Will it stay lit?

The experimental method is useful for figuring things out, but it is time consuming. Luckily many people like to share their results thus avoiding unnecessarily redoing lots of work. This is especially good when it saves my time (my time being very valuable). So I’m glad I found a recent exploration of powering LEDs just by connecting them to a small “coin” battery, which is not unheard of (see LED Throwie) but not the standard procedure in most circuits. Happily the findings are good news.

Normally when you don’t stick a resistor (something that stops too much current from flowing through a device) in series with a LED the LED starts to burn and short out: not good unless you like the smell of burning plastic. But small 3 volt batteries like those used in remote controls and so on have an internal resistance in them which prevents a death of flames for a LED attached to them. Additionally, with a white LED that needs about 3 volts to light up the basic circuit (LED + battery) will stay lit for over a week. That’s the key piece of info I required.

That’s precisely what I needed to know for my Ping Pong Pumpkins project which I will be treating the world to this Thursday in a make-your-own event. It would be some trick to have them not last through Halloween.