🔋 Charge Rate (1C, 2C...)
How fast a battery is charged, as a multiple of its capacity — 1C on a 5000mAh pack is a 5A charge. Faster charging (higher C) stresses the pack more and shortens its life.
What it actually does
Charge rate is how fast you push energy back into a pack, expressed as a multiple of its capacity. 1C means charging at the pack's own capacity in amps — a 5000mAh (5Ah) pack at 1C is 5A, and takes roughly an hour. Charging gently is one of the easiest things you can do to make packs last.
In practice
Most LiPo packs are safely charged at 1C, and many modern packs are rated for more. Higher rates mean more heat inside the cells, and heat is what ages them. If you are not in a hurry, 1C is always a defensible choice.
Worth knowing
Set the correct cell count and chemistry on the charger before starting, every single time. Selecting the wrong cell count is the most common charging mistake and the charger cannot always detect it for you.