ESCL_에너지저장변환 실험실

Energy Storage Conversion Lab.

Publication

International

A State-of-Charge and Capacity Estimation Algorithm for Lithium-ion Battery Pack Utilizing Filtered Terminal Voltage
Content type 2015
Title of paper A State-of-Charge and Capacity Estimation Algorithm for Lithium-ion Battery Pack Utilizing Filtered Terminal Voltage
Author Chang Yoon Chun, Sung Hyun Yoon, B. H. Cho, Jonghoon Kim
Publications World Electric Vehicle Journal
Status of publication published
Vol 7
Link 관련링크 https://www.researchgate.net/publication/323522616_A_State-of-Charge_a… 43회 연결

In electric vehicle (EV) and hybrid electric vehicle (HEV) application, accurate information of state-ofcharge

(SOC) and capacity of each cell are required for elaborate SOC/capacity estimation algorithm of the

battery pack. However, the measurement of the states of all cells using sophisticated algorithms increases

the computation time beyond practicality, because the computation time required for the SOC/capacity

estimation of the battery pack is directly affected by the number of unit cells. In this work, a simple SOC

and capacity estimation algorithm for Li-ion battery pack is newly proposed by using filtered terminal

voltage. The SOC estimation algorithm using filtered terminal voltage extracts an estimated current

information from the terminal voltage of the battery pack through equivalent-circuit model (ECM)-based

filters without sensing the current. Consequently, it drastically reduces computational steps for the SOC

estimation algorithm. With the fact that all the current flowing through the series-connected cells in pack

are identical, the estimated current value of each cell should be identical. As a result, it can be known that

this algorithm enables us to obtain the relative proportion of SOC/capacity information of each cells and

battery pack with minimal complexity increase. To validate the performance of the proposed approach, a

scaled-down HEV profile is used for a pack consists of twelve 18650 series-connected Li-ion batteries

(12S1P). The experimental results verify the performance of the proposed battery pack SOC estimation

algorithm.