Wireless wireless charging
The emergence of Qi and other wireless charging technologies has reduced people's cumbersome operations for charging devices to a certain extent. It is not necessary to find data lines or connections, and it is very convenient. Of course, this coil-based wireless charging method still requires the device to be in contact with the charging base, and is not really "wireless." However, the emergence of over-the-air wireless charging technologies such as uBeam can transmit energy through microwaves and realize a real over-the-air wireless charging experience at a certain distance. The device no longer needs to contact the charging stand, which is more convenient.

Slightly sci-fi, maybe in the future, we can use the WiFi and cellular networks to transmit power signals in the air, and charging becomes So Easy.
Do not need to charge the phone

Mobile phones do not need to be charged. It is also a viable direction. An engineer at the University of Washington designed a mobile phone that continuously absorbs solar energy through micro solar panels. The mobile phone does not even require a built-in lithium battery. Of course, the current technological power can only provide power for a very simple mobile phone, and it takes time to really apply it to smart phones.
Bioelectricity

Mankind is a kind of living creature that can continuously produce energy. In fact, these energy may also be converted into electricity. The Bill Gates Foundation currently develops a technology that can extract electrical energy from human urine, known as the "microbial fuel cell"; there is also a silicone structure that integrates nano-films that are applied to the skin to generate friction and generate electricity. Is very suitable as a source of energy for wearable devices.