Performance of Passive and Active Balancing Systems of Lithium Batteries in Onerous Mine Environment

Abstract

To use lithium-iron-phosphate battery packs in the supply systems of any electric mining equipment and/or machines, the required conditions of work safety must be met. This applies in particular to coal mines endangered by fire and/or explosion. To meet the spark-safety conditions, the cells (together with the battery management system—BMS) must be isolated from the influence of the environment, and therefore placed in special fire-tight housings. This significantly degrades the heat dissipation, thus affecting the operating conditions of the cell-packs. Therefore, their usage without the so-called BMS is not recommended, as shown in the authors’ preliminary research. In practice, various BMS are used, most often with the so-called passive balancing. However, their application in mines is uncertain, due to the effect of heating under operation. When it comes to active BMS, they usually possess a quite complex structure and hence, are relatively expensive. Therefore, the authors conducted research for two specially developed active and one commercial passive BMS cooperating with selected lithium-iron-phosphate (LiFePO4) batteries when used in a suspended mining vehicle type PCA-1. The tests were carried out under environmental temperatures ranging from +5 °C to +60 °C. The effect of mismatching (12.5% to 37.5% of total cells number) of the cell parameters on the temperature distribution and voltage fading at the terminals of individual cells was checked. As a result of the investigations, the practical usefulness of the developed active BMS was determined, enabling the extension of the lithium-iron-phosphate battery life under onerous mine conditions, for a single recharge, which is a novelty. On the basis of the obtained results, appropriate practical conclusions were formulated.

Lithium-Iron-Phosphate Battery Performance Controlled by an Active BMS Based on the Battery-to-Cell Method

“…However, to evaluate the operation of battery systems with BMS, when they are mounted in a closed housing on suspended vehicle, the tests were also carried out for distorted cooling and at elevated temperature (up to + 60 °C, humidity around 75 %). These studies were carried out in a climatic chamber and the results of the battery sets are presented in [30]. To test the balancing effectiveness of the BMS, an asymmetric loading of completed cells was needed.…”

Energy Management for PV Powered Hybrid Storage System in Electric Vehicles Using Artificial Neural Network and Aquila Optimizer Algorithm

“…where ϕ rα and ϕ rβ are the α and β axes rotor fluxes, respectively. The stator linkages are estimated from the measured stationary α − β reference frame [35]. The stator flux linkage and its vector position are given in Equations ( 20)-( 22):…”

A Joint Estimation Method Based on Kalman Filter of Battery State of Charge and State of Health

“…The Rint model, Thevenin model, and PNGV model are common lithium battery equivalent circuit models. In these models, the Thevenin model is widely used due to its simple structure and good representation of the dynamic and external characteristics of lithium batteries [22]. Therefore, the Thevenin model was selected as the parameter identification model, which has a second-order RC.…”