CellMod is based on Newman’s pseudo-2D lithium ion electrochemical model (the most widely used lithium-ion battery model of this type). The model dependent variables are the concentration of active ions across the electrolyte, the concentration of reducing agents on the surface and within the solid particles, the electrical potential across the solid electrodes, the electrical potential across the electrolyte and the local reaction rate.

The model is coupled with Sendyne’s proprietary dtSolve, a tool that executes several orders of magnitude faster than other commercially available numerical solvers. A simple API allows any simulation platform to provide inputs and read the outputs of the model.

The software may be used as a standalone tool or can be integrated with other simulation packages for whole system co-simulation via the Functional Mockup Interface (FMI), an open standard supported by all major simulation platforms.

CellMod can be quickly adapted to represent any type of Li-Ion cells, from NMC and LMO to LFP and NCA, and all iterations of these cells. To achieve this, only a simple (non-proprietary) set of experimental data on the cell to be modeled is needed. Sendyne’s tool kit, which includes state of the art parameter extraction, then creates a unique CellMod version for a specific cell. All unique CellMod versions are created under NDA.

Currently deployed by a Tier-1 US battery maker, CellMod’s uses include battery cell rapid prototyping. This reduces design time and costs, as each cell design can first be tested using the model. Design makers can utilize the model to select cells and vendors based on how well candidate cells perform in particular applications.

Further, CellMod can help reduce cost—a major challenge to large scale battery adoption. The compact nature of the CellMod-dtSolve bundle allows it to be embedded on a microcontroller within a Battery Management System (BMS) for real time predictive control.

For large-scale battery systems, such as those used by electric vehicles and energy storage systems, multiple instances of the model, equal to the number of cells in the pack, can run simultaneously in real time. Little computing power or memory is required. By replacing the typical empirical models/Kalman filters with a highly accurate model enabling true predicative control, pack safety can be greatly improved and costs due to over-design can be eliminated.

Resources

• M. Doyle, T. F. Fuller, J. Newman (1993) “Modeling of Galvanostatic Charge and Discharge of the Lithium/Polymer/Insertion Cell,” J. Electrochem. Soc. 140 (6) 1526 doi: 10.1149/1.2221597