我們都知道，鋰電池出廠的時候都會有相應的充放電電流要求，建議在規定的要求下使用電池，如果不按照要求，鋰電池放電倍率高于原有規定放電倍率有什么危害呢？

一般(ban)來(lai)說鋰(li)電(dian)池(chi)隨著充(chong)放電(dian)次數的(de)(de)增加，容量會越(yue)來(lai)越(yue)少，直接表現(xian)是鋰(li)電(dian)池(chi)的(de)(de)性能越(yue)來(lai)越(yue)差。那么都有哪些因素(su)影響到(dao)鋰(li)電(dian)池(chi)的(de)(de)性能呢？

    影響鋰電(dian)池(chi)容量(liang)的(de)因素有(you)很(hen)多，如(ru)使用溫度(du)、充放(fang)電(dian)電(dian)流、充放(fang)電(dian)截止電(dian)壓等(deng)因素都會影響鋰離子電(dian)池(chi)的(de)衰降(jiang)速度(du)。造(zao)成鋰電(dian)池(chi)容量(liang)衰降(jiang)的(de)機理可(ke)以分為三類：內(nei)阻和極化增加(jia)、正負(fu)極活性物質損失(shi)、Li損失(shi)。

    不(bu)(bu)同的(de)外部(bu)因素(su)對這三者的(de)影響也(ye)各不(bu)(bu)相同。例如LiFePO4材(cai)料的(de)鋰電(dian)池具(ju)有(you)非(fei)常好的(de)循環性(xing)能(neng)，但(dan)是(shi)不(bu)(bu)同的(de)使(shi)用條件(jian)對鋰電(dian)池循環壽(shou)命有(you)著重要(yao)的(de)影響。

    試驗(yan)證(zheng)明對鋰電(dian)(dian)池進行15C脈沖(chong)放(fang)電(dian)(dian)和15C連續放(fang)電(dian)(dian)，兩種放(fang)電(dian)(dian)制度對于鋰電(dian)(dian)池具(ju)有(you)完全不同的影響。15C脈沖(chong)放(fang)電(dian)(dian)的鋰電(dian)(dian)池容量衰降非常快(kuai)，充(chong)放(fang)電(dian)(dian)40次(ci)后(hou)無法再進行15C放(fang)電(dian)(dian)，但(dan)是仍(reng)然(ran)能夠(gou)進行1C放(fang)電(dian)(dian)。而15C連續放(fang)電(dian)(dian)電(dian)(dian)池容量衰降較慢，60次(ci)以后(hou)仍(reng)然(ran)能夠(gou)進行15C放(fang)電(dian)(dian)，但(dan)是1C倍率的衰降速率要快(kuai)于15C脈沖(chong)放(fang)電(dian)(dian)。

    鋰(li)電(dian)(dian)(dian)池的(de)充電(dian)(dian)(dian)策略對于鋰(li)電(dian)(dian)(dian)池壽命衰(shuai)(shuai)(shuai)降(jiang)影響的(de)研(yan)究(jiu)，能夠更好的(de)指導(dao)我們對鋰(li)離子(zi)電(dian)(dian)(dian)池的(de)設計。以下不(bu)同充電(dian)(dian)(dian)控(kong)制策略對鋰(li)離子(zi)電(dian)(dian)(dian)池壽命衰(shuai)(shuai)(shuai)降(jiang)的(de)影響，研(yan)究(jiu)了其(qi)作(zuo)用(yong)機理，提出鋰(li)離子(zi)電(dian)(dian)(dian)池的(de)壽命衰(shuai)(shuai)(shuai)降(jiang)模型(xing)。

    機理分析得出結論：15C脈沖放電(dian)(dian)的(de)(de)電(dian)(dian)池在負極的(de)(de)SEI膜(mo)中出現更(geng)多的(de)(de)LiF，而LiF對鋰離子擴散的(de)(de)阻(zu)礙更(geng)大，使得電(dian)(dian)池的(de)(de)Li+擴散阻(zu)抗和(he)電(dian)(dian)荷(he)交(jiao)換阻(zu)抗迅(xun)速(su)增加，從而使得電(dian)(dian)池在充放電(dian)(dian)過(guo)程(cheng)中極化電(dian)(dian)壓過(guo)大，從而導致LiFePO4大電(dian)(dian)流放電(dian)(dian)能力迅(xun)速(su)下降。

       從上述(shu)分(fen)析我們可(ke)以注意(yi)到，無論是(shi)充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)還是(shi)充(chong)電(dian)(dian)(dian)(dian)截止電(dian)(dian)(dian)(dian)壓(ya)都(dou)存在(zai)一個(ge)值，當充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)或者電(dian)(dian)(dian)(dian)壓(ya)超過這(zhe)(zhe)(zhe)個(ge)值時(shi)會導致(zhi)電(dian)(dian)(dian)(dian)池衰降(jiang)加速，對于上述(shu)電(dian)(dian)(dian)(dian)池這(zhe)(zhe)(zhe)個(ge)值是(shi)1C和4.2V，當充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)和截止電(dian)(dian)(dian)(dian)壓(ya)超過這(zhe)(zhe)(zhe)個(ge)值后會加速電(dian)(dian)(dian)(dian)池的(de)衰降(jiang)；當小于這(zhe)(zhe)(zhe)個(ge)值時(shi)，提高充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)和截止電(dian)(dian)(dian)(dian)壓(ya)并(bing)不會顯著的(de)增(zeng)加電(dian)(dian)(dian)(dian)池的(de)衰降(jiang)速度。

    對于(yu)充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)和截止電(dian)(dian)(dian)壓對電(dian)(dian)(dian)池(chi)衰降速度影響的(de)機理研究顯(xian)示，當充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)低于(yu)1C時主(zhu)要影響的(de)是正負極活性物質損失，而截止電(dian)(dian)(dian)壓低于(yu)4.2V時影響的(de)主(zhu)要是Li損失，當充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)和截止電(dian)(dian)(dian)壓高于(yu)這個值時，則會顯(xian)著的(de)加速正負極活性物質損失和Li損失。