Look, you cannot avoid basic principles of physics. It would take an increasingly large amount of power to wirelessly charge any device beyond a fraction of an inch. Wireless power for the Watch may make more sense, but still...
There have been tests done over longer ranges with magnetic resonance:
"The team conducted several experiments and achieved promising results: for instance, under the operation of 20 kHz, the maximum output power was 1,403 W at a 3-meter distance, 471 W at 4-meter, and 209 W at 5-meter. For 100 W of electric power transfer, the overall system power efficiency was 36.9% at 3 meters, 18.7% at 4 meters, and 9.2% at 5 meters.
"With DCRS," Professor Rim said, "a large LED TV as well as three 40 W-fans can be powered from a 5-meter distance.""
The beam won't be omnidirectional so won't falloff with the square of the distance. It can work in any direction but they'd focus the transmission at the device. It wastes energy but we're talking about mobile devices with 6-7 Wh batteries. If they manage average 20% efficiency in a room, charging a 7Wh battery would waste 28Wh or the same as a light bulb running for half an hour and this is only while a device is needing charged. Typically, it wouldn't need more than 50% of its battery topped up so a light bulb for 15 minutes.
This is mainly beneficial in places like offices, airports, taxis, planes etc where its not feasible to have dozens of people huddled round charging sockets and where people aren't likely to have their charging plugs with them. The US Navy has been testing wireless charging for underwater use as it means no exposed contacts that can short out with water. It would be safer to charge things like shavers, electric toothbrushes and to power lighting in the bathroom this way.
I don't think the problem in getting this to market will be the range limitation but rather shrinking the antennas to fit into consumer products while maintaining the efficiency. Wifi didn't have the performance we have today, it started around 2-11Mbps and the iBook was one of the first consumer products to have it in 1999. We now have gigabit wifi. As soon as the technology hits the market, companies will be trying to come up with more efficient solutions. It may work best attached to lighting as it's centrally located in a room.
The concerns about energy efficiency will become irrelevant when we are primarily using renewable energy sources. You can use as much power as you want.
You'd also be able to microwave a burrito by holding it next to your phone. This isn't gonna happen. It's impractical and wasteful. Multiply that huge inefficiency over hundreds of millions of devices and suddenly Apple would be on the "horrible offenders" list of every environmental organization on Earth.
I hope iPhone 8 has long distance wireless charging. They could have added inductive charging years ago. Usually apple waits with a particular feature so they can add new and better technology. Inductive is old school.
It may do old-school, but I much prefer MagSafe over a non-magnetic solution.
How exactly will MagSafe for Lightning work without making the plug considerably larger?
Why does the phone need Lightning? My MagSafe example was referring to magnetic connections in general. The question is, how small can the surface area of a magnetic connection actually be for charging only.
Smart connector on the iPadPro can charge those devices. So that connector must go close to being able to safely handle charging needs of all Apple's Portables.
I hope iPhone 8 has long distance wireless charging. They could have added inductive charging years ago. Usually apple waits with a particular feature so they can add new and better technology. Inductive is old school.
It may do old-school, but I much prefer MagSafe over a non-magnetic solution.
How exactly will MagSafe for Lightning work without making the plug considerably larger?
Why does the phone need Lightning? My MagSafe example was referring to magnetic connections in general. The question is, how small can the surface area of a magnetic connection actually be for charging only.
What do you mean "why do a phone need Lightning." For data, of course. You can use WiFi, but you still need to have a physical data connection available on the device.
As Mattinoz points out, you can use a SmartConnector like on the iPad Pro and like what was rumoured for the iPhone 7 last year, but that's very different from your stated MagSafe connector.
I'll never buy an iPhone that has ONLY wireless charging. How do you charge it in the car? You'd need a charging unit in every location you wanted to charge the phone
I'll never buy an iPhone that has ONLY wireless charging. How do you charge it in the car? You'd need a charging unit in every location you wanted to charge the phone
A number of new cars offer wireless charging pads.
Look, you cannot avoid basic principles of physics. It would take an increasingly large amount of power to wirelessly charge any device beyond a fraction of an inch. Wireless power for the Watch may make more sense, but still...
There have been tests done over longer ranges with magnetic resonance:
"The team conducted several experiments and achieved promising results: for instance, under the operation of 20 kHz, the maximum output power was 1,403 W at a 3-meter distance, 471 W at 4-meter, and 209 W at 5-meter. For 100 W of electric power transfer, the overall system power efficiency was 36.9% at 3 meters, 18.7% at 4 meters, and 9.2% at 5 meters.
"With DCRS," Professor Rim said, "a large LED TV as well as three 40 W-fans can be powered from a 5-meter distance.""
The beam won't be omnidirectional so won't falloff with the square of the distance. It can work in any direction but they'd focus the transmission at the device. It wastes energy but we're talking about mobile devices with 6-7 Wh batteries. If they manage average 20% efficiency in a room, charging a 7Wh battery would waste 28Wh or the same as a light bulb running for half an hour and this is only while a device is needing charged. Typically, it wouldn't need more than 50% of its battery topped up so a light bulb for 15 minutes.
This is mainly beneficial in places like offices, airports, taxis, planes etc where its not feasible to have dozens of people huddled round charging sockets and where people aren't likely to have their charging plugs with them. The US Navy has been testing wireless charging for underwater use as it means no exposed contacts that can short out with water. It would be safer to charge things like shavers, electric toothbrushes and to power lighting in the bathroom this way.
I don't think the problem in getting this to market will be the range limitation but rather shrinking the antennas to fit into consumer products while maintaining the efficiency. Wifi didn't have the performance we have today, it started around 2-11Mbps and the iBook was one of the first consumer products to have it in 1999. We now have gigabit wifi. As soon as the technology hits the market, companies will be trying to come up with more efficient solutions. It may work best attached to lighting as it's centrally located in a room.
The concerns about energy efficiency will become irrelevant when we are primarily using renewable energy sources. You can use as much power as you want.
Wonder if through directionality and interference patterns (say full interference off target and max power in the target zone), they could focus much greater amount of power in one spot or region than otherwise would be safe to do (not hitting people crossing the beams). Such interference would need many sending antennas that can direct power precisely at one target from many directions in a coordinated way. Probably a bit too early for something like that.
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As Mattinoz points out, you can use a SmartConnector like on the iPad Pro and like what was rumoured for the iPhone 7 last year, but that's very different from your stated MagSafe connector.