Data Scientist

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 energetic Data Scientist to join our innovative and ambitious organization.

About LeydenJar

LeydenJar is a high-tech company, developing pure silicon anodes for a lithium-ion battery that will change the world. We are proud that, here at LeydenJar, we:

• boost Li-ion battery energy density by 70% by using 10x thinner anodes
• improved cycle life to >450
• achieved fast charging to 60% in under 10 min!

We are currently still in an R&D phase, but we are ready to start the actual production of anode foil. LeydenJar Plant One will open in 2026.

Your mission
LeydenJar has the goal to develop machine learning driven manufacturing and R&D capabilities. As a key driver of this goal, you will analyze and build models of industrial production data and share your insights across the organization. One of your key achievements will be to identify meaningful signals from sensors on our production machines and connect them to machine behavior and product outcome. Beyond correlational analysis, you will contribute to inverse design models for AI-driven production recommendations to help launch LeydenJar's product to new heights. You will work from our production facility in Eindhoven and report to the Senior Data Scientist as part of the Silicon R&D department. Your skills will complement the growing group of data professionals at LeydenJar which include data system architect and IT application engineer roles.

About the job

The foundations of data collection and usage have been set at LeydenJar with key datasets stored in Azure, data reports in PowerBI, and foundational models and exploratory analysis developed in Python. However, there are still many unexplored areas in which you will play a key role. Your responsibilities will include:

• Researching, building, and deploying machine learning models to enable data-driven control of the production process to optimize product quality and yield. Your models will also enable AI-driven recommendations for new process parameters or material properties through the use of techniques such as Genetic Algorithms or Bayesian Optimization. Model inputs will include material characterization measurements, production outcomes, and machine sensor timeseries.
• Serving as the go-to data scientist in the production facility, ready to support your colleagues on their analysis goals and questions. As such you will need to understand and track data sources and assist on adhoc data exploration requests.
• Collaborating with the IT and Industrialization Teams to define data system requirements and architecture for data sources and pipelines.
  
• Learning from field experts in plasma and production to translate scientific understanding into machine learning model improvements.
  

About you

• You have an MSc or higher in a technology-related field, with a preference for data-focused degrees. A BSc with 3+ years of machine learning experience will also be considered. We have a preference for candidates who have previously worked in a data analyst or data scientist role analyzing real-world data in a professional setting.
  
• You can code in Python and SQL. In Python you have experience with data analysis libraries such as pandas, matplotlib, scikit-learn, tensorflow, scipy, or statsmodels.
• You understand the fundamentals of machine learning such as model performance metrics, sampling, cross-validation, algorithm tradeoffs, and explainability. You have a passion for the field and are excited to make real-world impact.
  
• You are familiar with cloud environments such as GCP, AWS, Azure or Snowflake.
  
• You are familiar with or keen to learn best practices for code and model development such as version control and CI/CD.
• You are a confident presenter eager to share important findings with the broader team and have the ability to adjust your explanation to your audience.
• You are a team-player who likes to learn from others and will volunteer their time to help colleagues achieve their objectives.
• You are comfortable working in a fast-moving environment and thrive from taking on new challenges.
  
• You are fluent in English.

What can you expect from us?

• Support and autonomy from a management team eager to realize the potential of AI/ML
• Unique experience in a rapidly scaling VC-backed start-up environment
• High degree of autonomy and a chance to work on potentially world-changing technology that can be a game changer to a range of industries and a key enabler for the energy transition
• A total of 10% (on top and based on your monthly gross salary) will be paid by LeydenJar for pension and other insurances)
• You get 25 days of vacation per year (based on 40 hours working week)
• NS Business Card or reimbursement of 0.21 euro per km for commuting
• Access to OpenUp mental health platform
• Regular progress talks and support to reach your career goals
• Great colleagues; at LeydenJar you will be part of a multi-national, ambitious, innovative and entrepreneurial team/20+ different nationalities!/
• Thirsty Thursday – we have drinks every first Thursday of the month
• We host internal FUN events each year and offer personal development perks.
• We have fresh fruit delivered every Monday in both locations /Leiden and Eindhoven/

Do you want to take on the challenge as Data Scientist?

We are looking forward to your application!

If you'd like to learn more about LeydenJar 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.