Detection of Internal Short Circuit in Li-ion Battery by Estimating its Resistance

Abstract

We propose an algorithm for estimating an internal short circuit (ISC) resistance in a Li-ion battery. With a simple equivalent model of the Li-ion battery and recursive least square (RLS) algorithm, open circuit voltage (OCV) and State of Charge (SOC) are estimated. By using the estimated OCV and SOC, the ISC resistance can be calculated and used as ISC fault index. To verify this algorithm, the simulation data from MATLAB/Simulink model and experiment data are used. The result shows that the proposed algorithm contributes to detect the ISC fault in Li-ion battery by using the new ISC fault index.

Detection of Internal Short Circuit in Lithium Ion Battery Using Model-Based Switching Model Method

“…A normal Li-ion battery can be represented by an equivalent circuit model (Figure 2a) [15,17,19] that consists of OCV , internal resistance , load current and terminal voltage . The Li-ion …”

“…A normal Li-ion battery can be represented by an equivalent circuit model (Figure 2a) [15,17,19] that consists of OCV V oc , internal resistance R, load current I and terminal voltage V t . The Li-ion battery with ISCr can be represented by a similar equivalent circuit model (Figure 2b) [15,17,20] where I 1 f is the current that flows within the battery, and I 2 f is the current that flows through the R ISC f .…”

“…The Li-ion battery with ISCr can be represented by a similar equivalent circuit model (Figure 2b) [15,17,20] where I 1 f is the current that flows within the battery, and I 2 f is the current that flows through the R ISC f .…”

“…For these reasons, studies to detect the ISCr have been presented [14][15][16][17]. The ISCr can be detected by determining certain thresholds such as reduction of terminal voltage and increase of batteries temperature [14], but to obtain the thresholds, this method requires prior ISCr tests with batteries.…”

“…An early version [17] of the algorithm proposed in this paper estimated by using selfdischarge from the ISCr to detect it, but the accuracy of estimates was low; to solve this problem, this paper presents a model-based switching model method (SMM). As a fault index, is estimated accurately by using SMM to detect the ISCr.…”