An improved Ampere-hour method for battery state of charge estimation based on temperature, coulomb efficiency model and capacity loss model

Author

Wu, Guoliang ; Lu, Rengui ; Zhu, Chunbo ; Chan, C.C.

Author_Institution

Dept. of Electr. Eng., Harbin Inst. of Technol., Harbin, China

fYear

2010

fDate

1-3 Sept. 2010

Firstpage

1

Lastpage

4

Abstract

Coulomb efficiency and available capacity affect the precision of Ampere-hour method. Both coulomb efficiency and available capacity vary with temperature and discharge current rate. In this study, some experiments of a 27Ah Nickel Metal Hydride battery were undertaken to determinate the coulomb efficiency. These experiments were undertaken at -18°C, -12°C, 0 °C, 25°C with 1/3C, 1C, 3C charge rate and 1/3C discharge rate. Then, an improved coulomb efficiency model was proposed, which is based on temperature and charge rate. Moreover, an available capacity loss model was built based on experiments of 1/3C discharge rate at -18°C, -12°C, 0°C, 25°C. In addition, an improved Ampere-hour method based on temperature, coulomb efficiency and capacity loss model was built to estimate battery state of charge. The proposed method is verified by experiment and the result shows good precision.

Keywords

battery charge measurement; secondary cells; 27Ah nickel metal hydride battery; Coulomb efficiency model; Ni; ampere-hour method; battery state; charge estimation; discharge current rate; temperature -12 C; temperature -18 C; temperature 0 C; temperature 25 C; Batteries; Discharges; Electric vehicles; Estimation; Nickel; System-on-a-chip; Ampere-hour; Nickel Metal Hydride battery; available capacity; capacity loss; coulomb efficiency; state of charge; temperature;

fLanguage

English

Publisher

ieee

Conference_Titel

Vehicle Power and Propulsion Conference (VPPC), 2010 IEEE

Conference_Location

Lille

Print_ISBN

978-1-4244-8220-7

Type

conf

DOI

10.1109/VPPC.2010.5729017

Filename

5729017