Battery fans are portable cooling devices powered by batteries, making them convenient for use in various settings, such as homes, offices, or outdoor activities. They come in different sizes and designs, often featuring adjustable speeds and oscillation to enhance airflow. These fans are especially useful during power outages or in areas without electrical outlets. Many battery fans are lightweight and easy to carry, making them ideal for camping trips or picnics. Some models even include additional features like built-in lights or USB charging ports for added functionality.