ET module/whole PACK charging and discharging series is a portable charging and discharging device developed for the charging and discharging maintenance of modular battery modules or whole pack battery packs. It realizes small volume and high power through the feed-net design, and is easy to carry. It is suitable for remote travel of service personnel, and quickly realizes the voltage matching of automobile battery modules/energy storage cartridges, as well as the daily maintenance of whole battery packs or modules. Battery module capacity calibration.