车用钛酸锂电池生命周期评价

摘要

In order to evaluate the impacts on energy, environment and resources arose from the lithium titanate batteries used on electric vehicles, firstly a life cycle assessment model for the Li-ion batteries were established, which included the re-purposing and second-use stages. Then a lithium titanate battery pack made by a domestic enterprise, which was used on an all-electric city bus, was chosen as the study case. And its life cycle CED (cumulative energy demand), GWP (global warming potential) and ADP(e) (abiotic depletion potential for elements), as the three major indicators of impacts, were calculated. The results showed that the CED, GWP and ADP(e) for every kilo-watt hour capacity of the battery pack in its life cycle were 2.8×104MJ, 1.86×103kg CO2eq. and 4.77×10-3kg Sbeq. respectively. It was found that the energy loss due to the battery efficiency in both use stages had played the key role in battery's life cycle GWP, while GWP of the producing stage mostly came from the embedded greenhouse gas emissions of raw materials such as the cathode and anode materials, aluminum parts and N-methyl-2-pyrrolidinone. From the perspective of the energy stored and delivered in its life cycle, the LTO battery's GWP per every mega-Joule would decrease significantly with the second-life usage, and GWP of its producing stage is the lowest among all of the Li-ion batteries in the comparison with previous studies.%为评估车用钛酸锂(LTO)电池对能源、环境与资源的影响,构建了包括重制与二次使用阶段在内的车用锂电池全生命周期评价模型,以某款国产纯电动客车用钛酸锂电池包为评价对象,计算得出每kW·h钛酸锂电池全生命周期的总能量消耗(CED)、全球变暖潜值(GWP)和不可再生矿产资源耗竭潜值(ADP(e))分别为2.80×104MJ、1.86×103kg CO2eq.以及4.77×10-3kg Sbeq.其全生命周期CED与GWP主要与两个使用阶段中由电池充放电效率引起的能量损耗相关,生产阶段GWP主要来源于正负极材料、铝制材料和N-甲基吡咯烷酮.基于全生命周期存储-释放每MJ能量的视角,发现二次使用可显著降低电池全生命周期GWP;与已有研究中其他锂电池对比可知LTO电池生产阶段GWP最低.