4. Conclusion

After coexisting in the early 1990s with three battery technologies that accounted for virtually the entire market, Li-ion batteries have gradually established themselves as the rechargeable source of electrical energy in virtually every device requiring an on-board battery. This hegemony is the result of unprecedented performance in terms of energy density, the achievement of a high degree of safety, combined with a production cost adapted to mass markets. The progress made in Li-ion technology, the increase in production capacity and the reduction in costs achieved during the first twenty years of its development have made it possible, since 2010, to integrate this technology into electric vehicles, including buses. The setting up of the first Gigafactories, including Tesla's in Reno in 2014, made it possible to take the plunge and set the wheels in motion for widespread deployment around...