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%ma 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.

Do you want to contribute to a more sustainable world? Are you excited to help shape the future of battery technology and consequently the future of consumer electronics and mobility? Can you not wait to dive into a VC-backed deep tech scale-up with the ambition to change the world?

We are looking for an enthusiastic B2B Product Marketing Internship to join our innovative and ambitious organization.

You are eager to learn and excited to work with us to make better batteries. You will work close together with technicians, battery engineers, production process engineers and other departments . You will report to Business Developer. You will be part of a young, international, ambitious and diverse team that is determined to make a better world with cleaner energy.

It is a full-time position. You will mainly be working in Leiden, and may occasionally work in Eindhoven.

You will be responsible for:

• Conduct market research to identify trends, competitive landscape, and customer needs in the battery industry.
• Analyze data to provide insights for product development and marketing strategies.
• Assist in the development of new battery products by collaborating with cross-functional teams including engineering, manufacturing, and sales. Provide input on product features, specifications, and pricing based on market research and customer feedback.
• Support the creation and execution of marketing campaigns to promote our battery products. This includes content creation for social media, website, and marketing materials
• Assist in managing digital marketing channels such as email marketing, advertising, and social media ads
• Engage with customers through various channels to gather feedback, address inquiries, and build relationships.
• If necessary, we may require you to perform activities normally undertaken by others or to take on additional activities.