Hybrid/Asymmetric EESs based on the mechanism of “faradaic” or “extrinsic/intrinsic pseudocapacitive” can certainly overcome the EDLCs’ energy density limitation [3,4,5]. In light of this, K&W/TUAT group developed an original material processing technology called “ultracentrifugation (UC)” that allows to prepare (mass produce) a variety of ultrafast (Li-insertion) nanomaterials capable of 3-7 fold enhancement in energy density. It’ s been demonstrated that UC process typically under 75,000g (with subsequent heat or hydrothermal treatment) gives spinel Li₄Ti₅O₁₂ nanocrystal as nanosheet/nanobook that are grown on the surface of carbon matrices like MWCNT, SGCNT [1,2,4]. The “nanohybrid capacitor(NHC)” configured as uc-LTO/LiBF₄[PC] /AC tripled the energy density of conventional EDLCs [1,3,4]. Nippon Chemi-con Corp. is now eagerly developing commercial NHC device in order to place them in the market. Other uc-derived nanomaterials will be introduced together with their effective utilization in the 2^nd gen. “NanoHybrid Capacitor” (JST NexTEP project, 2013-2018) and 3^rd gen. “SuperRedox Capacitor” (JST A-step project, 2016-2021). As for LTO alternative anodes, b-axis (ultrashort) controlled 5-nm uc-TiO₂(B) [6] and electrochemically activated uc-Li₃VO₄ [7], both showed ultrafast (300C) charge-storage performances. As cathode, nano-structured 2-cores/1-shell of [uc-LiFePO₄(LFP)/amorphous/defective LFP/graphitic carbon] shows ultrafast and symmetric discharge and charge performance (300-480C) [8]. Finally, the author will present a perspective of the future supercapacitors’ market in the world.

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[4] K. Naoi et al, Accounts Chemical Research, 46,1075(2013).

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[6] E. Iwama and K. Naoi et al, ACS Nano, 10(5), 5398, (2016).

[7] K. Naoi et al, Advanced Materials, 28, 6751 (2016).

[8] K. Naoi et al, Energy & Environmental Science, 9, 2143 (2016).