Week 1 Understanding Different Battery Chemistry

1. LMO, NCA, NMC, LFP and LTO type of lithium ion cells.Give your detailed explanation on it.

Ans:

The following table includes materials and chemical reactions occurring at the anode and cathode of LCO, LMO, NCA, NMC, LFP and LTO type of lithium ion cells,

Name	Anode	Cathode	Separator	Electrolyte	Anode Reaction	Cathode Reaction
Lithium cobalt oxide	Graphite	Lithium cobalt oxide	polyolefin	Ethylene carbonate	liC6 – C6 + Li - e	CoO2 + Li + e – LicoO2
Lithium manganese Oxide	Graphite	Lithium manganese Oxide	polyolefin	Lithium Halide	liC6 – C6 + Li - e	MnO2 + li +e – liMnO2
Lithium Nickel Cobalt Aluminum Oxide	Graphite	Lithium Nickel Cobalt Aluminum Oxide	polyolefin	Ethylene carbonate	liC6 – C6 + Li - e	NiCoAlO2 + Li + e – LiNiCoAlO2
Lithium Nickel Manganese Cobalt Oxide	Graphite	Lithium Nickel Manganese Cobalt Oxide	polyolefin	Lithium salt	liC6 – C6 + Li - e	NiMnCoO2 + Li + e – LiNiMnCoO2
Lithium iron phosphate	Graphite	Lithium iron phosphate	polyolefin	Ethylene carbonate	liC6 – C6 + Li - e	FePO4 + Li + e – LiFePO4

Li -ion Batteries:

A lithium- ion battery is a type of rechargeable battery. Li-ion batteries are commonly used for portable electronics and electric vehicle and are growing in popularity for military and aerospace applications.

Similar to lead – and nickel-based architecture, li-ion uses a cathode (+ve electrode), an anode (-ve electrode) and electrolyte as a conductor. The cathode is a metal oxide and carbon is consist of porous carbon. During discharge, the ion flow from anode to cathode through the electrolyte and separator, charge reverse the direction and the ion flow from cathode to anode.

Types of li-ion Cells:

Lithium Cobalt Oxide (LiCoO2) – LCO:

Its high specific energy makes li-cobalt the popular choise of mobile phones, laptops and digital

cameras. The battery consists of a cobalt oxide cathode and a graphite carbon anode. The

cathode has layered structure and during discharge, lithium ion moves from anode cathode. The

flow reverses on charge. The drawback of li-cobalt is relatively short life span, low thermal

stability and limited load capabilities (specific power).

Lithium manganese oxide (LiMn2O4) – LMO:

Li-ion with manganese spinel was first published in the Materials Research Bulletin in 1983. In

1996, Moli Energy commercialized a li-ion cell with lithium manganese oxide as a cathode

material. The architecture forms a three-dimensional spinel structure that improve ion flow on

the electrode, which results in lower internal resistance and improved current handling. A further

advantages of spinel is high thermal stability and enhance safety, but the cycle and calendar life

are limited.

Lithium Nickel Cobalt Aluminium Oxide (liNiCoAlO2) – NCA:

Lithium Nickel Cobalt Aluminium Oxide battery has been around in 1999 for special

applications. it shares similarities with NMC by offering high specific energy. Reasonable good

specific power and a long life splan. Less flattering are safety and cost. NCA is further

development of lithium nickel oxide; adding aluminium gives the chemistry greater stability.

Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2) – NMC:

One of the most successful li-ion systems is a cathode combination of NMC. Similar to

li-manganese these systems can be tailored to serve as energy Cell or power Cell. For

example, NMC in an 1850 cell for moderate load condition has a capacity of about

2800mAh and can deliver 4A to 5A; NMC in the same cell optimized for specific power

has a capacity of only about 2000mAh but delivers a continuous discharge current of 20A.

Lithium Iron Phosphate (LiFePO4) – LFP:

li-phosphate offers good electrochemical performance with low resistance. This is made possible with nano scale phosphate material. The key benefits are high current rating and long cycle life, beside good thermal stability, enhanced safety and tolerance if abused. Li-phosphate is more tolerance to full charge condition and is less stressed then other li-ion system if kept at high voltage for a prolonged time. As a trade-off, its lower nominal voltage og 3.2V/cell reduces the specific energy below that of cobalt-blended lithium-ion.

Lithium Titanate (Li2TiO3) – LTO:

Batteries with lithium titanate anodes have been known since the 1980s. li-titanate replaces the graphite in the anode of a typical li-ion battery and the materials forms into spinel structure. The cathode can be lithium manganese oxide or NMC. Li-titanate has a nominal voltage 2.40V, can be fast charged and delivers a high discharged current of 10C or 10 times the rated capacity. The cycle count is said to be higher than that of a regular ion. Lithium-titanate is safe, has excellent low temperature discharge characteristics and obtain a capacity of 80 percent at -30 degree Celsius.

2.Compare the differences between each type of Li+ion batteries based on their characteristics.

Ans:

Lithium Cobalt Oxide: LiCoO₂ cathode (-60% Co), graphite anode

Short form: LCO or Li-cobalt. Since 1991

Voltages:

3.60V nominal; typical operating range 3.0-4.2V/cell

Specific energy (capacity):

150-200Wh/kg. Specialty cells provide up to 240Wh/kg.

Charge (C-rate):

0.7-1C, charges to 4.20V (most cells); 3h charge typical.Charge current above 1C shortens battery life. 1C; 2.50V cut off. Discharge current above IC shortens

battery life.

Discharge (C rate):

1C; 2.50V cut off. Discharge current above 1C shortens battery life.

Cycle life:

500-1000, related to depth of discharge, load, temperature

Thermal runaway:

150°C (302 F). Full charge promotes thermal runaway

Applications:

Mobile phones, tablets, laptops, cameras

Comments

Very high specific energy, limited specific power. Cobalt is expensive. Serves as Energy Cell. Market share has stabilized.

Lithium Manganese Oxide: LiMn₂O4 cathode. graphite anode

Short form: LMO or Li-manganese (spinel structure) Since 1996

Voltages:

3.70V (3.80V) nominal; typical operating range 3.0 4.2V/cell

Specific energy (capacity):

100-150Wh/kg

Charge (C-rate)

0.7-1C typical, 3C maximum, charges to 4.20V (most cells)

Discharge (C-rate):

1C: 10C possible with some cells, 30C pulse (5s), 2.50V cut-off

Cycle life:

300-700 (related to depth of discharge, temperature)

Thermal runaway:

250°C (482°F) typical. High charge promotes thermal runway

Applications:

Power tools, medical devices, electric powertrains

Comments:

High power but less capacity: safer than Li-cobalt, commonly mixed with NMC to improve performance.

Lithium Nickel Manganese Cobalt Oxide: LiNiMnCoO₂. cathode, graphite anode Short form: NMC (NCM, CMN, CNM, MNC, MCN similar with different metal combinations) Since 2008

Voltages:

3.60V, 3.70V nominal; typical operating range 3.0 4.2V/cell, or higher

Specific energy (capacity):

150-220Wh/kg

Charge (C-rate):

0.7-1C, charges to 4.20V, some go to 4.30V; 3h charge

typical Charge current above 1C shortens battery life.

Discharge (C-rate):

1C, 2C possible on some cells; 2.50V cut-off

Cycle life:

1000-2000 (related to depth of discharge, temperature)

Thermal runaway:

210°C (410°F) typical. High charge promotes thermal

runaway

Applications:

E-bikes, medical devices, EVs, industrial

Comments:

Provides high capacity and high power. Serves as Hybrid Cell Favorite chemistry for many uses: market share is

increasing.

Lithium Iron Phosphate: LiFePO4 cathode, graphite anode

Short form: LFP or Li-phosphate. LIP is also common.

Since 1996

Voltages:

3.20, 3.30V nominal; typical operating range 2.5 3.65V/cell

Specific energy (capacity):

90-120Wh/kg

Charge (C-rate):

1C typical, charges to 3.65V; 3h charge time typical

Discharge (C-rate):

1C, 25C on some cells; 40A pulse (2s): 2.50V cut-off (lower that 2V causes damage)

Cycle life:

2000 and higher (related to depth of discharge. temperature)

Thermal runaway:

270°C (518°F) Very safe battery even if fully charged

Applications:

Portable and stationary needing high load currents and endurance

Comments:

Very flat voltage discharge curve but low capacity. One of safest Li-ions. Used for special markets. Elevated self discharge.

Lithium Nickel Cobalt Aluminum Oxide: LINICOAIO₂ cathode (-9% Co), graphite anode Short form: NCA or Li-aluminum.

Since 1999

Voltages:

3.60V nominal; typical operating range 3.0-4.2V/cell

Specific energy (capacity):

200-260Wh/kg; 300Wh/kg predictable

Charge (C-rate):

0.7C, charges to 4.20V (most cells). 3h charge typical, fast charge possible with some cells

Discharge (C-rate):

1C typical; 3.00V cut-off: high discharge rate shortens battery life

Cycle life:

500 (related to depth of discharge, temperature)

Thermal runaway:

150 °C (302 F) typical, High charge promotes thermal

runaway

Applications: Medical devices, industrial, electric powertrain (Tesla)

Comments:

Shares similarities with Li-cobalt. Serves as Energy Cell

Lithium Titanate: Cathode can be lithium manganese oxide or NMC,

Li₂ TiO3 (titanate) anode Short form: LTO or Li-titanate

since about 2008.

Voltages:

2.40V nominal: typical operating range 1.8-2.85V/cell

Specific energy (capacity):

50-80Wh/kg

Charge (C-rate):

1C typical: 5C maximum, charges to 2.85V

Discharge (C-rate):

10C possible, 30C 5s pulse: 1.80V cut-off on LCO/LTO

Cycle life:

3.000-7,000

Thermal runaway:

One of safest Li-ion batteries

Applications:

UPS, electric powertrain (Mitsubishi i-MiEV, Honda Fit EV), solar-powered street lighting

Comments:

Long life, fast charge, wide temperature range but low specific energy and expensive. Among safest Li-ion batteries.