关于iPhone11的电池使用寿命问题，官方的说法是iPhone电池在(zai)经过500次充(chong)放(fang)电(dian)循环后，电(dian)量(liang)不(bu)会低(di)于80%。那么一次完整的(de)充(chong)放(fang)电(dian)周期怎么计算(suan)呢(ni)，是不(bu)是手(shou)机(ji)电(dian)量(liang)从100%到0%呢(ni)，iPhone11剩余多少电(dian)量(liang)开始充(chong)电(dian)好，下(xia)文我(wo)们一起来(lai)探(tan)个(ge)究竟。
iPhone电(dian)(dian)(dian)池(chi)采(cai)用(yong)的是锂(li)离(li)子技术，锂(li)离(li)子电(dian)(dian)(dian)池(chi)以(yi)充电(dian)(dian)(dian)周(zhou)(zhou)期方式(shi)工作(zuo)(zuo)，工作(zuo)(zuo)原理(li)为(wei)(wei)锂(li)离(li)子Li+通过电(dian)(dian)(dian)解质在(zai)电(dian)(dian)(dian)池(chi)正(zheng)极(ji)和负极(ji)之间移动，Li+从(cong)正(zheng)极(ji)游(you)离(li)到负极(ji)为(wei)(wei)充电(dian)(dian)(dian)过程(cheng)，再从(cong)负极(ji)游(you)离(li)到正(zheng)极(ji)为(wei)(wei)放(fang)电(dian)(dian)(dian)过程(cheng)。全部的Li+完成一次充放(fang)电(dian)(dian)(dian)过程(cheng)即(ji)为(wei)(wei)电(dian)(dian)(dian)池(chi)的一个循环(huan)周(zhou)(zhou)期，所以(yi)也(ye)就是说iPhone11电(dian)(dian)(dian)池(chi)电(dian)(dian)(dian)量(liang)从(cong)0%到100%再到0%可以(yi)作(zuo)(zuo)为(wei)(wei)一个循环(huan)周(zhou)(zhou)期。
然(ran)而日常(chang)生活中，我们并(bing)没有每次都(dou)(dou)是电(dian)(dian)量(liang)为0%时(shi)开始充(chong)电(dian)(dian)，也不是每次都(dou)(dou)是从电(dian)(dian)量(liang)为100%时(shi)开始使用，所以不能单从一(yi)次充(chong)电(dian)(dian)和放电(dian)(dian)行为来定义(yi)一(yi)个循环(huan)，而应该(gai)从电(dian)(dian)量(liang)使用达到(dao)100%来作为一(yi)个循环(huan)。我们参照苹果官方对充(chong)电(dian)(dian)循环(huan)说明：
“你可随时随需为 Apple 锂(li)离子(zi)电(dian)(dian)(dian)(dian)(dian)(dian)池充(chong)(chong)(chong)电(dian)(dian)(dian)(dian)(dian)(dian)。在充(chong)(chong)(chong)电(dian)(dian)(dian)(dian)(dian)(dian)之前，无需先 100% 放电(dian)(dian)(dian)(dian)(dian)(dian)。Apple 锂(li)离子(zi)电(dian)(dian)(dian)(dian)(dian)(dian)池以(yi)充(chong)(chong)(chong)电(dian)(dian)(dian)(dian)(dian)(dian)周期方式工作。如果使用 (放电(dian)(dian)(dian)(dian)(dian)(dian)) 的电(dian)(dian)(dian)(dian)(dian)(dian)量(liang)达到(dao)电(dian)(dian)(dian)(dian)(dian)(dian)池容量(liang)的 100%，你就完成了一(yi)个充(chong)(chong)(chong)电(dian)(dian)(dian)(dian)(dian)(dian)周期，但不(bu)一(yi)定通过一(yi)次充(chong)(chong)(chong)电(dian)(dian)(dian)(dian)(dian)(dian)来(lai)完成。”
意思是比(bi)如在iPhone11电(dian)量(liang)为(wei)20%时开(kai)始(shi)充(chong)电(dian)，充(chong)到(dao)80%后再(zai)放电(dian)到(dao)20%，那(nei)么这次用的(de)(de)(de)(de)电(dian)量(liang)为(wei)一(yi)个(ge)循(xun)(xun)(xun)环(huan)的(de)(de)(de)(de)60%；当我们再(zai)次充(chong)电(dian)到(dao)70%，再(zai)次放电(dian)到(dao)30%时，这次用的(de)(de)(de)(de)电(dian)量(liang)为(wei)一(yi)个(ge)循(xun)(xun)(xun)环(huan)的(de)(de)(de)(de)40%；此时两(liang)个(ge)过程累计达到(dao)一(yi)个(ge)循(xun)(xun)(xun)环(huan)的(de)(de)(de)(de)100%，就(jiu)算(suan)电(dian)池的(de)(de)(de)(de)一(yi)个(ge)循(xun)(xun)(xun)环(huan)周期(qi)。
也就是说日常使用无论一次、还是两次甚至多次充放电，只有累计放电量达到100%时，才算一个循环周期。
了解锂电池的循(xun)环(huan)周(zhou)期后不(bu)难发现(xian)，iPhone11的电池寿命(ming)并不(bu)是(shi)跟(gen)使(shi)用(yong)时间(jian)直接相关(guan)，而是(shi)跟(gen)使(shi)用(yong)次(ci)(ci)数和(he)(he)每次(ci)(ci)的使(shi)用(yong)电量有(you)关(guan)。一(yi)(yi)天循(xun)环(huan)两次(ci)(ci)比(bi)一(yi)(yi)天循(xun)环(huan)一(yi)(yi)次(ci)(ci)使(shi)用(yong)寿命(ming)短(duan)，同样一(yi)(yi)个(ge)月(yue)用(yong)掉电量2%和(he)(he)两个(ge)月(yue)用(yong)掉1%都属于正常情况。
下图为中度(du)使用一年的iPhone xs，已完成(cheng)充放电循环450次左右(you)，电量容量还有86%。
最后要(yao)补(bu)充(chong)的是锂离子电(dian)(dian)池(chi)(chi)并没有以往镍镉电(dian)(dian)池(chi)(chi)的记忆效应，所(suo)以日常(chang)无需等iPhone11电(dian)(dian)量用(yong)尽或充(chong)满(man)再(zai)使用(yong)，可随时(shi)为其(qi)充(chong)电(dian)(dian)，电(dian)(dian)量充(chong)足性能发挥更(geng)佳。
更多相关内容可查看极悦娱乐官网iPhone11充电专栏。
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