Come up with concrete examples of what design optimisation actually looks like using battery models

[davidhowey]

To make the challenge more tangible we should think of some examples of how battery models might be optimised from a design point of view and code these up in PyBOP. Example previous study

[davidhowey]

Some thoughts on this from the excellent @scro2542: 'The energy density of an electrode is roughly proportional to the amount of active material there. So to increase energy we can either cram more active particles in or make the electrode thicker. But doing so causes greater electrochemical gradients through the electrode thickness to drive the diffusion. Energy-dense electrodes then become poor at high C-rates and have accelerated degradation. This is an unavoidable trade-off. The problem then becomes either: "Can we set-up the cell of a given energy density (e.g. electrode thickness, amount of calendering, % of carbon) so that it achieves the required C-rate performance/degradation"? Or: "Can we optimise the local electrode microstructure, e.g. through controlled drying or Patrick's spray process, to improve the C-rate/degradation performance for a given energy density? For the 2nd question, one has to be careful to think about understanding what can be controlled experimentally. The optimal design suggested by the optimiser should be "realisable" in practice using standard equipment.'

[NicolaCourtier]

To date, we have added two example design costs: one for the gravimetric energy density and another for the volumetric energy density. These are based on the example study mentioned above.

I believe our gravimetric energy density example addresses one of @scro2542's suggestions, as it optimises the energy density calculated from a CC discharge with respect to geometric parameters such as electrode thickness and particle radius.

Suggestions of further design optimisation examples are very welcome, although it is worth noting that optimising manufacturing parameters is currently out-of-scope due to the lack of manufacturing models.

[BradyPlanden]

Closing this issue as @NicolaCourtier mentions above. Feel free to open a new issue with more specific outcomes.