iPhone, a lithium ion polymer battery is built in. This kind of battery is used repeatedly to undergo degradation,and life changing,discharge and frequency of use by”that day”is different.
It is about battery life would barely work, but the initial performance was significantly reduced from the state to do, or fail to operate in the sense of the result.
Apple’s official statement(link), the battery life and the service life, and in the”new battery until it needs to be replaced for the duration”, but specific figures are not shown. However, AppleCare+warranty subject to the”battery power storage capacity of the original 80%to less than degraded”and that”80%”below the time to have life and to have a General idea what it could be.
That is, the inherent storage capacity for the current(at the time of full charge)of power storage ratio to examine if it can,it is not. “Settings”→”Battery”→”Battery Status”in the order screen, open the”maximum capacity”of the item number to check it out. More than 80% if the problem is not 80%or less if you life past it(performance patient two)using state,and so on.
View this screen without a sudden shutdown began to frequent(perhaps the battery voltage drops cause),the rear is inflated(for battery pack degradation by swelling is the cause)and visible phenomenon in the life of the battery can can be determined. The performance put up on one ready for use at the Apple Store to book to replace the battery immediately.
Batteries the maximum capacity of the”life”that