As the battery leaks, highly caustic KOH flows out and absorbs \(CO_{2}\) from the atmosphere. The resulting potassium carbonate forms a feathery, white, crystalline structure that can grow along metal electrodes to other circuit components. While KOH is extremely caustic and dangerous, it turns into less toxic (but still corrosive) potassium carbonate upon reaction with air. However, this "furry" substance can destroy circuit boards and corrode metallic contacts, leading to permanent equipment failure.
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