Better Batteries

Rechargeable batteries using lithium ions are everywhere; you probably have one in your pocket or bag right now! Their light weight and high energy density means they are the best option for many portable devices, phones, electric vehicles and aerospace applications.

However, they can have limited lifetimes of a couple of years and, as they get older, they hold less and less energy with each recharging cycle. We need to improve this to get better batteries.

Using tomography at Diamond, with our collaborators at the University of Cambridge and UCL, our group is looking inside working batteries at microscopic scales, whilst they are actually in use, to study the reactions and structural changes that limit their power.

Microscopic Moss
Our 4D science shows how microscopic structures of solid lithium that look like moss or trees can form inside the batteries. These beautiful but harmful structures, known as dendrites, can damage batteries and cause short circuits inside.



Microscopic, tree-like structures, hidden inside operating batteries, have been observed for the first time with Diamond tomography.




Travelling Trees
By watching these tiny trees grow and move within the battery over time we can understand how they can be controlled. We hope to use this knowledge to improve battery lifetimes and safety.

Using Diamond we can watch the dendrite structures, which are harmful to battery life, grow bigger and more dense over time.