Week 1 Understanding Different Battery Chemistry
1.Prepare a table which includes materials & chemical reactions occurring at the anode and cathode of LCO, LMO, NCA, NMC, LFP and LTO type of lithium ion cells.Give your detailed explanation on it
ANSWER:
Introduction:
Lithium-ion Cells are a secondary type of battery cell that is they are rechargeable and also they are reusable which makes them ideally suited for automotive applications and certain consumer electronics When two or more cells connected they are referred to as batteries Like other batteries Lithium-ion batteries also rely on the chemical energy stored in the bonds and atoms of elements and compounds and utilize this energy in a chemical reaction occurring inside the cell. The chemical energy from this reaction is converted to electrical energy and it is used. Since the Lithium-ion cells are rechargeable, they can perform the reverse reaction using electricity as well
Construction:
Electrolyte
• The electrolyte is an ionic conductor that provides the medium for internal ionic charge transfer between the
electrodes
• The electrolyte must often comprise a liquid solvent containing dissolved chemicals the solution that provides
the ionic conductivity
• The Lithium-ion cels use non-aqueous electrolytes
Cathode and Anode
■ The Cathode ad Anoide is the two electrodes that are connected by a wire in an external circuit The electrons
arc passing through the external wire and so an electric current is perorated
■ The Anode refers to the Electrode through which the conventional current enters into a polarized electrical
device.
■ The Cathode refers to the electrode through which conventional current leaves an electrical device.
Separator
a. The Separator physically isolates the positive and negative electrodes. The separator is an ionic conductor but
an electronic insulator
b. It prevents the internal short-circuiting between the two electrodes
Current Collectors:
• The current collectors are the electronic conductors with which the electrodes are mixed It does not take part in
chemical reactions of the cell but instead, it either allows simple electronic connection to reduce the electronic
resistance of an electrode.
Advantages of Lithium-Ion Battery:
Following are the benefits or advantages of Lithium-Ion batteries:
—As mentioned it has a high energy density which is two times compare to Ni-Cd.
—The Lithium-Ion battery is rechargeable.
—There is no memory effect. Hence it is not needed to discharge them completely before recharging.
—The battery can handle many charge/discharge cycles.
Disadvantages of Lithium-Ion Battery:
Following are the disadvantages of Lithium-Ion Battery:
--It lasts only two to three years after the manufacturer. --It is sensitive to high temperatures.
--If the battery is completely discharged, it can no longer be recharged again.
--It is relatively expensive. --If the "separator" gets damaged, it can burst into flames.
1. Lithium Cobalt Oxide (LiCoO2) — LCO
It has high specific energy but low specific power which means that charging and discharging with Current Pate (C) above rated values shorten the battery's life. It has a cobalt Oxide Cathode and Graphite anode. The cathode is layered.
During discharge, the Li-ions move from anode to cathode. The flow reverses during charging. The graphite anode limits its cycle life hence it has a short life span. It has low thermal stability. Its main applications are mobile phones, laptops, cameras, etc.
2. Lithium Manganese Oxide (LiMn2O4) LMO
The Manganese Oxide forms a 3D-spinel structure that improves the ion flow on the electrode. This results in lower internal resistance, which enables fast charging and high-current discharging. Adding to these, spinel structure also packs extra thermal stability. Making it safer compared to LCO. The LMO has a lower cycle life.
Most Li-manganese batteries blend with lithium nickel manganese cobalt oxide (NMC) to enhance the precise energy and prolong battery life. These three active metals, as well as silicon enhancement, can enhance specific energy (capacity), specific power (load capability) or longevity.
Li-manganese has high power and less capacity. It is used for power tools, medical devices as well as in electric vehicle powertrain.
3. Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2) NMC:
The cathodic combination of Nickel Manganese Cobalt is successful as it can be tailored to be either Energy cells or
Power Cells. NMC has a good performance and excels in specific energy. This Lithium-ion battery can deliver a
continuous discharge current.
The advantage of Nickel is its high specific energy but it has poor stability. Whereas Manganese achieves low
internal resistance by forming a spinal structure. Unlike Nickel, Manganese offers low specific energy.
Their combination enhances each other's performances. New electrolytes can boost capacity. It has the lowest self-
heating rate and improved cycle life. This is a battery of choice for electric powertrains and industrial applications.
4. Lithium Iron Phosphate (LiFePO4) LFP:
In this type, Li- Phosphate is used as the cathode since it has good electrochemical performance with low
resistance. This is because of the nano-scale phosphate cathode material.
Various advantages of this Lithium-ion battery chemistry include - long lifecycle, good thermal stability, high
current rating, enhanced safety, and tolerance in case of abuse.
Li-Phosphate is often used to replace lead-acid batteries as it has a moderate specific energy and has a very low
tolerance for moisture, which reduces its cycle life drastically.
Other characteristics include a very flat voltage discharge curve but low capacity. LFP is one of the safest Li-ions in
the market.
5. Lithium Nickel Cobalt Aluminum Oxide (LiNiCoAIO2) NCA:
NCA batteries are gaining importance in electric powertrains and grid storage. They are not common in the
consumer industry but are promising for the automotive Sector. Tesla, the US-based EV manufacturer researches
this technology and uses this Lithium-ion battery chemistry.
NCA has the highest Specific Energy, good Specific Power, and a long life span. High cost and marginal safety are
the negatives.
6. Lithium Titanate (Li2TiO3) LTO:
In this technology, 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 can be fast-charged and delivers a high
discharge current 10 times the rated capacity. The cycle count is higher than the regular Li-ion batteries.
Li-titanate excels in safety and has excellent low-temperature discharge characteristics and life span. The
applications this lithium ion battery chemistry power include electric powertrains, UPS and solar-powered street
lighting.
2.Compare the differences between each type of Li+ion batteries based on their characteristics
ANSWER:
detail individual tables:
Conclusion:
We study the different types of Li+ion batteries based on their characteristics and their chemistry.