Charging battery over the air - wireless charging (a.k.a. inductive charging)

Remember that it was just a few years back when the industry players of devices carrying a rechargeable battery (e.g. mobile phone, bluetooth headset, GPS, digital camera, digital camcorder, digital voice recorder, ... etc.) unified their charging interface to use USB or mini-USB or micro-USB, so that we no longer need to carry charging adapter and charging cable for each and every of the devices, as they can now share a common charging adapter and common USB charging cable.

That move has also made possible for car or furniture to provide USB port featuring charging capability to our mobile devices, and the invention of portable power bank.

What's next?

I think the next move for the industry players is to do away the charging cable and embrace the wireless charging (a.k.a. inductive charging) technology.

Wireless charging involves transmission of power contactlessly (over the air) from the charging base station (transmitter) to the receiver using electromagnetic field. In fact, this charging technology has been used in Oral-B rechargeable toothbrush since the early 90s.

Nowadays, there are already several mobile phones such as Nokia Lumia 820/920, Google Nexus 4 and HTC Droid DNA for Verizon support wireless charging with the Qi standard, and there is rumour for the upcoming Samsung Galaxy S IV to join the bandwagon too.

Imagine what will happen to our live in the near future when the wireless charging technology is more widespread:

• The home theatre system surround speakers can be truly wireless, without the need of power cable.
• The iRobot or other similar robotic cleaners can be recharged over the air and need to returning to its base station when battery power is low.
• Workstation or table top can be the charging station for our mobile devices (including laptop). When we put our mobile devices on top, they are automatically recharged.
• Restaurant, hotel and other places can offer "hotspot" charging service in the same way they are offering Wifi service now.
• Hybrid or electrical car can be charged when parked at the garage or parking area with the charging base station on the floor.

And possibly, the following scenario could happen in the future too:

• When one mobile device (such as a phone) is having low power, it can borrow the power from another mobile device (such as another phone, or a GPS, or a "wireless powerbank") by wireless transmission.
• More home appliance become wireless (kettle, blender, TV, ...) and the amount of  power socket needed in our house/office/building can be substantially reduced.