The invention relates to the technical field of
power battery safety, in particular to a safety early warning method and device for a
power battery, and the method specifically comprises the following steps: S1, marking a sample, and obtaining the basic information and operation data of the carried battery; s2, screening
discharge condition data and cleaning the data; s3, setting a sliding window; s4, calculating an entropy value of
voltage ranking of each
monomer in each group; s5, calculating the entropy slope of the entropy of the
voltage ranking of each
monomer in each group along with the change of mileage, and preliminarily positioning the risk
battery cell; s6, feature parameters of all samples are extracted and calculated; s7, training the model by adopting a
random forest algorithm; and S8, collecting the
data set marked as the to-be-evaluated vehicle
data set, extracting the entropy slope of each
battery cell of the to-be-analyzed battery, and judging an abnormal
battery cell. According to the safety early warning method of the
power battery provided by the invention, the abnormal single battery
cell possibly having an internal
short circuit risk can be identified in time, and the accuracy and reliability of safety early warning are improved.