iPad充電器給iPhone充電：安全

iPhone充(chong)電器給iPad充(chong)電：難說

iPhone充電(dian)器給iPhone充電(dian)（完全放電(dian)）

iPad充(chong)電(dian)器給iPhone4s充(chong)電(dian)（完全放電(dian)）

在蘋(pin)果(guo)官網(wang)的技術支持區里有這樣一(yi)段說明：iPad USB電源適(shi)配器是一(yi)個10W的充電器。雖然此iPad 10W USB電源適(shi)配器設計為供iPad使用，但是您(nin)仍可通過其對(dui)所有iPhone和iPod機型充電。

但對 “果粉”來(lai)說，有條微博讓(rang)人很(hen)糾結：請不要用(yong)iPad的(de)(de)(de)充(chong)(chong)電(dian)器為iPhone充(chong)(chong)電(dian)，雖然(ran)它們看起(qi)來(lai)長得一樣(yang)，兩者的(de)(de)(de)充(chong)(chong)電(dian)電(dian)壓也都是5V，但是iPhone充(chong)(chong)電(dian)的(de)(de)(de)額(e)定電(dian)流是1A，而(er)iPad卻是2.1A……混用(yong)充(chong)(chong)電(dian)器的(de)(de)(de)后果是既傷iPhone又傷iPad充(chong)(chong)電(dian)器”。

iPad和iPhone充電器到底能不能混用？口(kou)說無(wu)憑，實(shi)驗為證，《好奇實(shi)驗室》為你實(shi)測。

實驗對象(xiang)：兩臺(tai)iPad、一臺(tai)iPad2、一臺(tai)iPhone4、一臺(tai)iPhone4s

中國(guo)計量學院(yuan)機(ji)電(dian)工程學院(yuan)的(de)蔡慧老師說(shuo)，iPad充電(dian)器(qi)的(de)功(gong)率(lv)10W，是指電(dian)源的(de)最大(da)輸出(chu)(chu)功(gong)率(lv)，但實際(ji)(ji)輸出(chu)(chu)功(gong)率(lv)要取決(jue)于所(suo)接(jie)的(de)負載；iPad和iPhone的(de)充電(dian)器(qi)的(de)額(e)定電(dian)壓都(dou)是5V，只要實際(ji)(ji)電(dian)流不超過額(e)定電(dian)流（即iPhone1A，iPad2.1A），也(ye)不會(hui)對充電(dian)設(she)備造(zao)成傷(shang)害。

iPad和(he)(he)iPhone的充(chong)電(dian)(dian)器連(lian)接線(xian)(xian)(xian)(xian)都是(shi)一樣的，我們把它剪斷，里面有(you)(you)紅(hong)黑(hei)白(bai)綠(lv)四(si)條線(xian)(xian)(xian)(xian)，經檢測，紅(hong)線(xian)(xian)(xian)(xian)是(shi)電(dian)(dian)源(yuan)線(xian)(xian)(xian)(xian)，黑(hei)線(xian)(xian)(xian)(xian)是(shi)地線(xian)(xian)(xian)(xian)，當連(lian)接線(xian)(xian)(xian)(xian)和(he)(he)iPad充(chong)電(dian)(dian)器相連(lian)時，在白(bai)線(xian)(xian)(xian)(xian)和(he)(he)綠(lv)線(xian)(xian)(xian)(xian)上分別檢測到了2V和(he)(he)2.7V電(dian)(dian)壓，而當連(lian)接線(xian)(xian)(xian)(xian)和(he)(he)iPhone充(chong)電(dian)(dian)器連(lian)接時，白(bai)、綠(lv)兩條線(xian)(xian)(xian)(xian)上沒(mei)有(you)(you)測到電(dian)(dian)壓。

“白(bai)、綠兩(liang)(liang)條(tiao)線(xian)是信號線(xian)，當(dang)iPad或iPhone接上充電(dian)(dian)器時(shi)，通過(guo)這兩(liang)(liang)條(tiao)線(xian)可以區(qu)分當(dang)前使用的是哪(na)種充電(dian)(dian)器，能對負載做出(chu)相應的調整。”蔡慧(hui)老師說。

我們先用萬能表(biao)對各種充電方式(shi)進行(xing)檢測。

iPad充電器（單(dan)位：A） iPhone充電器（單(dan)位：A）

50%電量的(de)iPadA 1.5 0.48

60%電(dian)量(liang)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%電量的iPhone4s 0.88 0.9

從檢測結果看(kan)，iPad充(chong)電器給iPhone充(chong)電時，實際(ji)電流(liu)都低于(yu)1A，而(er)用iPhone充(chong)電器給iPad充(chong)電時，iPadA和iPad2顯(xian)示(shi)“沒有充(chong)電”，顯(xian)示(shi)“正在充(chong)電”字樣的iPadB的實際(ji)電流(liu)偏大，超過了1A。

“iPadB里(li)的(de)一些系(xi)統軟件可(ke)能被更改(gai)了，導致這樣(yang)的(de)問(wen)題出現，用iPhone充(chong)電(dian)器(qi)充(chong)電(dian)時(shi)，iPad是不會(hui)有(you)損傷(shang)(shang)的(de)，因為電(dian)流(liu)小于額定電(dian)流(liu)，但對充(chong)電(dian)器(qi)會(hui)有(you)損傷(shang)(shang)，時(shi)間一長，充(chong)電(dian)器(qi)就會(hui)壞掉。”

我們注意到，不同電(dian)(dian)(dian)量的(de)設(she)備，充電(dian)(dian)(dian)的(de)實際電(dian)(dian)(dian)流(liu)大(da)小也是(shi)不一樣的(de)，蔡老師解(jie)釋說，這是(shi)因為(wei)智能電(dian)(dian)(dian)池在充電(dian)(dian)(dian)過程中，為(wei)了(le)保持電(dian)(dian)(dian)池不受傷(shang)害，所以電(dian)(dian)(dian)流(liu)的(de)大(da)小是(shi)會發生改(gai)變的(de)。

為(wei)更(geng)詳細(xi)地了(le)(le)解整(zheng)(zheng)個充電過程(cheng)，我(wo)們決定把iPad和iPhone完全放(fang)電到0%后(hou)，再進行充電，并用萬能表連接(jie)電腦來(lai)記錄整(zheng)(zheng)個充電過程(cheng)――由于時間(jian)關系(xi)，我(wo)們選擇了(le)(le)iPad2和iPhoe4s來(lai)進行實驗。

時間(jian) 實際電流（單(dan)位(wei)：A）

iPhone4s充(chong)電器充(chong)iPhone4s 約4小時(shi) 0.8以下

iPhone4s充(chong)電器充(chong)iPad2 約14小時 0.5以下(xia)

iPad2充(chong)電器(qi)充(chong)iPhone4s 約(yue)3小(xiao)時 0.83以(yi)下

iPad2充電(dian)器(qi)充iPad2 約9小時(shi) 1以下

從檢測結果看，iPad充(chong)(chong)電(dian)(dian)(dian)器(qi)給(gei)iPhone4s充(chong)(chong)電(dian)(dian)(dian)時(shi)，電(dian)(dian)(dian)流(liu)一直(zhi)都在額定電(dian)(dian)(dian)流(liu)以下，比(bi)用(yong)iPhone充(chong)(chong)電(dian)(dian)(dian)器(qi)充(chong)(chong)電(dian)(dian)(dian)的電(dian)(dian)(dian)流(liu)稍大(da)，速度也稍快一些；用(yong)iPhone充(chong)(chong)電(dian)(dian)(dian)器(qi)給(gei)iPad充(chong)(chong)電(dian)(dian)(dian)時(shi)，雖(sui)然iPad上沒有顯示充(chong)(chong)電(dian)(dian)(dian)，但實際上一直(zhi)在充(chong)(chong)電(dian)(dian)(dian)，只是需要的時(shi)間(jian)相當長。

但不管哪(na)種方式充(chong)電(dian)(dian)(dian)，整個充(chong)電(dian)(dian)(dian)過(guo)程中的電(dian)(dian)(dian)流(liu)都是先(xian)低(di)后高，然(ran)后慢慢下降(jiang)，當電(dian)(dian)(dian)量到(dao)90%左右時，電(dian)(dian)(dian)流(liu)會越來(lai)越小(xiao)。

“如果(guo)開(kai)始充(chong)電(dian)(dian)(dian)時(shi)電(dian)(dian)(dian)池電(dian)(dian)(dian)量很低，那么必須(xu)用小電(dian)(dian)(dian)流(liu)開(kai)始充(chong)電(dian)(dian)(dian)，小電(dian)(dian)(dian)流(liu)充(chong)電(dian)(dian)(dian)是(shi)為了保護電(dian)(dian)(dian)池，避(bi)免大電(dian)(dian)(dian)流(liu)沖擊給電(dian)(dian)(dian)池內(nei)部結構帶來損(sun)害(hai)；而當(dang)電(dian)(dian)(dian)池電(dian)(dian)(dian)壓達(da)到或接近充(chong)滿電(dian)(dian)(dian)壓時(shi)，則要(yao)開(kai)始轉入恒壓充(chong)電(dian)(dian)(dian)，如果(guo)不轉入小電(dian)(dian)(dian)流(liu)充(chong)電(dian)(dian)(dian)，就可能(neng)導致電(dian)(dian)(dian)壓過高(gao)，有(you)過充(chong)的(de)危險，也是(shi)對電(dian)(dian)(dian)池有(you)害(hai)的(de)。”蔡老師說。

但即使是用iPad充電器給(gei)iPad充電，實際電流(liu)也沒(mei)有大于(yu)1A，這是為什么(me)呢(ni)？

蔡老(lao)師說，iPad和iPhone會(hui)根據電(dian)池(chi)(chi)的(de)余(yu)量(liang)來(lai)選擇充電(dian)方(fang)案，當(dang)(dang)電(dian)池(chi)(chi)完全(quan)耗光(guang)時(shi)，就相當(dang)(dang)于一個餓了很長時(shi)間的(de)人，不能(neng)一下子進食太多，而應該一點一點慢慢吃(chi)，所(suo)以完全(quan)放電(dian)后充電(dian)，比有余(yu)電(dian)時(shi)充電(dian)的(de)電(dian)量(liang)更(geng)小一些，時(shi)間也(ye)更(geng)長一些。