Life Cycle Assessment of LiCoO2/Graphite Batteries with Cooling Using Dualfoil Simulations and Simulink Modeling

Abstract

Life cycle assessment (LCA) is a tool used to quantify the environmental impacts of various products and processes. Within an LCA, data is generated or collected for each component and/or process across its full life cycle from mining and extraction through production, use, and end-of-life recycling or disposal phases. This data is compiled into an impact assessment that estimates the net effects of the product or process on the world’s ecosystems, human health, and the depletion of natural resources. With an increasing demand for lithium-ion batteries (LIBs) in portable electronics and electric vehicles, there is growing interest in quantifying the environmental impacts of LIB production, use, and disposal. While many recent studies have tabulated specific environmental impacts of LIB components across impact categories and made comparisons of different battery chemistries, to date, there has been relatively little study of the effects of LIB design and operating conditions on the net environmental impacts.The goal of this work is to quantify the extent to which forced air cooling can reduce the global warming potential (GWP), Energy Usage (GWP), and Particulate Material (PM (2.5)) of lithium cobalt oxide-graphite (LCO-C) batteries under various operating conditions. Dualfoil, an open-source first-principles electrochemical modeling program developed by Newman et al. [1], is used to simulate LCO-C capacity and cell temperature as a function of design and operating conditions, including cathode/anode thickness, C-rate, and ambient temperature. Cell temperature is then used to estimate capacity loss of the LCO-C battery, providing an estimate of battery cycle life [2]. Battery cycle life estimates are combined with LCA data to quantify environmental impacts on a per kWh*cycle basis for each impact category. When used in small-scale hand-held consumer electronics, LCO batteries typically function without active cooling, despite the negative impacts on cycle life associated with increased cell temperature. The present study results indicate that integration of a simple fan-based forced air-cooling scheme with LCO-C cells can decrease GWP, energy usage, and PM (2.5) impacts of these devices by as much as half compared (24 kg CO2 eq-per kWh per 1000 Cycles to 12 kg CO2 eq-per kWh per 1000 Cycles) to non-cooled LCO-C batteries [3].[1] “Fortran Programs.” http://www.cchem.berkeley.edu/jsngrp/fortran.html (accessed Feb. 25, 2021).[2] J. Wang et al., “Cycle-life model for graphite-LiFePO4 cells,” J. Power Sources, vol. 196, no. 8, pp. 3942–3948, Apr. 2011, doi: 10.1016/j.jpowsour.2010.11.134.[3] “Simple CPU Cooling System - MATLAB & Simulink.” https://www.mathworks.com/help/physmod/hydro/ug/simple-cpu-cooling-system.html (accessed Jan. 28, 2021). Figure 1