As mentioned in a previous blog, charging strategies have a significant impact on battery longevity and market perception, which heavily effects the market’s overall perception of a brand.
Depending on the complexity of a charging strategy, it may require optimization, or calibration. is extremely difficult, expensive, and time consuming. Intuitively, this is true because of the time and cost associated with physical testing. Less intuitively, however, this is also true because experimental testing of Li-ion cells can only measure voltage, current, and temperature of the cell or battery; whereas, understanding the true impact of a charging strategy requires much more detailed information about the state of the battery.
Luckily, physics-based modeling of Li-ion cells using GT-AutoLion enables engineers to have insight into the electrochemistry inside Li-ion cells well beyond voltage, current, and temperature measurements. This ultimately enables charging strategies to be virtually calibrated.
GT-AutoLion not only calculates the high-level quantities of Li-ion cells like voltage, current, and temperature, but also hundreds of other physical quantities within the cell, allowing engineers to have valuable insights into the electrochemistry of the cell. With this ability, GT-AutoLion enables engineers to explore, calibrate, and make robust decisions for fast charging algorithms early in a development cycle, enabling less physical testing to be done and when physical testing needs to be done, the tests are better informed and more focused.
Thanks to a discretization of the anode, separator, and cathode in a one-dimensional manner, GT-AutoLion solves for many quantities throughout the thickness of the cell. For instance, the electrical potential of the electrolyte and the concentration of Lithium-ions throughout the thickness of the cell are solved for on a location-dependent and time-dependent manner, as shown in the image below, which summarize the results of an example 1C discharge event (Left) and a 1C charge event (Right). These quantities help give insight into electrochemical performance within the cell. The potential in the electrolyte at various times is represented in the top plots and the concentration of Lithium-ions at various times is represented in the bottom plots.