複合型的固態電解質結合高分子與無機填料(陶瓷材料、二氧化矽)之優點,特別是高分子主體PVDF-HFP與PPC具有良好的機械性質、穩定的電化學窗口等優勢,兩種材料可有效提升電池的電化學特性,並添加相較於商用電池極少量的離子液體,可降低固態電解質與電極的界面電阻,更接近全固態鋰電池的未來趨勢。 本研究之高分子由聚偏氟乙烯-六氟丙烯共聚物(Poly vinylidene fluoride-hexafluoropropylene,PVDF-HFP)作為主體,添加少量聚碳酸亞丙酯(Poly propylene carbonate,PPC)進行混摻,將兩者混合後塗佈並烘乾形成固態高分子電解質層作為對照組,實驗組則添加二氧化矽奈米材料(SiO2)作為被動填料,或是已添加已參雜金屬鉭(Ta)或金屬鋁(Al)之陶瓷材料(LLZTO、LLZAO)作為主動填料,探討無機填料加入高分子中形成複合型固態電解質,對於材料本身及電化學性質的影響。 實驗搭配NCM811為正極系統,鋰金屬為負極,於室溫下進行充放電分析。實驗結果發現SiO2作為被動填料可表現出較高分子優異的電化學特性。添加10wt% SiO2於PVDF-HFP/PPC中,可得低速比電容量(207.14 mAh/g @ 25 mA/g)、高速比電容量(122.79 mAh/g @ 300 mA/g)、離子導率(7.81 ×10-4 S/cm)、鋰離子遷移率(tLi+=0.43)。 另一種本身含有元素鋰之主動填料(LLZTO、LLZAO),其中又以添加10wt.%-LLZAO於PVDF-HFP/PPC有最佳電性表現:具備低速比電容量(228.87 mAh/g @ 25 mA/g)、高速比電容量(161.50 mAh/g @ 300 mA/g)、離子導率(8.84 ×10-4 S/cm)、鋰離子遷移率(tLi+=0.47)。 透過本研究得知,透過添加適量無機填料(SiO2、LLZTO、LLZAO)於固態高分子電解質,可使電性有明顯提升,皆有助於未來固態電解質之發展。 ;Lithium metal batteries (LMBs) have recently been regarded as a potential energy source. However, safety issues arising from the leakage of liquid organic solvents and the growth of lithium dendrites need to be addressed. Therefore, replacing liquid electrolytes with solid-state composite electrolytes (SCEs)1 may be a promising solution. The SCEs in this study are mainly composed of poly-vinylidene fluoride-hexafluoropropylene (PVDF-HFP) and poly-propylene carbonate (PPC) and inorganic fillers such as silicon dioxide (SiO2) particles, Ta-Li7La3Zr2O12 (LLZTO) or Al-Li7La3Zr2O12 (LLZAO). The SCEs combine the advantages of good mechanical properties and a wide electrochemical window provided by polymers. Additionally, the inorganic fillers are used to reduce the crystallinity and enhance the Li+ transportation by forming a space-charge region and the acid-base interaction. At last, add a trace amount of ionic liquid relative to commercial lithium batteries in order to reduce the interface resistance between the membrane and electrodes. A solid-state composite NCM811|SiO2-PVDF-HFP/PPC|Li battery exhibits an initial discharge capacity of 207.14 mAh/g @ 25 mA/g, 122.79 mAh/g @ 300 mA/g, ionic conductivity of 7.81×10-4 S/cm, and a lithium transference number of 0.43. Another solid-state composite NCM811|LLZAO-PVDF-HFP/PPC|Li battery exhibits an initial discharge capacity of 228.87 mAh/g @ 25 mA/g, 161.50 mAh/g @ 300 mA/g, ionic conductivity of 8.84×10-4 S/cm, and a lithium transference number of 0.47.