratory Technician (battery R&D) Leiden

About LeydenJar

At LeydenJar Technologies, we’re on a mission to redefine the future of energy storage. Our goal is to become the world’s innovation leader in advanced battery anodes, empowering the next generation of batteries that drive progress.

Why does this matter? Because the world needs higher energy density batteries not just for better consumer electronics, but for electric vehicles, e-flight, and beyond. While the battery industry typically advances by only 3% per year, our breakthrough pure silicon anode technology delivers an improvement of up to 70%, a true game changer. Often called the “holy grail” of the battery industry, our technology unlocks new possibilities for electrification, sustainability, and resilience in global supply chains.

What we do:

• We produce pure silicon anode rolls that fit seamlessly into existing battery cell manufacturing lines, enabling customers to make a quantum leap in performance or create entirely new product categories.

• Our initial focus is on consumer electronics, with automotive applications already in development.

• By leveraging semiconductor thin-film technology (plasma deposition) and scaling it to battery anodes, we’ve overcome the long-standing challenges of silicon in batteries, delivering durability and efficiency at scale.

To meet global demand, we’re scaling up:

• PlantOne in Eindhoven opens in 2026, producing anode rolls and validating our roll-to-roll production tools.

• PlantTwo, our large-scale production facility, will follow, establishing LeydenJar as a key player in the global battery market.

This is an enormous opportunity and an ambitious journey. It requires bold, creative, and diverse minds who share our passion for innovation and sustainability. At LeydenJar, we value different perspectives, inclusive collaboration, and gender equality because we know that diversity fuels breakthrough ideas.

We are seeking a dedicated Laboratory Technician to support our pre-pilot battery cell manufacturing operations. If you enjoy hands-on work with cutting-edge equipment and take pride in precision and efficiency, this role is for you. You will become part of a young, international, and ambitious team driven to make a real impact toward a more sustainable future powered by clean energy.

What will be your responsibilities?

You will be responsible for:

• Production of battery cells in the lab; 

• Logging/processing data from the production builds;

• Executing tests of battery cells using electrical equipment;

• Working according to lab planning and carrying out tasks to remain on schedule;

• Maintenance of assigned machinery;

• Ensuring that the lab is a clean and safe environment, by adhering to all Health, Safety and Security guidelines and procedures;

• Stock-taking and ordering materials;

• Continuous improvement of procedures and safety in the lab.

What we expect from you:

• You are detailed and thorough;

• You like being hands-on and don’t enjoy sitting behind a desk all day;

• You have a positive attitude and are full of energy. You are a driving part of our Lab in Leiden, and you want to make it run even better and safer;

• You carry out plans as agreed, but you are flexible to change as required

• Applied science/College (MBO/HBO) degree in a technical discipline;

• Good communication skills in English;

• Experience in a chemical / mechanical and / or electrical lab is a plus;

• Experience with some coding (Python) is a plus;

• Experience with HSE implementation in a lab/workshop environment;

• Capability of CAD drawing is a plus;

• Good skills in MS Excel / Word / PowerPoint, and fine with learning new IT apps;

• Must be an EU citizen (so you can freely work in The Netherlands) or be in possession of a valid residence permit to work in The Netherlands.

Why LeydenJar?

• Unleash Your Potential: Step into a workplace where growth and ownership go hand in hand. We empower every individual regardless of background, gender, or identity to thrive and achieve their career aspirations.

• Pension & Insurance Security: We care about your future. LeydenJar contributes 10% on top of your monthly gross salary toward your pension and life insurance, ensuring long-term security for you and your loved ones.

• Recharge & Refresh: Enjoy 25 vacation days per year (based on full-time hours) because work-life balance is essential for everyone.

• Travel Made Easy: We cover your home-to-work travel costs with €0.23 per kilometer or provide an NS Business Card for hassle-free public transportation.

• Continuous Learning: Access our online learning platform (Udemy) to develop your skills and unlock new opportunities for personal and professional growth.

• Diverse, Inclusive & Equal: Be part of an international team of 20+ nationalities, where everyone’s voice matters, and where diversity, equity, and inclusion are more than values they’re actions.

• Community & Connection: From team-building events and monthly lunches to year-end celebrations and inclusive gatherings, we create spaces where everyone feels welcome and engaged.

Are you ready to take on the challenge as a Laboratory Technician?

We are looking forward to your application!

If you'd like to learn more about LeydenJar's amazing team, see below:

At LeydenJar we value diversity, and we provide equal opportunities to all applicants without regard to race, color, ethnicity, religion, gender, pregnancy/childbirth, age, national origin, sexual orientation, disability, etc. If there are two or more applicants of equal suitability for a certain position, LeydenJar can under circumstances decide to select applicants based on positive discrimination in full compliance with all relevant and applicable law.