A Simplified Model for the Battery Ageing Potential Under Highly Rippled Load for Battery Management and Active Degradation Control

TL;DR

This paper introduces a simplified electrochemical model to predict battery aging under rippled loads, enabling better management and active control of degradation in real-world applications.

Contribution

It develops a regression model capturing ripple effects on aging, facilitating parameter calibration and active aging control in battery management systems.

Findings

Model accurately predicts aging due to ripple currents.

Enables quantitative monitoring of ripple-induced aging.

Supports active control of battery degradation.

Abstract

Whereas in typical standardized tests batteries are almost exclusively loaded with constant current or relatively slowly changing cycles, real applications involve rapid load ripple, which do not contribute to the net energy. The trend to reduced filter capacitors and even dynamically reconfigurable batteries further increases the ripple. The influence of rippled load on lithium batteries is therefore receiving increased attention. According to recent studies, accelerated ageing strongly depends on the frequency of the ripple. We use electrochemical models to derive a highly simplified regression model that catches the asymptotic behavior and allows parameter identification and calibration to specific cells. The model allows quantitative monitoring of the additional ageing due to ripple current in battery management systems. Furthermore it enables active control of the ageing potential by influencing the frequency content in modern battery systems, such as reconfigurable batteries.