聚合物鋰電池在電池市場上占主導地位，但是你知道嗎？聚合物鋰電池電解質是有液體和固態之分的，下面就來了解一下吧。

（一）聚(ju)合(he)物鋰電(dian)池的液態電(dian)解質

電(dian)(dian)(dian)(dian)(dian)(dian)解質的(de)(de)選用(yong)對鋰離(li)子電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)性能影響非(fei)常大，它必須是(shi)(shi)化學穩(wen)定性能好尤(you)其是(shi)(shi)在(zai)較(jiao)高的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)位(wei)下和(he)較(jiao)高溫度(du)環境中不易(yi)發生分解，具有較(jiao)高的(de)(de)離(li)子導電(dian)(dian)(dian)(dian)(dian)(dian)率(lv)，而(er)且(qie)對陰陽極(ji)材料必須是(shi)(shi)惰(duo)性的(de)(de)，不能浸腐它們。由(you)于鋰離(li)子電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)充(chong)放電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)位(wei)較(jiao)高而(er)且(qie)陽極(ji)材料嵌(qian)有化學活性較(jiao)大的(de)(de)鋰，所以電(dian)(dian)(dian)(dian)(dian)(dian)解質必須采用(yong)有機(ji)化合物而(er)不能含有水。但有機(ji)離(li)子導電(dian)(dian)(dian)(dian)(dian)(dian)率(lv)都不好，所以要在(zai)有機(ji)溶劑(ji)中加入可溶解的(de)(de)導電(dian)(dian)(dian)(dian)(dian)(dian)鹽以提高離(li)子導電(dian)(dian)(dian)(dian)(dian)(dian)率(lv)。目(mu)前鋰離(li)子電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)主(zhu)要是(shi)(shi)用(yong)液態(tai)電(dian)(dian)(dian)(dian)(dian)(dian)解質，其溶劑(ji)為無水有機(ji)物，多數(shu)采用(yong)混合溶劑(ji)。

常見的(de)(de)有機(ji)液(ye)(ye)體電(dian)解(jie)(jie)質一(yi)般(ban)是1molL鋰(li)鹽/混合碳酸脂溶(rong)劑構成(cheng)的(de)(de)體系(xi)。作為(wei)傳(chuan)遞電(dian)荷(he)與傳(chuan)質過程的(de)(de)介質，鋰(li)離子(zi)電(dian)池適(shi)用的(de)(de)電(dian)解(jie)(jie)液(ye)(ye)通常應(ying)滿足(zu)以(yi)下(xia)幾方(fang)面的(de)(de)要求(qiu)：

A.在(zai)較寬的溫度(du)范圍(wei)(wei)內具有較高的電導率，最(zui)好(hao)達到（1~2）×10-3S/cm以上，鋰(li)離子遷(qian)移數盡(jin)可能高；B.液(ye)態溫度(du)范圍(wei)(wei)（液(ye)程）寬，至少在(zai)-20~80℃范圍(wei)(wei)內為液(ye)體；C.化學穩定性好(hao)，與電極活(huo)性物質（如正、負(fu)極材(cai)抖(dou)）、集流體、隔膜等基本上不發生反應

D.與電極(ji)材料的(de)相(xiang)容性(xing)好，能形成(cheng)穩定、有效的(de)鈍化膜；

E.電(dian)(dian)化學穩定性(xing)好，分解電(dian)(dian)壓高(gao)，以減少電(dian)(dian)池的(de)自放電(dian)(dian)和工(gong)作時電(dian)(dian)池內壓的(de)升高(gao)；F.閃點(dian)、燃點(dian)高(gao)，安全性(xing)好；G.環境友(you)好性(xing)，分解產物(wu)對環境影響較小。

上述要求是實現(xian)鋰(li)(li)離子電(dian)池低內阻、長壽命和高安全性(xing)的重要保證。鋰(li)(li)鹽、有機溶劑的選擇和電(dian)解(jie)質(zhi)溶液的優(you)化(hua)決定著電(dian)池的循(xun)環效率、工作(zuo)電(dian)壓、操作(zuo)溫度(du)和儲存(cun)期限等是開發(fa)鋰(li)(li)離子電(dian)池的關鍵技(ji)術(shu)之(zhi)一。從某種意(yi)義(yi)上說，鋰(li)(li)離子電(dian)池液體(ti)電(dian)解(jie)質(zhi)對電(dian)池性(xing)能具(ju)有決定性(xing)的作(zuo)用。

經(jing)過(guo)幾十年的(de)(de)(de)研究(jiu)和(he)實踐，鋰(li)離(li)子(zi)電池使(shi)用(yong)的(de)(de)(de)電解(jie)(jie)(jie)液己基本成(cheng)型，商品(pin)(pin)化(hua)(hua)的(de)(de)(de)電解(jie)(jie)(jie)液一般選(xuan)擇LiPF6作為鋰(li)鹽，溶劑(ji)多為碳酸(suan)乙烯脂（EC）與碳酸(suan)二甲(jia)脂（DMC）或(huo)者碳酸(suan)二乙酯（DEC）構成(cheng)的(de)(de)(de)混合溶劑(ji)。此(ci)外，還有(you)少量基于特殊目(mu)的(de)(de)(de)使(shi)用(yong)的(de)(de)(de)電解(jie)(jie)(jie)液體(ti)系。這些(xie)電解(jie)(jie)(jie)液體(ti)系，支撐著鋰(li)離(li)子(zi)電池的(de)(de)(de)商品(pin)(pin)化(hua)(hua)以及今后的(de)(de)(de)研究(jiu)和(he)發展。

（二(er)）聚合物鋰(li)電池的(de)固態電解質

用(yong)(yong)(yong)金(jin)屬(shu)鋰(li)(li)直接(jie)用(yong)(yong)(yong)作(zuo)陽(yang)極材料(liao)具有很(hen)高(gao)的(de)(de)(de)(de)可(ke)(ke)(ke)(ke)逆容量(liang)，其(qi)理論(lun)容量(liang)高(gao)達3862mAh.g1，是(shi)石墨材料(liao)的(de)(de)(de)(de)十幾倍(bei)，價格也較(jiao)低(di)，被(bei)看作(zuo)新一代鋰(li)(li)離(li)子(zi)(zi)(zi)(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)最有吸引力的(de)(de)(de)(de)陽(yang)極材料(liao)，但會(hui)產生(sheng)(sheng)枝(zhi)晶(jing)(jing)鋰(li)(li)。采用(yong)(yong)(yong)固(gu)(gu)體(ti)(ti)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)作(zuo)為(wei)陽(yang)極材料(liao)成(cheng)為(wei)可(ke)(ke)(ke)(ke)能(neng)。此(ci)(ci)外使用(yong)(yong)(yong)固(gu)(gu)體(ti)(ti)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)可(ke)(ke)(ke)(ke)避免液(ye)態(tai)(tai)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)液(ye)漏夜的(de)(de)(de)(de)缺點(dian)(dian)，還可(ke)(ke)(ke)(ke)把電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)作(zuo)成(cheng)更(geng)薄（厚度(du)(du)僅為(wei)0.1mm），能(neng)量(liang)密度(du)(du)更(geng)高(gao)，體(ti)(ti)積更(geng)小的(de)(de)(de)(de)高(gao)能(neng)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)。破壞(huai)(huai)性(xing)(xing)(xing)實驗表明固(gu)(gu)態(tai)(tai)鋰(li)(li)離(li)子(zi)(zi)(zi)(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)使用(yong)(yong)(yong)安(an)全性(xing)(xing)(xing)能(neng)很(hen)高(gao)，經釘穿，加熱，短路(lu)和(he)過(guo)充等(deng)破壞(huai)(huai)性(xing)(xing)(xing)實驗，液(ye)態(tai)(tai)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)鋰(li)(li)離(li)子(zi)(zi)(zi)(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)會(hui)發生(sheng)(sheng)漏夜、爆(bao)炸等(deng)安(an)全性(xing)(xing)(xing)問題，而固(gu)(gu)態(tai)(tai)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)除內溫略有升(sheng)高(gao)外并無(wu)任何其(qi)它安(an)全性(xing)(xing)(xing)問題出現(xian)。固(gu)(gu)態(tai)(tai)聚(ju)合(he)(he)物(wu)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)具有良好的(de)(de)(de)(de)柔(rou)韌性(xing)(xing)(xing)、成(cheng)膜性(xing)(xing)(xing)、穩定性(xing)(xing)(xing)、成(cheng)本低(di)等(deng)特(te)點(dian)(dian)，即可(ke)(ke)(ke)(ke)作(zuo)為(wei)陰陽(yang)電(dian)(dian)(dian)(dian)(dian)(dian)極間隔膜用(yong)(yong)(yong)又可(ke)(ke)(ke)(ke)作(zuo)為(wei)傳遞離(li)子(zi)(zi)(zi)(zi)(zi)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)用(yong)(yong)(yong)。固(gu)(gu)體(ti)(ti)聚(ju)合(he)(he)物(wu)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)一般(ban)可(ke)(ke)(ke)(ke)分為(wei)干性(xing)(xing)(xing)固(gu)(gu)體(ti)(ti)聚(ju)合(he)(he)物(wu)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)和(he)凝膠聚(ju)合(he)(he)物(wu)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)。固(gu)(gu)體(ti)(ti)聚(ju)合(he)(he)物(wu)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)主要(yao)還是(shi)基(ji)于聚(ju)氧化(hua)乙(yi)烯，其(qi)缺點(dian)(dian)是(shi)離(li)子(zi)(zi)(zi)(zi)(zi)導(dao)(dao)(dao)電(dian)(dian)(dian)(dian)(dian)(dian)率(lv)較(jiao)低(di)，在(zai)固(gu)(gu)體(ti)(ti)聚(ju)合(he)(he)物(wu)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)中(zhong)離(li)子(zi)(zi)(zi)(zi)(zi)傳導(dao)(dao)(dao)主要(yao)是(shi)發生(sheng)(sheng)在(zai)無(wu)定性(xing)(xing)(xing)區，借助聚(ju)合(he)(he)物(wu)鏈(lian)的(de)(de)(de)(de)移(yi)動(dong)進行遷移(yi)。聚(ju)氧化(hua)乙(yi)烯容易結(jie)晶(jing)(jing)是(shi)由于其(qi)分子(zi)(zi)(zi)(zi)(zi)鏈(lian)的(de)(de)(de)(de)高(gao)規整性(xing)(xing)(xing)，而晶(jing)(jing)形(xing)化(hua)會(hui)降低(di)離(li)子(zi)(zi)(zi)(zi)(zi)導(dao)(dao)(dao)電(dian)(dian)(dian)(dian)(dian)(dian)率(lv)。因此(ci)(ci)要(yao)想提(ti)(ti)高(gao)離(li)子(zi)(zi)(zi)(zi)(zi)導(dao)(dao)(dao)電(dian)(dian)(dian)(dian)(dian)(dian)率(lv)一方面可(ke)(ke)(ke)(ke)通過(guo)降低(di)聚(ju)合(he)(he)物(wu)的(de)(de)(de)(de)結(jie)晶(jing)(jing)度(du)(du)，提(ti)(ti)高(gao)鏈(lian)的(de)(de)(de)(de)可(ke)(ke)(ke)(ke)移(yi)動(dong)性(xing)(xing)(xing)，另(ling)一方面可(ke)(ke)(ke)(ke)通過(guo)提(ti)(ti)高(gao)導(dao)(dao)(dao)電(dian)(dian)(dian)(dian)(dian)(dian)鹽(yan)(yan)(yan)在(zai)聚(ju)合(he)(he)物(wu)中(zhong)的(de)(de)(de)(de)溶(rong)解(jie)(jie)度(du)(du)。利用(yong)(yong)(yong)接(jie)枝(zhi)、嵌段、交聯、共聚(ju)等(deng)手段來破壞(huai)(huai)高(gao)聚(ju)物(wu)的(de)(de)(de)(de)結(jie)晶(jing)(jing)性(xing)(xing)(xing)能(neng)，可(ke)(ke)(ke)(ke)明顯的(de)(de)(de)(de)提(ti)(ti)高(gao)其(qi)離(li)子(zi)(zi)(zi)(zi)(zi)導(dao)(dao)(dao)電(dian)(dian)(dian)(dian)(dian)(dian)率(lv)。此(ci)(ci)外加入無(wu)機復合(he)(he)鹽(yan)(yan)(yan)也能(neng)提(ti)(ti)高(gao)離(li)子(zi)(zi)(zi)(zi)(zi)導(dao)(dao)(dao)電(dian)(dian)(dian)(dian)(dian)(dian)率(lv)。在(zai)固(gu)(gu)體(ti)(ti)聚(ju)合(he)(he)物(wu)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)中(zhong)加入介電(dian)(dian)(dian)(dian)(dian)(dian)常數(shu)低(di)相對分子(zi)(zi)(zi)(zi)(zi)質(zhi)(zhi)(zhi)量(liang)的(de)(de)(de)(de)液(ye)態(tai)(tai)有機溶(rong)劑則(ze)可(ke)(ke)(ke)(ke)大大提(ti)(ti)高(gao)導(dao)(dao)(dao)電(dian)(dian)(dian)(dian)(dian)(dian)鹽(yan)(yan)(yan)的(de)(de)(de)(de)溶(rong)解(jie)(jie)度(du)(du)，所構成(cheng)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)即為(wei)凝膠聚(ju)合(he)(he)物(wu)電(dian)(dian)(dian)(dian)(dian)(dian)解(jie)(jie)質(zhi)(zhi)(zhi)，它在(zai)室溫下具有很(hen)高(gao)的(de)(de)(de)(de)離(li)子(zi)(zi)(zi)(zi)(zi)導(dao)(dao)(dao)電(dian)(dian)(dian)(dian)(dian)(dian)率(lv)，但在(zai)使用(yong)(yong)(yong)過(guo)程中(zhong)會(hui)發生(sheng)(sheng)析液(ye)而失敗。凝膠聚(ju)合(he)(he)物(wu)鋰(li)(li)離(li)子(zi)(zi)(zi)(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)已經商品化(hua)。