According to US Department of Energy's (DOE) Vehicle Technologies Office, the volumetric energy density of lithium-ion batteries used in EVs has significantly increased in the last decade.
In 2008, lithium-ion batteries had a volumetric energy density of 55 watt-hours per liter, while in 2020, this had increased to 450 watt-hours per liter. Volumetric energy density refers to the amount of energy that can be contained within a given volume.
Increasing the volumetric energy density of batteries allows electric vehicles to travel further without increasing the size of the battery pack. Conversely, it can allow an EV to travel the same distance with a smaller battery pack, thus saving space, weight, and manufacturing costs.
The substantial increase in energy density points to the fact that robust R&D and heavy investments in battery development by the global battery industry has yielded impressive gains. Given the improvements and breakthroughs in the last two years, the improvement in 2022 is likely to be even higher than 2020.
In general, battery makers focus on two aspects of energy density, namely gravimetric energy density and volumetric energy density, to make EVs lighter, thereby improve weight-to-range efficiency. Gravimetric energy density, also referred to as specific energy, is the available energy per unit mass of a battery unit.
It is worth mentioning that world's largest battery maker CATL recently announced that its latest CTP 3.0 battery units boast a volumetric density of over 290 watt-hours per liter for LFP chemistry and over 450 watt-hours per liter in NCM chemistry batteries.