What raw materials are used to make lithium ion batteries? How are the raw materials used in the batteries processed? What chemical equations take place in the battery?
http://en.wikipedia.org/wiki/Lithium-ion_battery
To make lithium-ion batteries, several raw materials are used. The main components include lithium, graphite, cobalt, nickel, and various other metals and chemicals. Let me explain the process and chemical equations involved in making lithium-ion batteries:
1. Lithium Extraction: Lithium is typically extracted from lithium-containing ores or brine deposits. The ores go through processes like mining, crushing, and roasting, while brine deposits are pumped to evaporation ponds. After purification and concentration, lithium carbonate or lithium hydroxide is obtained.
2. Metal Extraction: Cobalt and nickel are often mined as byproducts of copper or nickel mining. After extraction, these metals undergo purification processes to remove impurities and obtain high-quality cobalt and nickel compounds.
3. Electrode Preparation:
a. Anode (Negative Terminal): The anode is made from graphite, which is coated onto a copper foil. This involves mixing ultrafine graphite particles with a binder and then applying the mixture onto the foil.
b. Cathode (Positive Terminal): The cathode usually consists of lithium cobalt oxide (LiCoO2), lithium iron phosphate (LiFePO4), or another lithium metal oxide. The metal oxide is mixed with a conductive additive and binder, then coated onto an aluminum foil.
4. Separators: A separator is a porous material placed between the anode and cathode to prevent electrical short circuits. The separator allows the flow of lithium ions while blocking the movement of electrons.
5. Electrolyte: The electrolyte is typically a combination of lithium salts, such as lithium hexafluorophosphate (LiPF6), and organic solvents. This electrolyte allows the movement of lithium ions between the anode and cathode.
6. Cell Assembly: The anode, cathode, separator, and electrolyte are assembled together in a specific order to form a battery cell. They are then sealed in a casing to prevent leakage.
Chemical equations in a lithium-ion battery involve the movement of lithium ions and electrons during charging and discharging:
- Discharge (power delivery):
Anode: LiCoO2 ↔ Li1-xCoO2 + xLi+ + xe-
Cathode: C + xLi+ + xe- ↔ LixC
- Charge (recharging):
Anode: Li1-xCoO2 + xLi+ + xe- ↔ LiCoO2
Cathode: LixC ↔ C + xLi+ + xe-
These equations demonstrate the reversible flow of lithium ions between the anode and cathode during the battery's operation.
It is important to note that the specific materials and chemical equations can vary depending on the battery chemistry and manufacturer, but this explanation covers the general process of making lithium-ion batteries.