Large screen smart phones have brought users a very excellent touch screen experience, but long-term use is also a big challenge for the endurance of such cross-border models. In order to solve the worldwide problem of mobile phones having no power outside, people from all walks of life have racked their brains to launch various methods.

Crank Case 

Recently, Lucid Design Studio brought us the most tired "external battery" in history.

The Crank Case looks like an ordinary mobile phone protective case, but there is a blue puzzle behind it. If there is no electricity, it will come in handy. Pull out the blue small piece, you will find it is a pull ring, and then start to pull it down repeatedly!

There is a coil in the back cover of the Crank Case. The action of pulling down the pull ring drives it to charge the capacitor. This so-called charging is only an emergency measure and cannot replace the traditional charging, unless you can keep pulling the bracelet for three days and three nights.

Mipwr Dynamo

It is nothing new to equip the mobile phone with a manually charged back cover. Last year, the Mipwr team from the United States released an iPhone protective case called "Mipwr Dynamo" on Kickstarter.

Mipwr Dynamo can not only provide protection for your iPhone, but also allow you to charge your iPhone with your bare hands. It is very simple to use. When you find that the iPhone is almost dead, just take out the hidden handle from the side of the protective case and press it back and forth to charge your iPhone.

Mipwr Dynamo uses the electromagnetic induction power generation method to work. A magnet is installed in the protective case. When you press the handle on the side of the protective case, this magnet will also be driven to charge your iPhone through the voltage generated by cutting the magnetic induction line. When you press for your iPhone for 1 minute, you will get about 30 seconds of talk time.

Although it sounds that the conversion efficiency of this method is not high, it is undoubtedly a good emergency method when you cannot find a charger for the time being.

Hand charger

Keep away from the danger of explosion, return to history, hand-held charger.

Shake the crank handle to charge the mobile phone. Shake it for one minute to get the emergency power supply for 30 seconds. It is not mainly for the purpose of fully charging the mobile phone. In case of emergency, you can get the slightest amount of power to make a call or send a text message.

At present, smart phones are getting bigger and bigger, and their endurance, which has always been criticized, is also improving. However, it still can not meet people's needs, which has led to the birth of so many peripheral products. However, this kind of mobile phone back cover can not solve the problem from the source, and can only look forward to the emergence of new battery technology.