A lithium-ion battery or Li-ion battery is a type of rechargeable battery that uses the reversible intercalation of Li ions into electronically conducting solids to store energy. Compared to other types of rechargeable batteries, they generally have higher specific energy, energy density, and energy efficiency and a longer cycle life and calendar life. In the three decades after Li-ion batteries. Specific energy1–270 W⋅h/kg (3.6–972.0 kJ/kg)Energy density250–693 W⋅h/L (900–2,490 J/cm³)Specific power1–10,000 W/kgCharge/discharge efficiency80–90%Watch full videoHistoryOne of the earliest examples of research into lithium-ion batteries is a CuF 2/Li battery developed by in 1965. The breakthrough that produced the earliest form of the modern Li-ion battery was made by British c. . Generally, the negative electrode of a conventional lithium-ion cell is made from . The positive electrode is typically a metal or phosphate. The is a in an . The negative el. . Lithium-ion batteries may have multiple levels of structure. Small batteries consist of a single battery cell. Larger batteries connect cells into a module and connect modules and parallel into a pack. Multi. . Lithium-ion batteries are used in a multitude of applications, including, toys, power tools, and electric vehicles. More niche uses include backup power in telecommu.