Worldwide, there has been an exponential growth in the production and application of lithium-ion batteries (LIBs), driven by the energy transition and the electric vehicle market. The scarcity of raw materials and the circular economy strategy of LIBs encourage the need to reuse components, recycle, and give second life to used batteries. However, one of the obstacles is the insufficient volume of LIBs for recycling, which prevents the economic viability of this industrial process. Thus, this article mainly focuses on the economic aspects of the recycling of LIBs, presenting and analyzing: (i) the advantages and disadvantages of recycling and (ii) a survey of factors that influence the cost and economic feasibility of disposing of batteries. The importance of regulations, the market, and business models regarding the recycling of LIBs in a few countries are also discussed. Finally, a business model is created for recycling LIBs in Brazil. The main factors that influence the economic feasibility of this process are indicated, such as government incentives through regulation, exemption from fees and taxes, and the adequacy of battery technology. Encouraging recycling through tax exemptions or reductions can make the process more economically viable, in addition to contributing to the circular economy. Another essential factor to be considered is the creation of joint ventures, which can facilitate the entire chain of the circular economy, including logistics, transport, and disposal of batteries.

The insertion of renewable sources to diversify the energy matrix is one of the alternatives for the energy transition. In this sense, Brazil is one of the largest producers of renewable energy in the world, mainly in wind generation. However, the impact of integrating intermittent sources into the system depends on their penetration level, causing problems in the electrical network. To evaluate this scenario, the present article aims to investigate the power quality problems generated by wind turbines in connection with the electrical system and how battery energy storage systems (BESS) solve or mitigate these disturbances in the network. Knowing the impacts of high generation power variability, the focus of the work is the application of power smoothing. However, results are presented for five applications (factor correction, voltage control, power factor smoothing, frequency control and time shift) that can be carried out at the studied wind farm. This article presents a real BESS, which has a capacity of 1 MW/1.29 MWh, connected in parallel to a group of wind turbines that provides a power of approximately 50.4 MW located in Brazil. In addition to presenting the system simulation in HOMER Pro software, this study validates the effectiveness of this BESS by presenting real operation data for each application.