Week 1 Understanding Different Battery Chemistry
AIM:
1.To 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
2.To Compare the differences between each type of Li+ion batteries based on their characteristics.
Battery:
A battery is a device which converts chemical energy contained within its active materials directly into electrical energy by means of electrochemical Oxidation-Reduction (Redox) reaction. This type of reaction involves the transfer of eectrons from one material to another via an electric circuit. It consisting of one or more electrochemical cells with external connections for powering electrical devices such as flashlights, mobile phones, and electric cars. When a battery is supplying electric power, its positive terminal is the cathode and its negative terminal is the anode.
Types of Batteries:
Batteries are basically two types:
- Primary Batteries (Non-Rechargeable Batteries): These are known as one time used batteries, because they can not rechargeable.
- Secondary Batteries (Rechargeable Batteries): These are known as reusable batteries, because they can rechargeable.
During discharge the electrons flow from anode to cathode i.e.; the flow of current is from cathode to anode. Vice-versa during charging.
Lithium-ion Battery:
Lithium-ion is named for its active materials; the words are either written in full or shortened by their chemical symbols. A series of letters and numbers strung together can be hard to remember and even harder to pronounce, and battery chemistries are also identified in abbreviated letters.
Types of Lithium ion Battery Technologies:
- Lithium Cobalt Oxide (LCO)
- Lithium Manganies Oxide (LMO)
- Lithium Nickel Cobalt Aluminium (NCA)
- Nickel Manganies Cobalt (NMC)
- Lithium Titanite (LTO)
- Lithium Iron Phospate (LFP)
Chemical Reactions of Li-ion Cells:
LCO:
Anode Reaction (Discharge): Li+C6→xLi++C6+xe-">Li+C6→xLi++C6+xe−Li+C6→xLi++C6+xe-
Cathode Reaction (Discharge): Li1-x+CoO2+xLi+xe-→LiCoO2">Li1−x+CoO2+xLi+xe−→LiCoO2Li1-x+CoO2+xLi+xe-→LiCoO2
Overal Reaction: C6+LiCoO2⇔LixC6+Li1-xCoO2">C6+LiCoO2⇔LixC6+Li1−xCoO2C6+LiCoO2⇔LixC6+Li1-xCoO2
LMO:
Anode Reaction (Discharge): Li+C6→xLi++C6+xe-">Li+C6→xLi++C6+xe−Li+C6→xLi++C6+xe-
Cathode Reaction (Discharge): Li1-x+Mn2O4+xLi+xe-→LiMnO2">Li1−x+Mn2O4+xLi+xe−→LiMnO2Li1-x+Mn2O4+xLi+xe-→LiMnO2
Overal Reaction: LiC6+Mn2O4⇔C6+LiMnO2">LiC6+Mn2O4⇔C6+LiMnO2LiC6+Mn2O4⇔C6+LiMnO2
NMC:
Anode Reaction (Discharge): Li+C6→xLi++C6+xe-">Li+C6→xLi++C6+xe−Li+C6→xLi++C6+xe-
Cathode Reaction (Discharge): Li1-x+MO2+xLi++xe_→LiMO2">Li1−x+MO2+xLi++xe_→LiMO2Li1-x+MO2+xLi++xe_→LiMO2
Overal Reaction: Li1-x+MO2+LiC6⇔Li1-xMO2+C6">Li1−x+MO2+LiC6⇔Li1−xMO2+C6Li1-x+MO2+LiC6⇔Li1-xMO2+C6
LFP:
Anode Reaction (Discharge): Li+C6→xLi++C6+xe-">Li+C6→xLi++C6+xe−Li+C6→xLi++C6+xe-
Cathode Reaction (Discharge): LiFe3PO4+xLi++xe+→LiFe2PO4">LiFe3PO4+xLi++xe+→LiFe2PO4LiFe3PO4+xLi++xe+→LiFe2PO4
Overal Reaction: LiFePO4+6C⇔LiC6+FePO4">LiFePO4+6C⇔LiC6+FePO4LiFePO4+6C⇔LiC6+FePO4
NCA:
Anode Reaction (Discharge): Li+C6→xLi++C6+xe-">Li+C6→xLi++C6+xe−Li+C6→xLi++C6+xe-
Cathode Reaction (Discharge): Li1-x+MO2+xLi++xe_→LiMO2">Li1−x+MO2+xLi++xe_→LiMO2Li1-x+MO2+xLi++xe_→LiMO2
Overal Reaction: Li1-xMO2+LiC6⇔Li1-xMO2+C6">Li1−xMO2+LiC6⇔Li1−xMO2+C6Li1-xMO2+LiC6⇔Li1-xMO2+C6
LTO:
Anode Reaction (Discharge): Li+C6→xLi++C6+xe-">Li+C6→xLi++C6+xe−Li+C6→xLi++C6+xe-
Cathode Reaction (Discharge): 4Mn2O4+4Li++4e_→4LiMn2O4">4Mn2O4+4Li++4e_→4LiMn2O44Mn2O4+4Li++4e_→4LiMn2O4
Overal Reaction: Li4Ti5O2+4Mn2O4⇔4LiMn2O4+Ti5O12">Li4Ti5O2+4Mn2O4⇔4LiMn2O4+Ti5O12Li4Ti5O2+4Mn2O4⇔4LiMn2O4+Ti5O12
| Lithium ion types | LCO | LMO | NMC | LFP | NCA | LTO |
| Chemical name | LiCoO2">LiCoO2LiCoO2 | LiMn2O4">LiMn2O4LiMn2O4 | LiNiMnCoO2">LiNiMnCoO2LiNiMnCoO2 | LiFePO4">LiFePO4LiFePO4 | LiNiCoAlO2">LiNiCoAlO2LiNiCoAlO2 | Li2TiO3">Li2TiO3Li2TiO3 |
| Anode Material | Graphite | Graphite | Graphite | Graphite | Graphite | Li2TiO3">Li2TiO3Li2TiO3 (Titanate) |
| Cathode Material | LiCoO2(≈60%Co)">LiCoO2(≈60%Co)LiCoO2(≈60%Co) | LiMn2O4">LiMn2O4LiMn2O4 | LiNiMnCoO2">LiNiMnCoO2LiNiMnCoO2 | LiFePO4">LiFePO4LiFePO4 | LiNiCoAlO2(≈9%Co)">LiNiCoAlO2(≈9%Co)LiNiCoAlO2(≈9%Co) | Li">LiLiManganese oxide |
| Electrolyte | Ethylene Carbonate | Lithium Halide | Lithium Salt | Ethynal Carbonate | Ethynal Carbonate | Lithium Salt |
| Separator | Polyolefin | Polyolefin | Polyolefin | Polyolefin | Polyolefin | Polyolefin |
| Nomial Voltage | 3.6V | 3.7V, 3.8V | 3.6V, 3.7V | 3.2V, 3.3V | 3.6V | 2.4V |
| Operating Range | Typical range 3 V- 4.2V/cell | 3V - 4.2V/cell | 3V - 4.2V/cell or higher | 2.5V - 3.65V/cell | 3V - 4.2V/cell | 1.8V - 2.85V/cell |
| Energy Capacity |
150-200Wh/kg. Specialty cells provide up to 240Wh/kg |
100-150Wh/kg | 150-220 Wh/kg | 90-120Wh/kg | 200-260Wh/kg; 300Wh/kg pedictable | 50-80Wh/kg |
| Life Cycle | 500-1000 | 300-700 | 1000-2000 | 2000 & higher | 500 | 3000-7000 |
| Thermal Runaway | 1500C(3020F)">1500C(3020F)1500C(3020F) | 2500C(4820F)">2500C(4820F)2500C(4820F)typical | 2100C(4100F)">2100C(4100F)2100C(4100F)tipical | 2700C(5180F)">2700C(5180F)2700C(5180F) | 1500C(3020F)">1500C(3020F)1500C(3020F) | One of safest Li-ion cells |
| Charge (C-rate) |
0.7-1C, charges to 4.2V (most cells); 3h charge typical. Charge current above 1C shortens battery life. |
0.7-1C, typical, 3C maximum, changes to 4.2V (most cells) |
0.7-1C, charges to 4.2V (most cells); 3h charge typical. Charge current above 1C shortens battery life. |
1C typical, charges to 3.65V; 3h charge time typical | 0.7C, charges to 4.2V (most cells), 3h charge time typical | 1C typical; 5C aximum, changes to 2.85V |
| Discharge (C-rate) | 1C; 2.5V cut-off. Discharge current above 1C shortens battery life. | 1C; 10C possible with some cells, 30C pulse (5s), 2.5V cut-off. | 1C;2C possible on some cells; 2.5V cut-off | 1C, 250C on some cells; 40A pulse (2s); 2.5V cut-off (lower that 2V) causes damage) | 1C typical; 3V cut-off; high discharge rate shortens battery life | 10C possible, 30C 5s pulse; 1.8V cut-off on LCO/LTO |
| Applications | Mobile phones, Laptops, cameras | Power tools, Medical devices, Electric powertrains | E-bikes, medical devices, EVs, industrial | Portable and stationary needing high load currents and endurance | Medical Medical devices, Electric powertrains (Tesla) | UPS, Electric powertrains (Mitsubishi i-MiEV, Honda Fit EV), solar-power street lighting |
| Comments (Advantages & Drawbacks) |
Very high specific energy, limited specific power. Cobalt is expensive. Serves as energy call. Market share has stabilised. |
High power but less capacity; safer than Li-Co; commonly mixed with NMC to improve performance. | Provides high capacity power. Serves as Hybrid cell. Favorite chemistry for many uses; market share is increasing. | Very flat voltage discharge curve but low capacity. One of the safest Li-ions. Used for special markets. Elevated selfdischarge. | Shares similaities with Li-Co. Serves as enerygy cell. | Long life, fast charge, wide temperature range but low specific energy and expensive. Among safest Li-ion cells. |
Typical specific energy of lead-, nickel-and lithium-based batteries
Li-aluminum (NCA) is the clear winner by storing more capacity than other systems, this only applies to specific energy. In terms of specific power and thermal stability, Li-manganese (LMO) and Li-phosphate (LFP) are superior. Li-titanate (LTO) may have low capacity but this chemistry outlives most other batteries in terms of life span and also has the best cold temperature performance. Moving towards the electric powertrain, safety and cycle life will gain dominance over capacity. (LCO stands for Li-cobalt, the original Li-ion.)
Structure of Lithium ion Batteries:
Reference: