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Formation of size-dependent and conductive phase on lithium iron phosphate during carbon coating.

ABSTRACT: Carbon coating is a commonly employed technique for improving the conductivity of active materials in lithium ion batteries. The carbon coating process involves pyrolysis of organic substance on lithium iron phosphate particles at elevated temperature to create a highly reducing atmosphere. This may trigger the formation of secondary phases in the active materials. Here, we observe a conductive phase during the carbon coating process of lithium iron phosphate and the phase content is size, temperature, and annealing atmosphere dependent. The formation of this phase is related to the reducing capability of the carbon coating process. This finding can guide us to control the phase composition of carbon-coated lithium iron phosphate and to tune its quality during the manufacturing process.

SUBMITTER: Liu Y

PROVIDER: S-EPMC5834541 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Formation of size-dependent and conductive phase on lithium iron phosphate during carbon coating.

Liu Yulong Y Liu Jian J Wang Jiajun J Banis Mohammad Norouzi MN Xiao Biwei B Lushington Andrew A Xiao Wei W Li Ruying R Sham Tsun-Kong TK Liang Guoxian G Sun Xueliang X

Nature communications 20180302 1

Carbon coating is a commonly employed technique for improving the conductivity of active materials in lithium ion batteries. The carbon coating process involves pyrolysis of organic substance on lithium iron phosphate particles at elevated temperature to create a highly reducing atmosphere. This may trigger the formation of secondary phases in the active materials. Here, we observe a conductive phase during the carbon coating process of lithium iron phosphate and the phase content is size, tempe ...[more]

PMID: 29500399

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