State of health estimation of LiFePO4 / graphite cells

Yancheng Zhang, Chao Yang Wang

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Scopus citations

Abstract

A new method is proposed to estimate state of health (SoH) of LiFePO 4/graphite cells using partial charge capacity (PCC) between 3.5 and 3.6 V. A degradation index (DI), defined as the ratio of the current PCC to the initial PCC (for a fresh cell) at the same conditions, is found to linearly correlate with the SoH. The PCC is measured at constant current charging, which can readily be implemented and is much easier than using discharge diagnosis dependent on road and driving conditions. This method only needs to record charging time between 3.5 and 3.6 V during constant current charging, but does not require full discharge before the charging and any additional sensors or complex computations of model-based approaches. Consequently, it is an efficient and simple method to estimate the SoH of LiFePO4/graphite cells by using the PCC-based degradation index.

Original languageEnglish (US)
Title of host publicationCorrosion, Passivity, and Energy
Subtitle of host publicationA Symposium in Honor of Digby D. Macdonald
Pages275-281
Number of pages7
Edition31
DOIs
Publication statusPublished - Dec 1 2012
EventCorrosion, Passivity, and Energy: A Symposium in Honor of Digby D. Macdonald - PRiME 2012 - Honolulu, HI, United States
Duration: Oct 7 2012Oct 12 2012

Publication series

NameECS Transactions
Number31
Volume50
ISSN (Print)1938-5862
ISSN (Electronic)1938-6737

Other

OtherCorrosion, Passivity, and Energy: A Symposium in Honor of Digby D. Macdonald - PRiME 2012
CountryUnited States
CityHonolulu, HI
Period10/7/1210/12/12

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All Science Journal Classification (ASJC) codes

  • Engineering(all)

Cite this

Zhang, Y., & Wang, C. Y. (2012). State of health estimation of LiFePO4 / graphite cells. In Corrosion, Passivity, and Energy: A Symposium in Honor of Digby D. Macdonald (31 ed., pp. 275-281). (ECS Transactions; Vol. 50, No. 31). https://doi.org/10.1149/05031.0275ecst