Why must you let the device cool for 15 minutes before putting it in the lithium ion containment bag?

Letting the device cool for 15 minutes before placing it in the lithium ion containment bag is essential primarily to avoid further ignition. Lithium-ion batteries can become volatile and pose a fire risk when they are overheated. By allowing the device to cool, you decrease the likelihood of any residual heat causing potential combustion or ignition within the containment bag. This safety procedure is critical, as the containment bag is designed to manage specific incidents related to lithium-ion battery failures, and introducing a hot device could compromise its effectiveness and safety.

While considerations such as battery damage, safe storage, and weight might also be relevant in other contexts, they do not directly address the immediate safety concern posed by temperature when the device is secured in a containment bag. Recognizing and mitigating fire risks is key when handling devices with lithium-ion batteries, making the requirement to cool the device beforehand a vital protocol.