Battery cell ragone plot is power density vs energy density. A plot often used to compare chemistry.
This plot needs to consider peak versus continuous power. The following plot is from the Cell Database. Note: as this is specification sheet data and the energy content is not established at the given discharge rate it is not a true Ragone Plot.
In this plot we can just about see a trend that higher energy density => lower power density. Although with a mix of cell chemistry and cells from 1991 to present this is blurred to some extent.
Hi Nigel, I also like to evaluate lithium-ion cells (lithium-ion batteries) basing on Ragone plots. We have summarised Ragone plots for lithium ion cells used for different applications in our book: Lithium-Ion Cells: Materials and Applications, may be downloaded free of charge from MDPI web-site.
Link to the free download here: https://www.mdpi.com/books/monograph/9937-lithium-ion-cells-materials-and-applications