Week 1 Understanding Different Battery Chemistry
CASE -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
Li - ion Batteries:-
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 illustrates the process
Types of Li-ion Cells:-
Lithium Cobait Oxide(LiCo02)-LCO
Its high speciftic energy makes Li-cobait the popular choice for mobile phones, laptops ana digital comeras. The battery consists of a cobalt oxide cathode and a graphite corbon anode. The cathode has a layered structure and during discharge lithium ions move from the anode to the cathode. The flow is reverses on charge. The drowback of Li-cobolt is of relatively short life span, low thermal stability and limited lood capabilities (specific power).
Lithium Manganese Oxide (LiMn204) - LMO
Li-lon with manganese spinel wos first pubilished in the Materials Research Bulletin in 1983. In 1996, Moli Energy commercialised a Li-ion cell with lithium manganese oxide as cathode material. 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 highi thermal stability and enhanced stability, but the cycle and calender life are limited.
Lithium Nickel Cobalt Aluminum Oxide (LiNiCoAIO2) - NCA
LIthium nickel cobolt aluminum oxide battery, or NCA has been around since 1999 lor special applications.Its shares similarities with NMC by offering high specific energy. resonably good specific power and a long life span. Less flattering are saf ety and cost. NCA is a further development of lithium nickel oxide, adding aluminum gives the chemistry greater stability.
Lithium Nickel Manganese Cobalt Oxide (LiNiMnCo02)-NMC
One of the most successtul Li-ion systems is a cothode combination of nicke-manganese cobalt (NMC).Similar to Li- manganese these systerm can be talored to serve as , Energy Cells or Power Cells, For example NMC is an 18650 cell för moderate load condition has a capacity of about 2800 mah and can deliver 4 A to 5 A; NMC in the same cell optimized for specific power has a capacity of only about 2000 mah but deliver a continuous discharge curent of 20A.
Lithiurm Iron Phosphate(LifeP04)-LFP
Li-phosphote offers good eiectrochemical performance with low resistance. This is made possibie with nono scale phosptate cathode material. The key benefits are high current rating and long cycle life besides good thermal stability, enhance safety ond tolerance if obused. Li-phosphote is is more tolerant to full charge conditions and is less stressed than other lithium ion systems if kept ot high voltoge for a prolonged time As a trade off, its lower.nominal voltage of 3.2 V / cell reduces the specific energy below that of cobalt blended lithium ion .
Lithium Titonate (Li2TIO3) - LTO
Bateries with Lihium titanate anodes have been known since the 1980s, Li-titanote replaces the graphite in the anode of a typical Lithium ion battery and the material forms into a spinel structure.The cathode can be lithum manganese oxide or NMC. Li-titanate has a nominal cell voitage of 2.40 V. Can be fast charged ond delivers a high discharge current of 10C or 10 times the rated copacity. The cycle count is scale is said to be highest than that of a regular Li-ion. Li-titanate is safe has excellent low temperoture discharge characterstics and obtains a copacity of 80 percent at-30 C.
The materials & chemical reactions occurring at the anode, cathode and overall reactions of all the types of Li-ion cells are given in the table below;
CASE-2
Lithium ion battery chemistry comparison chart