Tesla’s R&D center has partnered with Dalhousie University (Canada) to develop brand new battery technology. Current electric car batteries keep most of their capacity between 10 and 20 years (on cars that drive about 20,000 km per year).
This is more than enough for a new car – but of course this makes used electric cars much less attractive after a while: the battery is one of the most expensive parts of electric cars. Technologies already exist to push the life of car batteries well beyond this limit.
Tesla could end the battery life problem for good
But current technologies lead to less energy density. This weighs down the batteries at equal capacity and reduces autonomy. The scientific paper baptized, in English “Li[Ni0.5Mn0.3Co0.2]O2 as a Superior Alternative to LiFePO4 for Long-Lived Low Voltage Li-Ion Cells” explains how a slight chemical change can lead to more storage density and increased shelf life.
The technology involves a new chemical composition of electrodes based on Lithium, Nickel, Manganese and Cobalt, and the use of graphite – a technology dubbed NMC532 or NMC. The preliminary tests under laboratory conditions are already impressive. The researchers even had the surprise, by extrapolating the data, to determine a theoretical battery life of a hundred years, provided that the temperature of the accumulator is maintained at around 25°C at all times.
This is quite possible, especially in temperate climates, thanks to active and/or passive temperature regulation systems. The researchers explain:
“Ultra-high precision coulometry and electrochemical impedance spectroscopy are used to complement cycling results and investigate the reasons for improved NMC cell performance. NMC cells, especially those balanced and charged at 3.8 V, exhibit better coulombic efficiency, less capacitance loss, and higher energy density compared to LFP cells and are expected to yield lifetimes close to a century at 25°C.”
For the time being, however, these batteries remain to be built – and it is necessary, one imagines, to still evaluate the impact of the increased use of Cobalt, Nickel and Manganese in these accumulators on the environment and the production costs in the framework of mass production.