Towards a Better Understanding of Batteries: Manufacturing and Modeling Using Comsol

High energy lithium (Li) batteries are fast becoming a promising energy market for applications in the automotive and portable power markets. In the search for better specific energy and lower cost to manufacture the batteries, novel methods are being researched to overcome the design and operational entices before becoming commercially viable. One of these methods to achieve the above said goals is to manufacture the cells and compare the manufactured cell with its model using COMSOL Multiphysics. This paper proposes battery cell manufacturing and laboratory level testing combined with advance modeling techniques to obtain a correlation for the cell life and stability characteristics data obtained by both simulation and manufactured cell. The batteries are made in the laboratory using the proven and tested methods and the cells are assembled after performing detailed analysis on the surface area and BET analysis of the electrodes. The cells are modeled in COMSOL Multiphysics to estimate the cycle life and stability and to check whether the simulated data is the same as the estimated data. This latter model is then used to check the performance of the cell. The COMSOL simulations are done for different cells and the data is compared with their respective manufactured cell data. The cells are prepared using various available electrode materials and extensive study is carried out regarding the assembly and manufacturing. Preliminary tests of cathode electrode half cells using lithium iron phosphate (LFP) have achieved good results and the theoretical and practical specific capacities are similar as shown in Figure 1. We are able to achieve the specific capacity of LFP half-cell close to 135mAh (densified) as compared to the theoretical capacity of 155mAh. The cells should show similar charge discharge performance when modeled in COMSOL and achieve the similar results when the cells are tested. The results are discussed and recommendations made on battery dimensioning using the specifications observed. Figure1: Figure 1