Why Mobile Phone Batteries Has Three Terminals For Charging? Most Of The Time..

Many people in my knowledge are always confused about the mobile battery, i.e. why mobile batteries have three (3) terminals or sometimes four (4) terminals? Me too sometimes ago was not exactly knowing the answer for this. Many people think that the middle terminal is of ground or earth and many thinks that it is having the half potential difference (works as an internals potential divider); but all these beliefs are wrong.

You may easily understand that the two side wise terminals (except the centre one) are having the potential difference (voltage) to drive the mobile phone… or powers your mobile phones ; it is having the voltage of 3.7 volts (in general); one positive and one negative you easily see and measure using the multimeter. Nearly all mobile phones battery has three terminals and sometimes four terminals. But why and what is the use of middle or centre one terminal in mobile phone batteries?Mobile_Phone_Batteries_Terminals_(TheZeroLife.Com)

The centre one terminal in mobile phone battery is used for the sensing purpose, and the sensing is done by the mobile phone circuitry. As the batteries are charged by applying a controlled current through the charging circuit. While charging any battery some of the chemical and electric energy is converted into heat; and thus you must know that the batteries use to heat while charging. Overheating and over charging may damage your battery permanently, shortens the battery life or may lead to explosion.

Thus here is a need to control the heating of the battery during the charging and it is achieved by the centre one terminal of the battery. The centre one terminal is used to sense the temperature of the battery and accordingly changes the voltage levels to the output. This change in voltage is sensed by the charger circuit and the charger circuit accordingly controls the charging current to the battery. The battery charging circuit use to continuously sense this centre terminal; and thus temperature of the battery while charging; and accordingly varies the current or the charging rate (Voltage and Current). This centre one terminal allows the battery charge faster without damaging or shortening the life and overcharging. If some times Mobile phone batteries has 4 (Four) terminals, than one of the terminal is N/C (Not Connected) among four.  Also See Watch TV On Mobile Phones, Live TV On Mobile.

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Next times remember to answer if anybody asks you; why mobile phone batteries have three terminals?