iPad充電器給iPhone充電：安(an)全

iPhone充電器給iPad充電：難說

iPhone充(chong)電器(qi)給iPhone充(chong)電（完全放電）

iPad充電(dian)器給iPhone4s充電(dian)（完全放電(dian)）

在(zai)蘋果(guo)官網的(de)技術支持區里(li)有(you)這樣(yang)一(yi)段說明(ming)：iPad USB電(dian)(dian)源適配(pei)器(qi)是一(yi)個10W的(de)充電(dian)(dian)器(qi)。雖然此iPad 10W USB電(dian)(dian)源適配(pei)器(qi)設(she)計為供(gong)iPad使用(yong)，但是您仍可通(tong)過其對所有(you)iPhone和iPod機型充電(dian)(dian)。

但對 “果(guo)(guo)粉”來說，有條微博讓人(ren)很(hen)糾(jiu)結：請不要用(yong)(yong)iPad的(de)充(chong)電(dian)器為(wei)iPhone充(chong)電(dian)，雖(sui)然它(ta)們(men)看起來長得(de)一樣，兩者的(de)充(chong)電(dian)電(dian)壓也都是(shi)(shi)5V，但是(shi)(shi)iPhone充(chong)電(dian)的(de)額定電(dian)流是(shi)(shi)1A，而iPad卻是(shi)(shi)2.1A……混(hun)用(yong)(yong)充(chong)電(dian)器的(de)后果(guo)(guo)是(shi)(shi)既傷iPhone又傷iPad充(chong)電(dian)器”。

iPad和iPhone充電器到底能不能混用(yong)？口說(shuo)無憑，實(shi)驗為(wei)證，《好奇實(shi)驗室(shi)》為(wei)你實(shi)測。

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

中國計量學院機電工(gong)程學院的(de)蔡慧老師說，iPad充電器的(de)功率10W，是(shi)指電源(yuan)的(de)最大輸出功率，但實(shi)際輸出功率要(yao)(yao)取(qu)決于所接的(de)負載；iPad和iPhone的(de)充電器的(de)額(e)定(ding)電壓都是(shi)5V，只要(yao)(yao)實(shi)際電流(liu)不(bu)超過(guo)額(e)定(ding)電流(liu)（即iPhone1A，iPad2.1A），也不(bu)會對充電設備造成(cheng)傷害(hai)。

iPad和iPhone的充電(dian)(dian)器(qi)連(lian)接線(xian)都是(shi)(shi)一樣的，我們把它剪(jian)斷(duan)，里(li)面有紅黑白(bai)綠(lv)四(si)條線(xian)，經檢(jian)測，紅線(xian)是(shi)(shi)電(dian)(dian)源線(xian)，黑線(xian)是(shi)(shi)地線(xian)，當(dang)連(lian)接線(xian)和iPad充電(dian)(dian)器(qi)相連(lian)時，在白(bai)線(xian)和綠(lv)線(xian)上(shang)分別檢(jian)測到(dao)了2V和2.7V電(dian)(dian)壓，而當(dang)連(lian)接線(xian)和iPhone充電(dian)(dian)器(qi)連(lian)接時，白(bai)、綠(lv)兩條線(xian)上(shang)沒有測到(dao)電(dian)(dian)壓。

“白、綠(lv)兩條線是信(xin)號線，當iPad或iPhone接上充電器時，通過(guo)這兩條線可以(yi)區分(fen)當前使用的(de)是哪種充電器，能對負載做(zuo)出相應的(de)調(diao)整。”蔡慧老師(shi)說。

我們(men)先用萬(wan)能表對各種充(chong)電方(fang)式(shi)進行檢測。

iPad充(chong)電器（單位(wei)：A） iPhone充(chong)電器（單位(wei)：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(dian)量的iPhone4s 0.88 0.9

從檢(jian)測結果看，iPad充(chong)(chong)電(dian)器給(gei)iPhone充(chong)(chong)電(dian)時(shi)，實際電(dian)流(liu)都低于1A，而用iPhone充(chong)(chong)電(dian)器給(gei)iPad充(chong)(chong)電(dian)時(shi)，iPadA和iPad2顯示(shi)“沒有充(chong)(chong)電(dian)”，顯示(shi)“正在充(chong)(chong)電(dian)”字樣(yang)的iPadB的實際電(dian)流(liu)偏大，超過了(le)1A。

“iPadB里(li)的(de)一(yi)些系統軟件可能被更改了，導致這樣的(de)問題出現(xian)，用iPhone充(chong)電(dian)器(qi)充(chong)電(dian)時，iPad是不會有損傷(shang)的(de)，因為電(dian)流(liu)小于額定電(dian)流(liu)，但對(dui)充(chong)電(dian)器(qi)會有損傷(shang)，時間(jian)一(yi)長，充(chong)電(dian)器(qi)就會壞(huai)掉。”

我們注意到，不(bu)同電量的(de)(de)(de)設備(bei)，充電的(de)(de)(de)實際電流(liu)大(da)小也是不(bu)一樣(yang)的(de)(de)(de)，蔡老師解釋(shi)說，這是因為智能電池(chi)在充電過程(cheng)中，為了保持電池(chi)不(bu)受傷害，所(suo)以(yi)電流(liu)的(de)(de)(de)大(da)小是會發生改(gai)變的(de)(de)(de)。

為更(geng)詳細地了(le)解整(zheng)個充電過(guo)程，我們(men)決定(ding)把iPad和(he)iPhone完全放電到0%后(hou)，再進(jin)行充電，并用萬能表連接電腦來記錄整(zheng)個充電過(guo)程――由于時間關(guan)系，我們(men)選(xuan)擇了(le)iPad2和(he)iPhoe4s來進(jin)行實驗。

時間(jian) 實際電流（單位：A）

iPhone4s充電(dian)器充iPhone4s 約4小時 0.8以下

iPhone4s充電(dian)器充iPad2 約14小時(shi) 0.5以下

iPad2充電器充iPhone4s 約3小時 0.83以下

iPad2充電器充iPad2 約9小時 1以下

從檢測(ce)結果看，iPad充(chong)(chong)電(dian)(dian)(dian)器(qi)給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(kuai)一些；用(yong)iPhone充(chong)(chong)電(dian)(dian)(dian)器(qi)給iPad充(chong)(chong)電(dian)(dian)(dian)時(shi)，雖然iPad上(shang)沒有(you)顯示(shi)充(chong)(chong)電(dian)(dian)(dian)，但實際上(shang)一直(zhi)在充(chong)(chong)電(dian)(dian)(dian)，只是需要的時(shi)間相當長。

但(dan)不管哪種方式充(chong)電(dian)，整個充(chong)電(dian)過(guo)程(cheng)中的電(dian)流都是先低后高，然后慢(man)慢(man)下降，當電(dian)量到90%左右時，電(dian)流會越(yue)來越(yue)小。

“如果開始(shi)(shi)(shi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)時電(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)量很低，那么必須用小電(dian)(dian)(dian)(dian)(dian)流開始(shi)(shi)(shi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)，小電(dian)(dian)(dian)(dian)(dian)流充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)是為了保護電(dian)(dian)(dian)(dian)(dian)池，避免(mian)大電(dian)(dian)(dian)(dian)(dian)流沖擊給電(dian)(dian)(dian)(dian)(dian)池內部(bu)結構帶(dai)來損(sun)害(hai)；而當電(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)壓達到或(huo)接近充(chong)(chong)(chong)滿電(dian)(dian)(dian)(dian)(dian)壓時，則要開始(shi)(shi)(shi)轉入(ru)恒壓充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)，如果不轉入(ru)小電(dian)(dian)(dian)(dian)(dian)流充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)，就可(ke)能導(dao)致電(dian)(dian)(dian)(dian)(dian)壓過(guo)高，有(you)過(guo)充(chong)(chong)(chong)的(de)危險(xian)，也(ye)是對電(dian)(dian)(dian)(dian)(dian)池有(you)害(hai)的(de)。”蔡老師說。

但即(ji)使是用iPad充電器(qi)給iPad充電，實際電流也(ye)沒(mei)有大于1A，這是為什(shen)么呢？

蔡老(lao)師說，iPad和(he)iPhone會根據電池(chi)的(de)余量來選擇充電方案，當(dang)電池(chi)完全耗光時，就相(xiang)當(dang)于一(yi)個(ge)餓了很長時間(jian)(jian)的(de)人，不能(neng)一(yi)下子進食太多，而應(ying)該一(yi)點一(yi)點慢慢吃，所以(yi)完全放(fang)電后充電，比有余電時充電的(de)電量更小(xiao)一(yi)些(xie)，時間(jian)(jian)也更長一(yi)些(xie)。