近日,據(ju)報(bao)道日本大型(xing)電(dian)池企業Maxell開發出了圓柱形(xing)全(quan)固態電(dian)池,其(qi)容(rong)(rong)量達到200毫安時,是(shi)傳統的(de)(de)陶瓷封裝(zhuang)型(xing)(方形(xing))容(rong)(rong)量的(de)(de)25倍。新電(dian)池具有耐熱性強、壽命長的(de)(de)特點,而且抗沖擊性好,被認(ren)為可以當(dang)作主電(dian)源使(shi)用(yong)。據(ju)說,Maxell的(de)(de)全(quan)固態電(dian)池已被尼(ni)康的(de)(de)工業機(ji)械用(yong)傳感器采用(yong)等,訂單正在(zai)增(zeng)加(jia)。
1月3日美國固(gu)態(tai)電(dian)池QuantumScape公司表(biao)示,其固(gu)態(tai)電(dian)池通過了德國大眾(zhong)公司的50萬(wan)公里(li)耐(nai)久性測(ce)試。測(ce)試數據還顯示,配(pei)備 QuantumScape電(dian)池的電(dian)動汽車,WLTP 續(xu)航(hang)里(li)程為 500-600公里(li),在電(dian)池的全(quan)生(sheng)命(ming)周期內,可以行(xing)駛(shi)超過50萬(wan)公里(li),不會有任何(he)續(xu)航(hang)能(neng)力衰退。
盡(jin)管從歐洲(zhou)到日本(ben),都(dou)在加速(su)開發全固態電(dian)池(chi), 但鑒于技術(shu)難(nan)題和高昂成本(ben),未來一(yi)兩年內半固態電(dian)池(chi)或將(jiang)成為電(dian)池(chi)技術(shu)創新和應用的重要發展方向。
首先,我(wo)們來了解下(xia)半固(gu)態(tai)電池和全(quan)固(gu)態(tai)電池的區別(bie)是什么。
半固態電(dian)(dian)池(chi):相比液態電(dian)(dian)池(chi),半固態電(dian)(dian)池(chi)減少電(dian)(dian)解(jie)液的(de)用(yong)(yong)量,增加聚(ju)合(he)物(wu)+氧化物(wu)復合(he)電(dian)(dian)解(jie)質,其中聚(ju)合(he)物(wu)以框架(jia)網絡形式填充,氧化物(wu)主(zhu)要以隔(ge)膜涂(tu)覆+正(zheng)負極(ji)包覆形式添加,此外負極(ji)從(cong)(cong)石墨體系升(sheng)級(ji)到預鋰(li)化的(de)硅基負極(ji)/鋰(li)金屬負極(ji),正(zheng)極(ji)從(cong)(cong)高鎳(nie)升(sheng)級(ji)到了高鎳(nie)高電(dian)(dian)壓/富鋰(li)錳基等,隔(ge)膜仍(reng)保留(liu)并涂(tu)覆固態電(dian)(dian)解(jie)質涂(tu)層,鋰(li)鹽從(cong)(cong)LiPF6升(sheng)級(ji)為(wei)LiTFSI,封(feng)裝(zhuang)方式主(zhu)要采用(yong)(yong)卷繞/疊(die)片+方形/軟包的(de)方式,能(neng)量密度可達350Wh/kg以上。
全固態電(dian)池(chi):相(xiang)比(bi)液(ye)(ye)態電(dian)池(chi),全固態電(dian)池(chi)取消原有電(dian)解液(ye)(ye),選用(yong)聚(ju)合(he)物(wu)(wu)(wu)/氧化(hua)(hua)(hua)(hua)物(wu)(wu)(wu)/硫化(hua)(hua)(hua)(hua)物(wu)(wu)(wu)體系作(zuo)(zuo)為固態電(dian)解質,以(yi)薄膜(mo)的形式分割正負(fu)極(ji),從而替代隔膜(mo)的作(zuo)(zuo)用(yong),其中聚(ju)合(he)物(wu)(wu)(wu)性能上限較低,氧化(hua)(hua)(hua)(hua)物(wu)(wu)(wu)目前進展較快,硫化(hua)(hua)(hua)(hua)物(wu)(wu)(wu)未來潛力(li)最大,負(fu)極(ji)從石墨體系升(sheng)級(ji)到預鋰化(hua)(hua)(hua)(hua)的硅基(ji)負(fu)極(ji)/鋰金屬負(fu)極(ji),正極(ji)從高鎳升(sheng)級(ji)到了超(chao)高鎳/鎳錳酸(suan)鋰/富鋰錳基(ji)等,封裝方式采(cai)用(yong)疊片+軟包的方式,能量密度可(ke)達500Wh/kg。
固(gu)態電池界面(mian)(mian)為固(gu)-固(gu)接觸,離(li)子電導率(lv)低、界面(mian)(mian)穩(wen)定性差,存在循(xun)環、快充等問題,制約其(qi)商業化進程(cheng)。
材料端離子(zi)電(dian)(dian)導(dao)率低:固態(tai)電(dian)(dian)池(chi)中(zhong),電(dian)(dian)極與電(dian)(dian)解質(zhi)之間(jian)的界面接(jie)觸(chu)由固-液接(jie)觸(chu)變(bian)為(wei)固-固接(jie)觸(chu),由于(yu)固相無潤(run)濕性(xing),因此接(jie)觸(chu)面積小,形成更高(gao)的界面電(dian)(dian)阻(zu)。同時固體電(dian)(dian)解質(zhi)中(zhong)有大量的晶界存在(zai)(zai),且(qie)晶界電(dian)(dian)阻(zu)往往高(gao)于(yu)材料本(ben)體電(dian)(dian)阻(zu),不利于(yu)鋰離子(zi)在(zai)(zai)正負(fu)極之間(jian)傳(chuan)輸,從(cong)而影響快充性(xing)能和循環壽命。
循(xun)環(huan)壽命差(cha):固(gu)-固(gu)接(jie)觸為剛性接(jie)觸,對電(dian)(dian)極(ji)材(cai)料體積(ji)變(bian)化(hua)更(geng)為敏感,循(xun)環(huan)過程中容易造(zao)(zao)成電(dian)(dian)極(ji)顆粒(li)之間以及(ji)電(dian)(dian)極(ji)顆粒(li)與(yu)電(dian)(dian)解(jie)質接(jie)觸變(bian)差(cha),造(zao)(zao)成應力堆積(ji),導致(zhi)電(dian)(dian)化(hua)學(xue)性能(neng)衰(shuai)(shuai)減,甚至(zhi)導致(zhi)裂(lie)縫(feng)的出現,造(zao)(zao)成容量迅(xun)速衰(shuai)(shuai)減,導致(zhi)循(xun)環(huan)壽命差(cha)的問題。
全固(gu)(gu)(gu)態電(dian)(dian)池界面(mian)接觸問題較為嚴重(zhong),工藝尚不(bu)成熟,生產成本(ben)高昂(ang)。固(gu)(gu)(gu)態電(dian)(dian)解質缺(que)乏流(liu)動(dong)性,導致固(gu)(gu)(gu)-固(gu)(gu)(gu)接觸面(mian)積小(xiao),阻抗增大等問題出現,整體電(dian)(dian)導率較低,制約固(gu)(gu)(gu)態電(dian)(dian)池產業化應(ying)用。
固態電(dian)(dian)解質(zhi)是實現高安(an)全性(xing)(xing)(xing)、能(neng)量密度(du)、循環壽命(ming)性(xing)(xing)(xing)能(neng)的關鍵。根據(ju)電(dian)(dian)解質(zhi)的種(zhong)類,可分為(wei)(wei)氧(yang)化(hua)(hua)(hua)物(wu)(wu)(wu)、硫化(hua)(hua)(hua)物(wu)(wu)(wu)、聚合(he)物(wu)(wu)(wu)三種(zhong)路線。聚合(he)物(wu)(wu)(wu)體(ti)系率(lv)(lv)(lv)先在歐洲商業化(hua)(hua)(hua),優點(dian)為(wei)(wei)易于(yu)加工、生產工藝(yi)兼容、界面相(xiang)容性(xing)(xing)(xing)好(hao)(hao)、機械性(xing)(xing)(xing)能(neng)好(hao)(hao),缺(que)點(dian)為(wei)(wei)常溫(wen)離子(zi)電(dian)(dian)導(dao)率(lv)(lv)(lv)低(di)、電(dian)(dian)化(hua)(hua)(hua)學窗口略窄、熱穩(wen)定(ding)(ding)性(xing)(xing)(xing)和(he)能(neng)量密度(du)提升有(you)限,因此制約了其大規模應用;氧(yang)化(hua)(hua)(hua)物(wu)(wu)(wu)綜(zong)合(he)性(xing)(xing)(xing)能(neng)最(zui)(zui)好(hao)(hao),優點(dian)為(wei)(wei)電(dian)(dian)化(hua)(hua)(hua)學窗口寬、熱穩(wen)定(ding)(ding)性(xing)(xing)(xing)好(hao)(hao)、機械強(qiang)度(du)高,缺(que)點(dian)為(wei)(wei)難以加工、界面相(xiang)容性(xing)(xing)(xing)差(cha)(cha)、電(dian)(dian)導(dao)率(lv)(lv)(lv)一般。整體(ti)看,氧(yang)化(hua)(hua)(hua)物(wu)(wu)(wu)體(ti)系制備難度(du)適中,較多人(ren)和(he)國內企業選取此路線,預計采(cai)用與(yu)(yu)聚合(he)物(wu)(wu)(wu)復合(he)的方式,在半固態電(dian)(dian)池中率(lv)(lv)(lv)先規模化(hua)(hua)(hua)裝車;硫化(hua)(hua)(hua)物(wu)(wu)(wu)發(fa)展潛(qian)力最(zui)(zui)大,優點(dian)為(wei)(wei)電(dian)(dian)導(dao)率(lv)(lv)(lv)高、兼具強(qiang)度(du)與(yu)(yu)加工性(xing)(xing)(xing)能(neng)、界面相(xiang)容性(xing)(xing)(xing)好(hao)(hao),缺(que)點(dian)為(wei)(wei)與(yu)(yu)正極材料兼容度(du)差(cha)(cha)、對鋰金屬(shu)穩(wen)定(ding)(ding)性(xing)(xing)(xing)差(cha)(cha)、對氧(yang)氣和(he)水分敏感(gan)、存在潛(qian)在污染問題、生產工藝(yi)要求高。硫化(hua)(hua)(hua)物(wu)(wu)(wu)目前處于(yu)研發(fa)階(jie)段(duan),但后續發(fa)展潛(qian)力最(zui)(zui)大,工藝(yi)突破(po)后,可能(neng)成(cheng)為(wei)(wei)未來主流路線。
根據(ju)目前(qian)來(lai)看(kan),固態電池市場上(shang)早(zao)已有之,但不是(shi)應用于(yu)汽車動力(li)。如果(guo)應用于汽車(che)動力市場(chang)的車(che)規級固(gu)態電池得到(dao)量產(chan),那(nei)無疑(yi)將開創一個新時代(dai)。
海外(wai)市場似乎(hu)挺樂觀,并(bing)發力直接(jie)開(kai)發車規級(ji)全固態(tai)電(dian)(dian)池(chi);國內市場則更(geng)穩健(jian)與實(shi)在些,目前(qian)半(ban)固態(tai)電(dian)(dian)池(chi)已量產并(bing)應用,下一步就(jiu)是全固態(tai)電(dian)(dian)池(chi)的(de)推(tui)出(chu)了。
近(jin)兩年,不少人(ren)認為,2030年才(cai)能到達固態(tai)(tai)電(dian)池時代。然而,綜(zong)合目(mu)前趨勢來看,固態(tai)(tai)電(dian)池時代或將更(geng)快到來,各大電(dian)池廠商需要(yao)早(zao)作準備!