BATTERY DEVICE, DETECTION METHOD THEREOF, METHOD AND DEVICE FOR SCREENING BATTERY CELLS

The disclosure discloses a battery device, a detection method thereof, a method and device for screening battery cells. The characteristic values are determined according to parameters of two peaks in the frequency-domain impedance diagram. The characteristic values may reflect the magnitude of charge transfer impedance and diffusion impedance in each battery cell, then reflect the characteristics of the interface and characteristics of solid phase particles during charging and discharging, and further reflect the health and performance of battery cells. The battery set screened in this way still have good consistency after storage and shelving, and the consistency between battery cells will not deteriorate after storage for a period of time, so that the battery device may have better performance. In addition, the consistency between battery cells in the battery device may be dynamically monitored, which reflects the consistency of the battery cells during use, realize online monitoring of the battery cells, and provide guidance for the subsequent use of the battery device.