Week 1 Understanding Different Battery Chemistry
Understanding different battery chemistry
(1) Prepare a table that includes materials & chemical reactions occurring at the anode and cathode of LCO, LMO, NCA, NMC, LFP and LTO type of lithium-ion cells.
SOLUTION:
|
Lithium-ion battery type
|
Abbreviation
|
Chemistry Name
|
Material |
Chemical Reaction
|
|
| Cathode | Anode | ||||
| Lithium Nickel Manganese Cobalt oxide | NMC | `LiNiMnCoO_2` | Nickel, Manganese and cobalt | Graphite carbon | `Li_1-xMO_2 + LiC_6 <=> Li_(1-x)MO_2 + C_6` |
| Lithium Nickel Cobalt Aluminium | NCA | `LiNiCoAlO_2` | Nickel, Cobalt, Aluminium | Graphite carbon | `Li_(1-x)MO_2 + LiC_6 <=> Li_(1-x)MO_2 + C_6` |
| Lithium Manganese Oxide | LMO | `MnO_2` | Manganese | Graphite carbon | `LiC_6 + Mn_(2)O_4 <=>C_6 + LiMnO_2` |
| Lithium Iron Phosphate | LFP | `LiFePO_4` | Iron Phosphate | Graphite carbon | `LiFePO_4 + 6C <=> LiC_6 + FePO_4` |
| Lithium Cobalt Oxide | LCO | `LiCoO_2` | Cobalt | Graphite carbon | LixC6 + Li1-xCoO2"}"2":513,"3":{"1":0},"12":0}">`C_6+ LiCoO_2 <=> Li_(x)C_6 + Li_(1-x)CoO_2` |
| Lithium Titanium Oxide | LTO | `Li_2TiO_3` | Lithium Titanate | Graphite carbon | `Li_(4)Ti_(5)O_(12) + 4Mn_(2)O_4 <=> 4LiMn_(2)O_4 + Ti_(5)O_(12)` |
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(2) Compare the differences between each type of Li+ion batteries based on their characteristics.
SOLUTION:
Comparisons of different types of Li-ion batteries used in EVs from the following perspectives:
- Specific energy (capacity): 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 high current and indicates loading capability. Batteries for power tools are made for high specific power and come with a reduced specific energy.
- 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.
- Performance: This measures how well the battery works over a wide range of temperature. Most batteries are sensitive to heat and cold and require climate control. Heat reduces life, and cold lowers the performance temporarily.
- Life span: This reflects cycle life and longevity and is related to factors such as temperature, depth of discharge and load. Hot climates accelerate capacity loss. Cobalt blended lithium ion also usually have a graphite anode that limits the cycle life.
- 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.
Fig. Characteristics of different types of Lithium-ion battery
| Lithium-ion battery types | Specific Power | Specific Energy | Safety | Lifespan | Cost | Performance |
| Lithium Cobalt oxide | Low | High | Low | Low | Low | Medium |
| Lithium Manganese Oxide | Medium | Medium | Medium | Low | Low | Low |
| Lithium Nickel Manganese Cobalt Oxide | Medium | High | Medium | Medium | Low | Medium |
| Lithium Iron Phosphate | High | Low | High | High | Low | Medium |
| Lithium Nickel Cobalt Aluminum Oxide | Medium | High | Low | Medium | Medium | Medium |
| Lithium Titanate | Medium | Low | High | High | High | High |
Lithium Nickel Manganese Cobalt Oxide (NMC), Lithium Iron Phosphate (LiFePO4) and Lithium Manganese Oxide stand out as being superior among these six candidates.
Reference:
- https://www.powerelectronics.com/technologies/alternative-energy/article/21864146/six-lithiumion-battery-chemistries-not-all-batteries-are-created-equal
- https://evduniya.com/ev-global/types-of-batteries-used-in-electric-vehicles-their-parameters.html
- https://www.google.com/search?q=chemical+reaction+in+NMC+battery&rlz=1C1CHBF_enIN818IN818&oq=chemical+reaction+in+NMC+battery&aqs=chrome..69i57j33i22i29i30.11280j0j7&sourceid=chrome&ie=UTF-8
- Lithium-Ion battery comparison
- Graphical representation of Lithium-ion battery characteristics