Week 1 Understanding Different Battery Chemistry
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 of it.
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Battery type |
Cathode Material |
Anode Material |
Electrolyte Material |
Separator Material |
Anode reaction |
Cathode Reaction |
Overall reaction |
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LMO |
Lithium manganese oxide |
Graphite |
Lithium manganese |
Polyolefin |
LiC6 ⟺ C6 + Li + + e- |
MnO2 + Li+ + e_ ⟺ LiMnO2 |
C6+ LiMnO2 ⟺ LiC6 + MnO2 |
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LCO |
Lithium cobalt oxide |
Ethylene carbonate |
LiC6 ⟺ C6 + Li + + e- |
CoO2 + Li+ + e- ⟺ LiCoO2 |
C6+ LiCoO2 ⟺ LiC6 + CoO2 |
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NCA |
Lithium nickel cobalt oxide |
Ethylene carbonate |
LiC6 ⟺ C6 + Li + + e- |
NiCoAiO2 + Li+ + e_ ⟺ LiNiCoAiO2 |
C6+ LiNiCoAiO2 ⟺ LiC6 + NiCoAiO2 |
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NMC |
Graphite manganese cobalt oxide |
Lithium manganese |
LiC6 ⟺ C6 + Li + + e- |
NiMnCoO2 + Li+ + e_ ⟺ LiNiMnCoO2 |
C6+ LiNiMnCoO2 ⟺ LiC6 + NiMnCoO2 |
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LIP |
Lithium iron phosphate |
Ethylene carbonate |
LiC6 ⟺ C6 + Li + + e- |
FePO4 + Li+ + e_ ⟺ LiFePO4 |
C6+ LiFePO4 ⟺ LiC6 + FePO4 |
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|
LTO |
Lithium titanate oxide |
Lithium manganese |
Li4Ti3O12 ⟺ Ti3O12 + 4Li + + 4e- |
4Mn2O4 + 4Li+ + 4e- ⟺ 4LiMn2O4 |
4Mn2O4 + Li4Ti3O12⟺ 4LiMn2O4 + Ti3O12 |
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)
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.
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.
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.
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
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).
Future Batteries :
- Solid-state Li-ion: High specific energy but poor loading and safety.
- Lithium-sulfur: High specific energy but poor cycle life and poor loading
- Lithium-air: High specific energy but poor loading, needs clean air to breath and has short life.
2.Compare the differences between each type of Li+ion batteries based on their characteristics
Lithium Cobalt Oxide(LiCoO2) — LCO
Li-cobalt excels on high specific energy but offers only moderate performance-specific power, safety and life span.
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Lithium Cobalt Oxide: LiCoO2 cathode (~60% Co), graphite anode |
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Voltages |
3.60V nominal; typical operating range 3.0–4.2V/cell |
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Specific energy (capacity) |
150–200Wh/kg. Specialty cells provide up to 240Wh/kg. |
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Charge (C-rate) |
0.7–1C, charges to 4.20V (most cells); 3h charge typical. Charge current above 1C shortens battery life. |
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Discharge (C-rate) |
1C; 2.50V cut off. Discharge current above 1C shortens battery life. |
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Cycle life |
500–1000, related to depth of discharge, load, temperature |
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Thermal runaway |
150°C (302°F). Full charge promotes thermal runaway |
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Applications |
Mobile phones, tablets, laptops, cameras |
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Comments |
Very high specific energy, limited specific power. Cobalt is expensive. Serves as Energy Cell. Market share has stabilized. |
Lithium Manganese Oxide (LiMn2O4) — LMO
Although moderate in overall performance, newer designs of Li-manganese offer improvements in specific power, safety and life span
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Lithium Manganese Oxide: LiMn2O4 cathode. graphite anode |
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Voltages |
3.70V (3.80V) nominal; typical operating range 3.0–4.2V/cell |
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Specific energy (capacity) |
100–150Wh/kg |
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Charge (C-rate) |
0.7–1C typical, 3C maximum, charges to 4.20V (most cells) |
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Discharge (C-rate) |
1C; 10C possible with some cells, 30C pulse (5s), 2.50V cut-off |
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Cycle life |
300–700 (related to depth of discharge, temperature) |
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Thermal runaway |
250°C (482°F) typical. High charge promotes thermal runaway |
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Applications |
Power tools, medical devices, electric powertrains |
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Comments |
High power but less capacity; safer than Li-cobalt; commonly mixed with NMC to improve performance. |
Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2) — NMC
NMC has good overall performance and excels on specific energy.
This battery is the preferred candidate for the electric vehicle and has the lowest self-heating rate.
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Lithium Nickel Manganese Cobalt Oxide: LiNiMnCoO2. cathode, graphite anode |
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Voltages |
3.60V, 3.70V nominal; typical operating range 3.0–4.2V/cell, or higher |
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Specific energy (capacity) |
150–220Wh/kg |
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Charge (C-rate) |
0.7–1C, charges to 4.20V, some go to 4.30V; 3h charge typical. Charge current above 1C shortens battery life. |
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Discharge (C-rate) |
1C; 2C possible on some cells; 2.50V cut-off |
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Cycle life |
1000–2000 (related to depth of discharge, temperature) |
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Thermal runaway |
210°C (410°F) typical. High charge promotes thermal runaway |
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Cost |
~$420 per kWh[1] |
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Applications |
E-bikes, medical devices, EVs, industrial |
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Comments 2019 Update: |
Provides high capacity and high power. Serves as Hybrid Cell. Favorite chemistry for many uses; market share is increasing. |
Lithium Iron Phosphate(LiFePO4) — LFP
Li-phosphate has excellent safety and long life span but moderate specific energy and elevated self-discharge.
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Lithium Iron Phosphate: LiFePO4 cathode, graphite anode |
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Voltages |
3.20, 3.30V nominal; typical operating range 2.5–3.65V/cell |
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Specific energy (capacity) |
90–120Wh/kg |
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Charge (C-rate) |
1C typical, charges to 3.65V; 3h charge time typical |
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Discharge (C-rate) |
1C, 25C on some cells; 40A pulse (2s); 2.50V cut-off (lower that 2V causes damage) |
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Cycle life |
2000 and higher (related to depth of discharge, temperature) |
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Thermal runaway |
270°C (518°F) Very safe battery even if fully charged |
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Cost |
~$580 per kWh[1] |
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Applications |
Portable and stationary needing high load currents and endurance |
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Comments |
Very flat voltage discharge curve but low capacity. One of safest Li-ions. |
Lithium Nickel Cobalt Aluminum Oxide (LiNiCoAlO2) — NCA
High energy and power densities, as well as good life span, make NCA a candidate for EV powertrains. High cost and marginal safety are negatives.
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Lithium Nickel Cobalt Aluminum Oxide: LiNiCoAlO2 cathode (~9% Co), graphite anode |
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Voltages |
3.60V nominal; typical operating range 3.0–4.2V/cell |
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Specific energy (capacity) |
200-260Wh/kg; 300Wh/kg predictable |
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Charge (C-rate) |
0.7C, charges to 4.20V (most cells), 3h charge typical, fast charge possible with some cells |
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Discharge (C-rate) |
1C typical; 3.00V cut-off; high discharge rate shortens battery life |
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Cycle life |
500 (related to depth of discharge, temperature) |
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Thermal runaway |
150°C (302°F) typical, High charge promotes thermal runaway |
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Cost |
~$350 per kWh[1] |
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Applications |
Medical devices, industrial, electric powertrain (Tesla) |
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Comments |
Shares similarities with Li-cobalt. Serves as Energy Cell. |
Lithium Titanate (Li2TiO3) — LTO
Li-titanate excels in safety, low-temperature performance and life span. Efforts are being made to improve the specific energy and lower cost
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Lithium Titanate: Cathode can be lithium manganese oxide or NMC; Li2TiO3 (titanate) anode |
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Voltages |
2.40V nominal; typical operating range 1.8–2.85V/cell |
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Specific energy (capacity) |
50–80Wh/kg |
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Charge (C-rate) |
1C typical; 5C maximum, charges to 2.85V |
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Discharge (C-rate) |
10C possible, 30C 5s pulse; 1.80V cut-off on LCO/LTO |
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Cycle life |
3,000–7,000 |
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Thermal runaway |
One of safest Li-ion batteries |
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Cost |
~$1,005 per kWh[1] |
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Applications |
UPS, electric powertrain (Mitsubishi i-MiEV, Honda Fit EV), solar-powered street lighting |
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Comments |
Long life, fast charge, wide temperature range but low specific energy and expensive. |
Typical specific energy of lead-, nickel- and lithium-based batteries.