These days, lithium-ion batteries are the talk of the town. Their inventor, Nobel Prize winner in Chemistry, John B. Goodenough, passed away at the ripe old age of 100 on 26 June 2023. 

It was he who made so many inventions possible. Without his work and discoveries, electric cars would not be where they are. They would have modest performance, limited range, and short life span. Not so. If, on the other hand, zero-emission cars are a concrete reality today, much of the credit goes to lithium-ion batteries. Let's try to understand how they are made and how they work. 

How they are made

From the point of view of architecture, lithium ion batteries, or rather the cells that make them up, consist of an anode (negative electrode), a cathode (positive electrode), a separator (a solid material that, as the name suggests, divides anode and cathode) and an electrolyte (usually liquid and which allows the passage of lithium ions between anode and cathode and vice versa).

Lithium-ion batteries work because they alternate between charge cycles (when they receive energy from an external source) and discharge cycles (when they release energy to power any device, such as a household appliance, a mobile phone or the motor of an electric car).

Un pacco batteria Mercedes

A Mercedes battery pack

During charging, the cathode gives up some of its lithium ions to the anode, while during discharging, the reverse process takes place, with the anode giving up lithium ions to the cathode, providing energy.

Lithium-ion batteries: advantages 

Lithium is the third element in the periodic table and the least heavy metal on earth. Due to this mass issue alone, it has a great advantage over the other elements. Lithium-ion batteries also have a higher energy density than other types of batteries, which makes it possible to make batteries that are smaller in size (and weight). In addition, they recharge quite quickly.

Lithium ion batteries: disadvantages

Lithium-ion batteries, however, also have disadvantages. First of all, they have a limited life and tend to lose performance as you use them. It is not for nothing that manufacturers offer a warranty on the batteries they fit in electric cars that is usually around eight years and 160,000 km (99,420 miles)

La Tesla Roadster del 2011 all'asta negli USA

A 2011 Tesla Roadster

Next, lithium-ion batteries are expensive. Compared to nickel-cadmium batteries, which have far less performance, they can cost up to 40 per cent more. Finally, because of the liquid electrolyte, they are flammable and tend to catch fire if they overheat.

Who uses them and when

Lithium-ion batteries, as mentioned, are the standard. They have supplanted lead-acid and nickel-metal hydride batteries, establishing themselves as by far the most popular batteries in electric cars. Among the first to install them was the Tesla Roadster in 2008, which in a way paved the way for the modern electrification of the transport world.

Now, in an ever-changing landscape, they are making way for new technologies, such as LFP or sodium-ion batteries. But they remain the best solution for many zero-emission models that seek performance before economy at all costs, and they will also be used in the future to shape many of the solid-state batteries that will be appearing on the market in the near future.

Gallery: The Volkswagen gigafactory in Salzgitter