Inductive Charging (a.k.a. Wireless Charging)

A perfect example of an old technology with improvements and alternate uses

Akin to the Maruti’s extremely eloquent “Kitna Deti Hai” ad campaign that so truly portrayed Indians’ fuel sensitivity when contemplating automobile value, the world over, one of the first things consumers think of when contemplating electrical devices is their power consumption; in the world of portable devices, the lowest common denominator is often power duration.

So dire is the situation (given our somewhat over-reliance on smartphones and tablets that it would almost be calamitous if we went off the grid), that many many inventors and companies have trudged the difficult path of finding different means and alternative sources to charge devices. They’ve been exploring solar, wind, water, tides and even motion as sources of energy.

On motion as a source, there is even a nightclub (Club4Climate in the UK) that as installed motion sensors under their floors. The sensors generate electricity when people dance. The harder they dance, the more the electrical energy produced. Now, the majority of the club’s power is produced by this amazing dance floor.

While its not yet possible to address the power needs of our devices through motion-charging, but given enough focus and belief, this could easily become a reality for smartphones and wearables soon.

Meanwhile, lets try and decipher a new technology — Wireless Charging (aka. Induction Charging). To an average person, this technology would imply the ability to charge a device remotely (over the air) without plugging them physically into chargers or even using a wire.

In reality, it is actually the use of electromagnetic field through physical contact to transfer energy. There are 2 parts to this magic:

The Transmitter: The transmitter is connected to a power source and sends the electricity through its induction coil, creating an alternating electromagnetic field.

The Receiver: This will also have an induction coil which converts the magnetic field around itself into electrical current and will thus power the receiver device. A more detailed diagram for the curious:

The popularity of this technology is getting a major boost as many device manufacturers and accessory makers are introducing wireless charging options for smartphones (which will have the transmitter coils in the “charging pad” and receiver coils in the smartphones’ covers respectively.

Such a set up allows you to charge your phone by just placing the phone on the platform shaped base. The base is the transmitter and the cover on the phone converts the phone into a receiver. This technology is further being improved where the phone manufacturers are contemplating putting the receiving coil inside the phone at the time of manufacturing so it is capable of charging wirelessly (like the NFC {near field communication} antenna on the back covers of the phones). The other improvement is also being made in the strength of the magnetic field, so that the device and the transmitter can be further apart, thus allowing you to be in proximity of the transmitter to charge your phone ( kind of like WIFI for accessing internet). This technology has been around since the early 1990s and may be present inside your homes as you read this article.

Oral-B rechargeable toothbrushes manufactured by Braun have used this technology since the 1990s. Most of you will recognize the humble toothbrush and the base that is attached into the power socket. The base with the raised knob houses the coil which is the transmitter coil whilce the hollow at the bottom of the tooth brush has the receiver coil, allowing it to harness the magnetic field.

The introduction of inductive charging is a perfect example of an old technology with improvements and alternate uses.

Originally published at Chip-Monks.