Week 1 Understanding Different Battery Chemistry

Q1.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

NAME	ANODE	CATHODE	SEPERATOR	ELECTROLYTE	ANODE REACTION	CATHODE REACTION	OVERALL REACTION
Lithium Cobalt Oxide (LCO)	Graphite	Lithium Cobalt Oxide	Polyolefin	Ethylene Carbonate	LiC6 ↔ C6 + Li + e-	Co O2 + Li + e- ↔ LiCoO2	C6 + LiCo O2 ↔ LiC6 + CoO2
Lithium Manganese Oxide (LMO)	Graphite	Lithium Manganese Oxide	Polyolefin	Lithium Halide	LiC6 ↔ C6 + Li + e-	MnO2 + Li + e-  ↔ LiMnO2	C6 + LiMn2 O4 ↔ LiC6 + Mn2O4
Lithium Nickel Cobait Aluminum Oxide(NCA)	Graphite	Lithium Nickel Cobait Aluminum Oxide	Polyolefin	Ethylene Carbonate	LiC6 ↔ C6 + Li + e-	NiCoAlO2 + Li + e- ↔ LiNiCoAlO2	C6 + LiNiCoAlO2 ↔ LiC6 + NiCoAlO2
Lithium Nickel Manganese Oxide(NMC)	Graphite	Lithium Nickel Manganese Oxide	Polyolefin	Lithium Salt	LiC6 ↔ C6 + Li + e-	NiMnCoO2 + Li + e- ↔ LiNiMnCoO2	C6 + LiNiMnCoO2 ↔ LiC6 + NiMnCoO2
Lithium Iron Phosphate (LFP)	Graphite	Lithium Iron Phosphate	Polyolefin	Ethylene Carbonate	LiC6 ↔ C6 + Li + e-	FeP4 + Li + e-   ↔ LiFePO4	C6 + LiFePO4 ↔ LiC6 + FePO4
Lithium Titanate (LTO)	Graphite	Lithium Titanate	Polyolefin	Lithium Salt	Li7 Ti5 O12 ↔ Ti5 O12 + 4Li + 4e-	4Mn2O4 + 4Li + 4e- ↔ 4LiMn2O4	4Mn2O4 + Li4Ti5O12 ↔ 4LiMn2O4 + Ti5O12

1.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).

The drawback of Li-cobalt is a relatively short life span, low thermal stability and limited load capabilities (specific power). Like other cobalt-blended Li-ion, Li-cobalt has a graphite anode that limits the cycle life by a changing solid electrolyte interface (SEI), thickening on the anode and lithium plating while fast charging and charging at low temperature. Newer systems include nickel, manganese and/or aluminum to improve longevity, loading capabilities and cost.

2.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 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 high thermal stability and enhanced safety, but the cycle and calendar life are limited.

Low internal cell resistance enables fast charging and high-current discharging. In an 18650 package, Li-manganese can be discharged at currents of 20–30A with moderate heat buildup. It is also possible to apply one-second load pulses of up to 50A. A continuous high load at this current would cause heat buildup and the cell temperature cannot exceed 80°C (176°F). Li-manganese is used for power tools, medical instruments, as well as hybrid and electric vehicles.

3.Lithium Nickel Cobalt Aluminum Oxide (LiNiCoAlO₂) — NCA:-

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. Less flattering are safety and cost. summarizes the six key characteristics. NCA is a further development of lithium nickel oxide; adding aluminum gives the chemistry greater stability.

4.Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO₂) — NMC:-

One of the most successful Li-ion systems is a cathode combination of nickel-manganese-cobalt (NMC). Similar to Li-manganese, these systems can be tailored to serve as Energy Cells or Power Cells. For example, 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. A silicon-based anode will go to 4,000mAh and higher but at reduced loading capability and shorter cycle life. Silicon added to graphite has the drawback that the anode grows and shrinks with charge and discharge, making the cell mechanically unstable.

The secret of NMC lies in combining nickel and manganese. An analogy of this is table salt in which the main ingredients, sodium and chloride, are toxic on their own but mixing them serves as seasoning salt and food preserver. Nickel is known for its high specific energy but poor stability; manganese has the benefit of forming a spinel structure to achieve low internal resistance but offers a low specific energy. Combining the metals enhances each other strengths.

5.Lithium Iron Phosphate(LiFePO₄) — LFP:-

In 1996, the University of Texas (and other contributors) discovered phosphate as cathode material for rechargeable lithium batteries. Li-phosphate offers good electrochemical performance with low resistance. 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. With most batteries, cold temperature reduces performance and elevated storage temperature shortens the service life, and Li-phosphate is no exception. Li-phosphate has a higher self-discharge than other Li-ion batteries, which can cause balancing issues with aging. This can be mitigated by buying high quality cells and/or using sophisticated control electronics, both of which increase the cost of the pack. Cleanliness in manufacturing is of importance for longevity. There is no tolerance for moisture, lest the battery will only deliver 50 cycles. 

6.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 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 (–22°F).

Q2.Compare the differences between each type of Li+ion batteries based on their characteristics

What is a lithium-ion battery:- A lithium-ion battery is a rechargeable battery that can be charged multiple times as a power source for electronic devices and electric vehicles and used in other applications such as stationary battery energy storage systems (BESSs) and uninterruptible power supplies (UPSs).

During the charging phase in a lithium-ion battery, lithium ions move from the positive side of the battery to the negative side. In contrast, the ions move in the reverse direction during the discharging phase.

Six types of lithium-ion batteries :-

• SP stands for specific power
• SE stands for specific energy
• SF stands for safety
• LS stands for lifespan
• CS stands for cost
• PF stands for performance
• L stands for low
• M stands for moderate
• H stands for high

Chemistry	Nominal Voltage[V]	Energy Density[Wh/kg]	Cycles Life[cycles]	Properties	Applications
LCO[Lithium Cobalt Oxide]	3.7	110-190	500-1000	High safety risk, good lifetime	used in portable electronic devices
LMO[Lithium Manganese Oxide]	3.8	100-120	1000	Cheaper, safer than LiCoO2 and LiNiO2	used in car audio applications and mobile medical devices
NCA[Lithium Nickel Cobalt Aluminium]	3.6	100-150	2000-3000	High Energy, High Density, Expensive	–
NMC[Lithium Nickel Manganese Oxide]	3.6	100-170	2000-3000	High Voltage, Good Specific Capacity, High Safety Risk, Good Lifetime	used in electric cars are portable electronics
LFP[Lithium Iron Phosphate]	3.3	90-115	>3000	Long Lifetime, High Stability, Basic Low Cost	good potential replacement for lead-acid batteries in applications such as automotive and solar applications
LTO[Lithium Titanate Oxide]	2.2	60-75	>5000	Negligible Volume Expansion, Basic low cost, Stable electrochemical operation, high thermal stability	used in car audio applications as well as mobile medical d

​Differences Between Each Type Of Li+ion Batteries:-

Cell chemistry	Also known as	Electrode		Re­charge­able	Com­mercial­ized	Voltage			Energy density		Specific power	Cost†	Thermal runaway	Self-discharge rate	Shelf life
		Anode	Cathode			Cutoff	Nominal	100% SOC	by mass	by volume
					year	V	V	V	MJ/kg (Wh/kg)	MJ/L (Wh/L)	W/kg	Wh/$ ($/kWh)	°C	%/month	years
Lithium–titanate (LTO)	Li 4Ti 5O 12 LTO	Lithium	Lithium manganese oxide or Lithium nickel manganese cobalt oxide	Yes	2008	1.6–1.8	2.3–2.4	2.8	0.22–0.40 (60–110)	0.64 (177)	3,000–5,100	0.44 (2258)	One of safest Li-ion batteries	2–5	10–20
Lithium cobalt oxide (LCO)	LiCoO 2 ICR LCO Li‑cobalt	Graphite‡	Lithium cobalt oxide	Yes	1991	2.5	3.7	4.2	0.70 (195)	2.0 (560)		2.48 (403)	150	5-10
Lithium iron phosphate (LFP)	LiFePO 4 IFR LFP Li‑phosphate	Graphite‡	Lithium iron phosphate	Yes	1996	2	3.2	3.65	0.32–0.58 (90–160)	1.20 (333)	200–1'200		270	4.5	20 years[57]
Lithium manganese oxide (LMO)	LiMn 2O 4 IMR LMO Li‑manganese	Graphite‡	Lithium manganese oxide	Yes	1999	2.5	3.9	4.2	0.54 (150)	1.5 (420)		2.48 (403)	250
Lithium nickel cobalt aluminium oxides (NCA)	LiNiCoAlO 2 NCA NCR Li‑aluminium	Graphite‡	Lithium nickel cobalt aluminium oxide	Yes	1999	3.0	3.6	4.3	0.79 (220)	2.2 (600)			150
Lithium nickel manganese cobalt oxide (NMC)	LiNi xMn yCo 1-x-yO 2 INR NMC NCM	Graphite‡	Lithium nickel manganese cobalt oxide	Yes	2008	2.5	3.6	4.2	0.74 (205)	2.1 (580)			210