Research On The Whole Life Cycle Of Ternary Lithium-ion Power Battery Syste

Promoting the use and development of electric vehicles is an effective way to reduce resource consumption and emission pollution and move towards sustainable development.However,the production of electric vehicle power battery systems consumes a variety of mineral resources and primary energy and is accompanied by the generation of a large amount of greenhouse gases and other pollutants.The resulting resource and environmental problems are serious obstacles to the further development of the lithium-ion electric vehicle industry.Currently,China is a major producer and user of new energy electric vehicles.Carbon neutrality has become an important goal for the development of new energy vehicles in the country.However,the resource and environmental assessment system related to power batteries is still in its infancy and has not yet been perfected.Therefore,it is very necessary to conduct a full life cycle assessment of lithium-ion power batteries for vehicles to establish a resource and environment assessment system in the country.This paper summarizes the current domestic and foreign developments of life cycle research and establishes the research purpose and significance of this paper by researching electric vehicles and lithium-ion batteries for the whole life cycle.Taking the 124Ah,42.2k Wh ternary power battery system of a certain model as the research object,the battery system is mainly subdivided into four stages:the main component production stage,the material transportation stage,the battery use stage,and the recycling stage.The processing technology of the most upstream components is stipulated within the system boundary of the life cycle assessment system.Using the cut-off criterion,the manufacturing of a complete lithium-ion power battery system is taken as a functional unit to collect,organize,and process data such as resource consumption,energy use,and process emissions.The data is analyzed and calculated,and the modeling of the process operation unit is completed on SimaPro.The carbon footprint of the entire life cycle is analyzed according to the model,and the Impact 2002+and CML-IA baseline evaluation methods are used to carry out resource and environmental impact assessments of the ternary lithium-ion battery system.Finally,the recycling processes are evaluated and compared.Studies have shown that the carbon footprint of the ternary lithium-ion battery life cycle is mainly concentrated in the use and production phases of the battery,accounting for 78.9%and 19.9%respectively.The production of positive electrode materials in the production phase can produce 6.16t equivalent CO₂.In the Impact2002+evaluation method,the potential values of 9.18mpt,3.63mpt,5.34mpt,and 3.93mpt were generated in the four endpoint damage categories of lithium-ion battery life cycle human health,ecological quality,climate change,and resource consumption.Human health in the use stage is the largest source of negative effects,with a potential value of 4.44mpt.The potential value of human health in the production stage and the potential value of climate change in the use stage are 3.37 mpt and 3.33 mpt respectively,and the potential value of human health and resource consumption in the recycling stage is-0.96mpt and-0.72mpt.It shows that the recovery stage has produced a good positive effect.In the CML-IA baseline evaluation method,the life cycle of ternary lithium-ion batteries is analyzed from two aspects of abiotic depletion and environmental impact.The depletion of non-biological mineral resources and fossil energy depletion is respectively 1.7E-01kg Sb·eq and 4.3E+05MJ.The impact of acidification on the environment is 7.1E+02kg SO₂·eq,human toxicity is 1.0E+04kg 1,4-DCB·eq,aquatic ecotoxicity.Using two evaluation methods,the environmental impact of the three recovery processes of wet chemical precipitation,wet extraction,and dry recovery are comprehensively compared.It is concluded that the dry recovery process had the greatest impact,followed by the wet chemical precipitation process,while the wet extraction process had the least impact.