Why are batteries environmentally hazardous?
Because lithium batteries contain metal that will spontaneously ignite if exposed to air. Also, the negative and positive poles on some lithium batteries are close together, leading more easily to short circuit which can cause fire.
Explain the issue of safety versus cost.
The issue of safety here is that if the lithium batteries are improperly package, damage or have manufacturing defects, they can short circuit and ignite. Overheated lithium batteries can blow the lids off steel shipping containers and damage a plane. Once a battery catches fire, the heat can set off other batteries. Obama administration proposed rules but they are opposed by many because they say the rules would cost them hundreds of millions of dollars in added packaging, paperwork and training for employees. It will also mean delays in getting medical equipment to patients and would drive up the cost of shipments.