Week 1 Understanding Different Battery Chemistry

Comparison table of different properties of Batteries:

Lithium Cobalt Oxide(LCO):

• Cathode Material: Lithium Cobalt Oxide (LiCoO2)
• Anode Material: Graphitic Carbon
• Electrolyte: tetrafluoroterephthalonitrile (TFTPN)
• Crystal Structure: Layered
• Average Voltage per cell: 3.8
• Reaction at Cathode: CoO₂ + Li⁺ + e^- → LiCoO₂
• Reaction at Anode: LiC₆ → C₆ + Li⁺ + e^-
• Overall reaction: LiC₆ + CoO₂ ⇄ C₆ + LiCoO₂
• Life cycle: 500-1000 cycles depending upon the charging and discharging rate and operating temperature.
• Uses: Cell phones, Laptops, etc.

Lithium Manganese Oxide(LMO):

• Cathode Material: Manganese Oxide(MnO2)
• Anode Material: Lithium Metal
• Electrolyte: Lithium Halide dissolved in Organic solvent
• Crystal Structure: Layered
• Average Voltage per cell: 3.3
• Reaction at cathode: MnO₂+Li⁺+e^- → MnOOLi
• Reaction at Anode: Li → Li⁺+e^-
• Overall reaction: MnO₂+Li → MnOOLi
• Life cycle: 300-700 cycles depending upon the charging and discharging rate and operating temperature.
• Uses: Powertools, Watches, Calculators, Automatic cameras, etc.

Lithium Nickel Cobalt Aluminium Oxide (NCA):

• Cathode Material: Lithium Nickel Cobalt Aluminium Oxide (LiNiCoAlO₂)
• Anode Material: Silicon suboxide-enhanced graphite
• Electrolyte: Ethylene Carbonate, Dimethyl Carbonate as a solvent, and salt of Lithium hexafluorophosphate
• Crystal Structure: Layered
• Average Voltage per cell: 3.7
• Reaction at Cathode: NiCoAlO₂ + Li⁺ + e^- → LiNiCoAlO₂
• Reaction at Anode: LiC₆ → C₆ + Li⁺ + e^-
• Overall reaction: NiCoAlO₂ + LiC₆ → C₆ + LiNiCoAlO₂
• Life cycle: 500 cycles depending upon the charging and discharging rate and operating temperature.
• Uses: Medical devices, industrial, electric powertrain (Tesla)

Lithium Nickel Manganese Cobalt Oxide (NMC):

• Cathode Material: Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO₂)
• Anode Material: Graphite
• Electrolyte: Ethylene Carbonate, Dimethyl Carbonate as a solvent, and salt of Lithium hexafluorophosphate
• Crystal Structure: Layered
• Average Voltage per cell: 3.7
• Reaction at Cathode: NiMnCoO₂ + Li⁺ + e^- → LiNiMnCoO₂
• Reaction at Anode: LiC₆ → C₆ + Li⁺ + e^-
• Overall reaction: NiMnCoO₂ + LiC₆ → C₆ + LiNiMnCoO₂
• Life cycle: 1000-2000 cycles depending upon the charging and discharging rate and operating temperature.
• Uses: Electric Vehicles, Hybrid Vehicles, Power Train

Lithium Iron Phosphate (LFP)

• Cathode Material: lithium iron phosphate (LiFePO4)
• Anode Material: lithiated porous graphite
• Electrolyte: Ethylene Carbonate, Dimethyl Carbonate as a solvent, and salt of Lithium hexafluorophosphate
• Crystal Structure: Olivine
• Average Voltage per cell: 3.4
• Reaction at Cathode: Li_yFePo₄ + xLi⁺ + xe^- → Li_x+yFePo₄
• Reaction at Anode: Li_xC₆ → C₆ + xLi⁺ + xe^-
• Overall reaction: Li_yFePo₄ + Li_xC₆ ⇄ C₆ + Li_x+yFePo₄
• Life cycle: 2000 and higher
• Uses: Portable and stationary needing high load currents and endurance

Lithium Titanate Oxide (LTO)

• Cathode Material: LMO or NMC
• Anode Material: Lithium Titanate Oxide (Li₄Ti₅O₁₂)
• Electrolyte: Ethylene Carbonate, Dimethyl Carbonate as a solvent, and salt of Lithium hexafluorophosphate
• Crystal Structure: Spinel
• Average Voltage per cell:2.4
• Reaction at Cathode: 4Mn₂O₄+4Li⁺+4e^- → 4LiMn₂O₄
• Reaction at Anode: Li₄Ti₅O₁₂ → 4Li⁺ + Ti₅O₁₂ + 4e^-
• Overall reaction: Li₄Ti₅O₁₂ + 4Mn₂O₄ → 4LiMn₂O₄ + Ti₅O₁₂
• Life cycle: 3,000–7,000
• Uses: UPS, electric powertrain (Mitsubishi i-MiEV, Honda Fit EV), solar-powered street lighting

Comparison based on the characteristics of the batteries:

Lithium Cobalt Oxide has high specific energy as compared to the other batteries which makes it the preferred choice for laptops and mobile phones. It also has a low cost and a moderate performance. However, it is highly unfavorable in all the other aspects when compared to the other lithium-ion batteries. It has a low specific power, low safety, and a low lifespan.

Lithium Manganese Oxide has a moderate specific power, moderate specific energy, and a moderate level of safety when compared to the other types of lithium-ion batteries. It has the added advantage of a low cost. The downsides are its low performance and low lifespan. It is usually used in medical devices and power tools.

Lithium Nickel Cobalt Aluminum Oxide offers one strong advantage as compared to the five other batteries and that is high specific energy. It is pretty moderate in the rest of the characteristics like performance, cost, specific power, and lifespan. The only downside to this battery type is its low level of safety. Its high specific energy and moderate lifespan make it a good candidate for electric powertrains.

Lithium Nickel Manganese Cobalt Oxide has two major advantages as compared to the other batteries. The first one is its high specific energy which makes it desirable in electric powertrains, electric vehicles, and electric bikes. The other is its low cost. It is moderate in terms of specific power, safety, lifespan, and performance when compared to other lithium-ion batteries. It can be optimized to either have high specific power or high specific energy.

Lithium Iron Phosphate only has one major disadvantage when compared to other types of lithium-ion batteries and that is its low specific energy. Other than that, it has moderate to high ratings in all the other characteristics. It has a high specific power, offers a high level of safety, has a high lifespan, and comes at a low cost. The performance of this battery is also moderate. It is often employed in electric motorcycles and other applications that require a long lifespan and a high level of safety.

Lithium Titanate offers high safety, high performance, and a high lifespan which are very important features every battery should have. Its specific energy is low compared to the five other lithium-ion batteries but it compensates for this with a moderate specific power. The only major disadvantage of lithium titanate as compared to the other lithium-ion batteries is its extremely high cost. Another important feature of this battery worthy of mention is its remarkably fast recharge time. It can be used for storing solar energy and creating smart grids.

Table representing the above information:

• 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