Inhomogeneous degradation of graphite anodes in automotive lithium ion batteries under low-temperature pulse cycling conditions

authored by

Daniel Burow, Kseniya Sergeeva, Simon Calles, Klaus Schorb, Alexander Börger, Christina Roth, Paul Heitjans

Abstract

The aging of graphite anodes in prismatic lithium ion cells during a low temperature pulse charging regime was studied by electrical tests and post-mortem analysis. The capacity decrease and impedance increase mainly occurs in the beginning of cycling and lithium plating was identified as the major aging mechanism. The degradation and the local states of charge show an inhomogeneous distribution over the anode, which is confirmed from spatially resolved XRD studies and SEM combined with EDX performed on electrode cross sections. Comparing a charged cell with a discharged cell reveals that ca. 1/3 of the lithium is plated reversibly at the given SOH of 60%. It is proposed that high charge rates at low temperatures induce inhomogeneities of temperature and anode utilization resulting in inhomogeneous aging effects that accumulate over lifetime.

Organisation(s)

Institute of Physical Chemistry and Electrochemistry

External Organisation(s)

Volkswagen AG
Freie Universität Berlin (FU Berlin)

Type

Article

Journal

Journal of power sources

Volume

307

Pages

806-814

No. of pages

9

ISSN

0378-7753

Publication date

01.03.2016

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Renewable Energy, Sustainability and the Environment, Energy Engineering and Power Technology, Physical and Theoretical Chemistry, Electrical and Electronic Engineering

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1016/j.jpowsour.2016.01.033 (Access: Closed)