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
Ans:- We know that, there are 6 types of lithium ion batteries are available such as:-
- LCO (Lithium Cadmium Oxide)
- LMO (Lithium Manganese Oxide)
- LFP (Lithium Iron Phosphate)
- NMC (Lithium Nickel Manganese Cobalt Oxide)
- NCA (Lithium Nickel Cobalt Alluminium Oxide)
- LTO (Lithium Titanate Oxide)
| No. | Types of Lithium ion Batteries | Anode | Cathode | Separator | Electrolyte |
During Charging Period Chemical reactions at Cathode & Anode |
During Discharging Period Chemical reactions at Anode & Cathode |
During Charging period Overall reactions inside the cells |
During Discharging Period Overall Reaction Inside the cell |
| 1. | LCO | Graphite (C6) | LiCoO2 | polyolefin |
Lithium salt(Lithium hexafluorophosphate) in an organic carbonate solution such as ethelyne carbonate,dimethyle carbonate,propelyne carbonate etc. |
Cathode:-LiCoO2 → (Li+) + (e-) +(CoO2) Anode:- (Li+) + C6 + (e-)→ LiC6 |
Anode:- LiC6 → (Li+) + C6 +(e-) Cathode:- (Li+) + (e-) + (CoO2) → LiCoO2 |
LiCoO2+C6→ LiC6+CoO2 | LiC6+CoO2→LiCoO2+C6 |
| 2. | LMO | Graphite (C6) | LiMn2O4 | polyolefin | LiPF6 with organic carbonate solution. |
Cathode:-LiMn2O4 →(Li+) + (e-)+Mn2O4 Anode:-(Li+) + (e-)+ C6 →LiC6 |
Anode:- LiC6 → (Li+) + C6 +(e-) Cathode:- (Li+) + (e-) + Mn2O4 → LiMn2O4 |
LiMn2O4+C6→LiC6+Mn2O4 | LiC6+Mn2O4→LiMn2O4+C6 |
| 3. | LFP | Graphite (C6) | LiFePO4 | polyolefin | LiPF6 with organic carbonate solution. |
Cathode:-LiFePO4 → (Li+) + (e-) + FePO4 Anode:- (Li+) + C6 + (e-)→ LiC6 |
Anode:-
LiC6 → (Li+) + C6 +(e-) Cathode:-(Li+)+(e-)+FePO4 →LiFePO4 |
LiFePO4+C6 →LiC6+FePO4 | LiC6+FePO4→LiFePO4+C6 |
| 4. | NMC | Graphite (C6) | LiNiMnCoO2 | polyolefin | LiPF6 with organic carbonate solution. |
Cathode:-LiNiMnCoO2 → (Li+) + (e-)+NiMnCoO2 Anode:- (Li+) + (e-)+ C6 →LiC6 |
Anode:- LiC6 → (Li+) + C6 +(e-) Cathode:-(Li+) + (e-) + NiMnCoO2 → LiNiMnCoO2 |
LiNiMnCoO2+C6→LiC6+NiMnCoO2 | LiC6+NiMnCoO2→ LiNiMnCoO2+C6 |
| 5. | NCA | Graphite (C6) | LiNiCoAlO2 | polyolefin | LiPF6 with organic carbonate solution. |
Cathode:-LiNiCoAlO2 → (Li+) + (e-)+NiCoAlO2 Anode:- (Li+) + C6 + (e-)→ LiC6 |
Anode:- LiC6 → (Li+) + C6 +(e-) Cathode:-(Li+) + (e-) + NiCoAlO2→LiNiCoAlO2 |
LiNiCoAlO2+C6→LiC6+NiCoAlO2 | LiC6+NiCoAlO2→LiNiCoAlO2+C6 |
| 6. | LTO | Graphite (C6) | Li4Ti5O12 | polyolefin | LiPF6 with organic carbonate solution. |
Cathode:-Li4Ti5O12 → (4Li+) + (4e-) + Ti5O12 Anode:- (Li+) + (e-)+ C6 →LiC6 |
Anode:- 4LiC6 → (4Li+) + 4C6+(4e-) Cathode:- (4Li+) + (4e-) + Ti5O12 → Li4Ti5O12 |
Li4Ti5O12+C6→LiC6+Ti5O12 | 4LiC6+Ti5O12 → Li4Ti5O12+4C6 |
As we know, the anode of Lithium ion battery is made up with graphite(C6) & the cathode is made up with Lithium metal oxide(LiMO2)
During charging period of a lithium ion cell,
- 1st the cathode is energised so that Lithium metal oxide breaks down as follows
LiMO2 → (Li+)+(e-)+MO2
- then this lithium ion moves through the electrolyte & react with the anode to form Lithiate carbon.
(Li+)+(e-)+C6→LiC6
- then the overall reaction during charging period will be
LiMO2+C6→LiC6+MO2
During discharging period,
- 1st the anode is energised & Lithiate carbon breaks into following components
LiC6→(Li+)+(e-)+C6
- this lithium ion moves towards the cathode to react with metal oxide forming Lithium metal oxide again
(Li+)+(e-)+MO2→LiMO2
- then the overall reactions for discharging period will be
LiC6+MO2→LiMO2+C6
that is the overall reaction for both charging & discharging period of a Lithium ion cell.
2.Compare the differences between each type of Li+ion batteries based on their characteristics
Ans:-
| No | Name of Li-ion Battery | Full name with symbol |
Characterstics Advantages |
Characterstics Disadvantages |
Uses |
| 1. | LCO | Lithium Cobalt Oxide (LiCoO2) |
i. High energy density that means it can store large amount of enery or power in unit volume. ii. Long runtime period |
i.Low discharge current. ii. safety feature is also low. iii. Internal resistance increase with cycling & aging. |
LCO baterries are mainly usedin portable electronocis devices such as smartphones,laptop,tablets etc. these are also used in smaller EVs. |
| 2. | LMO | Lithium Manganese Oxide (LiMn2O4) |
i.Charging time is very less i.e:- it charges quickly. ii. high specific power i.e:-it can deliver higher current than LCO battery.. iii. Better thermal stabilty i.e:- it can be operate higher temprature than LCO battery. iv. safety is more. |
i.Lower capacity than LCO battery. |
LMO batteries are used in medical devices & equipment,power tools,Electric bike & some cases they are used for laptops & electric cars. |
| 3. | LFP | Lithium Iron Phosphate (LiFePO4) |
i.less heating in nature. ii.Better power density i.e:- high specific power iii.long life iv. safety is more here also. |
i. lower energy density |
These are used in cars,bicycles,solar devices etc. |
| 4. | NMC | Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2) |
i.Longer life cycle ii.lower cost. iii.high power density also iv. more safety to use |
i.Slightly lower voltage than LCO battery. |
These are used in power tools,electric bikes, & other electronic powertrains. |
| 5. | NCA | Lithium Nickel Cobalt Alluminium Oxide (LiNiCoAlO2) |
i.High energy density. ii.Longer life span iii. good specific power |
i.Less safety ii.High cost comparision to other Li-ion batteries. |
NCA batteries are used in Power grid applications,medical devices & electric cars. |
| 6. | LTO | Lithium Titanate Oxide (Li4Ti5O12) |
i.Excellent low temprature discharge characterstics ii.Charge capability is very high iii. wide temprature range i.e:- it can be operatable at wide range of temprature. iv.Safety is very high. |
i. High cost ii. lower energy density |
They are used in different applications such as solar powered street lights, UPS,fast charge stations,electrical powertrains etc. |