How to Make a Magnetic Induction Battery Charger

Warning: It is advised not to experiment if you are not familiar with sorting out the polarities and delicate handling of mobile devices or you may not do it with a new, expensive mobile having a fully charged battery intact!

Having a Smartphone is not an odd thing and every one of us need one when we are out somewhere or on a travel. It is the only way to stay connected to your friends, family members and to your community. So, having it ready, to connect to everyone is important. For this you need to have a consistent power source so that you can charge your mobile whenever you need it get charged quickly.

But the fact is that you cannot have a power source everywhere. So it could be a great idea if you can get your phone charged using a wireless, magnetic charging pad. In case you are hearing about it for the first time, you may follow the following steps to get to know the process in detail.

Take your old mobile which you may use when you are out somewhere or have it as a spare mobile, and convert it into a magnetic charging mobile with a few simple steps you can find below:

Things you’ll need

• A scissor

• 4 magnets

• Hot glue

• Solder gun

• Small pieces of wires

Important steps

1. Take out the back cover of your mobile to expose the battery area of the mobile and after that make sure you remove the battery as well. Be sure that your mobile is not connected to any other accessory or charging port in any way.
2. After removing the cover and the battery, remove some screws that keep the mobile’s internal structure safe. When you remove them you will be able to pull out the internal circuit or the whole internal structure in front of you to see through it.
3. Find out the micro-USB charging port and check its polarities by using the Multimeter. You will be able to locate the positive and negative polarities very easily.
4. Take small wires and connect them to the correct polarities as red with the positive and black with the ground pole. Solder the wires very carefully as if you don’t you may damage your mobile.
5. Make two marks on the back of the cover having the port, connected to wires to take out the wires properly. You can make them with the help of a hot pointed string or a thin rod.
6. In addition to these holes, you also need to have medium sized holes on the back cover approximately of the size in which you can fix in two small sized round magnets. You can do it by using scissors.
7. Take out the wires from there and assemble the mobile with the wires pulled out carefully from the holes.
8. Connect the two wires to the magnets you will be placing in the tow bigger holes. You will have to solder them carefully and never heat the magnets for long as it will ruin their magnetic capacity.
9. Now your phone is ready to be charged via the magnet power bank made with other two of the same sized magnets.
10. Take the two magnets you have and join them using a USB wire and fix on a foam board to give you a portable magnetic power bank or you can hot glue two magnets on your table to make a charging dock where you can place your mobile for charging.

​Conclusion

Make sure you are able to sort the polarities and place the magnets in the correct positioning as you can see you can only place opposite poles overlapping each other otherwise it will be repelled so keep that in mind while making the dock. Also you need to use the solder gun carefully without overheating any of the components as the mobile and the magnets both are not too much adaptable to high heat and should be kept away from extreme heat for sure. In case you are not sure about carrying out the whole process, you should take help from expert who may know the technical aspects so that you don’t have to ruin your mobile.

Learn how to wirelessly charge your iPhone with Qi-certified charging accessories.

What you need

• iPhone SE (2nd generation)
• iPhone 11
• iPhone 11 Pro
• iPhone 11 Pro Max
• iPhone XS
• iPhone XS Max
• iPhone XR
• iPhone X
• iPhone 8
• iPhone 8 Plus

Your iPhone 8 or later features integrated wireless charging that allows for an easy and intuitive charging experience. Your iPhone works with Qi-certified chargers that are available as accessories and in cars, cafes, hotels, airports, and furniture. Qi is an open, universal charging standard created by the Wireless Power Consortium (WPC).

There are many Qi-certified chargers available in the market that charge an iPhone with the latest version of iOS at rates up to 7.5 watts. These chargers are available at the Apple Online Store and Apple retail stores.

Other Qi-certified chargers might vary in functionality and performance. If you have questions, contact the manufacturer.

Charge wirelessly

1. Connect your charger to power. Use the power adapter that came with your accessory or a power adapter recommended by the manufacturer.
2. Place the charger on a level surface or other location recommended by the manufacturer.
3. Place your iPhone on the charger with the display facing up. For best performance, place it in the center of the charger or in the location recommended by manufacturer.
4. Your iPhone should start charging a few seconds after you place it on your wireless charger.

You should see in the status bar.

Learn more

• Wireless charging uses magnetic induction to charge your iPhone. Don’t place anything between your iPhone and the charger. Magnetic mounts, magnetic cases, or other objects between your iPhone and the charger might reduce performance or damage magnetic strips or RFID chips like those found in some credit cards, security badges, passports, and key fobs. If your case holds any of these sensitive items, remove them before charging or make sure that they aren’t between the back of your iPhone and the charger.
• If your iPhone isn’t charging or is charging slowly and your iPhone has a thick case, metal case, or battery case, try removing the case.
• If your iPhone vibrates—when it gets a notification, for example—your iPhone might shift position. This can cause the charging mat to stop providing power to your iPhone. If this happens often, consider turning off vibration, turning on Do Not Disturb, or using a case to prevent movement.
• Depending on the charging mat you have, you might hear faint noises while your iPhone charges.
• Your iPhone might get slightly warmer while it charges. To extend the lifespan of your battery, if the battery gets too warm, software might limit charging above 80 percent. Your iPhone will charge again when the temperature drops. Try moving your iPhone and charger to a cooler location.
• Your iPhone won’t charge wirelessly when connected to USB. If your iPhone is connected to your computer with USB, or if it’s connected to a USB power adapter, your iPhone will charge using the USB connection.

Information about products not manufactured by Apple, or independent websites not controlled or tested by Apple, is provided without recommendation or endorsement. Apple assumes no responsibility with regard to the selection, performance, or use of third-party websites or products. Apple makes no representations regarding third-party website accuracy or reliability. Contact the vendor for additional information.

Introduction: Elveet. Kinetic Charger Powerbank

Once I was on a trip and I had a problem with recharging my gadgets. I traveled for a long time on the bus, did not have the opportunity to charge my phone and knew that I would soon be without communication.

So came the idea to create a kinetic charger, which will not depend on the power outlet.

If you need to recharge your gadget on a trip, hike, on the beach or in transport, then Elveet will help you. You can just shake Elveet or put it in your bag (backpack) and go to work (go hiking, to the beach, to the mountains, etc.). The device is charging when you are moving.

Elveet is a kinetic charger.
The principle of operation Elveet is based on the phenomenon of electromagnetic induction

Step 1: Component Parts of the Elveet

1. The Inductor consists of a 9-magnetic Halbach array and three coils.

2. PCB contains an inductor 200mA step-up-converter, a battery charger, and a battery step-up converter 5V 2A output.

3. The lithium-polymer battery 2800 mAh.

4. The case consists 4 parts and is made with 3D Printer.

The whole project is created in Fusion 360.

Step 2: Elveet Inductor

The inductor converts the kinetic energy of your movement into an electric current. The efficiency of the inductor is the most important parameter. The amount of accumulated energy in the internal battery depends on the efficiency of the inductor.

The inductor consists of three coils, a Halbach magnetic array, and three diode bridges.
The working field of the coil is the part above which the poles of the magnets pass, that is, the longer this part is, the more energy we can get.

Further, the outputs of each coil are connected to the diode bridge, that is, the coils are independent in voltage. And the current of all three coils is summed up after the diode bridges.
Diode bridges use Schottky diodes with very low forward voltage PMEG4010 produced by Nexperia. These are the best diodes for such applications and I do not recommend changing them to others.

The magnetic Halbach array concentrates the magnetic field on one side. On the other side, the magnetic field is very weak.

Halbach array requires almost double the number of permanent magnets but the efficiency of the Halbach assembly is very high.

The magnetic array passes over two parts of each coil and always the poles pass over different parts. Since the coils are electrically independent due to diode bridges, their influence on each other is excluded.

The inductor uses an assembly of 9 neodymium magnets 5X5X30mm N42. Two more magnets 2X4X30 N42 are used as springs.

The efficiency of the inductor depends on the rate of change of the magnetic field. For this, the path of the magnetic assembly is increased. Thus, the rate of change of the magnetic field is increased substantially due to the large acceleration of the magnetic assembly during motion.

This inductor is much more efficient than an inductor with a cylindrical magnet in the center of the coil. The cylindrical inductor has only the upper and lowers working part of the magnet. The middle part of the cylindrical magnet almost does not work in the current generation. Therefore, its efficiency is low.

The Elveet inductor has a 4-pole magnetic system which is directed strictly perpendicular to the wires of the coils.

After the diode bridges, the current of the coils is summed up and fed to the converter and charger board.

Step 3: Elveet PCB

The circuit and all components of the boards.
It contains three main parts:

1. Step-up 200mA converter inductor current. The chip NCP1402 is used.

It is a boost converter that operates from 0.8 volts and gives a fixed voltage of 5 volts and a current of up to 200 mA. The task of this chip is to provide a comfortable voltage for charging the battery.

2. Charge device chip STC4054

This chip receives 5 volts from the inductor or from an external source (via micro-USB) and charges a Lithium-polymer battery with a capacity of 2800 mA. The inductor current and the current from the external source are decoupled via Schottky diodes.

Also, the second pair of Schottky diodes allow Elveet to operate as an uninterrupted power supply, that is, you can charge Elveet and receive current from it for your devices at the same time.

3. Step-up output converter. It boosts the battery voltage to 5 Volts and provides a current of up to 2 Amperes to power the gadgets. In this case, the LM2623 chip is working.

A good feature of the LM2623 is an internal high-power transistor and an output current of up to 2 Amperes with low output voltage ripple. The output voltage is fed to a standard USB connector.

In addition to these parts, the board has a touch-sensitive load switch (for example a powerful traveling lamp or other constant loads). There are also output pins for connecting the wireless charger instead of the USB cable, but this option is designed for the future.

­ Unless you are particularly organized and good with tie wrap, you probably have a few dusty power cord tangles around your home. You may have even had to follow one particular cord through the seemingly impossible snarl to the outlet, hoping that the plug you pull will be the right one. This is one of the downfalls of electricity. While it can make people’s lives easier, it can add a lot of clutter in the process.

For these reasons, scientists have tried to develop methods of wireless power transmission that could cut the clutter or lead to clean sources of electricity. While the idea may sound futuristic, it isn’t particularly new. Nicola Tesla proposed theories of wireless power transmission in the late 1800s and early 1900s. One of his more spectacular displays involved remotely powering lights in the ground at his Colorado Springs experiment station.

Tesla’s work was impressive, but it didn’t immediately lead to widespread, practical methods for wireless power transmission. Since then, researchers have developed several techniques for moving electricity over long distances without wires. Some exist only as theories or prototypes, but others are already in use. If you have an electric toothbrush, for example, you probably take advantage of one method every day.

­The wireless transmission of energy is common in much of the world. Radio waves are energy, and people use them to send and receive cell phone, TV, radio and WiFi signals every day. The radio waves spread in all directions until they reach antennae that are tuned to the right frequency. A similar method for transferring electrical power would be both inefficient and dangerous.

For example, a toothbrush’s daily exposure to water makes a traditional plug-in charger potentially dangerous. Ordinary electrical connections could also allow water to seep into the toothbrush, damaging its components. Because of this, most toothbrushes recharge through inductive coupling. See the next page to learn more about how inductive coupling works.

Inductive coupling uses magnetic fields that are a natural part of current’s movement through­ wire. Any time electrical current moves through a wire, it creates a circular magnetic field around the wire. Bending the wire into a coil amplifies the magnetic field. The more loops the coil makes, the bigger the field will be.

If you place a second coil of wire in the magnetic field you’ve created, the field can induce a current in the wire. This is essentially how a transformer works, and it’s how an electric toothbrush recharges. It takes three basic steps:

1. Current from the wall outlet flows through a coil inside the charger, creating a magnetic field. In a transformer, this coil is called the primary winding.
2. When you place your toothbrush in the charger, the magnetic field induces a current in another coil, or secondary winding, which connects to the battery.
3. This current recharges the battery.

You can use the same principle to recharge several devices at once. For example, the Splashpower recharging mat and Edison Electric’s Powerdesk both use coils to create a magnetic field. Electronic devices use corresponding built-in or plug-in receivers to recharge while resting on the mat. These receivers contain compatible coils and the circuitry necessary to deliver electricity to devices’ batteries.

A newer theory uses a similar setup to transmit electricity over longer distances. We’ll look at how it works in the next section.

Published by Alexandre Laurent on 12.27.2019 – 3 min

With induction charging, there’s no need to hook your car up to a charging cable. Just park over a special device and the battery charges wirelessly. How does this technology work, and what implications does it have for the automotive industry?

Discovered back in the first half of the 19 th century, electricity transmission by induction has already culminated in many real-world consumer applications, from medical implants to smartphones and electric toothbrushes. In New ZOE, for example, there’s an induction charger that makes it possible to charge compatible smartphones wirelessly.

What is wireless induction charging?

Wireless charging is based on the principle of electromagnetic induction. When an electric current is sent through a coil (a wound-up cable), it creates a magnetic field whose action generates another electric current in a second coil that’s some distance away.

This way electricity can be transferred from one device to another without physical contact. Regular applications for induction charging still need the charger and receiving device to be near to each other. That’s why these charging systems are sometimes called “near field.”

Induction charging and electric cars

In the electric vehicle industry, induction charging could make it possible for cars to charge without a special socket or cable. In a static charging scenario, the electricity is still supplied by the charging station or Wallbox, but the electric current is sent to the car wirelessly via a charging pad over which the car just needs to be parked.

There’s no need to walk around the vehicle to plug in your cable, or tap your badge on the charging point: charging will start automatically as soon as the emitting and receiving coils are facing each other.

What is the future for induction charging?

The real future of wireless charging, though, is not about the home, but rather its use out on the road, thanks to dynamic induction charging.

The principle: rather than being confined to parking lots, the charging coils are set right into the road. The electric car passing over them picks up their magnetic field and turns it into electricity, which supplies the car with energy while being driven and delays the need to stop at a charging station.

Renault has been taking part in research and development projects involving dynamic induction charging since 2012. For example, the Group supplied two Kangoo Z.E. vehicles fitted with a coil for the European Fabric research project, which led to the creation of a test route in Satory in the Greater Paris region. The challenge here is considerable: the installation of dynamic charging facilities would make it possible to significantly lengthen the range of electric cars without increasing their battery capacity.

Copyrights : IGphotography, Anthony Bernier

The following includes tips on how to build and use a homemade magneto magnet charger.

The cores of the electromagnet are made of soft bar steel one inch in diameter and three inches long. They are secured to a steel base measuring 5-1/4 by 1-1/2 by 5/8 inch and are provided with pole pieces measuring 1-3/4 x 1-3/4 by 5/8 inch. All contacting surfaces should be absolutely flat and square so that there will be good metalic contact over the entire surfaces. Before the wire is wound on them, the magnet cores must be insulated. A spool may be formed by placing fiber or cardboard washers around each end of the magnet cores and then wrapping the magnet cores themselves with several layers of electricians tape. The winding for this recharger is for use on 6 or 12 volt direct current, from automobile storage batteries. Applying three layers of No. 12 double cotton covered magnet wire is preferred. However, No. 12 gauge copper thermoplastic covered type “TW” house and building wire will give satisfactory service and results. Wind the wire around the electromagnet cores as shown in the illustrations and then wrap tape around the windings, to hold them in place. Mount the recharger on a wooden base large enough to also hold a single pole switch and a binding post.

CAUTION, the switch is a must, as the recharger draws high amperage from the battery. As a result, the battery has a tendency to produce some flammable gas, and any sparks around the battery vents could cause a fire and/or an explosion. Therefore, do not connect or disconnect the lead wires from the battery when the recharger is turned on. The windings will heat up quickly when in use; therefore, the switch should be closed for only a few minutes at a time. When a magneto is taken apart for any reason, it must be assembled with the magnets in the same relative position as formerly, otherwise their polarity may be reversed and the magneto will be inoperative. The magnets must never be left off the magneto even temporarily, without placing a steel bar across their poles to serve as a keeper. Unless this is done, they will lose their magnetism rapidly. Re-magnetizing the magnets of a magneto that has become weakened through long use is a simple process.

It is important that unlike poles of the magneto magnets and of the electro magnets be brought together; i.e. the North pole of the magneto magnet to the South pole of the electromagnet and vice versa. To insure this, the current should be turned into the electromagnet and magneto magnet suspended over it on a string. Starting at a distance of about 12 inches, slowly lower the magneto magnet. As you begin to lower the magneto magnet towards the electromagnet, the magneto magnet will automatically seek the proper polarity by swinging around and will then be strongly attracted to the electromagnet.

In recharging, set the magnet on top of the recharger after its polarity has been determined, and rock the magnet back and forth on its pole edges a number of times. Then lay it on its side with its poles away from you and extending just beyond the far edges of the electromagnet poles. Apply a keeper to the magnet poles, switch off the current and withdraw the magnet sideways from the recharger. The keeper should remain in place until the magnet is reassembled on the magneto.

Someday soon, your parking space could charge your car

Senior Reporter, Computerworld |

It feels a bit like being at a magic show, watching David Schatz hold a light or smartphone feet above a power pad to demonstrate how magnetic resonance wireless technology can charge any device over distance.

Schatz, director of business development at WiTricity in Watertown, Mass., can even show off the wireless “room of the future,” where lamps, cell phones – you name it – can all be powered through the air, no matter where they are in the room.

WiTricity, however, won’t be selling any of the wireless products it demonstrates. Instead, the company’s future is in selling licenses for others to use its patented designs to build products. WiTricity has few, if any competitors, for its flavor of wireless charging, which it calls highly resonant wireless power transfer.

“They were one of the first to showcase this resonance wireless power transfer, which offers greater distances between coils versus inductive charging, which requires tight coupling between transmitter and receiver,” said Jason dePreaux, a principal analyst for the Power & Energy Group at IHS Research. “My impression of WiTricity is that they’re keeping it very open [for the market].”

China-based 3DVOX Technology claims it successfully developed a “3D Power System” in March 2012 that — from a single 1.5-foot by 1.5-foot box — can power an entire room full of electronics. The company claims its Widely Magnetic Field Launching and Focus Magnetic Field Receiving technologies are powerful enough to magnetically resonate power over many feet.

Inductive vs. resonance wireless charging

To date, products on the market have been built around magnetic induction charging techniques, which require that a mobile device be in contact with a charging surface, such as a charging pad. The leading charging pad supplier has been Duracell’s Powermat technology.

Resonance charging like WiTrcity’s allows an enabled device to be placed up to several feet away from a power source for charging.

Resonance charging is based on the same transmitter/receiver coil technology as magnetic induction, but it transmits the power at a greater distance. So, for example, a mobile device could be charged when laid next to a laptop with resonance charging capability or, in the case of WiTricity, it could be charged from feet away.

Lots of possibilities

The consumer product possibilities are endless for WiTricity’s technology, from office desks and kitchen cabinets with embedded wireless chargers to pads buried in concrete that can charge electric cars parked in home garages and parking lots. WiTricity has even built a receiver for a solar panel, which eliminates the need to have any wires pass through a roof.

Imagine a wireless television, fed both power and media content (using Bluetooth) wirelessly. WiTricity has one.

Medical devices could also be powered with the technology WiTricity offers. For example, artificial heart pumps today must be hardwired to a battery pack worn by a patient. Wireless charging could be less invasive, helping to avoid infections in the areas where wires pass through a patient’s skin.

Inductive charging is the most commonly used method of wireless charging available today. Through electromagnetic induction, inductive charging uses an electromagnetic field to transfer energy between two objects. As a wireless power expert, we like to explain how inductive charging works exactly.

How does inductive charging work?

In inductive charging systems, energy is transferred between coils by a magnetic field via inductive coupling. The alternating magnetic field is generated by the transmitter coil. This coil induces an alternating voltage in the receiving coil. By connecting a load to the receiving coil, power is transferred.

Inductive charging vs. resonant inductive coupling

Inductive charging is often associated with resonant inductive coupling. If the transmitter and receiver coils are close together and tightly coupled, efficient power transfer can be realised with ordinary inductive coupling. If the coils are further away from each other and are loosely coupled a resonant system is preferred. A resonant system enhances power transfer significantly.

In a resonant system, power is transferred between resonant circuits that are driven at the resonance frequency. Additional components – called capacitors – are added to compensate for the effects of stray and or magnetizing inductances of the wireless power transformer which consists out of the transmitter and the receiver coils.

Alternative ways to transfer power wirelessly

Next to inductive power transfer via magnetic induction, there are other technologies to transfer power wirelessly. The best known are RF (far field), ultrasound and power transfer through light (e.g. laser). These technologies have been presented and demonstrated frequently for many years already on the internet and at fairs as a wireless power solution. However no commercial products made it to the market today. Issues blocking market introduction are mostly related to safety issues, like the maximum exposure to electromagnetic fields according to the International Commission on Non-Ionizing Radiation Protection ( ICNIRP), Electro-magnetic Interference (EMC) or a simple lack of efficiency in wireless power transfer.

Qi wireless power standard

In 2008 the Wireless Power Consortium (WPC) was founded and they introduced the first wireless power “Qi” standard. Today there are over 220 companies member of the Wireless Power Consortium, including ZENS. The Qi standard is the most widely adopted global wireless power standard. More than 1300 Qi types of devices, including phones, are in the market which can be charged wirelessly. The consortium continuously defines new parts of, maintains and develops the Qi standard.

The name “Qi” comes from the Asian philosophy and means vital energy, an intangible flow of power. If a mobile device carries the Qi logo it is an official tested and registered device meeting all the requirements imposed by the Qi standard. The benefit of having such a standard is that any mobile device can be charged on any Qi charger. This is not only convenient at home but for sure also in public spaces. New chargers must be backwards compatible meaning that also older types of phones still work with a new charger.

Qi developments

The first Qi standard was the low power standard up to 5W, introduced by the WPC in 2008. The 15W standard, enabling fast charging of smartphones and charging of tablets, has been introduced in 2015. The standards of the 60W – 200W and the 200W – 2400W power ranges are still in development.

About ZENS | your wireless power expert

ZENS is your innovative wireless charging expert. From the heart of one of Europe’s most prominent high-tech centres, we develop state-of-the-art wireless charging solutions that aim to improve quality of life. ZENS is not limited to Qi only. As a wireless charging expert we offer customized wireless power designs for you as well. Check out our wireless power business solutions, wireless chargers for consumers or if you’re thinking about applying the technology to your business environment, do not hesitate to contact us.

Cars and trucks house hundreds of tiny screws. You may find that sometimes as you loosen a screw, it can be virtually impossible to remove it unless the screwdriver is magnetic. Although you can buy a dedicated magnetic screwdriver, you might not have access to one when you need it. Fortunately, you can make your own regular screwdriver magnetic by using a few basic components.

Step 1

Strip 1 inch of shielding off each end of the wire using the wire strippers. Pop the hood of the vehicle and locate the battery. If you have a loose car battery available, place it on a surface where you can work on it.

Step 2

Wrap the wire tightly around the metal shaft of the screwdriver, leaving approximately 1 foot of wire at each end.

Step 3

Hold one end of the wire to the positive terminal. Hold the other end your hand, making sure to hold on to the insulated part. Quickly tap the wire against the negative terminal for a fraction of a second. Repeat at least 5 times.

Remove the wire from the screwdriver and test to make sure that it is magnetic.

Warning

• Do not keep the wire touching the negative terminal for more than an instant. Do not touch the bare wire while current is running through it.

Items you will need

• 2 feet of insulated 18-gauge wire Screwdriver Wire strippers

This article was written by the It Still Works team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information. To submit your questions or ideas, or to simply learn more about It Still Works, contact us.

Years after it first appeared, wireless charging has finally arrived on the iPhone—but what is this magical charging method that’s been on other big phones for a couple of years now? And is it really all that superior to just plugging your phone into the wall every night? Here’s what you need to know about wireless charging, and the kit you need to make it work.

How wireless charging works

The key to wireless (or inductive) charging are electromagnetic fields, used to transfer energy from one place (a charging mat) to another (your phone) through the magic of electromagnetic induction .

Essentially you’ve got two physical coils, one which converts energy into an electromagnetic field that can travel wirelessly, and one which converts that floating field back into energy again—the two coils form a transformer . That’s why the wireless charging cat was out of the bag as soon as a coil was spotted in leaked schematics for the iPhone 8 .

If your phone doesn’t support wireless charging out of the box, you can often get a case or adapter that takes care of all of the necessary power transfer processes and feeds the juice straight into the handset—you don’t have to miss out on the wireless charging. Considering wireless charging pads are usually optional extras anyway, you can just add another adapter to your basket.

We’ll get on to standards in a moment, but in addition to the popular magnetic induction method we’ve explained above, you also need to know about the magnetic resonance method—in essence, it’s not all that different, but it increases charging distances , makes it easier for multiple devices to charge up at once on the same charger, and can work through more, and thicker, materials.

For most smartphone owners, that’s as much as you’ll need to know, but pay attention to the quoted voltage of your phone and your charger—the charging speed will be limited by whichever is the slower, and it’ll usually be significantly slower than plugging your phone into a wall. That said, you should also bear in mind that these specs and standards are improving all the time, as the technology gets more efficient, and the prices of the required components come down.

Wireless charging standards

As we said at the outset, wireless charging has been with us for years, in everything from electric toothbrushes to the Nokia Lumia 820 from 2012. Of course, tech wouldn’t be tech without a few differing and incompatible standards to stay abreast of.

The big one, as far as wireless charging goes—the one supported by most phones and the new iPhones —is Qi (pronounced “chee”) charging. Qi is developed by the Wireless Power Consortium , and its 247 members include the likes of Apple, Google, Samsung and just about every other big name in electronics manufacturing. The latest phones from Apple, Samsung and LG all have Qi built in.

The other main contender is AirFuel , formed from a partnership between the Alliance for Wireless Power and the Power Matters Alliance. Like Qi, the standard supports both magnetic induction and magnetic resonance, but its implemented in a slightly different way, so the two technologies aren’t compatible with each other (you can’t charge up a Qi-enabled phone on a AirFuel-enabled mat).

AirFuel (previously known as Powermat) isn’t as widespread as Qi, but some major handsets support it (the Galaxy S8 family can work with both Qi and AirFuel), and it’s the wireless charging technology that Starbucks has installed at its outlets—although the coffee seller is now adding Qi support as well.

As long as you buy accessories using the same standard as your smartphone, you can’t go far wrong, but if you’re wondering why you’ve put your iPhone X down on an AirFuel charging pad at Starbucks and it’s not working, now you know.

What you need for wireless charging

Despite the complex technologies underpinning wireless charging, and the competing standards fighting it out for market share, it’s not that difficult to figure out what you need to set up your own wireless charging solution—check the standard supported by your phone, get an accessory to match, and you’re away.

Plenty of phones now support the Qi standard , including newer models from LG and Samsung, and the new iPhones. Meanwhile, AirFuel wireless charging is available in this year’s LG G6 , all the Samsung Galaxy phones of recent years, and some less well-known models . If you’re desperate to use the technology, you can invest in a power ring that slots into the bottom of your phone and enables it to be charged up by any AirFuel charger.

It’s not quite so essential to buy official accessories from the same company that makes your phone when it comes to wireless charging: All Qi-enabled chargers will work with all Qi-enabled handsets, for example, so take your pick. As we mentioned earlier though, double-check the maximum power ratings—you really want your phone and charger to match, otherwise one will be holding the other back.

Apple being Apple, it’s bringing out its own bespoke charging mat called AirPower , which is based on Qi technology. It will charge up any 2017 iPhone, your AirPods (as long as they’re in Apple’s official charging case), and the Apple Watch Series 3 (though not the Series 1 or 2). It’s not clear exactly how AirPower builds on Qi—it has some special features like multiple (Apple) device support, and charging status indicators across all your devices—but you can also charge your iPhone 8, iPhone 8 Plus, and iPhone X on any standard Qi-enabled mat if you prefer.

Samsung, for its part, also offers a “fast charging” wireless pad based around Qi technology—it charges up compatible Samsung phones faster in return for running hotter, something that’s mitigated with an integrated fan. With Samsung’s handsets supporting Qi and AirFuel tech too, you’ve got plenty of choice.

You might have heard about the launch of latest smartphones like Nokia Lumia 920 in the market. The latest smartphones use the wireless charging technology for charging the battery. This is a new avatar of old electrical theory that existed years ago. In this article, I shall discuss about the nature of wireless charging, how it works and its latest developments. Please read on.

What is Wireless charging

Wireless charging is called inductive charging as it uses the principle that electricity is induced from another electrical field or magnetic field of another object, if the electrical / magnetic fields are disturbed or cut. In this technology, a charging station is used for battery charging. Electricity is used for creating an electromagnetic field by using an induction coil in the charging station. There is also a secondary induction coil which transfers the electromagnetic field in to electrical energy for charging battery. This is the principle followed in most of the electrical transformers.

How Wireless charging works

Nowadays, your smartphone with Wireless charging mechanism comes with a charging pad or charging cover. Actually these charging pad or cover contains lots of smaller coils which will emit electromagnetic radiation when connected with electricity. The smaller coils are designed such that the alternate coils are charged with your alternate form of current viz., Alternate Current. These alternate charging of minute coils and corresponding emission of electromagnetic radiation poses different electromagnetic fields at different points of time.

Your smartphone also contains few minute but stationary coils and when your smartphone is placed on the charging pads or covers, the coil in your smartphone actually acts as if cutting the electromagnetic fields created at various points by your charging pad or cover. Thus cutting of electromagnetic field by the coils of your smartphone induces current or electricity. The smaller amount of electricity thus created is transmitted to the battery of your smartphone, keeping it live. These mini doses of electricity actually accumulates in the battery of your smartphone and therefore, the battery gets fully charged depending on the time interval at which these charging pads or covers are being used for charging.