Week 1 Understanding Different Battery Chemistry

EV LIVE BATCH 21

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.

The different Li-ion cells are,

• LCO - Lithium Cobalt Oxide (LiCoO₂)
• LMO - Lithium Manganese Oxide (LiMn₂O₄)
• NCA - Lithium Nickel Cobalt Aluminium Oxide (LiNiCoAlO₂)
• NMC - Lithium Nickel Manganese Cobalt Oxcide (LiNiMnCoO₂)
• LFP - Lithium Iron Phosphate (LiFePO₄)
• LTO - Lithium Titanate (Li₄Ti₅O₁₂)

Cell Types	Anode	Cathode	Separator	Electrolyte	Cathode Reaction	Anode Reaction	Overall Equation
LCO	Graphite Carbon	LiCoO2	Polyolefin	Ethylene Carbonate	LiCoO2 → CoO2 + Li+ + e-	6C + Li+ + e- → LiC6	LiCoO2 + 6C → LiC6 + CoO2
LMO	Graphite Carbon	LiMn2O4	Polyolefin	Lithium Halide	LiMn2O4 → Mn2O4 + Li+ + e-	6C + Li+ + e- → LiC6	LiMn2O4 + 6C → LiC6 + Mn2O4
NCA	Graphite Carbon	LiNiCoAlO2	Polyolefin	Ethylene Carbonate	LiNiCoAlO2 → NiCoAlO2 + Li+ + e-	6C + Li+ + e- → LiC6	LiNiCoAlO2 + 6C → LiC6 + NiCoAlO2
NMC	Graphite Carbon	LiNiMnCoO2	Polyolefin	Lithium Salt	LiNiMnCoO2 → NiMnCoO2 + Li+ + e-	6C + Li+ + e- → LiC6	LiNiMnCoO2 + 6C → LiC6 + NiMnCoO2
LFP	Graphite Carbon	LiFePO4	Polyolefin	Ethylene Carbonate	LiFePO4 → FePO4 + Li+ + e-	6C + Li+ + e- → LiC6	LiFePO4 + 6C → LiC6 + FePO4
LTO	Graphite Carbon	Li4Ti5O12	Polyolefin	Lithium Salt	Li4Ti5O12 → Ti5O12 + 4Li+ + 4e-	4(6C) + 4Li+ + 4e- → 4(LiC6)	Li4Ti5O12 + 4(C6) → 4(LiC6) + Ti5O12

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

Li-ion batteries can be categorised based on mainly,

- Specific energy: This defines the battery capacity in weight (Wh/kg). The capacity relates to the runtime. Products requiring long runtimes at moderate load are optimized for high specific energy.

- Specific power: It's the ability to deliver a high current and indicates loading capability. Batteries for power tools are made for high specific power and come with a reduced specific energy and vice versa.

- Performance: This measures how well the battery works over a wide range of temperatures. Most batteries are sensitive to heat and cold and require climate control. Heat reduces life, and cold lowers performance temporarily.

- Lifespan: This reflects cycle life and longevity and is related to factors such as temperature, depth of discharge, and load. Hot climates accelerate capacity loss.

- Safety: This relates to factors such as the thermal stability of the materials used in the batteries. The materials should have the ability to sustain high temperatures before becoming unstable. Instability can lead to thermal runaway in which flaming gases are vented. Fully charging the battery and keeping it beyond the designated age reduces safety.

- Cost: Demand for electric vehicles has generally been lower than anticipated and this is mainly due to the cost of lithium-ion batteries. Hence cost is a huge factor when selecting the type of lithium-ion battery.

Accordingly, Li-ion batteries are categorised,

Li-ion battery Types	Specific Energy	Specific Power	Performance	Life Span	Safety	Cost
Lithium Cobalt Oxide	High	Low	Moderate	Low	Low	Low
Lithium Manganese Oxide	Moderate	Moderate	Low	Low	Moderate	Low
Lithium Nickel Cobalt Aluminum Oxide	High	Moderate	Moderate	Moderate	Low	Moderate
Lithium Nickel Manganese Cobalt Oxide	High	Moderate	Moderate	Moderate	Moderate	Low
Lithium Iron Phosphate	Low	High	Moderate	High	High	Low
Lithium Titanate	Low	Moderate	High	High	High	High

Also, other characteristics are given as following,