In the late1970s, a group of scientists started working on a rechargeable battery, that would later come out to be known as Lithium-ion battery. Today we are very much familiar with lithium-ion batteries. Recently, three scientists namely, John B. Goodenough, M. Stanley Whittingham, and Akira Yoshino got Nobel prize in Chemistry for their work in this battery.
Earlier at the time of the oil crisis in the 1970s, Stanley Whittingham began exploring the idea of a new battery that could recharge in a short time. But the search was halted due to safety concerns related to the battery. Later in the 1980s, John B. Goodenough did some experiments and came out with the lithium-cobalt battery that doubled its energy potential. Five years later, Akira Yoshino of Meijo University in Nagoya, Japan, made another leap in this journey. The battery performance was more stable thus creating the prototype of the lithium-ion battery
Lithium-ion batteries have revolutionized modern day living. As Whittingham said at a recent conference, “Lithium batteries have impacted the lives of almost everyone in the world.” He’s still working on battery research, and we’re excited to see how the Nobel Prize win helps drives the industry forward.
What is a lithium-ion battery?
It is a modern battery that uses lithium-ion as the main component of its electrochemistry. In the discharge cycle, lithium atoms ionise at the anode and separate from their electrons to travel through electrolyte and reach the cathode. Here, they again combine with their electrons and neutralize electrically.. As lithium ions are small in size ( one third to the size of hydrogen and helium ions) they can move through the micro permeable separator between anode and cathode.
Li-ion battery uses different materials for electrodes. One of the most commonly used materials is a combination of Lithium-cobalt oxide at cathode and graphite at the anode. These electrodes are found in electronic devices like laptops and cellphones. Moreover, other materials are used as cathodes like Lithium manganese oxide and lithium iron phosphate, in hybrid electric vehicles.
How does a lithium-ion battery works?
Similar to other batteries, a rechargeable lithium-ion battery is also made of one or more cells that generate the power. Each cell comprises a positive electrode connected to the positive terminal of the battery, a negative electrode connected to the negative terminal of the battery, and an electrolyte which serves as the medium to let the transfer of ion between the electrodes.
Generally, lithium iron phosphate (LiFePo) or lithium-cobalt oxide (LiCoO) makes the positive electrode. The negative electrode has carbon (graphite) and electrolytes have different materials for different batteries.
The working of lithium-ion batteries can be understood like this: when a battery is charging, the positive electrode (lithium-cobalt oxide) gives up some of its lithium ions. These ions move towards the negative electrode through the electrolyte and neutralize there. In this process, the battery is charged.
When the battery is discharging, the same lithium ions on the negative electrode move towards the positive electrode through an electrolyte, thus generating power from the battery. In both cases, the electrons move in the opposite directions in the outer circuit to which ions move.
The movement of electrons in the outer circuit and ions through the electrolyte is an interdependent process, if either stop so does the other. If ions movements are less through the electrolyte because the battery is discharging, the movement of the electrons will also decrease, therefore there is less power.
In the same manner, when the battery is powering, the electrons flow reduces and so does the ions flow. We should be mindful here that a battery discharges at a very slow rate even though it not in use.
Lithium-ion batteries have a built-in electronic controller that controls its charging and discharging. This prevents the battery from overheating and exploding.
Types of Lithium-ion batteries?
There are various types of lithium-ion batteries depending on its compositions.
Lithium cobalt oxide
This type of battery is has lithium carbonate and cobalt. It is also known as lithium cobaltate or lithium-ion cobalt batteries. It has graphite carbon at anode and cobalt oxide at the cathode. While discharging lithium-ion moves from the anode to cathode and reverse in the flow when it is charging. Li-Co oxide battery has a specific energy, thus it work as power source in cell phones, laptops, and electronic cameras.
However, this type of battery has come negative points, including limited specific power and shorter battery life.
Lithium manganese oxide
These batteries are also called lithium manganate or lithium-ion manganese batteries or manganese spinel or li-manganese. In 1996, it was first made in the lithium-ion cell with manganese oxide as cathode material by Moli Energy. These batteries are safer than other types of batteries because they have high-temperature stability.
This makes their application in medical equipment, laptops, electric power trains cars and bikes, and many other devices.
Lithium iron phosphate
These are also called li-phosphate batteries because they use phosphate as a cathode. They offer low resistance which makes them safe and thermally stable. Li-phosphate batteries are highly durable, cost-effective, and long life cycles. The shelf life is highers for them which means a fully charged battery wont lose its power over time when not in use.
For all these reasons, electric power train vehicles and many other devices that need longer lifecycle and safety, uses them.
Lithium nickel manganese cobalt oxide
These are also called NMC batteries or lithium manganese cobalt oxide. They have several materials similar to the lithium-ion battery. In these batteries, nickel, manganese, and cobalt makes the cathode. The usual cathode combination is 60 % nickel, 20 % manganese, and 20% cobalt, which is cost-effective as compared to other batteries owing to expensive cobalt. The cost of these batteries may be reduced in the future as many battery makers are seeking a way to use less cobalt.
NMC can have either high specific power or high specific energy density, but not both.The power trains of the cars and power tools uses this battery due to its low self-heating rate.
Lithium nickel cobalt aluminum oxide
Lithium nickel cobalt aluminum oxide batteries are also known as NCA batteries. These are not so popular in the common industry but in the automotive industry. NCA batteries provide a good lifespan with high energy. Due to this, powertrains of cars and grid storage uses them. However, they are not as safe as other lithium-ion batteries and are quite costly.
It is also known as li-titanate. It has a fast recharging time due to its advanced nanotechnology. Its application has been rising as it is improving in its efficiency. It has low inherent voltage or low energy density than other lithium-ion batteries.
However, its density is higher than other nonlithium ion batteries. Its application is in the field of military, aerospace, and even in storing solar or wind energy and grid energy.
What are the uses of li-ion batteries?
Today wide range of devices and machines uses lithium-ion batteries. Ranging from medical equipment to cars, these batteries provide high performance and safety.
Some of the applications of rechargeable lithium-ion batteries are:
Emergency Power Backup Or UPS (Uninterruptible Power Supply)
Lithium-ion battery acts as a power back in case of a sudden cut in electricity. It protects the devices that damage due to a sudden cut in electricity. Today, almost all the emergency power backups use this battery. However, it different from generators and other emergency power backup as it allows us to shut down the equipment connected to it.
Dependable Electric And Recreational Vehicle Power
Due to the lifespan of over 10 years, lithium-ion batteries give reliable power for the long journey and loses a very small amount of power when not in use. It’s light weightiness as compared to lead-acid batteries, helps to reduce the overall weight of power trains of cars or bikes, thus making them more efficient.
Reliable And Lightweight Marine Performance
These batteries work well even in the machines that work in the water. Whether, its a small boat, yacht, lithium batteries are capable enough to power these machines and give a good performance. Also, their weight which is a fraction of lead-acid battery gives you a long-lasting rechargeable source of power.
Solar Power Storage
Since, the world has started looking towards the more non-fossil fuel energy, the power generation through windmills, solar cells have increased over the years. This brings out the need for a power storage system that stores the power with maximum efficiency, plus there is the least discharge of power when not in use.
Lithium batteries are best for storing the power from such sources as it fastly charges.
Surveillance Or Alarm Systems In Remote Locations
There are places where the hardwired electricity cable cannot be setup. For such places, the surveillance systems cannot work due to limited power. However, with rechargeable lithium-ion batteries this feat can be achieved, as li-ion batteries have a long life, compact size, and low power discharge when the system is not in use. The self-discharging rate of the lithium-ion battery is 10 times lower than the lead-acid batteries, thus making them ideal to use when the power is not continuously required.
Personal Freedom With Mobility Equipment
The advanced technology has made life easier for mobility restricted people. From electric wheelchairs to stairs lifts, many people are now dependent on these machines. Lightweight lithium battery allows the mobility equipment to work efficiently as they offer a longer life span, fast charging, size customization, and low self-discharging rate.
Portable Power Packs That Eliminate Downtime
Our phones and laptops commonly has a lithium-ion batteries. Due to their lightweight, the recent devices feel light to carry. They maintain the temperature and the same power flow. Also, their fast recharging allows us to work for long hours on our gadgets when there is no electricity.
Rechargeable lithium batteries are highly durable and economical under challenging conditions. Lithium-ion batteries are up to the mark when we need a reliable power source.