Abstract: Embodiments of the present disclosure provide an active equalizer circuit, a battery management system, a power supply system and an electrical equipment. The active equalizer circuit comprises a plurality of switching transistors, a driving transformer, a multi-port converter, a buck converter, and a microcontroller. Each of the switching transistors is coupled to a battery cell in the series battery pack on a one-to-one basis. The multi-port converter comprises an equalizing transformer and a bridge converter, each secondary winding of the bridge converter is coupled to a corresponding plurality of battery cells. The buck converter has an input terminal coupled to an output terminal of the series battery pack and an output terminal coupled to an input terminal of the bridge converter.

Abstract: The present invention provides a thermal insulation composition and a preparation method and application. The thermal insulation composition is composed of aerogel material and organic resin; the composite mass ratio of the aerogel material to the organic resin is 5 wt %:95 wt % to 50 wt %:50 wt %; the porosity of the aerogel material is greater than 95%, the pore diameter of the aerogel material is less than or equal to 100 nm, the particle size of each particle of aerogel material is 5 nm to 20 nm, and the organic resin is filled in the pores of the aerogel material. The thermal insulation module component prepared from the thermal insulation composition has mechanical strength and thermal conductivity at room temperature, and if the battery goes into thermal runaway, the material becomes a heat-insulating material, blocking the heat transfer between battery cells, greatly improving the safety performance of the battery.