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Battery has 3 wires??!!!


Sorry if I'm being naive but I just got a lithium -Ion rechargeable battery pack (8.4V 2000mAh(2C)) and guess what..Yeah it has got 3 wires (a red one,a yellowish creamy one and a black one).Now could u please tell me what each one means and also the need for doing this.Btw what does 2C mean ?

Thanks in advance.


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Turns out that the creamy color wire was the tap to

1)Get half the voltage if needed.(I checked it with a multimeter)

2)To ensure that each cell gets fully charged when pluged into charging.

As for the 2C rating that is the "Discharge Rate" which basically let's you know how fast can you discharge that battery pack safely.

Read the section on "Discharge Rate" on the following page to learn more:


In the off-change your pack might actually be a Lithium polymer pack I advise you to read the whole page, since often those packs are unshielded and mishandling those can easily lead to fire/explosive hazards.

Did your battery come with any specifications or documentation? What model is it?

Here's a discussion I found researching your question. http://www.rcgroups.com/forums/showthread.php?t=1568680

It lists two reasons why you might find three wires on a battery pack.

Here's another. http://www.edaboard.com/thread108656.html

This looks like the most likely answer. http://forum.allaboutcircuits.com/showthread.php?t=24841. The third lead is for monitoring the temperature during charging.