Predictive control method for charging passive equalization of lithium battery

Abstract

The invention relates to a predictive control method for charging passive equalization of a lithium battery. The predictive control method is suitably used for an arbitrary battery pack comprising a plurality of lithium batteries. An acquisition equalization circuit board is connected to each single battery, and all acquisition equalization circuit boards are cascaded in series by a mode of serial daisy chain and are connected with a control plate; an equalization voltage range is preset, and an equalization function is not allowed to be executed when the difference between maximum voltage and minimum voltage of the single battery in the batter pack is larger than 500mV; meanwhile, the voltage difference is set within a range of 50-500mV, and the equalization function adopts a corresponding equalization current according to a corresponding linear proportion; and after the battery pack is started to charge, the voltage of each single battery in the battery pack is started to be detected and acquired in real time, the equalization function of the single battery is started when the voltage of a certain single is detected to be higher than an average voltage of the battery pack and a voltage range allowable for equalization is reached, and the equalization function is stopped when the voltage of the single battery is equal to the average voltage.

Description

technical field [0001] The invention belongs to the field of battery charging and discharging management, in particular to a predictive control method for passive equalization of lithium battery charging. Background technique [0002] As the production and manufacturing technology of lithium batteries becomes more and more mature and the manufacturing cost becomes lower and lower, the backup system of the data center begins to increase the use of lithium batteries to replace traditional lead-acid batteries. In the manufacturing process of lithium batteries, due to process problems or uneven materials, there are slight differences in the thickness of the battery polarity and the activation degree of the active material. The incomplete consistency of the internal structure and materials of the battery is just It will make it impossible for the batteries of the same model in the same batch to be completely consistent in terms of capacity, internal resistance, and voltage. Duri...

AI Technical Summary

Problems solved by technology

The direct performance is that the consistency of different single cells in a battery pack will gradually deteriorate during use, and the voltage of the single cells will vary greatly, which will eventually lead to a serious drop in battery capacity.

[0003] After the batteries are packed into groups, the battery life is much lower than that of single batteries. There are differences between individual batteries. When charging, the battery with the smallest capacity is easy to be overcharged. into a vicious circle

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