Week 1 Understanding Different Battery Chemistry
1.Prepare a table which includes materials and chemical reactions occuring at the anode and cathode of LCO,LMO,NMC,LFP and LTO type of lithium ion cells?
A) Batteries are a collection of one or more cells whose chemical reactions create a flow of electrons in a circuit. All batteries are made up of three basic components: an anode (the '-' side), a cathode (the '+' side), and some kind of electrolyte (a substance that chemically reacts with the anode and cathode).
When the anode and cathode of a battery is connected to a circuit, a chemical reaction takes place between the anode and the electrolyte. This reaction causes electrons to flow through the circuit and back into the cathode where another chemical reaction takes place. When the material in the cathode or anode is consumed or no longer able to be used in the reaction, the battery is unable to produce electricity. At that point, your battery is "dead."
Batteries that must be thrown away after use are known as primary batteries that can be recharged are called secondary batteries.
Without batteries, your quadcopter would have to be tethered to the wall, you would have to hand crank your car, and your Xbox controller would have to plugged in all the time (like in the good old days). Batteries offer a way to store electrical potential energy in a portable container.The invention of the modern battery is often attributed to Alessandro volta It actually started with a surprising accident involving the dissection of a frog.
COMPONENTS OF BATTERY:
Batteries are made up of three basic components: an anode,cathode and an electrolyte, A separator is often used to prevent the anode and cathode from touching, if the electrolyte is not sufficient. In order to store these components, batteries usually have some kind of casing.
Both the anode and cathode are types of electrodes. Electrodes are conductors through which electricity enters or leaves a component in a circuit.
Anode:
Electrons flow out from the anode in a device connected to a circuit. This means that conventional current flows into an anode.In a battery, the chemical reaction between the anode and electrolyte causes a build up of electrons in the anode. These electrons want to move to the cathode, but cannot pass through the electrolyte or separator.
Cathode:
Electrons flow into the cathode in a device connected to a circuit. This means that conventional current flows out from a cathode.In batteries, the chemical reaction in or around the cathode uses the electrons produced in the anode. The only way for the electrons to get to the cathode is through a circuit, external to the battery.
Electrolyte:
The electrolyte is the substance, often a liquid or gel, that is capable of transporting ions between the chemical reactions that happen at the anode and cathode. The electrolyte also inhibits the flow of electrons between the anode and cathode so that the electrons more easily flow through the external circuit rather than through the electrolyte.The electrolyte is crucial in the operation of a battery. Because electrons cannot pass through it, they are forced to travel through electrical conductors in the form of a circuit that connect the anode to the cathode:
Separator:
Separators are porous materials that prevent the anode and cathode from touching, which would cause a short circuit in the battery. Separators can be made from a variety of materials, including cotton, nylon, polyester, cardboard, and synthetic polymer films. Separators do not chemically react with either the anode, cathode, or electrolyte.The voltaic pile used cloth or cardboard (separator) soaked in brine (electrolyte) to keep the electrodes apartions in the electrolyte can b positively charged, negatively charged, and can come in a variety of sizes. Special separators can be manufactured that allow some ions pass but not others.
Casing:
Most batteries need a way to contain their chemical components.Casings, otherwise known as "housings or shells," are simplymechanical structures meant to hold the battery's internals.This lead-acid battery has a plastic casing.
Battery casings can be made of almost anything: plastic, steel, soft polymer laminate pouches, and so on. Some batteries use a conducting steel casing that is electrically connected to one of the electrodes. In the case of the common AA alkaline cell, the steel casing is connected to the cathode.
TYPES OF LITHIUM ION :
Lithium Cobalt Oxide (LCO)
• Lithium Manganies Oxide (LMO)
• Lithium Nickel Cobalt Aluminium (NCA)
• Nickel Manganies Cobalt (NMC)
• Lithium Titanite (LTO)
• Lithium Iron Phospate (LFP)
A lithium-ion battery or Li-ion battery is a type of rechargeable battery. Lithium-ion batteries are commonly used for portable electronics and electric vehicles and are growing in popularity for military and aerospace applications.
Similar to the lead- and nickel-based architecture, lithium-ion uses a cathode (positive electrode), an anode (negative electrode) and electrolyte as conductor. The cathode is a metal oxide and the anode consists of porous carbon. During discharge, the ions flow from the anode to the cathode through the electrolyte and separator, charge reverses the direction and the ions flow from the cathode to the anode. Figure 1 illustrates the process.
Lithium Cobalt Oxide (LiCoO2) - LCO :
Its high specific energy makes Li-cobalt the popular choice for mobile phones, laptops and digital cameras. The battery consists of a cobalt oxide cathode and a graphite carbon anode. The cathode has a layered structure and during discharge, lithium ions move from the anode to the cathode. The flow reverses on charge. The drawback of Li cobalt is a relatively short life span, low thermal stability and limited load capabilities (specific power).
LCO (Lithium cobalt oxide) was invented in the year 1991. Its anode material is LiaC6, the cathode material is LibCo02 and the carrier is Li+.It is used in various applications ranging from electronic devices to all laptops and phone batteries. The majority of lithium-ion batteries for portable devices are cobalt-based. The system contains a cobalt oxide cathode (positive electrode) and graphite carbon anode (negative electrode).
Lithium-ion manganese oxide (LMO) battery :
A lithium-ion manganese oxide battery (LMO) is a lithium ion cell that uses manganese dioxide, MnO2, as the cathode material. They function through the same intercalation/de-intercalation mechanism as other commercialized secondary battery technologies, such as LiCoO2. Cathodes based on manganese-oxide components are earth-abundant, inexpensive, non-toxic, and provide better thermal stability.The architecture forms a three dimensional spinel structure that improves ion flow on the electrode, which results in lower internal resistance and improved current handling. A further advantage of spinel is high thermal stability and enhanced safety, but the cycle and calendar life are limited.
Lithium nickel cobalt aluminium oxides (NCA) battery :
Lithium nickel cobalt aluminum oxide battery, or NCA, has been around since 1999 for special applications. It shares similarities with NMC by offering high specific energy, reasonably good specific power and a long life span. It shares similarities with NMC by offering high specific energy, reasonably good specific power and a long life span. Less flattering are safety and cost. NCA is a further development of lithium nickel oxide; adding aluminum gives the chemistry greater stability.
Lithium Nickel Manganese Cobalt Oxide (NMC) battery :
In short, NMC batteries offer a combination of Nickel, Manganese and Cobalt. They are sometimes known as Lithium Manganese Cobalt Oxide batteries. NMC batteries have a high specific energy or power. NMC in an 18650 cell for moderate load condition has a capacity of about 2,800mAh and can deliver 4A to 5A; NMC in the same cell optimized for specific power has a capacity of only about 2,000mAh but delivers a continuous discharge current of 20A.
Lithium iron phosphate battery (LFP) batteries :
LFP batteries stands for Lithium iron phosphate (LiFePO4) batteries, which is known as li-phosphate batteries as well. They use phosphate as cathode material. In addition, they benefit from the low resistance properties that enhance their thermal stability and safety.This is made possible with nano-scale phosphate cathode material. The key benefits are high current rating and long cycle life, besides good thermal stability, enhanced safety and tolerance if abused.Li-phosphate is more tolerant to full charge conditions and is less stressed than other lithium-ion systems if kept at high voltage for a prolonged time. As a trade-off, its lower nominal voltage of 3.2V/cell reduces the specific energy below that of cobalt-blended lithium-ion.
Lithium-titanate-oxide (LTO) battery :
The lithium-titanate-oxide (LTO) battery is a type of rechargeable battery which has the advantage of being faster to charge than other lithium-ion batteries, but the disadvantage of having a much lower energy density.Li-titanate replaces the graphite in the anode of a typical lithium-ion battery and the material forms into a spinel structure. The cathode can be lithium manganese oxide or NMC. Li-titanate has a nominal cell voltage of 2.40V, can be fast charged and delivers a high discharge current of 10C, or 10 times the rated capacity. The cycle count is said to be higher than that of a regular Li ion. Li-titanate is safe, has excellent low-temperature discharge characteristics and obtains a capacity of 80 percent at-30°C.
2.Compare the differences between each type of Li+ion batteries based on their characteristics
A)
characteristics :
Older batteries were mostly based on rechargeable lead-acid or non-rechargeable alkaline chemistries, with nominal voltages in increments of 2.10 - 2.13 and 1.5 Volts respectively, each representing one individual electrochemical cell.
New special battery chemistries have strained older naming conventions. Rechargeable NiCd (Nickel Cadmium) and NiMH (Nickel Metal Hydride) typically output 1.25 V per cell. Some devices may not operate properly with these cells, given the 16% reduction in voltage, but most modern ones handle them well. Conversely, lithium-ion rechargeable batteries output 3.7 V per cell, 23% higher than a pair of alkaline cells (3 V), which they are often designed to replace. Non-rechargeable lithium-chemistry batteries, which provide exceptionally high energy density, produce about 1.5 V per cell and are thus similar to alkaline batteries.
Many new battery sizes refer to both the batteries' size and chemistry, while older names do not. This summary is only for types relating to battery "sizes".
