Week 1 Understanding Different Battery Chemistry

1.

Classification of Battery:

Battery (Primarily it is classified into two types)-----(1) Primary cell. ----(i) Dry cells

(ii) Lithium Cells

(2) Secondary cells (classified into 5 types) ---------(i)Lead acid battery

(ii) Nickel Cadmium battery

(iii) Metal air battery

(iv) Nickel Metal Hydride battery

(v) Lithium-ion battery (classified into 5 types) -----------(a) NMC

(b) NCA

(c) LMO

(d) LTO

(e) LiFePO4 or LiPO

So mainly Lithium-ion battery is classified into 5 types and those are:

(a) NMC

(b) NCA

(c) LMO

(d) LTO

(e) LiFePO4 or LiPO

Except for those one more type of Lithium-ion battery is available on market but this is not suitable for Electric Vehicle application. This battery is called Lithium Cobalt Oxide.

Details of Lithium-ion battery:

• What is a Lithium-ion battery: A lithium-ion (Li-ion) battery is an advanced battery technology that uses lithium ions as a key component of its electrochemistry. During a discharge cycle, lithium atoms in the anode are ionized and separated from their electrons. The lithium ions move from the anode and pass through the electrolyte until they reach the cathode, where they recombine with their electrons and electrically neutralize. The lithium ions are small enough to be able to move through a micro-permeable separator between the anode and cathode. In part because of lithium’s small size (third only to hydrogen and helium), Li-ion batteries are capable of having a very high voltage and charge storage per unit mass and unit volume.

• Anode and Cathode :
• The electrode of a battery that releases electrons during discharge is called anode; We can also say the electrode through which the conventional current enters into polarized electrical device.
• The electrode that absorbs the electrons is the cathode. In other words, The electrode through which the conventional current leaves an electrical device.
• During discharging the battery anode is always negative and the cathode positive. This appears to violate the convention as the anode is the terminal into which current flows.
• In Li-ion battery, Cathode: metal oxide(highest capacity but cost and safety concers, used for NCA,NMC,LCO), Spinels(high power density but poor electronic conductivity and structural stability,used for LMO,LTO) and olivers(better safety and long life but low capacity and voltage, used for LPO).
• In Li-ion battery, Anode: Carbon based Graphite and hard carbon(Low cost, stable and high specific capacity but when the polarity of the anode becomes excessively low it can plate out as metalic lithium on surface of the anode which loose the capacity)

• Electrolyte:

• Ion flow is made possible with an activator called the electrolyte. In a flooded battery system, the electrolyte moves freely between the inserted electrodes; in a sealed cell, the electrolyte is normally added to the separator in a moistened form.
• A mixture of organic solvents such as an ethylene carbonate, dimethyl carbonate and propylene carbonate which contains a dissolved lithium salt but below 0 degree centigrade the ionic transport propertysuffer which can drastically lower cell performance and efficiency.

• Separator:

• The separator segregates the anode from the cathode, forming an isolator for electrons but allowing ions to pass through.

LITHIUM-ION	CATHODE (POSITIVE) ON ALUMINUM FOIL	ANODE (NEGATIVE) ON COPPER FOIL	ELECTROLYTE
Material	Metal oxides derived from cobalt, nickel, manganese, iron, aluminum	Carbon based	Lithium salt in an organic solvent
Full charge	Metal oxide with intercalation structure	Lithium ions migrated to anode.
Discharged	Lithium ions move back to the positive electrode	Mainly carbon

• Advantages of Lithium-ion battery:

1. They have one of the highest energy densities of any battery technology today (100-265 Wh/kg or 250-670 Wh/L). In addition, Li-ion battery cells can deliver up to 3.6 Volts, 3 times higher than technologies such as Ni-Cd or Ni-MH. This means that they can deliver large amounts of current for high-power applications.
2. Li-ion batteries are also comparatively low maintenance and do not require scheduled cycling to maintain their battery life.
3. Li-ion batteries also have a low self-discharge rate of around 1.5-2% per month. They do not contain toxic cadmium, which makes them easier to dispose of than Ni-Cd batteries.

• Disadvantages of Lithium-ion battery:

1. Li-ion batteries still have a number of shortcomings, particularly with regards to safety. Li-ion batteries have a tendency to overheat, and can be damaged at high voltages. In some cases this can lead to thermal runaway and combustion. This has caused significant problems, notably the grounding of the Boeing 787 fleet after onboard battery fires were reported. Because of the risks associated with these batteries, a number of shipping companies refuse to perform bulk shipments of batteries by plane. Li-ion batteries require safety mechanisms to limit voltage and internal pressures, which can increase weight and limit performance in some cases.
2. Li-ion batteries are also subject to aging, meaning that they can lose capacity and frequently fail after a number of years.
3. Another factor limiting their widespread adoption is their cost, which is around 40% higher than Ni-Cd.

Table of Cathode and Anode chemistry of different type of Li-ion batteries:

Sl No	Type of battery	Anode material	Anode reaction	Cathode material	Cathode reaction	Electrolyte
1	Lithium Nickel Manganese Cobalt Oxide Battery(NMC)	LiC6	LiC6<-->Li(+) + e(-) + C6	LiNi(0.8)Mn(0.1)Co(0.1)O2	NiMnCoO2 + Li(+) +e(-) <--> LiNIMnCoO2	Ethylene Carbonate and LiPF6 salt
2	Lithium Nickel Cobalt Aluminium Oxide Battery (NCA)	LiC6	LiC6<-->Li(+) + e(-) + C6	LiNiCoAlO2	NiCoAlO2 + Li(+) + e(-) <--> LiNiCoAlO2	Ethylene Carbonate and LiPF6 salt
3	Lithium Manganese Oxide (LMO)	LiC6	LiC6<-->Li(+) + e(-) + C6	LiMn2O4	MnO2 + Li(+) + e(-) <--> LiMn2O4	Ethylene Carbonate and LiPF6 salt
4	Lithium Titanium Oxide (LTO)	Li4Ti3O12(Lithium Titanate*)	Li4Ti3O12Li4Ti3O12<--> Ti5O12 + 4e(-) + 4Li(+)	Li4Ti3O12	4Mn2O4 + 4Li(+) + 4e(-) <--> Li4Ti3O12	Ethylene Carbonate and LiPF6 salt
5	Lithium Iron Phosphate (LPO)	LiC6	LiC6<-->Li(+) + e(-) + C6	LiFePO4	Feo4 + Li(+) + e(-) <-->LiFePO4	Ethylene Carbonate and LiPF6 salt
6	Lithium Cobalt Oxide (LCO)	LiC6	LiC6<--> Li(+) + e(-) + C6	LiCoO2	CoO2+Li(+) + e(-) <--> LiCoO2	Ethylene Carbonate and LiPF6 salt

*Titanate is noting but Titanium Oxide.

2.

• Different types of Lithium-ion battery:

1. Lithium Nickel Manganese Cobalt Oxide Battery(NMC) : Lithium Nickel manganese Cobalt Oxide batteries, often known as NMC batteries, are constructed of a variety of materials that are universal in lithium-ion batteries. A cathode constructed of a mix of nickel, manganese, and cobalt is included.

   NMC batteries, like other lithium-ion battery types, can have a high specific energy density or a high specific power. They can’t have both features, though. This battery is most commonly seen in power tools and automobile powertrains.

   60% nickel, 20% manganese, and 20% cobalt are commonly the cathode combination ratios. This means that the cost of the raw material is lower than for other lithium-ion battery solutions, as cobalt may be fairly costly. Because some battery manufacturers plan to convert their battery chemistry to a larger percentage of nickel to utilize less cobalt, the price of these batteries may drop even more in the future. Because of its low self-heating rate, this battery type is often used in electric vehicles.

2. Lithium Nickel Cobal Aluminium Oxide Battery (NCA) :

   NCA batteries, or lithium nickel cobalt aluminum oxide batteries, are making their way in electric vehicles and grid storage.

   Although NCA batteries are not widely used in consumer electronics, they have great potential in the automobile industry. NCA batteries offer a high-energy choice with a long lifespan, but they are less safe than other lithium-ion battery types and are rather expensive. To ensure driver safety, NCA batteries must be accompanied by monitoring systems.

   Given the widespread use of NCA batteries in electric vehicles, demand for these batteries may increase as the number of electric vehicles grows.

3. Lithium Manganese Oxide (LMO) :

   Lithium manganese oxide batteries are sometimes known as lithium manganate or lithium-ion manganese batteries, or li-manganese or manganese spinel batteries. The technology for this sort of battery was initially discovered in the 1980s, with the first publication in the Materials Research Bulletin in 1983. Moli Energy manufactured the first commercial lithium-ion cells using lithium manganese oxide as the cathode material in 1996.

   High-temperature stability distinguishes lithium manganese oxide batteries from others, which are also safer than other lithium-ion battery types. As a result, they’re frequently found in medical equipment and devices, but they can also be used in power tools, electric motorcycles, and other applications. Lithium manganese oxide batteries can also be used to power laptop computers and electric vehicles.

4. Lithium Titanium Oxide (LTO) :

   Lithium titanate, often known as li-titanate, is a type of battery that has a growing number of uses. Because of its superior nanotechnology, the lithium-titanate battery has an extremely rapid recharge time.

   Li-titanate batteries are being employed by makers of electric vehicles and bicycles, and this type of battery has the potential to be used in electric buses for public transit. However, these batteries have a lower intrinsic voltage or energy density than other lithium-ion battery types, which might cause problems when it comes to efficiently power automobiles. Despite this, lithium titanate batteries have a higher density than non-lithium-ion batteries, which is a benefit.

   These batteries could be used for military and aerospace applications, as well as storing wind and solar energy and constructing smart grids. Furthermore, according to Battery Space, these batteries could be employed in power system system-critical backups.

5. Lithium Iron Phosphate (LPO) :

   Phosphate is used as a cathode in lithium iron phosphate batteries, often known as li-phosphate batteries. They have low resistance qualities, which improve their thermal stability and safety.

   Durability and a long lifecycle are other advantages – fully charged batteries can be kept with no effect on the battery’s overall charge life. When the lengthy battery life of Li-phosphate batteries is considered, they are frequently the most cost-effective option. The lower voltage of the lithium-phosphate battery, on the other hand, means that it has less energy than other lithium batteries.

   As a result, these batteries are frequently used in electric bikes and other applications requiring a long lifecycle and high levels of safety. These batteries are also commonly used in electric vehicles.

6. Lithium Cobalt Oxide (LCO) :

   Lithium cobalt oxide batteries are manufactured from lithium carbonate and cobalt and are also known as lithium cobaltate or lithium-ion cobalt batteries. These batteries are used in cell phones, laptops, and electronic cameras because of their high specific energy. They have a cobalt oxide cathode and a graphite carbon anode, and lithium ions migrate from the anode to the cathode during discharge, with the flow reversing when the battery is charged.

   This battery has a few disadvantages, including short battery life and low specific power. We also want to let you know that these batteries are not as safe as other varieties. Despite this, they are a popular choice for cell phones and other portable electronic devices because of their properties.

This trade-off shows the different parameters and ratings of it. Lithium Nickel Manganese Cobalt Oxide battery is quite good but comapred to the LPO life span is lesser than it. Though cost is quite equal but for better performance LPO is wide usable in automobile industry.

• Application of different types Lithium-ion battery: