????電磁感應充電技術推廣較慢的另一個原因，則是兩大陣營之間爆發(fā)的標準之爭。其一是電力事業(yè)聯(lián)盟（PMA），代表成員包括金霸王（Duracell）、寶潔（Procter & Gamble）、高通和WiTricity等。其二是無線充電聯(lián)盟（WPC），該聯(lián)盟支持一套叫做“Qi”的標準，日立（Hitachi）、宜家（IKEA）、威瑞森（Verizon）等都是它的成員。但有些公司同時加入了兩大陣營，比如微軟（Microsoft）和三星（Samsung）等。

????這兩大標準基本上使用的是相同的技術，但技術規(guī)格不同，導致企業(yè)在產品中嵌入無線充電技術時往往會因為標準問題傷腦筋。據WPC的市場開發(fā)副總裁約翰?珀爾澤表示，當前市場上63款手機支持Qi標準，包括諾基亞（Nokia）、谷歌（Google）和索尼（Sony）旗下的部分機型。同時谷歌的Nexus和LG旗下的部分機型則兼容Powerbat的充電標準。

????Powermat公司還計劃向星巴克的顧客免費發(fā)放能連接店內充電器的“無線充電環(huán)”。這種充電環(huán)有點像Powermat去年收購的芬蘭公司PowerKiss的產品，目前的計劃零售價還不到10美元。另外PMA今年二月與A4WP達成了一項支持其Rezence標準的協(xié)議，Rezence標準使用了另一種叫做“磁共振”的技術。

????兩大行業(yè)組織PMA和A4WP都認為，磁共振很有可能將成為無線充電技術的第二代標準，因為磁共振可以傳輸更多的電力，足以為廚房用具等用電量更大的設備充電。（WPC則表示它也正在開發(fā)自己的磁共振技術。）英特爾上月在臺北國際電腦展上展示的無線PC也正是使用了Rezence的標準。

????磁共振技術主要依賴電磁共振耦合原理，它會在每個線圈周圍形成一個能夠傳輸電力的磁場，不需要對線圈進行精確排列。另外它還可以隔著一段較小的距離進行無線充電（大概兩英寸），不需要讓設備與充電器直接接觸。因此你可以把充電板鑲嵌在桌子底下，而不是放在桌面上。

????磁共振技術的另一個優(yōu)點，是可以同時支持一臺以上設備充電。Rezence標準就利用了很多手機都具備的藍牙功能，來搜索能夠與手機兼容的充電器。目前這項技術還沒上市，但格拉吉斯基認為，使用Rezence標準的產品最早可能今年就會到店開售。他表示：“這項技術的障礙，只不過是如何讓行業(yè)里正確的選手采用這項技術，然后以一個合理的價格提供給消費者。”

????但是兩英寸的距離畢竟還是太短了。如果要是隔著一間屋子也能充電那該多好？這就是WiTricity公司正在努力的目標。WiTricity是2007年從麻省理工學院孵化出的一家公司，它一直致力于開發(fā)公司產品管理與營銷副總裁凱納姆?希達亞特所謂的“高振諧的無線電力傳輸”技術。

????想象一下，一名歌劇演員可以用她的高音震破玻璃，這就是這項技術的原理。希達亞特表示：“任何物體都有一定的共振頻率。”將一臺設備和另一臺接收設備調到相同的頻率，它們就會形成共振?！半娏χ粫鬏?shù)焦舱耦l率相同的設備上?！边@使得電力的輸送距離可以達到4英尺。希達亞特補充道：“憑借這一點開啟了很多可能性?！?/p>

????比如我們可以借此給車輛或者醫(yī)療設備進行無線充電。”希達亞特指出：“醫(yī)院里的電線是個大問題，因為你必須給每樣設備消毒?！?/p>

????這項技術也可以應用于軍事用途，比如執(zhí)行任務的機器人可以就地充電。另外它也可以使很多士兵不必再背負重達40磅的電池。另外深海中的潛艇也可以利用這項技術向艇外的傳感器充電，因為在深海中拉電線顯然是不安全的。

????目前，無線充電技術的標準大戰(zhàn)還在繼續(xù)，無線充電技術本身也仍然是個新鮮事物，但這種局面不會永遠持續(xù)下去。就像Wi-Fi已經成為電腦之間交換數(shù)據的標準協(xié)議一樣，很快也將會有一種無線充電標準勝出，成為通用標準。直到那時，我們才將真正見證無線充電技術的潛力。

????希達亞特表示：“在四五年內，就將會有一種無線充電設備的通用標準。你將忘掉不同型號的充電器和連接線。你會找到一個無線充電熱點，而且它很好用?！保ㄘ敻恢形木W）

????譯者：樸成奎

????Another reason for the technology’s slow adoption? A good old-fashioned standards war between industry groups. The Power Matters Alliance, or PMA, backs one type of induction standard and counts Duracell, Procter & Gamble, Qualcomm, and WiTricity as members. The Wireless Power Consortium, or WPC, backs an induction standard called Qi (pronounced chee) and counts Hitachi, IKEA and Verizon as members. Some companies, such as Microsoft and Samsung, are members of both groups.

????The two standards use what is essentially the same technology but apply it with different specifications, creating problems for the companies that must embed the technology in their products. According to John Perzow, vice president of market development for WPC, 63 phones on the market today support the Qi standard, including those from Nokia, Google, and Sony. Meanwhile, Google Nexus and LG phones, among others, will have Powermat compatibility built into them.

????To up the ante, Powermat has plans to give away free “charging rings,” similar to those made by the Finnish firm PowerKiss it acquired last year, to Starbucks customers to encourage them to use in-store chargers. (It plans to sell them at retail for less than $10.) Meanwhile, the PMA struck a deal with A4WP in February to support its Rezence standard, which uses another kind of wireless charging technology called magnetic resonance.

????Both industry groups look to magnetic resonance technology as the likely second-generation standard for wireless charging, thanks to its ability to transfer larger quantities of energy and therefore support larger devices such as kitchen appliances. (The WPC says it is working on its own version of the tech.) The wireless PC that Intel demonstrated at Computex last month—you can see it in a video here—uses the Rezence standard.

????Magnetic resonance technology relies on resonant magnetic coupling, which creates a magnetic field around each coil that transfers power without having to align coils precisely. It can charge a device across small distances (about two inches) rather than requiring near-direct contact—a table can be retrofit with a charging pad attached underneath it instead of embedded in its surface.

????Magnetic resonance also allows more than one device to be charged at the same time. The Rezence standard uses the Bluetooth connection already present in many mobile electronics to detect the presence of a compatible charger. The technology is not yet on the market, but Grajski anticipates products using Rezence could be seen in stores as soon as this year. “Some of the barriers are just getting the right players in industry to adopt the technology and make it available at a reasonable price,” he says.

????Still, two inches is two inches. What about beaming power across a room? That’s where WiTricity comes in. Born out of the Massachusetts Institute of Technology in 2007, the company continues to develop what Kaynam Hedayat, vice president of product management and marketing, calls “highly resonant wireless power transfer” technology.

????Imagine an opera singer who can break glass with her voice—that’s how the technology works, Hedayat says. “Objects have a certain frequency by which they start vibrating,” he says. Tune a receiver and a device to the same frequency and they begin communicating with each other. “The energy is only transferred to devices that are tuned to that frequency,” he says. This allows electricity to transfer over distances of up to four feet. “With that, a lot of possibilities open up,” he adds.

????Such as charging vehicles or medical equipment wirelessly. “Wires in hospitals are a big issue because you have to sterilize every device,” Hedayat says.

????Or use in military applications, where robots in the field can be recharged while in position. Wireless charging tech could also help soldiers cut down on the nearly 40 pounds of battery that many soldiers carry on their backs, Hedayat says. And charging sensors on submarines would enable battery charging in deep-sea conditions, where it’s unsafe to run wires.

????For now, the wireless charging standards war rages on, and the technology remains a novelty at best. But it can’t go on forever. Just as Wi-Fi became the standard protocol for wireless data exchange between computers, so shall one wireless charging standard emerge as the winner. Only then will we see what wireless charging is capable of.

????“In four or five years, there will be one standard for wirelessly charging devices,” Hedayat says. ” You will forget about different adapters and connecters. You will find a hotspot and it’s just going to work.”