Mechanical Engineer
Spear Power Systems LLC
Grandview, MO

Mechanical Design Engineer (I or II)

Spear Power Systems LLC manufactures advanced lithium ion batteries for defense, marine, mining, and renewable energy applications. We deliver value to our customers by designing, manufacturing and integrating high power, high voltage battery systems deployed in challenging environments. Our team members are creative, enthusiastic and entrepreneurial partners in our success.

Spear is seeking an energetic, independent team member to design custom lithium ion battery energy storage systems ranging in scale from shoe boxes to shipping containers. The successful candidate will be responsible for designing the structures, thermal controls and electrical connections that bottle tremendous amounts of chemical energy in a tiny package and then releases it as controlled bursts of electricity. The Mechanical Engineer’s designs will power passenger ferries of the future and help defend against attacking drones. Spear values innovative research experience, inquisitiveness, leadership and accountability.


  • Define battery system requirements and derive mechanical requirements
  • Design battery systems including the structure, electrical interfaces, and thermal subsystem
  • Model and empirically verify the thermal behavior of battery systems
  • Conduct analytical or finite element analysis of the behavior of battery systems under various shock, vibration, and constant mechanical loads
  • Support failure modes effects analysis and safety hazard analysis
  • Work with vendors including plastics modeling, machining, sheet metal forming, stamping, welding, extrusion, casting, and 3D printing to ensure delivery of high quality, low cost parts
  • Support manufacturing & quality engineering to develop assembly and test processes


  • The role is envisioned for a candidate with 3 to 10 years of experience. Exceptional recent graduates will be considered. The levels of responsibility assigned will be adjusted based on applicant’s background.
  • Excellent ability to adapt and learn quickly.
  • Excellent initiative, time management, and organizational skills.
  • Strong interpersonal skills for working with external and internal teams.
  • Strong oral and written communications skills.
  • Familiarity with SolidWorks or similar mechanical design tools preferred.
  • Familiarity with Matlab/Simulink or similar modeling tools preferred.
  • Familiarity with finite element analysis preferred.
  • Bachelor’s or master’s degree in mechanical engineering preferred. Bachelor’s or master’s degree in electrical engineering, physics, or chemistry required.Location – this position is located Spear’s office in the Kansas City areaSpear offers challenging work, an excellent work environment and great benefitsPlease, no phone calls, agencies or recruiters.Spear is an Equal Opportunity/Affirmative Action Employer and embraces diversity in our employee population. It is the policy of Spear to provide equal opportunity to all qualified applicants and employees without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, protected veteran status, or genetic information. Spear will refrain from discharging, or otherwise discriminating against, employees or applicants who inquire about, discuss, or disclose their compensation or the compensation of other employees or applicants.

U.S. Citizenship or Legal Permanent Residence required to support government projects.

Job Type: Full-time


  • Bachelor's (Required)