Li Ion batteries

[barry wilkins]

If you look at a battery ,say from a mobile phone or a sat nav there are three terminals, one is positive and one is negative. What is the other connection for ? Usually this is the center connection.
There is an impedance from this connection to the negative terminal,the only conclusion I can make is this other terminal is used to monitor or control ,perhaps charging rate or core temperature of the cells.

I do know on my Dell laptop there are three connections on the power socket, the center pin determins the type of power supply connected.

Do any readers know or have any info on this battery technology?

Barry Wilkins

[japlytic]

Re: Li Ion batteries

On 3.7V batteries, the third terminal is usually the thermal sensor.
With 7.4V batteries having three terminals, the third terminal is usually the middle of the 2-cell stack, to determine if both cells are charged evenly.