What action is recommended for overheated batteries that have not ruptured?

In the context of handling overheated batteries that have not ruptured, spraying them with water fog is recommended due to its effectiveness in cooling the batteries and reducing the risk of thermal runaway. Water fog helps dissipate heat without directly introducing large amounts of water, which could potentially cause other complications, such as a short circuit or chemical reactions, especially in the case of certain battery chemistries.

Using water fog allows for a controlled cooling process, minimizing the likelihood of damage to the battery while effectively lowering its temperature. This method of cooling is particularly useful because it addresses the immediate danger of heat buildup while avoiding further hazards associated with pouring water directly onto the batteries.

The other options, while they may seem reasonable at first glance, do not provide the same level of safety or efficiency in cooling overheated batteries. Allowing the batteries to cool on their own might be too slow and could allow the situation to escalate. Smothering them with an absorbent does not directly address the source of heat, and placing batteries in a bucket of water could lead to a dangerous reaction or compromise the integrity of the battery if it were to rupture.