The model aims to optimize the equalization current and ensure that the battery current is within safe range, and ultimately achieve the goal of reducing excessive battery heating and realizing safe, fast charging and discharging of the battery pack.
Why do lithium-ion batteries need a voltage-equalization control strategy?
In pursuit of low-carbon life, renewable energy is widely used, accelerating the development of lithium-ion batteries. Battery equalization is a crucial technology for lithium-ion batteries, and a simple and reliable voltage-equalization control strategy is widely used because the battery terminal voltage is very easy to obtain.
What is the efficient equalizing method for lithium-ion batteries?
An Efficient Equalizing Method for Lithium-Ion Batteries Based on Coupled Inductor Balancing. Electronics 2019, 8, 136. [Google Scholar] [Green Version] Chen, F.; Yuan, J.; Zheng, C.; Wang, C.; Li, Z.; Zhou, X. A State-of-Charge Based Active EV Battery Balancing Method.
Does equalization improve the inconsistency of a battery pack?
In the traditional fixed threshold method, when the equalization turn-on threshold is larger, the equilibrium speed of the battery pack will be improved to a certain extent, but the advantages of the equalization strategy designed in this article in improving the inconsistency of the battery pack will be more obvious.
The goal of equalization is to increase the battery pack's consistency as well as the battery pack's real capacity. The higher the equalization efficiency, the shorter the battery equalization time. The balancing goal can be formulated as: where represents the SOC of the ith battery, the battery pack has 2 n batteries in total, .
How to quantify the equalization effect of series-connected lithium-ion battery groups?
To better quantify the equalization effect, the battery difference and energy utilization rate are defined for evaluation. In order to address the inconsistency problem of series-connected lithium-ion battery groups in practice, a two-level balanced topology based on bidirectional Sepic-Zeta circuit is designed in this article.
Reference realized the safe charging of aged lithium batteries by using the MPC method. Compared with the traditional SOC control method, the battery pack SOC equalization is faster, the energy consumption is lower, and the over-equalization phenomenon can be avoided.