About P6
P6 is a founder owned battery engineering company in Zagreb. The founders spent a decade shipping battery systems in automotive before building P6 to bring that discipline to markets that rarely get it. We design and deliver battery packs across the full lifecycle: concept and cell selection, mechanical and electrical design, BMS hardware and software, validation and certification testing, and series production, for customers in drone and UAV, robotics, defence and industrial markets.
The role
You own the mechanical and electromechanical design of battery packs: cell arrangement, structural and enclosure design, busbars and thermal management, from first concept through prototypes and validation to series production in the thousands of units. The role is open from junior to senior: scope, responsibility and the offer follow what you bring. You work closely with the electrical, BMS and manufacturing teams.
What you will do
- Design battery pack mechanics: cell arrangement, structural parts, enclosures, busbars and interfaces.
- Develop thermal management concepts and run first pass sizing calculations: capacity, current, heat dissipation.
- Create 3D models, drawings and release documentation in CAD.
- Support integration of BMS, sensors and wiring harnesses into the pack.
- Build and test prototypes in the workshop; iterate designs to validation readiness.
- Prepare designs for series production: DFM/DFA, supplier engagement, assembly documentation.
- Learn to use Napolitanke as the ultimate colleague bribing mechanism.
What we look for
- Solid fundamentals in mechanics, materials and thermal design; basic electrical understanding. A mechanical engineering or mechatronics background helps.
- Working knowledge of 3DEXPERIENCE (3DX) or Catia.
- Hands on workshop competence with measurement and assembly tools.
- English good enough to defend a design in front of a customer.
Bonus points
- Battery systems, cell-to-pack integration or powertrain background.
- Understanding of Li-ion cell behavior and thermal fundamentals.
- Structural or thermal simulation experience (FEA, CFD).
- Python or MATLAB for engineering data processing.
- Formula Student or similar hands-on project background (accumulator, solar car, rover, drone).
What we offer
- Gross annual salary: EUR 26,000 to 55,000, depending on experience.
- 25+ days of annual leave.
- On site at our Buzin workshop and lab: the packs you design are built a few meters from your desk.
- Full design ownership from concept to delivered pack, on international programs across drone and UAV, robotics and industrial markets.
- No corporate perks yet: no gym membership, no fruit basket, no branded hoodie. That budget goes into lab equipment and the salary range above. There is coffee, and sometimes there is burek for birthdays.
How to apply
Send us your CV and the thing you have done that you are proudest of to kadrovska@p6.hr, subject “Battery Engineer, Mechanical Design”. Applications in English or Croatian. We look forward to your application, even if you do not meet every requirement.