Nickel-cadmium batteries, often abbreviated as NiCd batteries, are a type of rechargeable battery that uses nickel oxide hydroxide and cadmium as its electrodes. They are known for their ability to deliver high discharge rates and perform well in extreme temperatures. These batteries are commonly used in portable power tools, emergency lighting, and some consumer electronics. One notable characteristic of NiCd batteries is the "memory effect," which can reduce their capacity if they are not fully discharged before recharging. Despite this, they are valued for their durability and long cycle life. However, due to environmental concerns regarding cadmium, their use has declined in favor of other battery technologies like lithium-ion batteries.