two week lightbulb

[forrest]

Hi
i'm trying to figure out how to power a small lightbulb with a battery for two weeks
they're going to be sealed inside a 4x4x4 box and shipped, so it can't be plugged in
i was wondering if anyone knew what combination of battery and lightbulb i should use
LED bulbs? 9Volts? I have no idea. I've never made a homemade battery-bulb before.
I just know it has to be small and stay glowing for about two weeks straight.
If anyone could help me out I'd be the most grateful man on the internet.
Thanks!
-forrest

 

[sirch]

I've got to ask why???

 

[(*steve*)]

the question "why" is important, because without it we could come up with a totally inappropriate answer.

Knowing if it is for heat or light is important, and how much light and/or heat will essentially tell us how much power is required. From that it is a simple matter to determine the size of battery required (or alternately how long a given battery will last).

If it's going to be in either a very hot or cold environment then that can affect things too.

 

[BobK]

... a 4x4x4 box

cm, m, in, ft, cubits?

Bob

 

[forrest]

Essentially, it's for an art project. It's for light, not heat. Ideally there would be as little heat as possible because it will be shipped across a couple states while glowing. The idea being that the package is opened with light coming out of it, and to keep glowing for as long as possible. The two week thing was just a rough estimate.

the question "why" is important, because without it we could come up with a totally inappropriate answer.

Knowing if it is for heat or light is important, and how much light and/or heat will essentially tell us how much power is required. From that it is a simple matter to determine the size of battery required (or alternately how long a given battery will last).

If it's going to be in either a very hot or cold environment then that can affect things too.

 

[forrest]

4x4x4 inches*

 

[BobK]

It might be better then, to rig a switch so that the light comes on when the box is opened.

Bob

 

[CocaCola]

A couple of good D cells should power a single LED for that period of time... But, there are undoubtedly better ways depending on what compromises you can accept...

 

[duke37]

You could extend the time by only energising for a time after a movement.

You could make a 'Jack-in-a-box'

 

[(*steve*)]

Yeah, I agree with many of these comments.

If the box isn't translucent then I'd have a catch on the box which turns off the bulb when it is closed.

So opening the box would reveal an already lit LED.

You might even get away with a coin cell for this if the box is only opened rarely.

It would be best to have a latch that closes automatically as the lid is closed though.

 

[sirch]

Depending on how complex you want to make it, you could have a low light output when the lid is closed and then ramp up the power when it is open. Here are some figures for the caving light I use, in the low range you will get a couple of days off AA batteries, so something similar running of a Lead Acid battery may get you over a week.

Do you need to get anything else in the box?

 

[Young]

My advice google for battery life calculator there are many online,calculate the battery life of different batteries using the formular you get,eg rechargeable and unchargeable also remember that with a load the battery life will decrease so calculate it in such a way that even with a large load it will last for the required period

 

[JMW]

Before you proceed, check with the shipping company you plan to use. Many will not permit this. Heaven forbid it goes to a Postal Inspector and is subjected to some sort of scan and turns up positive. Even though it is harmless, it will probably be destroyed.

 

[(*steve*)]

If sent by an appropriate means, you'll be fine.

We ship containers full of dry ice and containing monitoring electronics that look way more interesting than a battery and a bulb.

The only thing they're likely to be interested in is the battery. Pick something safe (i.e. not lead acid or LiPo and they'll be far less concerned.)