Q. Does rechargeable led bulb charge when the switch is off?

The answer is No that's not the right response. When the switch is turned off energy is no longer able to reach the light bulb therefore the bulb cannot be recharged. In order to have completely charged batteries during the next power loss rechargeable light bulbs must be charged or used normally during periods of electricity. When the electricity is on they function normally and while the switch is on they recharge. After a blackout they continue to shine because of an internal battery that can be charged. The average lifespan of a light bulb is two to eight hours.