TECHNICAL FIELD

The present disclosure relates to the field of battery technology, and more particularly to a method, an apparatus and a system for controlling charging of a battery module.

BACKGROUND

With the wide utilization of new energy sources, a battery module may be used as a power source in various fields. In order to increase the life of the battery module, the battery module can generally charge and discharge in cycles and thus can be recycled.

Moreover, due to a user's high requirement to usage experience of the battery module, the user may no longer use a charging speed as a single evaluation index to evaluate the battery module. The life for cycle charging and discharging of the battery module may become an evaluation index for evaluating the battery module as well. However, most of existing battery modules have a relatively short life for cycle charging and discharging. Taking a lithium battery as an example, a process for cycle charging and discharging the battery module is a process of repeatedly rapid insertion and extraction of lithium ions. In this process, the anode graphite in the battery module is rapidly expanding due to the rapid insertion of the lithium ions, and the pressure generated by the expansion causes a squeezing effect inside the battery module. When the pressure in the battery module increases to a certain value, the electrolyte and lithium ions in the battery module will be redistributed to make the lithium ions highly concentrated at a certain part of the battery module. This may result in side reactions in the battery module, deteriorate the recycle of the battery module, and consequently reduce the life for cycle charging of the battery module.

SUMMARY

A method, an apparatus and a system for controlling charging of a battery module are provided in embodiments of the present disclosure.

According to an aspect, a method for controlling charging of the battery module is provided in an embodiment of the present disclosure. The method may include: acquiring an internal pressure value of the battery module; determining a target pressure threshold range to which the acquired internal pressure value of the battery module belongs, based on a plurality of predefined pressure threshold ranges; obtaining a target charge cutoff voltage corresponding to the target pressure threshold range, based on a correspondence relationship between a plurality of predefined charge cutoff voltage and the plurality of predefined pressure threshold ranges; and controlling the battery module to be charged based on the obtained target charge cutoff voltage.

According to another aspect, an apparatus for controlling charging of the battery module is provided in an embodiment of the present disclosure. The apparatus may include: a pressure acquisition unit configured to acquire an internal pressure value of the battery module; a pressure threshold range determination unit configured to determine a target pressure threshold range to which the acquired internal pressure value of the battery module belongs, based on a plurality of predefined pressure threshold ranges; a lookup unit configured to obtain a target charge cutoff voltage corresponding to the target pressure threshold range, based on a correspondence relationship between a plurality of predefined charge cutoff voltage and the plurality of predefined pressure threshold ranges; and a charge control unit configured to control the battery module to be charged based on the obtained target charge cutoff voltage.

According to a further aspect, a system for controlling charging of the battery module is provided in an embodiment of the present disclosure. The system may include the above apparatus for controlling charging of the battery module; and at least one pressure sensor provided on each battery cell in the battery module and/or between two adjacent battery cells in the battery module, and configured to sense an internal pressure of the battery module.

