Abstract: The present inventive concept provides a state of charge value estimation method for a lithium battery, including determining an estimated state of charge value by using an ampere-hour integral method; and when estimating that the lithium battery enters a low-current charging mode, determining a reference cell voltage value corresponding to the estimated state of charge value according to a look-up table, and comparing the reference cell voltage value and a measured real-time cell voltage value to determine a calibrated state of charge value. The state of charge value estimation method for a lithium battery of the present inventive concept is simple in operation and high in accuracy.

Abstract: The present invention relates to an equalization circuit, a charging device, and an energy storage device connected between a battery pack and a charger. The battery pack comprises a plurality of cells connected in series. The equalization circuit comprises: a detection module used for detecting a voltage, temperature, and/or current of each cell; an auxiliary charging module used for providing a second charging current to the battery pack, wherein the second charging current is less than a first charging current provided by the charger to the battery pack; and a control module used for controlling the detection module and the auxiliary charging module.

Abstract: The present invention relates to an equalization circuit, a charging device, and an energy storage device connected between a battery pack and a charger. The battery pack comprises a plurality of cells connected in series. The equalization circuit comprises: a detection module used for detecting a voltage, temperature, and/or current of each cell; an auxiliary charging module used for providing a second charging current to the battery pack, wherein the second charging current is less than a first charging current provided by the charger to the battery pack; and a control module used for controlling the detection module and the auxiliary charging module.