Degradation diagnostics for lithium ion cells

JOURNAL OF POWER SOURCES

卷:341

Article

Birkl, Christoph R.¹  Roberts, Matthew R.²  McTurk, Euan^2,3  Bruce, Peter G.²  Howey, David A.¹ 

[1] Univ Oxford, Dept Engn Sci, Oxford OX1 3PJ, England

[2] Univ Oxford, Dept Mat, Oxford OX1 3PH, England

[3] Univ Warwick, Warwick Mfg Grp, Warwick CV4 7AL, England

关键词: Lithium ion;    Degradation;    State of health;    Diagnostic;    Open circuit voltage;    Battery management system;   

DOI  :  10.1016/j.jpowsour.2016.12.011

来源: Elsevier

【 摘 要 】

Degradation in lithium ion (Li-ion) battery cells is the result of a complex interplay of a host of different physical and chemical mechanisms. The measurable, physical effects of these degradation mechanisms on the cell can be summarised in terms of three degradation modes, namely loss of lithium inventory, loss of active positive electrode material and loss of active negative electrode material. The different degradation modes are assumed to have unique and measurable effects on the open circuit voltage (OCV) of Li-ion cells and electrodes. The presumptive nature and extent of these effects has so far been based on logical arguments rather than experimental proof. This work presents, for the first time, experimental evidence supporting the widely reported degradation modes by means of tests conducted on coin cells, engineered to include different, known amounts of lithium inventory and active electrode material. Moreover, the general theory behind the effects of degradation modes on the OCV of cells and electrodes is refined and a diagnostic algorithm is devised, which allows the identification and quantification of the nature and extent of each degradation mode in Li-ion cells at any point in their service lives, by fitting the cells' OCV. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

【 授权许可】

Free