Abstract

Since the invention of the Li ion battery more than 40 years ago there have been steady improvements in LIB performance, such as energy and power density. However, the most dramatic change has been the reduction by more than an order of magnitude in the cost per unit energy stored due to manufacturing innovations. LIB prices are continuing to reduce, albeit more slowly, but battery performance is beginning to stagnate, disappointingly well-below the intrinsic energy storage performance of the active cathode and anode materials. The cause of the performance plateau is the ubiquitous method of manufacturing the electrodes, which although highly productive and cost-effective, constrains the range of electrode structures possible – and therefore performance that can be achieved.

This talk explores how to configure conventional, widely available energy storage materials into different structural arrangements and examines if and why these changes can deliver useful benefits, and under what conditions benefits might be maximised. The electrochemical response of these deliberately heterogeneous electrodes is complex and so models are used in conjunction with experiment to unpick and understand the underlying physical behaviour. With this knowledge, such models are on the cusp of being able to design rationally electrodes structures that produce an optimised electrochemical response against a set of performance requirements. However critical to realising hetero- or smart electrodes in practice are manufacturing approaches that provide sufficient finesse in microstructural control. Several examples will be described including various graded electrodes, layered electrodes of two different active materials, novel binder arrangements, and interlayers in solid-state batteries.