Mobile phone battery is a high efficient Lithium Ion or Lithium Polymer battery that can deliver much power for long time. In an ordinary Mobile phone, a fully charged battery can power up to 3 or 4 days. But in Smart phones, the battery drains too fast because many applications are running simultaneously. To extend the life of battery we need to know some facts about the charging because the most important cause of battery breakdown is improper charging.
1. The mobile phone battery is shipped from the company with 40% charge inside so the new battery must be charged for 24 hours to get fully charged. When we plug in the charger, during the initial stage, the battery will be in the Fast Charge mode and takes more current. After sometime it shows Full charge, but actually it is only 70% charge. So do not remove the charger. Allow some more time for Trickle charging to attain 100% from 70%.
2. Use a good quality charger preferably, the one supplied along with the Mobile phone. Most Mobile phone battery is rated 3.6-3.7 volts. The charger should have voltage and current regulations. The low cost chargers do not have these facilities and simply provides 5 volt DC.
3. After the first full charge, it is better not to charge fully in the subsequent days. Lithium ion batteries do not need to be fully charged and high voltage stress the battery. So avoid the practice of charging the battery daily. Lithium Ion Batteries cannot absorb overcharge. Once fully charged, the charge current must be cut off.
4. Turn off the Mobile phone, when it is charging because the battery will stress for charging as well as discharging.
5. Don’t allow the battery to drain very low. The phone has the facility to shut off if battery is low. The BSI (Battery Status Indicator) pin in the battery (3rd pin) is meant for monitoring this.
6. Watch the charging process. If the battery or Phone shows unusual heat, stop the charging and remove the battery. If the battery is too hot (charging will give some heat), that battery is shorted and not safe.
7. Do not use the phone during charging. It has 3 disadvantages. 1. Battery will strain for charging as well as discharging and it will not charge properly. 2. Radiation level is very high during charging and just after fully charged. 3. The charger is based on SMPS and the 230V AC is directly using by dropping the voltage and converting to DC. Any problem in the Mains line can damage the charger and high volt appears in the phone leading to a shock hazard.