A battery pack which has cell units in which top-side and bottom-side battery cells are connected in series, and is capable of switching the connection state of the cell units, wherein a control unit monitors voltage imbalances between the plurality of cell units, and also monitors whether or not a cell unit contact failure has occurred. In order to stop a charging/discharging when a contact failure occurs, a signal (abnormality stoppage signal or charging stoppage signal) for stopping discharge is produced and outputted to the electrical device body-side.

The disclosure provides a charger, a charging device, an energy supply device and a control method of the charger. The charger comprises a housing, a charging position, a charging port and a first heat dissipation unit. The charger comprises a base and a supporting part. The supporting part is arranged on the base. The charging position is arranged on the base and distributed around the supporting part. The charging port is arranged on the charging position and matched with a battery pack. The first heat dissipation unit is arranged on the supporting part for heat dissipation of the battery pack. With the charger of the disclosure, multiple battery packs can be charged at the same time.

A battery charging method includes during charging of a battery, upon determining that a state of charge (SOC) of the battery reaches an SOC range, adjusting, within a range from a minimum boundary value of the SOC range to a set SOC, a charge rate of the battery from a first charge rate down to a second charge rate; and adjusting, within a range from the set SOC to a maximum boundary value of the first SOC range, the charge rate of the battery from the second charge rate up to the first charge rate or a third charge rate.

An electrochemical device includes a negative electrode plate, a positive electrode plate and a separator provided between the negative electrode plate and the positive electrode plate. There are m negative tabs electrically connected to the negative electrode plate, wherein m is a positive integer greater than or equal to 1. There are n positive tabs electrically connected to the positive electrode plate, wherein n is a positive integer greater than 1, and n>m. The electrochemical device is charged with a multi-stage constant current charging method.

An electrical device including a surface which may be exposed to heat derived from operation of the electrical device such that the temperature of the surface increases during operation. The surface includes a temperature sensor including first and second electrodes separated by a layer of control material. The material properties and/or configuration of the control material are selected such that the electrical conductivity of the control material increases with increasing temperature so that electrical current is able to pass between the first and second electrodes once the temperature of any part of the control material has reached or exceeded a predetermined temperature. The temperature sensor extends over substantially the whole of the surface. A system including the electrical device and a method of controlling the electrical device is also disclosed.

In a method for operating an electric vehicle and an electric vehicle, including an electric traction drive device for driving vehicle, a control device for controlling the driving, a first energy storage device, for supplying the control device using a first DC voltage, a second energy storage device, for supplying the traction drive device using a second DC voltage, and an energy supply unit for providing an output DC voltage, the first energy storage device is connected to the second energy storage device via a converter device, the first energy storage device is connected to the energy supply unit, the converter device converts the first DC voltage into the second DC voltage, and a power flow from the second energy storage device to the first energy storage device is prevented.

A lithium battery system is provided. The lithium battery system comprises a battery pack, a battery management module, and a cooling control module. The battery pack comprises a first battery module and a second battery module having different battery characteristics. The battery management module is electrically connected to the battery pack, and configured to control an operating condition of the battery pack according to the battery characteristics of the first battery module and the second battery module. The cooling control module is electrically connected to the battery management module and the battery pack, and configured to cool the battery pack according to an instruction of the battery management module. The application combines a variety of lithium batteries with different performances to obtain a lithium battery system with excellent comprehensive performance.

The disclosure relates to the technical field of electric vehicles, and in particular, to a control method and apparatus for a traction battery, a vehicle, a medium, and a device, aiming at solving the problem of how to conveniently and efficiently heat a traction battery, especially a large-capacity traction battery. To this end, the control method for a traction battery according to an embodiment of the disclosure comprises analyzing whether each traction battery needs to be heated on the basis of temperature information of the traction battery, and controlling a bidirectional DC converter and the traction battery which needs to be heated to form a charging and discharging circuit to cyclically charge and discharge the traction battery, so as to achieve the goal of heating the traction battery. By means of the foregoing steps, the characteristic of high internal resistance of a lithium-ion traction battery at a low temperature can be used to make the traction battery generate heat by means of a cyclic charging and discharging process, to achieve the heating of the traction battery, that is, the performance of the traction battery can be improved, the time for charging the traction battery is reduced, and the safety of the traction battery is further improved.

Disclosed is a power storage unit which can safely operate over a wide temperature range. The power storage unit includes: a power storage device; a heater for heating the power storage device; a temperature sensor for sensing the temperature of the power storage device; and a control circuit configured to inhibit charge of the power storage device when its temperature is lower than a first temperature or higher than a second temperature. The first temperature is exemplified by a temperature which allows the formation of a dendrite over a negative electrode of the power storage device, whereas the second temperature is exemplified by a temperature which causes decomposition of a passivating film formed over a surface of a negative electrode active material.

Provided is a semiconductor device capable of stably estimating an internal temperature of a battery. A semiconductor device coupled to a battery calculates entropy heat of the battery at a predetermined time by using a charging current of the battery and an internal temperature of the battery at a time before a predetermined time, calculates a heat generation amount of the battery from the charging current of the battery, calculates a heat radiation amount of the battery based on a temperature difference between the internal temperature at the time before the predetermined time and a surface temperature of the battery, and estimates an internal temperature of the battery at the predetermined time by using the entropy heat, the heat generation amount and the heat radiation amount.