The invention discloses a
power battery fault diagnosis method and
system. The method comprises the following steps: establishing a
voltage matrix of a
battery cell, extracting a sub-matrix interval of the
voltage matrix, establishing a median matrix according to the median of the
battery cell voltage in the sub-matrix interval, establishing a voltage
deviation matrix according to the sub-matrix interval and the median matrix, calculating a voltage deviation increment according to a voltage deviation value in the voltage
deviation matrix, establishing a voltage deviation increment matrix, accumulating the number of times that the voltage deviation value in the voltage
deviation matrix exceeds a set interval, establishing a voltage deviation accumulation number matrix, establishing a jointmatrix, performing two-dimensional clustering on the established joint matrix by adopting a
DBSCAN density clustering method, and judging whether the
battery cell has a fault or not according to a clustering result. According to the
power battery fault diagnosis method and
system provided by the invention, the fault judgment efficiency of the battery
cell can be improved, and the judgment accuracycan be improved.