Li-ion batteries (LIBs) are the most commonly used energy storage technology in various consumer goods, including electric vehicles. However, several alternatives, so-called beyond-LIBs, are greatly investigated to decrease battery costs using abundant and globally distributed materials with high theoretical capacities. Among the diverse beyond LIB systems, this paper includes the top 6 researched chemistries: univalent (Na- and K-) and multivalent (Zn-) metal-ion, metal-air (Li-air and Zn-air), and Li-S batteries. Naturally, all these six battery chemistries have problems that must be addressed before mass commercialization. Although there are 24,523 publications on these batteries, a parallel examination of these technologies to transfer knowledge must be included in the literature. This study used text mining analysis to study the most common keywords and word connections for beyond-LIBs to learn from the general trends in the literature [1].First, the dataset was built using the Web of Science database in June 2023 by applying all the possible alternative names of beyond LIBs in the search with the Title option. Hence, the abstracts, author keywords, and keywords plus for each battery chemistry were obtained together with the article information. Afterward, data cleaning and text mining analysis were performed using the R Studio environment, specifically stringr, tm, pluralize, and tidytext libraries. The research interests in the primary battery parts and the single material-related words and two-word bigrams were investigated.The bibliometric analysis has shown that Li-S and Na-ion batteries are the most popular research areas in the beyond LIB literature. On the other hand, interestingly, Li-air batteries lost their popularity to Zn-air in around 2015. Publications on Zn-ion batteries have a sharp increasing trend, and K-ion batteries have started to share this research interest. When the single-word results are analyzed, it has been seen that anode, cathode, and electrolyte are the most commonly studied battery sections for Na- and K-ion, Zn-ion and Li-S, and finally, Zn- and Li-air batteries, respectively. Apart from the battery parts, regardless of the chemistry, the high frequency of carbon and graphene keywords are detected; hence, bigram analysis is further performed on these keywords to see the most associated words with these materials. It has been seen that carbon nanotubes are the first and nanofibers are the second preferred form of carbons, whereas the graphene oxides are found to be promising for all beyond LIBs, given only good results are reported in the literature.
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