Tohoku University · 공학
Kazuaki Kisu 교수의 연구실은 고에너지 밀도 및 저비용을 목표로 하는 마그네슘 및 calcium 이온 배터리의 핵심 소재 개발에 중점을 두고 있습니다. 특히 고도로 안정된 전해질, 고이온 전도성 고체 전해질, 나노구조 전극 재료의 설계 및 합성을 통해 실용적인 전기화학적 에너지 저장 장치의 실현 가능성을 탐색하고 있습니다. 복합수소화물, 칼슘 복합체, 나노캡슐화된 산화스티늄 등 다양한 재료를 활용한 혁신적 소재 기반의 배터리 기술 개발이 핵심 연구 방향입니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Magnesium borohydride ammonia borane, Mg(BH4)2(NH3BH3)2, was electrochemically investigated. Impedance measurements of the mechanochemically synthesized Mg(BH4)2(NH3BH3)2 exhibited an ionic conductivity of 1.3 × 10–5 S cm–1 at 30 °C. Electrochemical cells fabricated with Mg(BH4)2(NH3BH3)2 as the solid electrolyte demonstrated reversible Mg migration through the material, indicating its potential for use as a Mg ionic conductor in all-solid-state Mg-ion batteries.
High-energy-density and low-cost calcium (Ca) batteries have been proposed as 'beyond-Li-ion' electrochemical energy storage devices. However, they have seen limited progress due to challenges associated with developing electrolytes showing reductive/oxidative stabilities and high ionic conductivities. This paper describes a calcium monocarborane cluster salt in a mixed solvent as a Ca-battery electrolyte with high anodic stability (up to 4 V vs. Ca<sup>2+</sup>/Ca), high ionic conductivity (4 m
Single-nanocrystalline SnO<sub>2</sub> particles encapsulated within hollow-structured carbon structures were synthesized. Encapsulated SnO<sub>2</sub> is readily transformed into a blended amorphous structure composed of Li<sub>x</sub>SnO<sub>1.45</sub> (<italic>x</italic> = 0–7.3) after repeated lithiation–delithiation processes.
Spherical LiMn<sub>0.792</sub>Fe<sub>0.198</sub>Mg<sub>0.010</sub>PO<sub>4</sub>nanocrystals, which are highly dispersed and encapsulated within the interstices of supergrowth (single-walled) carbon nanotubes (SGCNTs), were successfully synthesized by<italic>in situ</italic>material processing technology called “ultra-centrifuging (UC) treatment”.
As potential alternatives to Li-ion batteries, rechargeable Ca metal batteries offer advantageous features such as high energy density, cost-effectiveness, and natural elemental abundance. However, challenges, such as Ca metal passivation by electrolytes and a lack of cathode materials with efficient Ca<sup>2+</sup> storage capabilities, impede the development of practical Ca metal batteries. To overcome these limitations, the applicability of a CuS cathode in Ca metal batteries and its electroc
Water molecules are exchanged in the crystal structure, which imparts a high divalent conductivity to hydrated complex hydrides. MB 12 H 12 ·12H 2 O (M = Zn or Mg) exhibits exceptional conductivities higher than those of less-hydrated complex hydrides.
Rechargeable Ca batteries offer the advantages of high energy density, low cost, and earth-abundant constituents, presenting a viable alternative to lithium-ion batteries. However, using polymer electrolytes in practical Ca batteries is not often reported, despite its potential to prevent leakage and preserve battery flexibility. Herein, a Ca(BH<sub>4</sub>)<sub>2</sub>-based gel-polymer electrolyte (GPE) is prepared from Ca(BH<sub>4</sub>)<sub>2</sub> and poly(tetrahydrofuran) (pTHF) and tested
Multivalent-ion and all-solid-state batteries have emerged as potential solutions to address resource concerns and safety issues.
The use of Ca metal in battery technology is a promising approach owing to its high energy density and sustainability. However, the increased battery resistance during extended cycling significantly narrows its application range. This study aimed to improve the long-term stability of Ca deposition by employing a dual-salt strategy based on calcium monocarborane, Ca(CB<sub>11</sub>H<sub>12</sub>)<sub>2</sub>, which demonstrated favorable Ca deposition characteristics as a single-salt electrolyte.
Efficient Ca plating/stripping and the development of low-volatility electrolytes remain key challenges for the broad-scale application of Ca metal batteries. In this study, we demonstrate that CaBr<sub>2</sub> addition modifies the electrolyte environment, enabling highly reversible Ca plating/stripping in electrolytes based on low-volatility diglyme as a solvent previously considered nonfunctional.
1. Introduction Olivine phosphates have long been investigated as cathode material in Li-ion batteries. In particular, lithium iron phosphate (LiFePO 4 ) has attracted the attention of many researchers because of its high theoretical capacity of 170 mAh g -1 , low cost and high electrochemical/thermal stabilities of the phosphate (PO 4 3- ) anion [1] . However, the large volume difference during two-phase reaction between Li-rich Li 1-a FePO 4 (LFP) and Li-poor Li b FePO 4 (FP) phases leads to l
