Lithium-ion battery (LiB) performance is dependent on: how fast lithium ions can move between the electrodes through the electrolyte; and the chemical stability of the electrodes to store the lithium ions. If the properties of the electrolyte are suboptimal, then the batteries cannot store energy effectively, have a limited lifetime, and take a long time to charge. For an electric vehicle, this means reduced range, regular battery replacement and long wait times for users upon “refuelling”. Thus, the electrolyte and its interaction with the electrodes are critical to LiB deployment. Current LiBs are nearing their theoretical performance limits. Moreover, they employ expensive raw materials, such as cobalt, that compromise their green profile and limit the cost reduction needed for their widespread uptake.
In the BetterLiBs project, the project partners will use novel polymerizable zwitterion monomers (ZIMONS) to improve LiB performance. ZIMONS have equal numbers of positive- and negatively-charged functional groups, have high thermal stability and are polymerizable to protect the electrode surfaces. With these properties, we expect they will reduce the cost of LiBs by up to 33%, increase maximum number of cycles to 2,500, increase energy density up to 700 Wh/kg and decrease charging time to 30mins for EV-type 80 Wh battery.
We expect that these battery improvements will increase the viability of transport electrification and provide the necessary energy storage to drive the green transition. Further environmental impact is expected as ZIMONS reduce reliance on hazardous electrolyte additives and promotes the shift to LNMO (LiNi0.5Mn1.51.5O4) cathodes that use less cobalt and nickel, which are toxic as well as energy intensive to mine.
The lead partner, Biomodics, will continue ZIMONS development post-project ready for commercial launch in 2025.