System and method for equalizing cell

Abstract

The invention provides a system for equalizing a cell. The system comprises monitoring acquisition module, a control module and an energy management module, wherein the monitoring acquisition module is used for monitoring and collecting the voltage and temperature of unit cells and selectively starting a corresponding energy management unit in an energy management module according to a discharging control signal; the control module is used for setting a voltage threshold value according to the voltage of the unit cells, comparing the voltage with the voltage threshold value to select one or more unit cells to be discharged, and calculating cell polarization internal resistance and cell residual charge of the corresponding unit cells according to the voltage and the temperature of the unit cells to generate a discharging control signal; the energy management module comprises a plurality of energy management units which are connected with the unit cells in a one-to-one mode to start and control the corresponding unit cells to be discharged to discharge to charge a cell set. The system utilizes integrated and modularization control, energy equalization is not consumption but transferring, and the equalizing efficiency is high. The invention further provides a method for equalizing the cell.

Description

technical field [0001] The invention relates to the technical field of automobile power batteries, in particular to a battery equalization system and method thereof. Background technique [0002] Energy-saving and environment-friendly vehicles represented by hybrid electric vehicles, pure electric vehicles, and fuel cell vehicles are the main direction of future model development, and they all use batteries as part or all of their power. Batteries are often composed of battery cells connected in series and parallel, but due to the difference in the manufacturing of battery cells and the use environment, that is, the absolute unevenness of the temperature field distribution in the battery pack, as the battery is used, the energy of the battery becomes more and more inconsistent. At this time, the battery cell with the smallest energy affects the use of the entire battery pack / battery module. [0003] At present, an external MOSFET tube (Metal-Oxide-Semiconductor Field-Effect...

AI Technical Summary

Problems solved by technology

[0005] The existing battery balancing method is passive balancing, that is, the energy of the single battery with more energy can only be passively consumed to achieve the energy balancing of the entire battery pack.

Since the consumed energy is dissipated in the form of heat (resistors and MOSFET tubes), the existing technology has the disadvantages of large heat generation and low equilibrium efficiency

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