Evaluation of lithium-ion batteries through the simultaneous consideration of environmental, economic and electrochemical performance indicators

When Lithium-ion Batteries (LIBs) are claimed to be ‘green’ they should not only exhibit outstanding electrochemical performances but also have a relatively lower environmental impact and attractive prices and benefits. From this point of view, we establish a comprehensive LIB evaluation system based on a multi-layer index and provide a comprehensive method for evaluating battery performance. The assessment system considers three aspects: environmental impacts, economic parameters, and electrochemical performances, with several indicators for each aspect. We use the footprint family of indexes to characterise the environmental impact of the battery. We analyse the comprehensive performance and evaluate the size of the market competitiveness with quantitative comparisons of the scores for each battery. A comprehensive assessment system with eleven indicators relating to the three aspects is built. As the indicators have different dimensions and units, we use a calculation method called entropy weight to normalise and nondimensionalise the indices; thus, a comprehensive evaluation value for each sample battery could be achieved. To realise the assessment system with practical samples, we choose four kinds of cathode materials for lithium-ion batteries, including LiFePO₄/C, LiFe_0.98Mn_0.02PO₄/C, FeF₃(H₂O)₃/C and LiMn₂O₄/C, as study objects, and the average values of the comprehensive evaluation indexes for the four battery samples are0.034, 0.041, −0.027, and 0.052, respectively. The lower the comprehensive evaluation value is, the better the performance of the product will be. The FeF₃(H₂O)₃/C battery has the best performance when combining 1 kg of battery cathode material. The results reflect the advantages and disadvantages of different types of battery in terms of processing, cost and environmental performance. The establishment of a comprehensive evaluation system for lithium-ion batteries is not only conducive to the scientific evaluation and optimisation of the wide variety of battery materials that are currently available but also to discovering battery materials with more competitive market prospects. The application of this system is not limited to batteries.