High-Current Solenoid Driver Circuit Design

I need a safe, reliable design for a high-current driver circuit to power a 12V solenoid using 18V tool batteries (Ryobi/Milwaukee/Makita).

Requirements:
- Deliver a strong over-voltage “kick” (18V for ~100–300 ms)
- Automatically drop to safe holding current using PWM or similar
- Include timing control
- Coil protection: Flyback/TVS, overcurrent, thermal
- More reliable than a generic timer relay setup

Deliverables:
- Schematic
- BOM (Bill of Materials)
- PCB design

Ideal Skills and Experience:
- Expertise in circuit design
- Experience with high-current applications
- Familiarity with PWM and over-voltage protection circuits
- PCB design experience