Lithium-ion battery

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 were first sold in 1991, their volumetric energy density increased threefold while their cost dropped tenfold. In late 2024, global demand passed per year, while production capacity was more than twice that.
The invention and commercialization of Li-ion batteries has had a large impact on technology, as recognized by the 2019 Nobel Prize in Chemistry.
Li-ion batteries have enabled portable consumer electronics, laptop computers, cellular phones, and electric cars. They are used for grid-scale energy storage and in military and aerospace applications.
M. Stanley Whittingham conceived intercalation electrodes in the 1970s and created the first rechargeable lithium-ion battery, based on a titanium disulfide cathode and a lithium-aluminium anode, although it suffered from safety problems and was never commercialized. John Goodenough expanded on this work in 1980 by using lithium cobalt oxide as a cathode. The first prototype of the modern Li-ion battery, which uses a carbonaceous anode rather than lithium metal, was developed by Akira Yoshino in 1985 and commercialized by a Sony and Asahi Kasei team led by Yoshio Nishi in 1991. Whittingham, Goodenough, and Yoshino were awarded the 2019 Nobel Prize in Chemistry for their contributions to the development of lithium-ion batteries.
Lithium-ion batteries can be a fire or explosion hazard as they contain flammable electrolytes. Progress has been made in the development and manufacturing of safer lithium-ion batteries. Lithium-ion solid-state batteries are being developed to eliminate the flammable electrolyte. Recycled batteries can create toxic waste, including from toxic metals, and are a fire risk. Lithium and other minerals can have significant issues in mining, with lithium being water intensive in often arid regions and other minerals used in some Li-ion chemistries potentially being conflict minerals such as cobalt. Environmental issues have encouraged some researchers to improve mineral efficiency and find alternatives such as lithium iron phosphate lithium-ion chemistries or non-lithium-based battery chemistries such as sodium-ion and iron-air batteries.
"Li-ion battery” encompasses battery types of at least 12 chemistries. Lithium-ion cells can be manufactured to optimize energy density or power density. Handheld electronics mostly use lithium polymer batteries, a lithium cobalt oxide cathode material, and a graphite anode, which together offer high energy density. Lithium iron phosphate, lithium manganese oxide, and lithium nickel manganese cobalt oxide may offer longer life and a higher discharge rate. NMC and its derivatives are widely used in the electrification of transport, one of the main technologies for reducing greenhouse gas emissions from vehicles.

History

One of the earliest examples of research into lithium-ion batteries is a /Li battery developed by NASA in 1965. The breakthrough that produced the earliest form of the modern Li-ion battery was made by British chemist M. Stanley Whittingham in 1974, who first used titanium disulfide as a cathode material, which has a layered structure that can take in lithium ions without significant changes to its crystal structure. Exxon tried to commercialize this battery in the late 1970s, but found the synthesis expensive and complex, as is sensitive to moisture and releases toxic hydrogen sulfide gas on contact with water. More prohibitively, the batteries were also prone to spontaneously catch fire due to the presence of metallic lithium in the cells. For this, and other reasons, Exxon discontinued the development of Whittingham's lithium-titanium disulfide battery.
In 1980, working in separate groups Ned A. Godshall et al., and, shortly thereafter, Koichi Mizushima and John B. Goodenough, after testing a range of alternative materials, replaced with lithium cobalt oxide, which has a similar layered structure but offers a higher voltage and is much more stable in air. This material would later be used in the first commercial Li-ion battery, although it did not, on its own, resolve the persistent issue of flammability.
These early attempts to develop rechargeable Li-ion batteries used lithium metal anodes, which were ultimately abandoned due to safety concerns, as lithium metal is unstable and prone to dendrite formation, which can cause short-circuiting. The eventual solution was to use an intercalation anode, similar to that used for the cathode, which prevents the formation of lithium metal during battery charging. The first to demonstrate lithium ion reversible intercalation into graphite anodes was Jürgen Otto Besenhard in 1974. Besenhard used organic solvents such as carbonates, however these solvents decomposed rapidly providing short battery cycle life. Later, in 1980, Rachid Yazami used a solid organic electrolyte, polyethylene oxide, which was more stable.
In 1985, Akira Yoshino at Asahi Kasei Corporation discovered that petroleum coke, a less graphitized form of carbon, can reversibly intercalate Li-ions at a low potential of ~0.5 V relative to Li+ /Li without structural degradation. Its structural stability originates from its amorphous carbon regions, which serve as covalent joints to pin the layers together. Although it has a lower capacity compared to graphite, it became the first commercial intercalation anode for Li-ion batteries owing to its cycling stability. In 1987, Yoshino patented what would become the first commercial lithium-ion battery using this anode. He used Goodenough's previously reported LiCoO₂ as the cathode and a carbonate ester-based electrolyte. The battery was assembled in the discharged state, which made it safer and cheaper to manufacture. In 1991, using Yoshino's design, Sony began producing and selling the world's first rechargeable lithium-ion batteries. The following year, a joint venture between Toshiba and Asahi Kasei Co. also released a lithium-ion battery.
Significant improvements in energy density were achieved in the 1990s by replacing Yoshino's soft carbon anode first with hard carbon and later with graphite. In 1990, Jeff Dahn and two colleagues at Dalhousie University reported reversible intercalation of lithium ions into graphite in the presence of ethylene carbonate solvent. This represented the final innovation of the era that created the basic design of the modern lithium-ion battery.
In 2010, global lithium-ion battery production capacity was 20 gigawatt-hours. By 2016, it was 28 GWh, with 16.4 GWh in China. Global production capacity was 767 GWh in 2020, with China accounting for 75%. Production in 2021 is estimated by various sources to be between 200 and 600 GWh, and predictions for 2023 range from 400 to 1,100 GWh.
In 2012, John B. Goodenough, Rachid Yazami and Akira Yoshino received the 2012 IEEE Medal for Environmental and Safety Technologies for developing the lithium-ion battery; Goodenough, Whittingham, and Yoshino were awarded the 2019 Nobel Prize in Chemistry "for the development of lithium-ion batteries". Jeff Dahn received the ECS Battery Division Technology Award and the Yeager award from the International Battery Materials Association.
In April 2025, CATL unveiled its Shenxing Plus battery, the first lithium iron phosphate battery claiming a range of over 1,000 km on a single charge. The company also stated the battery supports 4C ultra-fast charging, allowing for 600 km of range to be added in 10 minutes, marking a significant advance in making long-range, fast-charging LFP batteries viable for the mass market.

Design

Generally, the negative electrode of a conventional lithium-ion cell is made from graphite. The positive electrode is typically a metal oxide or phosphate. The electrolyte is a lithium salt in an organic solvent. The negative electrode and the positive electrode are prevented from shorting by a separator. The electrodes are connected to the powered circuit through two pieces of metal called current collectors.
The negative and positive electrodes swap their electrochemical roles when the cell is charged. Despite this, in discussions of battery design the negative electrode of a rechargeable cell is often just called "the anode" and the positive electrode "the cathode".
In its fully lithiated state of LiC₆, graphite correlates to a theoretical capacity of 1339 coulombs per gram. The positive electrode is generally one of three materials: a layered oxide, a polyanion or a spinel. More experimental materials include graphene-containing electrodes, although these remain far from commercially viable due to their high cost.
Lithium reacts vigorously with water to form lithium hydroxide and hydrogen gas. Thus, a non-aqueous electrolyte is typically used, and a sealed container rigidly excludes moisture from the battery pack. The non-aqueous electrolyte is typically a mixture of organic carbonates such as ethylene carbonate and propylene carbonate containing complexes of lithium ions. Ethylene carbonate is essential for making solid electrolyte interphase on the carbon anode, but since it is solid at room temperature, a liquid solvent is added.
The electrolyte salt is almost always lithium hexafluorophosphate, which combines good ionic conductivity with chemical and electrochemical stability. The hexafluorophosphate anion is essential for passivating the aluminium current collector used for the positive electrode. A titanium tab is ultrasonically welded to the aluminium current collector.
Other salts like lithium perchlorate, lithium tetrafluoroborate, and lithium bisimide are frequently used in research in tab-less coin cells, but are not usable in larger format cells, often because they are not compatible with the aluminium current collector. Copper is used as the current collector at the negative electrode.
Current collector design and surface treatments may take various forms: foil, mesh, foam, etched, and coated to improve electrical characteristics.
Depending on materials choices, the voltage, energy density, life, and safety of a lithium-ion cell can change dramatically. Current effort has been exploring the use of novel architectures using nanotechnology to improve performance. Areas of interest include nano-scale electrode materials and alternative electrode structures.