A novel rechargeable lithium air battery based on oxygen/peroxide redox couple

• Project/Area Number: 16H06055
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Device related chemistry
• Research Institution: Kobe University
• Principal Investigator: Matsui Masaki 神戸大学, 工学研究科, 准教授 (70639210)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥25,220,000 (Direct Cost: ¥19,400,000、Indirect Cost: ¥5,820,000); Fiscal Year 2018: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000); Fiscal Year 2017: ¥11,570,000 (Direct Cost: ¥8,900,000、Indirect Cost: ¥2,670,000); Fiscal Year 2016: ¥8,840,000 (Direct Cost: ¥6,800,000、Indirect Cost: ¥2,040,000)
• Keywords: 酸素還元 / 蓄電池 / 過酸化水素 / 触媒フリー / 空気電池 / 二電子反応 / 過酸化物 / 空気極 / 可逆性 / 二次電池 / 電気化学 / 水溶液 / 空気極反応メカニズム / 二電子還元反応 / 酸素還元反応 / その場分光分析

Outline of Final Research Achievements

In the present study, we conducted mechanistic analyses of aqueous Li-air battery using oxygen-peroxide redox couple. The reaction product Li2O2 was obtained using 18O2 labeled gas. The hydrolysis process of the formed Li2O2 proved that the peroxide is originally formed by the 18O2 labeled gas. The rotating ring-disk electrode study proved two electron-transfer process of the aqueous lithium-air system. In addition, the binder materials (such as Nafion) content is crucial for the improvement of the reversibility, because the electrolyte solution confined in the composite electrode initiates an effective precipitation of the Li2O2 to maintain the reversible reaction.

Academic Significance and Societal Importance of the Research Achievements

本研究は、既存のリチウムイオン電池に対して、飛躍的なエネルギー密度の向上が期待されているリチウム空気二次電池の充放電特性を向上するための新たな系として、酸素・過酸化水素のredox対の積極的な利用を提案するものである。本研究により、従来は理論エネルギー密度は高くても、それを活かしきれていなかったリチウム空気二次電池のエネルギー効率が大きく向上できる可能性が示唆された。また、可逆性を高める電極構造を提案することで、空気電池実用化への道筋を示すものである。

Research Products

• [Presentation] Electrochemical study of catalyst-free gas diffusion electrodes for lithium-oxygen batteries (2017)
  • Author(s): Yoshiki Hayakawa, Manato Uchida, Masaki Matsui, Hideyuki Horino and Nobuyuki Imanishi
  • Organizer: International Battery Association 2017
  • Place of Presentation: 奈良春日野国際フォーラム
  • Year and Date: 2017-03-06
  • Int'l Joint Research
• [Presentation] Manato Uchida, Yoshiki Hayakawa, Masaki Matsui and Nobuyuki Imanishi (2017)
  • Author(s): Characteristic Improvement of Catalyst-Free Novel Aqueous Lithium-Oxygen Battery
  • Organizer: International Battery Association 2017
  • Place of Presentation: 奈良春日野国際フォーラム
  • Year and Date: 2017-03-06
  • Int'l Joint Research
• [Presentation] Electrochemical study of catalyst-free gas diffusion electrode for lithium-oxygen batteries (2017)
  • Author(s): Yoshiki Hayakawa, Manato Uchida, Masaki Matsui, Hideyuki Horino and Nobuyuki Imanishi
  • Organizer: IBA 2017
  • Int'l Joint Research
• [Presentation] 触媒フリー水系リチウム空気二次電池の電極構造と可逆性 (2017)
  • Author(s): 早川佳樹、打田眞人、松井雅樹、堀野秀幸、今西誠之
  • Organizer: 第58回電池討論会
• [Presentation] 触媒フリー水系リチウム空気二次電池の反応メカニズム解析 (2016)
  • Author(s): 早川佳樹、打田眞人、松井雅樹、今西誠之
  • Organizer: 第57回電池討論会
  • Place of Presentation: 幕張メッセ
• [Presentation] 触媒フリー水系リチウム空気二次電池の特性向上 (2016)
  • Author(s): 打田眞人、早川佳樹、松井雅樹、今西誠之
  • Organizer: 第57回電池討論会
  • Place of Presentation: 幕張メッセ