What does corrosion on battery terminals cause?

• A. Higher voltage stability
• B. Longer battery life
• C. Poor electrical connection
• D. Increased charging rate

Answer: (C)

Corrosion on battery terminals causes a poor electrical connection. The corrosion forms a crust that insulates and reduces the contact area between the terminal clamp and the metal, increasing resistance at the connection. With higher resistance, the battery can’t deliver or receive current reliably, leading to symptoms like slow engine cranking, dim lights, or charging problems. The charging system may work harder to push current through the bad connection, and heat from this struggle can make the corrosion worse. Cleaning the terminals, tightening the clamps, and using a protective grease restores solid metal-to-metal contact and improves current flow. This issue doesn’t improve voltage stability or battery life, and it doesn’t correctly increase the charging rate; it typically degrades electrical performance.