Battery for 2,000 miles? Technology can allow, but there are many limitations

A battery technology is evolving, gradually eliminating concerns about autonomy. And from China, there are those who are aware of one more possible path to follow in this field.

This is a question of the lithium-air batteries, which according to IT Home may have a energy density five times higher than that of solid state batteries and a theoretical autonomy of up to 2,000 km for electric vehicles. This is, however, the electrochemical potential and does not necessarily reflect the performance of a car battery.

Wu Kai, chief scientist at CATL – one of the leading manufacturers of automotive batteries – pointed out this technology as an area to explore in long-term research during the 2026 Powerhouse Forum Equipment last May.

Without going into complex technical details, one of the great secrets in these batteries is the fact that oxygen for the active material of the positive electrode to come from the external air, not contributing to battery weight. Metal lithium is the negative electrode, prone to the growth of lithium dendrites in repeated loading and unloading cycles – which is one of the challenges to durability and safety.

Also IT Home writes that there are rumors about a laboratory prototype having reached 1,200 Wh/kg – which already surpasses solid state batteries and could allow to travel more than 1,600 km with one charge. But in theory, the energy density often mentioned in this technology is above 3,500 Wh/kg - reaching 2,000 km of autonomy.

But there are those who put the upper theoretical limit on more than 12,000 Wh/kg – in a perfect scenario, but very unlikely to reach.

There are many limitations

Development, however, will take some years and there are important challenges to be addressed. Right away, laboratory tests do not deal with air contamination in the real world with other elements like carbon dioxide. So there would have to be a filtration system to avoid unwanted reactions to good battery health.

And despite the higher energy density, the size of the set may be another obstacle. The technology requires a gas diffusion layer, air flow channels and pumps or fans to get the oxygen to the required location.

Car News China also talks about the need to remove lithium peroxide from the cathode during loading, and the reversal of the discharge reaction that requires additional energy and can generate reactive oxygen species harmful to certain components – impairing durability and conservation.

The efficiency of air-lithium batteries is well below those of lithium ions, while the lifetime described in laboratory conditions is only around 1,000 cycles. That is, as it is today, technology is not ideal for repeated loading and unloading cycles and for prolonged use in time as required in an automobile.

On the other hand, it is necessary to consider the specific energy parameters (energy stored per unit of mass), volumetric energy density and power density (the speed with which energy can be supplied). It is the combination between the three that determines the practical viability of an electric car and therefore not all battery technologies are adequate.