State Of Health Detection System Of Lithium-ion Battery Based On Differential Voltage Analysis Method

Petroleum,coal and natural gas are limited reserves of fossil energy,and some energy will release various substances during their working process,resulting in greenhouse effect and environmental pollution.The rational use of all kinds of energy and energy storage and utilization,is a difficult problem for all relevant researchers.At present,lithium batteries are widely used in all kinds of electronic equipment,instruments and even electric vehicles.In order to ensure the stability of operation and using safty of these devices,it is very important for the performance detection and SOH(state of health)analysis of lithium-ion batteries.After eliminating the self-heating interference of the lithium battery,the method of estimating the SOH of lithium battery by detecting and analyzing the voltage change rate of lithium battery is put forward,based on the analysis of the electric charge performance parameters of lithium battery and combined with the analysis of the influence of the self-heating of lithium battery,As for the detection of lithium-ion battery state of health,this paper mainly studied the following contents.(1)By analysis of the working mechanism and the mechanism of aging reaction of lithium-ion battery,the differential voltage of lithium-ion battery is selected as the characterization parameter of the detection of SOH according to the principle of easy measurement and characteristic.Then we put forward the system implementation scheme.(2)By the detection of voltage,current and discharge power in the process of lithium-battery group discharging and the analysis of the result of the test,the correlation between the voltage change rate and the SOH of the lithium-ion battery group is obtained.After fitting the data curve,the relation curve of the voltage change rate and the SOH of the lithium-ion battery are obviously showed.(3)We designed the hardware circuit of the lithium-ion battery SOH detection system based on the ARM+MAX17830 chip architecture,and programed the corresponding data detection software program.In addition,a Qt5 based SOH detection and analysis PC program for lithium-ion batteries was completed.(4)By using the relational curve above and the hardware with software programs designed in the paper,the overall function of the system is completed.With the analysis and display of the upper computer program,the value of SOH of the lithium-ion battery group can be analyzed and tested.