Hyperbranched Triphenylamine Polymer for UltraFast Battery Cathode

Keiichi Yamamoto; Daichi Suemasa; Kana Masuda; Kazunari Aita; Takeshi Endo

doi:10.1021/acsami.7b17943

Hyperbranched Triphenylamine Polymer for UltraFast Battery Cathode

ACS Appl Mater Interfaces. 2018 Feb 21;10(7):6346-6353. doi: 10.1021/acsami.7b17943. Epub 2018 Feb 9.

Authors

Keiichi Yamamoto¹, Daichi Suemasa¹, Kana Masuda¹, Kazunari Aita¹, Takeshi Endo²

Affiliations

¹ Advanced Materials Research Laboratories, JSR Corporation , 100, Kawajiri-cho, Yokkaichi, Mie 510-8552, Japan.
² Molecular Engineering Institute, Kindai University , 11-6, Kayanomori, Iizuka, Fukuoka 820-8555, Japan.

PMID: 29381051
DOI: 10.1021/acsami.7b17943

Abstract

A novel hyperbranched poly(triphenylamine) (PHTPA) was synthesized, and the electrochemical properties of this material were studied. PHTPA was synthesized by a facile method in a one-step reaction from affordable monomers. Despite all aromatic structures, PHTPA showed good solubility in several organic solvents. The battery performance test of PHTPA showed a high discharge voltage, an ultrafast charge-discharge performance of 100-300 C, and a long cycle life of more than 5000 cycles. Moreover, the addition of the PHTPA to LiFePO₄ (LFP) improved the charge-transfer resistance and Warburg coefficient, which is related to the diffusion of lithium ions in LFP, and consequently improved the charge-discharge performance of LFP itself at a high C rate (20-100 C). This behavior is understood to be the result of the organic-inorganic charge transfer. The superior cycle performance of the PHTPA-LFP hybrid cathode was also found. PHTPA will serve as an additive for a high-performance LIB.

Keywords: hyperbranched polymer; long cycle life; organic−LFP hybrid cathode; organic−inorganic charge transfer; triphenylamine polymer; ultrafast battery.