9 volt battery get's hot

[d-minus]

O.K. i wanted to install a prewired led in my radio shack meter so i got a 9v battery a hard shell top lead for battery at radio shack and got a green led (just to try it) out of my parts shelf until i could get a white one. Also got a miniture toggle switch from radio shack,now i put the black leads together and the red leads together from the led and the battery. And soldered them to the switchIt works BUT, if i leave the top cap on the battery it will get hot ,so i take the cap off the battery let it cool 30 minutes put it back on leave it for hours and it will not get hot. Same thing goes if i turn on the led. Connections are not touching.Switch is a spst 3amp rating at 250v 6 amp at 120v. Also tried flip flopping wires on switch still the same. What's up with this. I have hooked other things up like this with no problem. I don't understand. Thanks for any help. Daniel

[pabxone]

Have you put a resistor in series with 1 lead of the LED ?

LEDs need a dropping resistor if being powered by anything over 2 volts.

For 9 Volts you need a 330 Ohm 1/4 resistor to work correctly.

Here's a good primer on powering LEDs :- http://www.evilmadscientist.c ... -for-leds/

[d-minus]

Yes they have a resistor, they came prewired with it. I hooked it back up this morning a 9:00 but it has not got hot yet. this is the problem it might get hot then it might not. Thanks. Daniel

[jessejamesdallas]

Yes they have a resistor, they came prewired with it. I hooked it back up this morning a 9:00 but it has not got hot yet. this is the problem it might get hot then it might not. Thanks. Daniel

Samsung battery?

[d-minus]

JJD, Energizer industrial. (did not have a duracell) Daniel

[420Snowman]

Hmmmmm, this is strange. Why would it intermittently get warm then other times not..... Hmmmmm

[d-minus]

Well , it was the mini switch. changed it out to a 12v rocker switch for car rated for 10 amps. problem solved. Mini switch was rated for 125v,1.5 amp. I don't understand it but that took care of it. D-minus

[sonoma]

good deal. some times some thing just does not work well in a application.

[MDYoungblood]

You should check out some of the 9v battery YouTube's, a couple of them are amazing watching how easy it is to heat them up to melting temperature.

3's

Greg

[d-minus]

Thanks, i'll check them out. D-minus