Middle School teacher: battery storage

[LK5]

Hello PF,
I am a middle school teacher in Humboldt county, CA and teach physical science to eighth graders. We are beginning our electricity and magnetism unit and have students have experimented with making a light bulb illuminate using a battery and copper wire. My question is, if we make a more permanent set-up with the wire attached to the battery and light bulb with electrical tape, would it be safe to keep our battery somewhere in the classroom? My concern is that the materials would become too hot and I need to create a safe place where students can observe the battery still powering the light bulb so their safety is not compromised. Are there any suggestions or previous set-ups that were successful? Thanks!

 

[jedishrfu]

You're doing an experiment like this?



Personally I wouldn't tape the setup together permanently as it makes it easier for the loose wire to accidentally short the battery and using a D cell as the source will get hot very quickly.

There were a some news stories floating around a few years about accidental fires started by 9v batteries left in junk drawers where the + and - posts could touch creating a short and starting a fire. The recommendation was to cover the posts with electrical when disposing of them and keeping them in their original packaging until you're ready to use them.

http://fireprotectiontesting.com/dangers-of-9-volt-batteries/

 

[berkeman]

Hello PF,
I am a middle school teacher in Humboldt county, CA and teach physical science to eighth graders. We are beginning our electricity and magnetism unit and have students have experimented with making a light bulb illuminate using a battery and copper wire. My question is, if we make a more permanent set-up with the wire attached to the battery and light bulb with electrical tape, would it be safe to keep our battery somewhere in the classroom? My concern is that the materials would become too hot and I need to create a safe place where students can observe the battery still powering the light bulb so their safety is not compromised. Are there any suggestions or previous set-ups that were successful? Thanks!

Holding the wires on the ends of a battery with electrical tape does not make a reliable connection. Just go to a local Radio Shack or similar store (or online), and get a 2xAA or 2xC battery holder. Then you can use whatever means to hook the wires up to a 2x<whatever> light bulb.

http://www.reuk.co.uk/shopImages/4-aa-battery-holder.jpg

 

[berkeman]

Maybe you could get the school to spring for one of these multi-experiment kits -- it would make it a lot easier to do multiple demonstrations, etc.

http://thenetworkgarden.blogs.com/photos/uncategorized/2008/05/30/150inone.jpg

 

[jedishrfu]

Also even more fun is the Little Bits sets:



They use magnets to create click together circuits. They even have a smart home kit where you activate the circuit via a smart device and the internet.

 

[LK5]

Holding the wires on the ends of a battery with electrical tape does not make a reliable connection. Just go to a local Radio Shack or similar store (or online), and get a 2xAA or 2xC battery holder. Then you can use whatever means to hook the wires up to a 2x<whatever> light bulb.

http://www.reuk.co.uk/shopImages/4-aa-battery-holder.jpg

Thank you for the responses and suggestions. I think I will look online for the battery holder; I'll respond with how long our bulb stayed illuminated (hopefully).

 

[alw34]

My concern is that the materials would become too hot and I need to create a safe place where students can observe the battery still powering the light bulb so their safety is not compromised.

If you match the light power to the battery power, say, as is routinely done in a flashlight, and have secure electrical connections, over heating should not be a problem. You'll also have to decide when the battery is 'dead' because as you know a light will gradually get dimmer and dimmer. In solid state devices, a 1.5 volt dry cell battery might no longer function at say 1.1 volts, but your light will still offer some illumination. And there is a decent chance once the light can no longer been seen, if you open the circuit, and leave if off for a few hours, the battery is likely to 'recover' enough to once again briefly illuminate the light.