Identify this component?

[dfitz1000]

Hi, can anyone help me identify the component in the attached pic and what it is for?

It is part of a small battery pack (3 x AA cells in series) and it connects to the negative terminal of the pack and then to the white pin of the battery pack connector. Of the other two pins of the connector, the red one is connected to the positive terminal of the pack (obviously!) and the black direct to the negative terminal. I don't understand the point of this or what it is even!

I couldn't measure any resistance with a cheap multimeter, seemed to be open circuit. Also didn't seem to be a diode when checked with the meter, I may be wrong.

Any help appreciated!

[Richard Crowley]

It is most likely a thermistor (or some kind of temperature-sensing device).  Manufacturers put them into battery packs so they can monitor the temperature during charging.  That is one way of accomplishing faster charging times, as one of the modes is to pump as much current into them as long as you stay under some maximum temperature.

If that device is "open" then it is probably dead and would prevent the battery pack from being charged since the charger couldn't monitor the temperature.  If you try to put too much current into the battery pack without monitoring the temperature, you could quite literally burn the house down.

[dfitz1000]

Ok that makes a lot of sense now because the battery does not seem to be holding charge anymore. Thank you.

[SeanB]

Itshould be around 10k at room temperature, and if the battery is not holding charge the cells are dead.