How does a fully charged mobile phone lose its charge when left unused? Curiosity corner
Q: How does a fully charged mobile phone lose its charge when left unused for several days together?
Answered by
Kingshuk Roy
IISER, Pune
Lithium-ion battery chemistries are associated with self-discharge phenomena. A passivation layer develops on the electrodes over time (on performing several charging-discharging cycles) which results in self-discharging of the battery. It means internal chemical reactions reduce the stored charge of the battery without any connection between the electrodes or any external circuit. Studies show a self-discharge rate of Li-ion battery is 5% in 24 hours, then 1–2% per month. It must be borne in mind that even when the phone is kept idle, there are a lot of applications working in the background like phone-watch, calender, to name a few. These applications in-turn cause a charge loss.
