Rechargeable batteries are used in thousands of applications ranging from cordless power tools, mobile phones and laptop computers, to hybrid electric vehicles, railroad signaling systems and aerospace applications.
Nickel is used in three main types of rechargeable batteries: nickel cadmium (NiCd), nickel metal hydride (NiMH), and lithium ion (Li-ion). By weight, NiCd batteries contain 10-25% nickel, NiMH batteries contain 30-45% nickel, and Li-ion batteries contain up to 5% nickel.
This advisory note seeks to provide advice to manufacturers and consumers on recycling nickel-containing rechargeable batteries.
The value of recycling nickel
Rechargeable batteries keep wireless products going for hundreds of charges. When these batteries eventually reach a point when they can no longer be recharged – its "end-of-life" – it is important to recycle them. Recycling batteries returns important materials, including nickel, to use and reduces the demand for new mined materials. In addition, recovering metals through recycling requires less energy than that needed to produce new metals from ores. Lastly, recycling spent batteries reduces the risk of emissions of metals to air, soil and water.
How batteries are recycled
The nickel and cobalt that are recovered from NiMH or Li-ion batteries are often used in the manufacturing of new NiMH or Li-ion batteries. This is an example of closed-loop recycling, as shown in Figure 1.
NiMH batteries can also be recycled with NiCd batteries. In this process, the nickel is recovered in the form of ferronickel, which is then used as a raw material to make stainless steel. The stainless steel, at end-of-life, can in turn be recycled indefinitely into new stainless steel.