Lithium-ion batteries have gradually established themselves in a large number of industries, from microelectronics to portable electronics, including transportation (electric vehicles, soft mobility, rail and air transport) and storage of alternative energy conversions such as solar photovoltaics or wind. strength.
These batteries are considered today as one of the most efficient ways to store electrical energy. In the coming years, the lithium-ion battery market will be mainly driven by transportation (electric vehicles) and, to a lesser extent, alternative energy sources. The outlook for industrial production is to increase this capacity by a factor of 10 by 2030 after a 6-fold increase between 2010 and 2018.
This technology currently represents the best compromise (compared to alternative storage options) between mass and volumetric energy density (the amount of energy that can be stored or transported for a given volume or mass), low self-discharge, long life, low maintenance costs. maintenance and use. over a wide temperature range. Their cost and their specific carbon footprint have dropped significantly in recent years, lithium-ion batteries are a key element in the decarbonization of transport: in France, electricity production is mainly based on nuclear power plants, the carbon footprint (production / use / end of life) of a middle-class car is divided by three compared to its gasoline equivalent.
With so many elements that make up lithium-ion batteries, it seems to be a relevant technological solution for the transition to ecology.
Cobalt and Lithium, two main ingredients but not very affordable compared to demand
However, this technology consumes a lot of metals with a high “criticality”: by 2025, this technology should mobilize most of the world’s production of cobalt (which is used in the composition of positive electrodes, for 65% of production). world) and lithium (for positive and negative electrodes and electrolyte, for 75% of world production), not to mention other metals (nickel, copper, etc.) or carbon graphite that make up battery cells.
Read more: These metals that are running out are a challenge for the society of tomorrow
For example, global lithium consumption increased by 283% between 2010 and 2021, with the price per ton rising from $4,450 in 2012 to $78,000 in 2022. Such a strong increase in demand for raw materials could lead to market tensions as well as major geopolitical risks and exacerbate the environmental impact of mining, which typically uses fossil fuels and chemicals to separate metals from ore.
These contradictions emphasize the importance of solving, along with technical solutions, social issues regarding the relationship of man to the vehicle. For example, limiting the race for autonomy will reduce the size of the batteries and therefore the consumption of raw materials.
Parallel to more virtuous practices, two lines of research seem necessary in the short term: the development of battery recycling and the development of “post-lithium-ion”.
See also: Can electric car batteries be recycled?
“Post-lithium” batteries to avoid lithium supply voltage
By “post-lithium-ion,” we mean new battery technologies based on decades of experience in developing lithium-ion, or even completely disruptive technologies for which everything has to be rethought. Currently, the world’s academic research in the development of these systems is in full swing.
Thus, new ways are being explored to replace the lithium element with other much more common elements on earth, such as sodium, calcium, magnesium and potassium, which can, like lithium, act as a negative electrode in a battery. These lines of research make it possible to foresee possible future tensions in the supply of lithium due to the very uneven distribution of this resource on Earth.
For example, sodium, which is very common and close to lithium in its chemical and electrochemical properties, does not have the same characteristics in terms of mass and volume energy density. On the other hand, it has been shown that sodium-ion batteries can have higher energy performance than lithium-ion batteries, which is of particular interest for some applications.
Batteries based on calcium, magnesium, or potassium currently face significant scientific hurdles (availability and cost of positive electrode materials, interface reactivity) that require longer-term commercialization.
Replace flammable liquid components of lithium-ion batteries
Also, “post-lithium-ion” does not necessarily mean “the end of lithium”, as among the new paths that are benefiting from the most significant industrial investments today are the so-called “all-solid” batteries, the purpose of which is not to replace lithium itself, but flammable liquid components of lithium-ion batteries (known as electrolytes) non-flammable solid components in order to improve user safety.
This route also offers the promise of improved performance in terms of energy density (i.e. lighter batteries and increased range) by using lithium metal (as opposed to lithium ions in lithium-ion batteries) as the negative electrode. This type of battery is especially popular with car manufacturers today, for whom safety and energy density are key elements.
This “all-hard” technology also faces significant technological hurdles, but it is certain that, given the financial and human effort involved, significant progress should be expected in the coming years.
Technology diversification in response to needs
We are seeing technology diversification in response to specific needs depending on the nature of the application.
As long as lithium prices remain acceptable to the globalized world economic system, lithium-ion technology has a bright future ahead of it, particularly in the field of portable electronics.
For an electric vehicle, it is more likely to be a “totally solid” lithium technology if all scientific and logistical obstacles can be removed. Alternatives to lithium are still not very effective, but may be acceptable if the price of lithium rises sharply due to geopolitical tensions. Electric batteries are not the only technological solution. Energy storage using green hydrogen, for example, is a complementary solution.