what is Lithium Ion Battery – an overview. A lithium-ion battery, also known as a Li-ion battery, is a type of rechargeable battery made up of cells in which lithium ions move from the negative electrode to the positive electrode via an electrolyte during discharge and back again during charging- simply termed as What is a lithium-ion battery?
Li-ion cells use an intercalated lithium compound as the positive electrode material and typically graphite as the negative electrode material. Li-ion batteries have a high energy density, no memory effect (with the exception of LFP cells), and a low self-discharge rate.
Cells can be designed to prioritize energy or power density. However, because they contain flammable electrolytes, they can cause explosions and fires if damaged or incorrectly charged. in this blog, we will discuss What is a lithium-ion battery? and How was it Created?
What is a lithium-ion battery an Overview? and How was it Created
History
- In the 1970s, M. Stanley Whittingham discovered the concept of intercalation electrodes and invented the first rechargeable lithium-ion battery, based on a titanium disulfide cathode and a lithium-aluminum anode, which was patented in 1977 and assigned to Exxon.
- In 1980, John Goodenough expanded on this work by employing lithium cobalt oxide as a cathode. Akira Yoshino developed a prototype Li-ion battery in 1985, based on earlier research by John Goodenough, M.
- Stanley Whittingham, Rachid Yazami, and Koichi Mizushima in the 1970s and 1980s, and a commercial Li-ion battery was developed in 1991 by a Sony and Asahi Kasei team led by Yoshio Nishi.
- Lithium-ion batteries are widely used in portable electronics and electric vehicles, and their use in military and aerospace applications is growing.
Anode
Lithium metal is the lightest metal with the highest specific capacity (3.86 Ah g1) and the lowest electrode potential (3.04 V vs. standard hydrogen electrode), making it an ideal anode material for high-voltage and high-energy batteries. Nonetheless, the electrochemical.
The potential of Li+/Li is higher than the lowest unoccupied molecular orbital (LUMO) of practically all molecules.
Unless a passivating agent is used, known non-aqueous electrolytes will undergo continuous electrolyte reduction.
The solid electrolyte interface (SEI) is created.
1. Due to the large volume change and high reactivity, the SEI is susceptible to damage and repairs non uniformly on the surface of lithium metal of lithium metal, causing dendrite growth and the cell to short-circuit and catch fire.
To avoid lithium metal safety concerns, Armand proposed building Li-ion batteries with two different intercalation hosts.
Besenhard reported the first graphite electrode based on Li-ion intercalation, demonstrating that graphite can intercalate several alkali-metal ions, including lithium.
Li-ions
Intercalates of graphite Li-ions with layered structures and half-filled pz orbitals perpendicular to the planes and capable of interfering with the Li 2s orbitals to limit volume expansionas well as dendrite development
However, graphite’s specific capacity (LiC6, 0.372 Ah 1 is much higher. smaller than the density of lithium metal.
Intercalation materials such as graphite were increasingly viewed as a viable anode in the race to replace lithium metal for better safety until Moli Energy issued a total recall of lithium metal batteries following several fire accidents.
At the time, electrolyte co intercalation (propylene carbonate PC) resulted in graphite exfoliation and collapse posing a Its application in a battery cell poses a challenge.
Cathod
To accommodate the high capacity of lithium metal, conversion-type cathodes containing metal fluorides, sulphides, or oxides were initially considered.
When the battery is running,These materials react to form phases with varying structures and properties new arrangements of ions,
As a result, conversion electrodes do not Allow for multiple cycles of bond breaking and reforming. throughout each cycle.
Scientists are aware of the limitations of conversion reactions turned to new lithium ion storage mechanisms with no moving parts
Cycling causes structural collapse. Chalcogenides of metals (MX2) with a layered structure and room to store Li-ion guests received attention from Whittingham and Exxon7 coworkers who demonstrated that titanium disulfide (TiS2) can be chemically synthesised intercalate Li-ions throughout their entire stoichiometric range with reduced lattice expansion.
The TiS2/Li battery’s low voltage indicates that its energy density is limited. Goodenough turned to the oxide equivalents of metal chalcogenides in search of new cathode materials that intercalate Li-ions at higher potentials.
(MX2, where X equals O) He observed that the peak of the S-3p6 bands is higher in energy than the O-2p6 bands, resulting in Metal oxides have higher intercalation potentials than metals.
Sulphides. The higher energy of metal S-3p6 bands Sulfides are associated with a lower electrostatic Madelung energy.(larger sulphide ion) and a higher energy required to transfer an electronAt infinite separation, an electron is transferred from the cation (Mn+) to S-/S2-.LiCoO2 (lithium cobalt oxide) which can reversibly absorb and release Li-ions at different potentials greater than 4.0 V vs. Li+ /Li and enabled a 4.0 V rechargeable battery when coupled with lithium metal anode.
However, cobalt has limited abundance, forming a cost barrier to its application.
Polyanion oxide
Polyanion oxide offers cost savings due to the abundance of transition metals such as Fe, as well as a bc.
Discoveries that shaped modern lithium-ion batteries. (a) the development of anode materials such as lithium metal and petroleum
(b) electrolytes with the solvent propylene carbonate (PC), a mixture of ethylene carbonate (EC), and at least one linear carbonate,
(c) cathode materials selected from dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), and many additives.
Intercalation materials titanium disulfide (TiS2) and lithium cobalt oxide are examples of conversion-type materials (LiCoO2).
improved thermal stability and safety as a result of the tight covalent bond The bonding of oxygen However, it has a poor electronic system.
Lower densities and higher conductivity. So far, layered oxides with high gravimetric and volumetric energy densities have been the most popular cathodes among the three classes of oxides10, and the The LiCoO2 electrode is now the most common cathode material most personal electronic devices are powered
Electrolyte.
An electrolyte’s working window is determined because of its LUMO and most occupied molecular orbital (HOMO),which must be greater than the electrochemical potential anode (a) and less than the cathode’s electrochemical potential (c), correspondingly (LUMO > a, HOMO c). In addition, a On the anode, a stable passivating SEI layer should be formed.
In the case of LUMO an or HOMO > c, the cathode is used. The reactants in the electrochemical reactions in a lithium-ion cell are anode and cathode materials, both of which contain lithium atoms.
An anode oxidation half-reaction produces positively charged lithium ions and negatively charged electrons during discharge.
The oxidation half-reaction may also generate uncharged material at the anode. In a reduction half-reaction, lithium ions move through the electrolyte, electrons move through the external circuit, and they recombine at the cathode (along with the cathode material).
The electrolyte and external circuit, while providing conductive media for lithium ions and electrons, do not participate in the electrochemical reaction.
During discharge, electrons flow through the external circuit from the negative electrode (anode) to the positive electrode (cathode).
Discharging transfers energy from the cell to wherever the electric current dissipates its energy, which is mostly in the external circuit, because the reactions during discharge lower the chemical potential of the cell.
These reactions and transports occur in the opposite direction during charging: electrons move from the positive electrode to the negative electrode via the external circuit. The external circuit must provide electric energy to charge the cell. This energy is then stored in the cell as chemical energy.
Both electrodes allow lithium ions to move into and out of their structures via insertion (intercalation) or extraction (deintercalation).
These batteries are also known as “rocking-chair batteries” or “swing batteries” because the lithium ions “rock” back and forth between the two electrodes.
Charging n discharging
During discharge, lithium ions (Li+) transport current from the negative to positive electrodes of the battery cell via the non-aqueous electrolyte and separator diaphragm.
During charging, an external electrical power source (the charging circuit) applies an over-voltage (a higher voltage than the battery produces of the same polarity), causing a charging current to flow within each cell from the positive to the negative electrode, i.e. in the opposite direction of a discharge current under normal conditions.
In a process known as intercalation, the lithium ions migrate from the positive to the negative electrode and become embedded in the porous electrode material.
Charging procedures for single Li-ion cells and complete Li-ion batteries differ slightly:
A single lithium-ion battery is charged in two stages:
- Continuous current (CC).
- Constant Voltage (CV).
A Li-ion battery (a series of Li-ion cells) charges in three stages:
- Continuous current.
- Balance (not required once a battery is balanced).
- Voltage is constant.
Rechargeable Li-ion battery
Rechargeable Li-ion battery research dates back to the 1960s, with one of the earliest examples being a CuF 2/Li battery developed by NASA in 1965. M.
Stanley Whittingham, a British chemist, made the breakthrough that resulted in the first form of the modern Li-ion battery in 1974, when he first used titanium disulfide (TiS2) as a cathode material, which has a layered structure that can take in lithium ions without significant changes to its crystal structure.
Exxon attempted to commercialise this battery in the late 1970s, but the synthesis was too expensive and complicated because TiS 2 is sensitive to moisture and emits toxic H 2S gas when it comes into contact with water.
Furthermore, due to the presence of metallic particles, the batteries were prone to spontaneously catching fire.
Early attempts to develop rechargeable Li-ion batteries used lithium metal anodes, which were eventually abandoned due to safety concerns, because 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 the cathode, which prevents lithium metal formation during battery charging.
A variety of anode materials were investigated; in 1987, Akira Yoshino patented the first commercial lithium-ion battery, which used an anode of “soft carbon” (a charcoal-like material) in conjunction with Goodenough’s previously reported LCO cathode and a carbonate ester-based electrolyte.
Sony began producing and selling the world’s first rechargeable lithium-ion batteries in 1991, based on Yoshino’s design.
In 2012, John B. Goodenough, Rachid Yazami, and Akira Yoshino were awarded the IEEE Medal for Environmental and Safety Technologies for developing the lithium-ion battery; in 2019, Goodenough, Whittingham, and Yoshino were awarded the Nobel Prize in Chemistry “for the development of lithium-ion batteries.”
In 2010, global lithium-ion battery production capacity was 20 gigatonne-hours (GWh). By 2016, it had increased to 28 GWh, with China accounting for 16.4 GWh.
In 2020, global production capacity was 767 GWh, with China accounting for 75%. Production in 2021 is expected to be between 200 and 600 GWh, with predictions for 2023 ranging from 400 to 1,100 GWh.
Full-cell Li-ion batteries
- Asahi Kasei Corporation created a fully rechargeable battery by combining the petroleum coke anode with Goodenough’s LiCoO2 cathode, which Sony commercialized in 1990.
- The discovery of Sanyo’sResearchers and Dahn’s work with EC as a co-solvent paved the way the path to the development of graphite-based Li-ion batteries increased the voltage and energy density of the anode to 4.2 V and 400 Wh L-1 is the equivalent. Guyomard and Tarascon18 published their findings in 1993.
- LiPF6 in EC/DMC was reported as a new electrolyte formulation for its enhanced oxidation stability.
- This electrolyte is still present until today, one of the most popular electrolytes, providing LiCoO2-based Li-ion batteries have a threefold increase in energy density (250 Wh). kg-1, 600 Wh L-1) than first-generation devices.
Uses of Li ion Batteries
Consumer electronics and electric vehicles use the vast majority of commercial Li-ion batteries. Among these devices are:
Mobile phones and smartphones, laptops and tablets, digital cameras and camcorders, electronic cigarettes, handheld game consoles, and torches are examples of portable devices (flashlights).
Power tools: Li-ion batteries are used in cordless drills, sanders, saws, and a variety of garden tools such as whippers and hedge trimmers.
Electric vehicles include electric cars, hybrid vehicles, electric motorcycles and scooters, electric bicycles, personal transporters, and advanced electric wheelchairs. Radio-controlled models, model aircraft, aircraft, and the Mars Curiosity rover are also on display.
Backup power in telecommunications applications is one of the more specialised applications. Although they are expensive, lithium-ion batteries are frequently mentioned as a potential option for grid energy storage.
RECYCLING
- Li-ion batteries are classified as non-hazardous waste because they contain fewer toxic metals than other types of batteries that may contain lead or cadmium.
- Elements from lithium-ion batteries, such as iron, copper, nickel, and cobalt, are considered safe for incinerators and landfills.
- These metals can be recycled, usually by burning away the other materials but mining is still cheaper than recycling.
- The accumulation of battery waste poses technical challenges as well as health risks. Because the production of lithium-ion batteries has a significant impact on the environmental impact of electric vehicles, the development of efficient waste repurposing methods is critical.
FIRE/ Saftey HAZARD
Because they contain a flammable electrolyte and may become pressurised if damaged, lithium-ion batteries can pose a safety risk. An overcharged battery cell could cause a short circuit, resulting in explosions and fires.
A Li-ion battery fire can be started by
(1) thermal abuse, such as poor cooling or an external fire,
(2) electrical abuse, such as overcharging or an external short circuit,
(3) mechanical abuse, such as penetration or a crash, or (4) internal short circuit, such as due to manufacturing flaws or ageing.
Because of these risks, testing standards are more stringent than for acid-electrolyte batteries, requiring a broader range of test conditions as well as additional battery-specific tests, and safety regulators impose shipping restrictions.
Conclusion
These developments encourage us to be open-minded and daring in our pursuit of disruptive innovation in battery designs.
The influence of lithium-ion batteries is set to grow portable electronics to domains critical to the long-term viability of the social structure To meet the ever-increasing demand for electrified vehicles, continued transportation and large-scale energy storage solutions
The key lies in material discoveries and game-changing chemistry to realising the full potential of lithium-ion batteries significantly increased cost efficiency, power and energy densities, as well as security
