BATTERY MODULE, BATTERY PACK, ELECTRIC APPARATUS, AND METHOD AND DEVICE FOR MANUFACTURING BATTERY MODULE

The present application relates to a battery module, comprising a first type of battery cells and a second type of battery cells electrically connected at least in series, wherein the first and second type of battery cells are battery cells of different chemical systems, the first type of battery cells comprises N first battery cells, the second type of battery cells comprises M second battery cells, and N and M are positive integers; a positive electrode plate of the second battery cell contains two or more positive electrode active materials, and when a dynamic SOC of the second battery cell is in a range from 90% to 98%, a change rate ΔOCV/ΔSOC in an OCV relative to the SOC of the second battery cell satisfies 3≤ΔOCV/ΔSOC≤9, in mV/% SOC, where SOC represents a charge state and OCV represents an open circuit voltage.