The theoretical charging time is 90 minutes, and the actual charging time is about 2 hours. The battery capacity of iPhone4s is: 1420mAh. The charging specification of iPhone4s is 5V, 1000mA.

Computer state

When charging iphone with usb, please make sure that your computer is turned on. If the iphone is connected to a computer that is turned off or asleep, the battery of the iphone may be exhausted.

Sheath removal

If the sheath is not removed when charging the iphone, it will generate more heat and affect the battery life.

preference temperature

The suitable operating and storage temperatures of iphone are 0℃ to 35℃ and -20℃ to 45℃ respectively, and Iphone should be as close to room temperature (22℃) as possible, which is an ideal state.

Lithium battery maintenance

If you want to properly maintain the lithium battery, you must keep the electrons flowing occasionally, and charge it completely at least once a month, while using it.