Battery data storage method and device and battery management system

The invention relates to the technical field of battery data storage, in particular to a battery data storage method and device and a battery management system, and the method comprises the steps: carrying out the data collection of a battery system according to a preset sampling period, and obtaining original battery data; searching updated data for the original battery data by adopting a difference storage method to obtain difference battery data; obtaining a current load parameter of a local operation environment, and selecting to obtain an optimal compression strategy by using a preset compression strategy selection algorithm according to the current load parameter; according to the optimal compression strategy, performing compression processing on the differential battery data by using a preset basic dictionary to obtain coded battery data; and respectively storing the coded battery data in a local storage area and transmitting the coded battery data to a cloud server so as to complete the storage of the