Supercharged the Future: Energy Materials, Batteries and Solar Technologies

Overview

This talk from the Royal Institution surveys energy materials and their role in storage and conversion, with a focus on lithium ion batteries, new cathode chemistries, sodium ion and solid-state alternatives, and advances in solar photovoltaics using perovskites. The lecturer blends experimental context, crystal chemistry, and high level modeling to explain how materials science drives the energy transition.

Key insights

• Lithium ion batteries have propelled portable electronics and EVs, but cobalt in cathodes raises supply, cost and ethical concerns
• Modeling and AI help bridge scales from atomic diffusion to device performance, guiding material discovery
• New cathode chemistries such as lithium rich layered oxides enable higher energy density and use more abundant elements
• Perovskite solar cells show rapid efficiency gains and, in tandem with silicon, offer high efficiency and potential stability improvements

Context and Core Theme

The lecture situates energy storage and solar conversion as central to the contemporary energy landscape, emphasizing the need for new materials and a deep underpinning science. It uses crystal chemistry and ion conduction as a thread to connect the performance of batteries with future energy systems and solar technologies. The presenter argues that breakthroughs require synthesis, measurement, and predictive modeling, including machine learning to bridge scales from atoms to devices.

Materials and Methods

The speaker outlines a materials science workflow: synthesize compounds, characterize them, and think about manufacturing and scale up. Modeling plays a critical role across scales, from atomistic diffusion to electrode microstructure and device-level performance. AI is presented as a tool to learn from high-fidelity data and to enable faster exploration of materials combinations, while still requiring human expertise to avoid garbage in garbage out.

Lithium Ion Batteries: What’s Inside and What’s Next

The battery is described as a sandwich: a graphite anode and a layered cobalt oxide cathode with lithium ions shuttle between layers. Cobalt is highlighted as expensive, toxic and ethically problematic, driving interest in cobalt-free alternatives such as lithium iron phosphate and nickel manganese cobalt oxides (NMC) with reduced cobalt content. The talk then introduces lithium rich layered oxides and disordered rock salt materials that push energy density higher, potentially approaching the energy density of the graphite anode. A key concept is oxygen redox, where oxygen ions participate in charge storage, promising higher energy density but presenting stability challenges that must be overcome through materials design and processing strategies.

Lithium Diffusion and Future Cathodes

Modeling reveals diffusion pathways in these materials. In lithium cobalt oxide, diffusion is straightforward along layered structures, while in lithium iron phosphate the diffusion path is curved and one-dimensional, which has implications for ion mobility and rate capability. Collaboration with neutron diffraction experiments confirms these curved 1D diffusion pathways. The vertical axis of the talk shows energy storage capacity, illustrating the gap between current cathode materials and the anode, thus motivating ongoing cathode development and the exploration of oxygen redox materials to raise energy density while balancing stability and sustainability.

Beyond Lithium: Sodium Ion and Solid State Options

The discussion moves to sodium ion batteries due to the abundance of sodium and its potential for cost reduction, especially for grid storage and some e-scooters. The lecturer also highlights solid state batteries as a safer alternative with the potential for higher energy density when using a lithium metal anode, albeit with challenges in ion transport across solid electrolytes. A demonstration of reactive alkali metals is used to illustrate chemical reactivity with water as a teaching aid. The talk emphasizes the need for safer, scalable solutions as part of the 3R framework: reduce cobalt, reuse and recycle materials through better design and policy.

Solar Energy: Perovskites and Tandems

In the solar section the lecturer contrasts silicon with perovskite absorbers, noting that perovskites rose rapidly from low efficiency to exceed traditional silicon in a short period. Perovskites are described as organic-inorganic hybrids with a movable organic cation in an inorganic framework, which contributes to high absorption and tunable bandgaps. Stability remains a major hurdle, limiting long-term deployment. Tandem cells combining silicon and perovskite offer a path to efficiencies beyond single-junction silicon and can mitigate some stability concerns by leveraging complementary absorption. The talk also references Oxford PV and industry advances toward manufacturing and scale up for tandem devices.

Global Context and the Energy Transition

The speech places energy storage and solar in a broader context of climate policy, energy security and growing demand in emerging economies. It presents data on electric vehicle adoption and solar deployment to illustrate the upward trajectory of the energy transition and emphasizes the importance of recycling and sustainable sourcing for critical battery materials. The closing remarks stress optimism, the role of scientists in addressing global challenges, and the importance of feedback from students and the public to guide future work.

Conclusion and Reflections

The lecturer closes by emphasizing the need for continued innovation in energy materials and the value of interdisciplinary collaboration, modeling and policy for accelerating the transition. The talk ends with thanks to the research group, funders, and the audience, and a light note on the importance of feedback for continuous improvement in science communication.