A lithium-ion (or Li-Ion) battery is a rechargeable battery whose operation is based on the exchange of lithium ions between two electrodes. We also talk about the lithium-ion accumulator (or Li-Ion battery) when the battery is composed of several cells.
Offering many advantages, Li-Ion batteries are now part of our daily lives. Indeed, they are used as a source of energy on many electronic devices or mobile electrical appliances (smartphones, laptops, vacuum cleaners...). They are also used in hybrid and electric vehicles.
Lithium-ion batteries are rechargeable batteries:
Like all batteries, they exploit the electro-chemical principle of ion circulation between two electrodes: one positive (the cathode), and the other negative (the anode).
The exchange of positively charged atoms (ions) takes place through a conducting liquid called an electrolyte. By circulating between the two electrodes, the ions make it possible to discharge the battery by supplying electricity, or to recharge it, according to the reverse process.
Depending on their technology, batteries use different materials. Unlike a lead-acid battery used to start internal combustion engines (diesel, gasoline...), a lithium-ion battery uses lithium ions (Li+) to produce energy. Thus, we find today a wide variety of batteries with their own characteristics and adapted to different uses: lead batteries, lithium-ion (Li-Ion), and nickel-cadmium (Ni-Cd)...
In a Li-On battery, the positive electrode is often made of a metal oxide which can be cobalt-lithium dioxide for lithium-cobalt oxide batteries or manganese dioxide. The negative electrode is usually made of graphite.
In the discharge phase, lithium ions (Li+) detach from the graphite electrode and move through the electrolyte to the positive electrode. In the charging phase, it is the opposite: Li+ ions are released from the positive electrode to the graphite electrode.
There are multiple advantages of lithium-ion (Li-Ion) batteries which make this technology one of the most attractive to date:
This is why Li-Ion batteries are widely present today in all our daily equipment (smartphones, laptops, household appliances...).
The big weakness of Li-Ion batteries is their danger. In effect, they can explode suddenly if overloaded, causing property damage or even fire.
To secure their use, an electronic management is necessary to control their operation and to cut the circuits in case of anomaly (overload, over-voltage, temperature increase...). The management of the Li-Ion batteries is carried out by means of electronic components called the Battery Management System (or BMS).
Li-Ion batteries are also sensitive to shock and punctures which make them inflammable. This powerful technology can therefore be dangerous if misused: this restricts their use and requires special precautions for their storage and transport.
The production of Lithium-Ion batteries represents a major challenge for the manufacture of electric vehicles, which is currently booming. In this field, Asian countries dominate the market with:
In the United States, Tesla Group's Gigafactory 1 produces nearly 35 GWh/year. The company plans to build several more gigafactories to accelerate battery production in the coming years.
For the supply of the European and French market, the tendency is to establish Asian manufacturers in Europe. We also note the emergence of several Gigafactories on the European territory such as:
In a 2020 battery pack price report, the Bloomberg NEF strategy research institute says that production costs have fallen in ten years (from 2010 to 2020) from over $1,000/kWh to just over $100/kWh. The adoption of lithium metal batteries could reduce current costs by 40% over the next 10 years.
Lithium ion cells and batteries are considered dangerous goods and are subject to strict storage and transportation regulations worldwide.
Different measures are then applied according to the modes of transport used: road, rail, river, sea or air.
In particular, it is appropriate to:
Transportation regulations vary depending on the capacity and nature of the lithium batteries being carried.
Lithium batteries are tested for classification purposes prior to their first shipment. When they are picked up and shipped, they must then be packaged and the packages labelled accordingly.