Connection Failure Detection for Lithium-ion Batteries Based on DBSCAN-Projection Method

Abstract

This paper presents a connection failure detection for a Lithium-ion battery pack when no external vibrations exist. First, the gradient correction method is employed to identify the overall ohmic resistance, which is the summation of the internal and external (contact) resistance. Second, the battery state of health (SOH) is estimated with incremental capacity analysis (ICA) - based method. Third, Density-Based Spatial Clustering of Applications with Noise (DBSCAN) method is applied to diagnose the connection failure by matching the calculated resistance with the estimated SOH. Finally, a linear projection is applied to reduce the method sensitivity to the testing conditions such as different state of charge (SOC). Experiments show that the proposed method can identify the location of the connection failure well in real time.