A charging system includes: a power management integrated circuit, a bidirectional voltage conversion circuit, a controller and a battery level detection circuit. The bidirectional voltage conversion circuit is configured to work in a working mode including at least a boost mode and a buck mode. The controller has a first terminal. An input terminal of the battery level detection circuit is connected to a battery, an output terminal of the battery level detection circuit is connected to the first input terminal of the controller, and the battery level detection circuit is configured to detect a voltage and a current of the battery and transmit the voltage and the current of the battery to the controller. The controller is configured to control the working mode of the bidirectional voltage conversion circuit and a working state of the power management integrated circuit according to the battery voltage and the current.

A charging method, including: obtaining the number of charge-discharge cycles of a battery and an application scenario during charging; determining a target charging mode among at least two charging modes according to the number of charge-discharge cycles and the application scenario, in which different charging modes have different charging rates, and the charging modes with different charging rates have different charging damages to the battery; and charging the battery in the target charging mode.

A method of calculating a relative state-of-charge (RSOC) of a battery according to the disclosure includes measuring at least one parameter of the battery, based on the at least one parameter, estimating a state-of-charge (SOC) of the battery, based on the SOC, SOC-open circuit voltage (SOC-OCV) data of the battery, and the at least one parameter, estimating a non-dischargeable capacity of the battery, based on the non-dischargeable capacity of the battery, the SOC, and intrinsic capacity of the battery, estimating an available SOC (AvSOC) of the battery, based on the SOC and the AvSOC of the battery, determining the RSOC of the battery, and based on a ratio of the RSOC to the AvSOC, updating the RSOC of the battery.

A method is for replacing a rechargeable battery that is considered as an unsatisfactory rechargeable battery that needs replacing in an assembled battery in which rechargeable batteries are stacked and restrained in a row and electrically connected in series or in parallel. The method includes removing of finding at least one of the rechargeable batteries to be an unsatisfactory rechargeable battery in the assembled battery and removing the unsatisfactory rechargeable battery, and installing a satisfactory rechargeable battery, which has little deterioration, on at least one end of the row of the rechargeable batteries, in a row direction, in the assembled battery from which the unsatisfactory rechargeable battery has been removed.

A method of estimating a charging time of a battery, includes: estimating an SOC of the battery by measuring at least one parameter of the battery; estimating an internal resistance of the battery based on the at least one parameter of the battery, the SOC of the battery, and SOC-OCV data; estimating a time length of a constant current (CC) charging section based on the SOC, the internal resistance, and the at least one parameter of the battery; and estimating a time length of a constant voltage (CV) charging section based on the SOC, the internal resistance, and the at least one parameter of the battery. The estimating of the time length of the CV charging section includes: estimating a charging current of the battery in a unit of an SOC step; and calculating the time length of the CV charging section in the unit of the SOC step.

The present application describes systems and methods for authenticating rechargeable batteries in a rechargeable battery cabinet. The rechargeable battery cabinet may be a part of a large, scalable, distributed network of rechargeable battery cabinets, in which rechargeable battery cabinets may be removed or added based on consumer demand for fresh batteries. The system and methods may track the rechargeable batteries and where they are located in the rechargeable battery cabinets by first assigning a dynamic identification number, such that a rechargeable battery compartment does not need a static identifier. The system and method may allow for real-time reading of the status of rechargeable battery cabinets and rechargeable batteries in the system. Each rechargeable battery may have a static identifier to uniquely identify the rechargeable battery. This system and method allows for efficient scaling and identification of rechargeable battery within the system.

Methods and systems are provided for use of a portable speaker system both as part of a vehicular audio system and as a stand-alone audio system. A speaker may be attached to an internal speaker receptacle of a vehicle and coupling to an audio amplifier of the vehicle. Audio performances received by the speaker from the audio amplifier may then be played by the speaker. The speaker may also be decoupling from the audio amplifier of the vehicle and detached from the internal speaker receptacle of the vehicle. Audio performances received by the speaker from a wireless interface coupled to the speaker may then be played by the speaker.

An electric toothbrush, in combination with a universal base for receiving and wirelessly charging the toothbrush, the base to be coupled with the electric toothbrush for wireless communication therebetween. The base comprises a magnetic element for forming a magnetic connection with the electric toothbrush when the latter is received by the base for charging. The base includes a charging component for inductively charging the electric toothbrush, a Bluetooth component for communicating usage data received from the toothbrush during a brushing session, an analyzing component for instantaneous processing of the usage data received from the toothbrush, a timer-clock component for displaying either a count-up or a countdown of the brushing session during the brushing session and time of day before and after the brushing session, and a multi-functional light component for instantaneously communicating, during the brushing session, at least one element of the usage data.

In an example embodiment, a system includes an inverter configured to operate in at least one of a charging mode or a drive mode, a cascaded direct current (DC)-DC converter, the DC-DC converter including a first portion of the inverter and at least one controller configured to selectively couple the first portion of the inverter to a first portion of the cascaded DC-DC converter during the charging mode, and selectively couple the inverter to a second portion of the cascaded DC-DC converter during the drive mode.

A battery management device manages a battery including a plurality of battery cells in which a change in OCV relative to a change in SOC is smaller in a first SOC range than in a second SOC range. The battery management device is configured to: accumulate a current flowing in each battery cell to calculate the SOC of the battery cell; when the calculated SOC has stayed in the first SOC range for a predetermined period or more, control the cell balancing circuits in such a way that the SOC of a target battery cell selected from the battery cell s falls within the second SOC range; and calculate the SOC of the target battery cell based on the relationship between the SOC and the OCV in the second SOC range and correct the SOC of each battery cell by the amount of correction obtained based on the calculated SOC.