scholarly journals An Enhanced Multicell-to-Multicell Battery Equalizer Based on Bipolar-Resonant LC Converter

Electronics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 293
Author(s):  
Xuan Luo ◽  
Longyun Kang ◽  
Chusheng Lu ◽  
Jinqing Linghu ◽  
Hongye Lin ◽  
...  

In a battery management system (BMS), battery equalizer is used to achieve voltage consistency between series connected battery cells. Recently, serious inconsistency has been founded to exist in retired batteries, and traditional equalizers are slow or inefficient to handle the situation. The multicell-to-multicell (MC2MC) topology, which can directly transfer energy from consecutive strong cells to consecutive weak cells, is promising to solve the problem, but its performance is limited by the existing converter. Therefore, this paper proposes an enhanced MC2MC equalizer based on a novel bipolar-resonant LC converter (BRLCC), which supports flexible and efficient operation modes with stable balancing power, can greatly improve the balancing speed without much sacrificing the efficiency. Mathematical analysis and comparison with typical equalizers are provided to illustrate its high balancing speed and good efficiency. An experimental prototype for 8 cells is built, and the balancing powers under different operation modes are from 1.426 W to 12.559 W with balancing efficiencies from 84.84% to 91.68%.

Energies ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2221
Author(s):  
Omer Faruk Goksu ◽  
Ahmet Yigit Arabul ◽  
Revna Acar Vural

Lithium ion (Li-Ion) and lithium polymer (Li-Po) batteries need to be used within certain voltage/current limits. Failure to observe these limits may result in damage to the battery. In this work, we propose a low voltage battery management system (LV-BMS) that balances the processes of the battery cells in the battery pack and the activating-deactivating of cells by guaranteeing that the operation is within these limits. The system operates autonomously and provides energy from the internal battery. It has a modular structure and the software is designed to control the charging and discharging of eight battery cells at most. A STM32F103 microcontroller is used for system control. The fuzzy logic controller (FLC) is used to set the discharge voltage limit to prevent damage to the battery cells, shorten the settlement time and create a specialized design for charge control. The proposed structure enables solar panel or power supplies with different voltage values between 5 V and 8 V to be used for charging. The experimental results show there was a 42% increase in usage time and the voltage difference between the batteries was limited to a maximum of 65 mV. Moreover, the charge current settles at about 20 ms, which is a much faster response when compared to a PID controller.


2020 ◽  
Vol 1517 (1) ◽  
pp. 012025
Author(s):  
J Raharjo ◽  
A Wikarta ◽  
I Sidharta ◽  
M N Yuniarto ◽  
M I Firdaus ◽  
...  

Abstract The Battery management system (BMS) is a main component in the battery pack system for electric vehicles (EV). The function of BMS is to monitor battery cells such as; cell voltage, cell temperature, and current in the battery pack. Moreover BMS also able to balance the voltage of the cells so the difference in voltage of the cells can be minimized. By having many of these functions, BMS can identify battery health based on these parameters. With such an important function, in this paper, BMS was tested to determine its reliability. The standard testing for BMS reliability is the Environment test. In the environment test, some things that are conducted in the environment test are initial temperature cycling. From the environment, the test can be generated information to assess the quality of the BMS following its function. Furthermore, it can reduce the cost to inspect every battery cells in the packs. With the environment test as a basis for BMS reliability tester, hopefully, good quality is obtained. Future development in BMS reliability testing can also be conducted to improve reliability.


The green energy evolution initiated the use of electric and hybrid electric vehicles at present on roads. These vehicles extensively use different types of batteries and among them lithium ion batteries are prominent. The Li-ion battery pack constitutes number of Li-ion battery cells connected in series and parallel configuration. This battery bank needs a suitable battery management system for its efficient operation. This paper presents a novel battery management system to monitor and control the battery current, voltage, state of charge and most importantly the cell temperature. The detail BMS scheme for Li-ion battery pack is presented and simulation is carried out to validate its performance with a driving cycle of electric car.


2019 ◽  
Vol 53 (1-2) ◽  
pp. 205-213 ◽  
Author(s):  
Sinan Kıvrak ◽  
Tolga Özer ◽  
Yüksel Oğuz ◽  
Emre Burak Erken

In this study, a battery management system was implemented using the passive charge balancing method. The battery system was created with lithium ion battery cells commonly used in electric vehicles. Two main microprocessors were used as a master and slave for the management system. An STM32f103C8 microcontroller was used as a master, and a PIC18f4520 microcontroller was used as slave control units in the battery management system. Charge control of a battery pack consisting of four cells was performed. The information received from the current and voltage sensors was collected from each cell using a slave controller and sent smoothly to the master controller system. These experimental results indicated that the passive balancing method was implemented and the battery cells were charged successfully. The proposed method was applied to battery pack consisting of a four-cell LiFePO4 battery with a capacity of 40 Ah. This work incorporated original situation that have not been realized before. A digital to analog converter circuit was created using a buck converter topology. Thus, the MOSFET was used as an adjustable resistance. Also, it was one of the first studies in which the MOSFET was used as a regulated resistor in battery management systems.


Sign in / Sign up

Export Citation Format

Share Document