NiMH and NiCd Batteries

Handling NiMH Batteries During Fires

In the event there is a fire where nickel-metal hydride (NiMH) batteries are present, apply a smothering agent such as METL-X, sand, dry ground dolomite, or soda ash. The area can also be flooded with water. A smothering agent will extinguish burning nickel-metal hydride batteries. Water may not extinguish burning batteries but will cool the adjacent batteries and control the spread of fire. Burning batteries will burn themselves out (different wording). Virtually all fires involving NiMH batteries can be controlled with water. However, when water is used hydrogen gas may be produced. In a confined space, hydrogen gas can form an explosive mixture, therefore smothering agents are recommended.

Firefighters should wear a self-contained breathing apparatus (specify PPE class). Burning nickel-metal hydride batteries can produce toxic fumes including oxides of nickel, cobalt, aluminum, manganese, lanthanum, cerium, neodymium, and praseodymium. All fires should be handled by professionals who are trained to fight fires. 

Storage of NiMH Batteries

NiMH batteries should be stored in cool, well-ventilated areas. The NiMH battery terminals need to be taped with a nonconductive material so that the terminals do not contact other battery terminals. Here are some examples:

•           Electrical tape

•           Packing tape

•           Duct tape

* If batteries are going to be sent to a recycler, try not to cover the entire battery so that sorters can determine the type.

Handling and Storage NiCd

Nickel Cadmium (NiCd) battery cells are filled with electrolytes and always need to be handled, stored, and transported with vents facing upwards. Avoid placing NiCd batteries in direct sunlight, high temperature, and high humidity. These batteries should be stored in a cool and dry place, between 10° to 30°C (50° to 86°F) and with a humidity of 45% to 85%. Do not connect a positive terminal to a negative terminal with electrically conductive materials. Store and operate the Nickel-Cadmium batteries in separate rooms where the lead-acid batteries are stored and operated. Keep NiCd batteries away from water in cool well-ventilated areas. Do not store any other material on top of the batteries.

Just like NiMH batteries, NiCd batteries need the terminals taped with nonconductive materials so that the terminals do not contact other battery terminals. Nonconductive material examples:

•           Electrical tape

•           Packing tape

•           Duct tape

* If batteries are going to be sent to a recycler, try not to cover the entire battery so that sorters can determine the type.