The topic of battery technology is gaining massive interest to the general public, partly due to the increasing amount of impact it has on our life?s. Almost everyone has one type of consumer electronics with a rechargeable battery, and more and more people are now making the transition towards electrical vehicles (EV).
There is a motivation to improve batteries further to increase the time between charging, and thereby increase the driving distances for EV to get more people to switch out their fossil fuel-based vehicles. This project will achieve this by increasing the overall energy density of the batteries by developing thicker electrodes. The main idea is by increase the amount of active material (electrode material) vs. inactive material (current collector, casing etc), the overall energy per battery mass will increase. There are of course many challenges with this idea. One of the main concerns are related to proper transport properties throughout the electrode material to facilitate reasonable charging times without significant degradation. In MoreIsLess, we aim to solve this through by combining modelling, morphology design and advanced characterisation of electrodes and cells.
Li-ion batteries (LIBs) are currently considered as the most promising energy storage technology for portable and mobile applications. High capacity materials - silicon (Si) and Si-based materials as well as high voltage cathodes have long been considered as materials for the next generation of LIBs. Despite significant efforts the use of these materials is still limited due to poor long-term stability. An alternative pathway to increase the performance of the modern LIBs is the development of thicker electrodes: that will result in increased ratio of active components (anode /cathode) to inactive components (current collector, separator, casings) delivering substantially improved energy density. However, the increase of the electrode’s thickness leads to a number of challenges: longer pathways for the Li ions to reach all active sites, which reduces the rate capacities and increases the overpotentials; longer paths for the electronic transport also leads to increased electrical resistance of the electrodes. Therefore, an increase in energy density comes the cost of lower power densities. In addition, the currently adopted preparation routines for LIB’s electrodes (slurry/tape casting) have substantial limitations: preparation of thicker electrodes typically results in cracking and delamination of active material layer. Therefore, new methods and procedures are required to obtain electrode’s thicknesses above current state-of-art (usually > 100 micrometer).
The aim of this proposal is to develop electrodes for LIBs with optimized ionic and electronic transport properties capable of delivering higher energy densities without compromising power density (i.e. deliver fast charging performance to LIBs with high energy density).
This will both maximize the output of and accelerate research efforts in the field, and thus be invaluable for both the Norwegian and International battery research groups and, by extension, the international community.