Economic analysis of CNT lithium-ion battery manufacturingElectronic supplementary information (ESI) available. See DOI: 10.1039/c5en00078e

Development of safe, economically competitive, and environmentally responsible nano-enabled products is desirable to avoid unintended consequences. Given the environmental health and safety uncertainties associated with nanomaterials, additional precautions for exposure prevention may be required, although not regulated. Companies working with engineered nanomaterials may want to understand decision tradeoffs for the costs associated with increased levels of occupational safety and potential environmental impacts. Recent advances in nanotechnology have resulted in the development of advanced lithium nickel manganese cobalt (NMC) oxide batteries enhanced with multiwall carbon nanotubes (MWCNT). These batteries have a much greater energy density and product life than traditional lithium-ion batteries. A stochastic process-based cost model (PBCM) is developed to investigate the cost drivers for manufacture of MWCNT NMC batteries targeted for satellite and computer applications. Various levels of occupational safety protection (low, medium and high assumed) are analyzed to determine their effect on total manufacturing cost. The results show that MWCNT cost has the highest impact on total unit cost for production of satellite batteries, whereas cycle time has the highest impact on the unit cost of computer batteries. The mixing step contributes the most to the total unit cost for both satellite and computer MWCNT NMC lithium-ion batteries due to the inclusion of MWCNT costs in the mixing step. The process-based cost model developed in this work not only offers estimation of the economic drivers associated with the MWCNT NMC battery manufacturing, but also allows consideration of strategies to reduce costs. Results contribute to safer manufacturing practices for CNT lithium-ion batteries for low and high production volume applications (satellites and portable computers, respectively). Although MWCNT lithium battery costs increase when proactively preventing manufacturing worker exposures, costs per unit of specific energy decrease overall.