Page 296 - Materials Chemistry, Second Edition

14.3 Methods 295
14.3 Methods

The framework of life cycle sustainability assessment for the prioritization of electrochem-
ical energy storage is introduced in Section 14.3.1; secondly, the Bayesian BWM method for
life cycle sustainability criteria weight determination is presented in Section 14.3.2; finally, the
fuzzy TOPSIS method for sustainability ranking of different electrochemical energy storage
technologies from the perspective of life cycle is presented.

14.3.1 Life cycle sustainability assessment framework
The life cycle sustainability assessment framework for the prioritization of electroche-
mical energy storage aims to rank the comprehensive performances of different electrochem-
ical energy storage technologies and then select the best one based on economic, social,
environmental, and technological aspects. This framework can be divided into three stages,
which are:

Stage 1: Build the criteria system and determine the criteria value. The criteria system
needs to be built from the life cycle sustainability perspective. According to Section 14.2,
the criteria system of the life cycle sustainability assessment for electrochemical energy
storage includes four pillars, namely economy, society, environment, and technology,
which consist of eight criteria. The LCA, LCC, and SLCA can be used to collect the criteria
value in environmental, economic, and social aspects, respectively. Different from the crisp
numbers used by the traditional LCA, LCC, and SLCA, the triangular fuzzy number will be
used to value the criteria, which can address the uncertain issue related to criteria value.
Stage 2: Determine the criteria weights for life cycle sustainability assessment. The latest
MCDM method, Bayesian best-worst method (BBWM) (Mohammadi and Rezaei, 2019),
which can consider the opinions and judgments of multiple decision-makers, is employed
to determine the criteria weights of life cycle sustainability assessment for the prioritization
of electrochemical energy storage from group MCDM view. Meanwhile, the BWM is more
convenient and easy to operate compared with AHP (Rezaei, 2015).
Stage 3: Rank the life cycle sustainability of electrochemical energy storage technologies.
The fuzzy TOPSIS method, which can consider the uncertainties of criteria data, is
employed to rank and prioritize the life cycle sustainability of electrochemical energy
storage.

14.3.2 Criteria weights determination using Bayesian BWM
Best-worst method (BWM) is a new pairwise comparison-based MCDM method (Rezaei,
2015; Rezaei, 2016). It only needs 2n 3 pairwise comparisons, while the most popular
pairwise comparison-based MCDM method, AHP, needs n(n 1)/2 pairwise comparisons.
For BWM, the decision-makers firstly select the best criteria and the worst criteria, and then
compare them with other criteria, not performing pairwise comparisons between any two
criteria. This gives a structure to the problem and can help decision-makers provide more
reliable pairwise comparisons (Guo and Zhao, 2017). However, the BWM determine the op-
timal weights of a set of evaluation criteria based on the preference of only decision-maker or
stakeholder, which cannot consider the opinions of multiple decision-makers. If there are