Thread: Replacing headlight batteries

Originally Posted by gonetropo

although 18650 rates as 18mmx65mm, there is also mAh to be considered but also weher the battery is designed for a long slow output such as a backup light, medium output over medium time such as a headlight or big output short time like a taser gun

That would probably be the C-rate or C/20 rate. Lithium battery tech fares pretty well in terms of discharge-current, and for a headlamp I don't think it would matter. A fast-rate battery will still only output as much as the device needs. And usually cost more to boot.