iPad充電器給(gei)iPhone充電：安全

iPhone充電(dian)器給iPad充電(dian)：難說

iPhone充(chong)電(dian)(dian)器(qi)給iPhone充(chong)電(dian)(dian)（完(wan)全放電(dian)(dian)）

iPad充電(dian)(dian)器給iPhone4s充電(dian)(dian)（完(wan)全放電(dian)(dian)）

在蘋果(guo)官網(wang)的(de)技術支持區(qu)里有這(zhe)樣一(yi)段說明(ming)：iPad USB電源適(shi)配器是(shi)一(yi)個10W的(de)充(chong)電器。雖(sui)然此iPad 10W USB電源適(shi)配器設計為供iPad使用(yong)，但是(shi)您仍(reng)可通過其對所有iPhone和iPod機型充(chong)電。

但(dan)對 “果(guo)粉”來(lai)說，有條微博讓(rang)人很糾結：請不(bu)要用iPad的(de)充(chong)(chong)(chong)電器為iPhone充(chong)(chong)(chong)電，雖然它(ta)們(men)看起(qi)來(lai)長得一樣，兩者(zhe)的(de)充(chong)(chong)(chong)電電壓也都是(shi)(shi)5V，但(dan)是(shi)(shi)iPhone充(chong)(chong)(chong)電的(de)額定電流是(shi)(shi)1A，而iPad卻是(shi)(shi)2.1A……混用充(chong)(chong)(chong)電器的(de)后果(guo)是(shi)(shi)既傷iPhone又(you)傷iPad充(chong)(chong)(chong)電器”。

iPad和iPhone充電(dian)器(qi)到底能(neng)不(bu)能(neng)混用？口說無(wu)憑(ping)，實(shi)驗為證，《好(hao)奇實(shi)驗室》為你實(shi)測。

實驗對象：兩(liang)臺(tai)iPad、一臺(tai)iPad2、一臺(tai)iPhone4、一臺(tai)iPhone4s

中國計量學院(yuan)機電(dian)(dian)(dian)(dian)工程學院(yuan)的(de)蔡慧老師說，iPad充電(dian)(dian)(dian)(dian)器的(de)功率(lv)10W，是指電(dian)(dian)(dian)(dian)源(yuan)的(de)最大輸(shu)(shu)出(chu)功率(lv)，但實(shi)際輸(shu)(shu)出(chu)功率(lv)要取決于所接的(de)負載；iPad和iPhone的(de)充電(dian)(dian)(dian)(dian)器的(de)額(e)定電(dian)(dian)(dian)(dian)壓都是5V，只要實(shi)際電(dian)(dian)(dian)(dian)流(liu)不(bu)超(chao)過額(e)定電(dian)(dian)(dian)(dian)流(liu)（即(ji)iPhone1A，iPad2.1A），也(ye)不(bu)會對充電(dian)(dian)(dian)(dian)設備造(zao)成傷害。

iPad和(he)(he)(he)iPhone的充(chong)電(dian)(dian)(dian)器(qi)連接(jie)(jie)線(xian)(xian)都是(shi)(shi)一樣(yang)的，我們把(ba)它剪(jian)斷，里(li)面(mian)有紅(hong)黑(hei)白(bai)綠(lv)四條(tiao)線(xian)(xian)，經檢測，紅(hong)線(xian)(xian)是(shi)(shi)電(dian)(dian)(dian)源(yuan)線(xian)(xian)，黑(hei)線(xian)(xian)是(shi)(shi)地線(xian)(xian)，當連接(jie)(jie)線(xian)(xian)和(he)(he)(he)iPad充(chong)電(dian)(dian)(dian)器(qi)相連時，在白(bai)線(xian)(xian)和(he)(he)(he)綠(lv)線(xian)(xian)上分(fen)別檢測到(dao)了2V和(he)(he)(he)2.7V電(dian)(dian)(dian)壓，而(er)當連接(jie)(jie)線(xian)(xian)和(he)(he)(he)iPhone充(chong)電(dian)(dian)(dian)器(qi)連接(jie)(jie)時，白(bai)、綠(lv)兩條(tiao)線(xian)(xian)上沒有測到(dao)電(dian)(dian)(dian)壓。

“白、綠兩(liang)條(tiao)線(xian)是信號線(xian)，當iPad或iPhone接上(shang)充電(dian)器時，通過這兩(liang)條(tiao)線(xian)可以區分當前使用(yong)的(de)是哪種充電(dian)器，能(neng)對負載做出(chu)相(xiang)應的(de)調整。”蔡慧老(lao)師說。

我們先用萬(wan)能表(biao)對各種充電方式進行檢測。

iPad充電器(qi)（單位：A） iPhone充電器(qi)（單位：A）

50%電量的iPadA 1.5 0.48

60%電量的iPadB 1.5 1.26

70%電量的iPad2 1.4 0.48

39%電量的iPhone4 0.98 0.45

40%電量(liang)的(de)iPhone4s 0.88 0.9

從檢(jian)測(ce)結果看(kan)，iPad充(chong)電(dian)器給iPhone充(chong)電(dian)時，實(shi)際(ji)電(dian)流都低于1A，而(er)用iPhone充(chong)電(dian)器給iPad充(chong)電(dian)時，iPadA和(he)iPad2顯(xian)示“沒有(you)充(chong)電(dian)”，顯(xian)示“正(zheng)在充(chong)電(dian)”字樣的iPadB的實(shi)際(ji)電(dian)流偏大，超過了(le)1A。

“iPadB里的(de)一些(xie)系統(tong)軟(ruan)件(jian)可能被更改了，導致這樣的(de)問題出現，用iPhone充(chong)電器(qi)充(chong)電時，iPad是不會(hui)有(you)損(sun)傷(shang)的(de)，因為電流小于(yu)額定電流，但對充(chong)電器(qi)會(hui)有(you)損(sun)傷(shang)，時間一長，充(chong)電器(qi)就(jiu)會(hui)壞掉。”

我(wo)們注意到，不(bu)同(tong)電(dian)(dian)量的設備，充(chong)電(dian)(dian)的實際電(dian)(dian)流(liu)(liu)大小也是(shi)(shi)不(bu)一樣的，蔡老師解釋(shi)說，這(zhe)是(shi)(shi)因為智(zhi)能電(dian)(dian)池在充(chong)電(dian)(dian)過程中，為了保持電(dian)(dian)池不(bu)受傷害，所以電(dian)(dian)流(liu)(liu)的大小是(shi)(shi)會發(fa)生(sheng)改變(bian)的。

為更(geng)詳細地了解整個(ge)(ge)充(chong)電(dian)(dian)過(guo)程(cheng)，我(wo)們(men)決定把iPad和iPhone完(wan)全放電(dian)(dian)到0%后，再進行(xing)充(chong)電(dian)(dian)，并(bing)用萬能表(biao)連(lian)接(jie)電(dian)(dian)腦來記錄整個(ge)(ge)充(chong)電(dian)(dian)過(guo)程(cheng)――由于時間關系(xi)，我(wo)們(men)選擇了iPad2和iPhoe4s來進行(xing)實驗。

時(shi)間 實際電流（單位：A）

iPhone4s充電器充iPhone4s 約4小時 0.8以下

iPhone4s充(chong)電器充(chong)iPad2 約14小時 0.5以(yi)下

iPad2充電器充iPhone4s 約3小時(shi) 0.83以下(xia)

iPad2充(chong)電器充(chong)iPad2 約(yue)9小時 1以下

從檢測結(jie)果看，iPad充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器給(gei)iPhone4s充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)時(shi)(shi)，電(dian)(dian)(dian)(dian)流一直(zhi)都在額定電(dian)(dian)(dian)(dian)流以下，比用(yong)iPhone充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)的電(dian)(dian)(dian)(dian)流稍大，速度也稍快一些；用(yong)iPhone充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器給(gei)iPad充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)時(shi)(shi)，雖然iPad上(shang)沒有顯示充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)，但(dan)實際上(shang)一直(zhi)在充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)，只(zhi)是需要的時(shi)(shi)間相當長。

但不管哪(na)種方式充電(dian)(dian)(dian)，整個充電(dian)(dian)(dian)過程中的電(dian)(dian)(dian)流都(dou)是先(xian)低后高(gao)，然后慢慢下(xia)降，當電(dian)(dian)(dian)量到90%左右(you)時，電(dian)(dian)(dian)流會越(yue)來越(yue)小。

“如(ru)果開始充(chong)(chong)電(dian)(dian)(dian)時電(dian)(dian)(dian)池電(dian)(dian)(dian)量很(hen)低(di)，那(nei)么必須用小(xiao)電(dian)(dian)(dian)流(liu)(liu)開始充(chong)(chong)電(dian)(dian)(dian)，小(xiao)電(dian)(dian)(dian)流(liu)(liu)充(chong)(chong)電(dian)(dian)(dian)是為了保護(hu)電(dian)(dian)(dian)池，避免(mian)大電(dian)(dian)(dian)流(liu)(liu)沖擊給電(dian)(dian)(dian)池內部(bu)結構帶(dai)來損害；而(er)當(dang)電(dian)(dian)(dian)池電(dian)(dian)(dian)壓(ya)達到或接近充(chong)(chong)滿電(dian)(dian)(dian)壓(ya)時，則要開始轉入恒(heng)壓(ya)充(chong)(chong)電(dian)(dian)(dian)，如(ru)果不轉入小(xiao)電(dian)(dian)(dian)流(liu)(liu)充(chong)(chong)電(dian)(dian)(dian)，就可能導致(zhi)電(dian)(dian)(dian)壓(ya)過(guo)高，有過(guo)充(chong)(chong)的危險(xian)，也是對電(dian)(dian)(dian)池有害的。”蔡老師說。

但即使是(shi)用(yong)iPad充電(dian)(dian)器給iPad充電(dian)(dian)，實際電(dian)(dian)流也沒有大于1A，這是(shi)為什(shen)么呢(ni)？

蔡老(lao)師說(shuo)，iPad和(he)iPhone會根據電池(chi)的余(yu)量來選擇充(chong)(chong)電方案，當(dang)電池(chi)完(wan)全耗光時(shi)，就相當(dang)于一(yi)個(ge)餓了很(hen)長時(shi)間的人，不能一(yi)下子進食太多，而應(ying)該(gai)一(yi)點一(yi)點慢慢吃，所以完(wan)全放電后充(chong)(chong)電，比有(you)余(yu)電時(shi)充(chong)(chong)電的電量更(geng)小一(yi)些，時(shi)間也更(geng)長一(yi)些。