Life Cycle Assessment On A Specific BEV With Different Power-batteries

With the deepening of energy and environmental issues,the global automotive industry is undergoing a revolution towards the new energy era.The "Three-Year Action Plan for the Battle of the Blue Sky" proposes that China will achieve 2 million new energy vehicle production and sales in 2020 and further increase the proportion of new energy vehicles.China is a big country in the development of new energy automobile industry,ranking first in the world in terms of quantity,production and sales.In this context,the all-round and multi-angle assessment of life cycle resources and environmental emissions of new energy vehicles is more and more essential to lock in the key points affecting the performance of energy-saving and emission reduction of new energy vehicles.What is more,it is helpful to guide the green design and the healthy and sustainable development of energy vehicles in the future.This study summarizes the research results of the current life cycle assessment of new energy vehicles and establishes the research purpose and significance of this paper.The BYDe5 electric vehicle was selected as the research object,and the process of preparing lithium salt and cathode material in salt lake was integrated into the boundary of the whole life cycle assessment system of it by longitudinal extension method.The life cycle is divided into a raw material acquisition phase,a manufacturing assembly phase,a running use phase,and a scrap recycling phase,and a mathematical matrix model is established in stages.The vehicle was further subdivided into seven parts: power battery,electric control device,reducer,drive motor,body,chassis,liquid and fluid.Through literature review and interview research,the relevant materials,energy,manufacturing processes and other data are collected,and the output mineral resources,fossil energy and environmental emission inventory are obtained through calculation.Data processing and result analysis were performed using the CML2001 evaluation method.In addition,single factor sensitivity analysis was carried out with battery charging efficiency,100 km power consumption and energy consumption during the manufacturing assembly phase as sensitivity factors.Furthermore,the evaluation of the life cycle energy-saving and emissionreduction performance of the whole vehicle under the three power batteries of pure electric vehicle matching lithium iron phosphate battery,ternary lithium battery and lithium manganate battery were carried out,and the comparison results were obtained.The research shows that the comprehensive value of fossil energy consumption and environmental emissions during the operation phase of BYDe5 pure electric vehicles is significantly higher than the other three stages of the life cycle(raw material acquisition stage,manufacturing assembly stage,scrap recycling stage).The raw material acquisition stage is accompanied by a large amount of material consumption,and has the largest value of mineral resource consumption.Sensitivity analysis shows that the charging efficiency of a pure electric vehicle power battery has the largest sensitivity factor(0.67).Under different power battery technologies,pure electric vehicles have the highest resource exhaustion and environmental emissions when matching lithium iron phosphate power batteries.The high energy density of the ternary lithium battery itself makes the vehicle produce the minimum energy consumption and environmental emission value.Therefore,the ternary lithium battery should be the first choice in the future green design and component matching of pure electric vehicles.In addition,we should rationally optimize the structure of China's power grid,improve the charging and discharging efficiency of power batteries,and start all-round green production and manufacturing from the source manufacturing technology of power batteries,which will play a key role in the future development of energy-saving and emission reduction of pure electric vehicles in China.