Abstract: This present disclosure discloses a transformer. The transformer comprises a lithium battery pack, a transformer coil and 2N switches. The lithium battery pack comprises N single batteries connected in series. The transformer coil comprises a magnetic core, N first windings and N second windings. The N first windings combined into one strand, the N second windings combined into one strand, are then wound on the magnetic core respectively. The N first windings and the N second windings have same number of coil turns, same homonymous ends and same common ends. Two ends of each single battery are connected with one first of the first windings and one of the second windings in parallel respectively. Each first winding is connected with one switch in series. Each second winding is connected with one switch in series. N is a natural number greater than or equal to 1.

Abstract: The present disclosure provides a battery management system with protection and equalization functions including a dedicated battery management IC, a plurality of sampling circuits and a plurality of execution circuits. A battery protection module and an equalization module are integrated in the dedicated battery management IC. The sampling circuits and the execution circuits are coupled between the dedicated battery management IC and a lithium battery pack, respectively. The sampling circuit collects parameters including voltage, charge-discharge current and battery temperature of the lithium battery pack and inputs them into the dedicated battery management IC for analysis and processing. The dedicated battery management IC outputs control signals to the execution circuits according to a result of the analysis and processing of the parameters, to control the execution circuits to perform battery protection function and voltage equalization function of the lithium battery pack.

Abstract: A single-interface charging-discharging switchable circuit comprising a power management unit U1, field effect transistors Q1˜Q2, capacitors C1˜C5, resistors R1˜R8, a diode D1 and an inductor L1. The product fills the gap in the market where there is no automatic charging-discharging switching circuit with the same interface, which enables the same interface (VCC/GND) to realize discharging and charging functions. The circuit of the disclosure is simple and has broad application prospects. The product of the disclosure uses a 5V-30V power supply to charge, and mobile phone adapters, portable power supply and other 5V power supply can be used as chargers. It is not limited by the 5V voltage of the traditional power supply, and the range of the input voltage of charging is wide.

Abstract: A single-interface charging-discharging switchable circuit comprising a power management unit U1, field effect transistors Q1˜Q2, capacitors C1˜C5, resistors R1˜R8, a diode D1 and an inductor L1. The product fills the gap in the market where there is no automatic charging-discharging switching circuit with the same interface, which enables the same interface (VCC/GND) to realize discharging and charging functions. The circuit of the disclosure is simple and has broad application prospects. The product of the disclosure uses a 5V-30V power supply to charge, and mobile phone adapters, portable power supply and other 5V power supply can be used as chargers. It is not limited by the 5V voltage of the traditional power supply, and the range of the input voltage of charging is wide.