Copper vs Aluminum Conductors

Copper dominates WPT windings for its conductivity and mature Litz supply chain. Aluminum appears where mass reduction matters — airborne or mobile robot payloads — at the cost of larger cross-section for same Rdc and more careful termination against galvanic corrosion and creep.

At AC frequencies, material choice still follows skin and proximity rules; aluminum's lower conductivity means either thicker sections or accepting higher loss for the same geometry.

01Copper advantages

• Higher conductivity — smaller coil for same loss.
• Reliable solder, weld, and crimp terminations.
• Wide Litz and foil vendor base.

02Aluminum considerations

Use plated pads, ultrasonic weld, or mechanical clamps rated for thermal cycle. Avoid direct copper-aluminum contact without isolation in wet environments. Verify Rac on prototype — some aluminum foil designs win on weight but need larger area changing k.

03Decision frame

• Default copper unless mass budget forces aluminum.
• Re-run thermal and k models on any material swap.
• Fleet maintenance training for aluminum termination inspection differs from copper.