Lithium
Atomic Data
| Atomic Number | 3 |
| Symbol | Li |
| Atomic Weight | 6.941 u |
| Density (STP) | 0.534 g/cm³ |
| Melting Point | 180.54 °C (453.69 K) |
| Boiling Point | 1342 °C (1615 K) |
| Electronegativity | 0.98 (Pauling) |
| Electron Config. | 1s² 2s¹ |
| Oxidation States | +1 |
| Phase at STP | Solid |
| Category | Alkali metal |
| Period / Group | 2 / 1 |
| CAS Number | 7439-93-2 |
Electron Configuration
1s2 2s1
| Shell | n | Subshell | Electrons | Cumulative |
|---|---|---|---|---|
| K | 1 | 1s | 2 | 2 |
| L | 2 | 2s | 1 | 3 |
| Total | 3 | 3 | ||
Abundance & Occurrence
Lithium makes up about 20 parts per million of Earth's crust. It is found in pegmatite minerals such as spodumene and lepidolite, and in salt flat brines. Chile, Australia, and Argentina — the “Lithium Triangle” — hold the majority of global reserves.
World Lithium Reserves by Country
Lithium-Ion Battery Demand by Sector (2023)
Discovery & History
Safety & Handling
- Reacts with water: produces hydrogen gas and lithium hydroxide. Even contact with skin moisture can cause irritation. Keep away from water sources.
- Fire hazard: lithium fires cannot be extinguished with water — use dry sand or class-D fire extinguisher. Lithium-ion battery fires are difficult to suppress and can reignite.
- Store in mineral oil or kerosene to prevent reaction with air and moisture.
- Medication toxicity: lithium carbonate has a narrow therapeutic window. Overdose causes tremors, vomiting, impaired memory, and can be fatal. Blood levels must be monitored regularly.
- Wear gloves and eye protection when handling lithium metal. Avoid inhalation of dust or fumes.
Lithium in the Real World
Real-World Uses
- Rechargeable batteries — Lithium-ion batteries power electric vehicles, smartphones, laptops, and grid-scale energy storage. Lithium’s high electrochemical potential gives these batteries exceptional energy density.
- Psychiatric medication — Lithium carbonate is a first-line mood stabiliser for bipolar disorder, reducing the frequency and severity of manic and depressive episodes.
- Lightweight alloys — Added to aluminium and magnesium alloys to reduce weight in aircraft fuselages, bicycle frames, and high-speed train bodies.
- Lubricating grease — Lithium stearate is the most common thickener in general-purpose greases, used in automotive wheel bearings and industrial machinery since World War II.
- Air conditioning & drying — Lithium chloride is highly hygroscopic and is used in industrial drying systems and air-conditioning dehumidifiers.
- Ceramics & glass — Lithium carbonate lowers the melting point of glass and ceramics and improves thermal resistance in cookware and telescope mirrors.
Downloadable Resources
Free periodic table reference sheets for classrooms, study sessions, and laboratory use.
Frequently Asked Questions
Can lithium treat depression?
Lithium carbonate is an established mood-stabilising medication used primarily for bipolar disorder and, in some cases, treatment-resistant depression. It is not a cure, but helps regulate mood episodes under strict medical supervision. Blood lithium levels must be monitored regularly due to its narrow therapeutic window.
Why is lithium used in batteries?
Lithium is ideal for batteries because it is the lightest metal with the highest electrochemical potential of any element — it can store and release large amounts of energy per unit of weight. Lithium-ion batteries power electric vehicles, smartphones, and laptops because of this exceptional energy density.
Is the world running out of lithium?
Not imminently. Global recoverable reserves are estimated at around 22 million tonnes, led by Chile, Australia, and Argentina. The challenge is that refining capacity is struggling to keep pace with surging demand from electric vehicles. Improved recycling and new extraction technologies are expected to ease long-term supply constraints.
Who discovered lithium?
Johan August Arfwedson discovered lithium in 1817 while analysing the mineral petalite in Berzelius’s laboratory in Sweden. Berzelius named it ‘lithium’ from the Greek lithos (stone). William Thomas Brande first isolated the pure metal by electrolysis in 1821.
Why is lithium stored in oil?
Lithium reacts readily with oxygen and nitrogen in air, forming a dull grey oxide-nitride crust. It also reacts vigorously with water, producing flammable hydrogen gas. Submerging it in mineral oil or kerosene prevents these reactions and preserves the pure metal.