World’s first Battery-less Cellphone Invented

Battery-less Cellphone
Image Courtesy: University of Washington
2 mins read

Technology is moving very fast. Washington University researchers have invented battery-less cellphone.

How the battery-less cellphone works?

Question arises ‘how a cell phone can work without having a battery? Is it really possible?


Well, the answer to this is ambient radio signal or light. It will give power to cellphone.

Today’s cell phones converts analog signals that convey sound signals into digital data. These digital datas are such that a phone can understand. This process consumes lot of energy.

The team of UW scientists and electrical engineers have eliminated power-hungry step. They took advantage of tiny vibrations in a phone’s microphone or speaker. Microphone or speaker vibrates when when a person talking into a phone or listening to a call.

An antenna connected to those components converts that motion and changes in standard analog radio signal emitted by a cellular base station. This process essentially encodes speech patterns in reflected radio signals in a way that uses almost no power.

To transmit speech, the phone uses vibrations from the device’s microphone to encode speech patterns in the reflected signals.

To receive speech, it converts encoded radio signals into sound vibrations that that are picked up by the phone’s speaker. In the prototype device, the user presses a button to switch between these two “transmitting” and “listening” modes.

Major advantage of technology

The battery-free phone does still require a small amount of energy to perform some operations. The prototype has a power budget of 3.5 micro-watts.

The UW researchers demonstrated how to harvest this small amount of energy from two different sources. The battery-free phone prototype can operate on power gathered from ambient radio signals transmitted by a base station up to 31 feet away.

Next move of UW Researchers

Next move of research team is to focus on improving battery-free phone’s operating range and encrypting conversations to make them secure. The team is also working to stream video over a battery-free cell phone and add a visual display feature to the phone using low-power E-ink screens.

A day is not so far when we would be using battery-free phones. Great job done by researchers.

Reference: University of Washington



Please enter your comment!
Please enter your name here