Lithium battery fires are difficult to fight and according to SCDF statistics, they are on the rise. There are three challenges to overcome, reignition,enclosure and duration.

With these challenges in mind, normal fire extinguishers will not work. A large 9kg powder fire extinguisher lasts at most 14 seconds. It may be able to temporary put out the fire but it will most certainly reignite. 

Almost all fire fighting agents, powder, foam and clean agents will have great difficulty hitting the base of the fire hiding inside the enclosure.

The first option would be the small and powerful Brave Fire Spray Foam type fire extinguisher. With at least a 25 seconds discharge duration, this will be able to put out most small device lithium battery fires. 

The second option would be the fire blanke.t There is no need to expose yourself to the poisonous fumes which is what really kills when there is a fire. The fumes of a lithium battery fire are much more lethal than a normal fire. Hydrogen fluoride in particular will cook your skin and lungs easily and the damage usually takes weeks to recover from.

Fire blankets are so good at suppressing lithium battery fires that SCDF uses them as well.