Definition
A continuous low-rate charge applied to a storage battery to keep it at full capacity by replacing the small amount of energy lost through internal self-discharge. The charging current is just high enough to offset self-discharge without overcharging or overheating the battery.
Plain English
A slow, steady flow of electricity into a battery that keeps it topped up without overfilling it. It replaces the small amount of charge a battery naturally loses while sitting unused.
Context Anchor
Seen in aircraft battery maintenance, hangar storage, and charger or battery-maintainer instructions.
Derivation
The word 'trickle' describes a small, slow flow — like a thin stream of water. The term captures the idea of electricity flowing into the battery at a slow, steady rate rather than pouring in quickly.
Why Pilots Care
Keeps the battery ready for reliable engine starts and emergency electrical power while avoiding the damage that faster charging can cause to aircraft batteries.
Intuition Check
A trickle charge is not a quick way to recharge a dead battery. It is a slow maintenance charge used to keep a battery topped up.
Example Sentence 1
The maintenance crew connected the aircraft battery to a trickle charge unit while the airplane sat in the hangar over the winter.
Example Sentence 2
Many hangar power systems apply a trickle charge to parked aircraft so the battery remains serviceable without constant attention.