Week 1 Understanding Different Battery Chemistry

1)

A lithium-ion battery is a secondary type of battery which are commonly used in portable electronics & electric vehicles. Similar to a conventional battery, a Lithium-ion battery includes a cathode(+ve electrode), anode(-ve electrode), & electrode as conductor. The cathode is a metal oxide material & anode consists of porous carbon. During the discharging process, the ions flow from the anode to the cathode through the separator & electrons flow from the cathode to the anode. similarly, the opposite happens during the charging process.

Materials & chemical reactions occurring at the anode and cathode of LCO, LMO, NCA, NMC, LFP and LTO type of lithium ion cells are as shown below table.

TYPES	ANODE	SEPARATOR	CATHODE MATERIAL	ELECTROLYTE	ANODE REACTION	CATHODE REACTION	OVERALL REACTION
Lithium Cobalt Oxides (LCO)	Graphite	Polyolefin	Lithium Cobalt Oxides	Ethylene carbonate	LiC6↔C6+Li++e-	CoO2+Li++e+↔LiCoO2	C6 + LiCoO2↔ LiC6+ CoO2
Lithium Manganese Oxide (LMO)	Graphite	Polyolefin	Lithium Manganese	Lithium halide	LiC6↔C6+Li++e-	MnO2 +Li++e+↔LiMnO2	C6 +LiMn2O4↔LiC6+ Mn2O4
Lithium Nickle Cobalt Aluminium Oxide (NCA)	Graphite	Polyolefin	Nickle Cobalt Aluminium	Ethylene carbonate	LiC6↔C6+Li+e-	NiCoAlO2 + Li++e+↔LiNiCoAlO2	C6 + LiNiCoAlO2 ↔ LiC6+ NiCoAlO2
Lithium Nickle Manganese Cobalt Oxide (NMC)	Graphite	Polyolefin	Nickle Manganese	Lithium salt	LiC6↔C6+Li+e-	NiMnCoO2 + Li++e+↔LiNiMnCoO2	C6 + LiNiMnCoO2 ↔ LiC6+ NiMnCoO2
Lithium Iron Phosphate (LFP)	Graphite	Polyolefin	Lithium Iron Phosphate	Ethylene carbonate	LiC6↔C6+Li+e-	FePO4 + Li++e+↔ LifePO4	C6 + LifePO4↔ LiC6+ FePO4
Lithium Titanite (LTO)	Graphite	Polyolefin	Lithium Titanite	Lithium salt	Li4Ti5O12↔ Ti5O12+4Li+4e-	4Mn2O4 + 4Li++4e+↔4LiMn2O4	4Mn2O4 + Li4Ti5O12↔4LiMn2O4 +Ti5O12

2) Comparisons of different types of Li-ion batteries used in EVs from the following perspectives:

1. Specific energy (Capacity)
2. Specific power
3. Safety
4. Performance
5. Life span
6. Cost

The above fig. shows that Lithium Nickel Manganese Cobalt Oxide (NMC), Lithium Iron Phosphate (LiFePO4), and Lithium Manganese Oxide stand out as being superior among these six types.