Definition
A type of rechargeable battery that uses nickel and cadmium as the active chemical materials in its cells. In turboprop and turbine aircraft, NiCad batteries are commonly used for engine starting and as a backup electrical power source because they can deliver very high current for short periods and operate reliably across a wide temperature range.
Plain English
A heavy-duty rechargeable battery built from nickel and cadmium. It can dump out a lot of power quickly, which is why aircraft use it to spin up engines and back up electrical systems.
Context Anchor
Seen in turboprop airplane electrical system descriptions, battery servicing information, and electrical abnormal or emergency procedures.
Derivation
The name is just a contraction of the two metals inside the battery: nickel and cadmium. 'NiCad' uses the chemical symbol style — Ni for nickel, Cad for cadmium — so the word itself tells you what the battery is made of.
Why Pilots Care
NiCad batteries deliver the high starting current turboprops need yet require temperature monitoring during recharge to avoid damage or fire risk.
Intuition Check
Do not assume a NiCad battery behaves the same as every other aircraft battery. It is a specific battery type with its own charging, maintenance, and temperature concerns.
Example Sentence 1
Before engine start, the crew checked that the NiCad battery was showing a healthy charge and normal temperature.
Example Sentence 2
During ground operations the crew watched the NiCad battery temperature to prevent overheating on recharge.