Lithium Oxidation States
Lithium has one stable oxidation state (+1) in virtually all its compounds — explore the rules, examples, and redox context on this reference page.
Use the Lithium Oxidation States
Bonded to any anion or electronegative partner
Lithium loses its single 2s¹ valence electron to form Li⁺. This +1 state is observed in all ionic salts, hydroxides, hydrides, carbonates, and organolithium reagents. It is the overwhelmingly dominant state in chemistry.
Pure lithium metal — elemental form
Lithium metal has oxidation state 0 by the universal rule that any pure element has oxidation state zero. This is the state at the negative electrode (anode) of a lithium-metal battery before discharge.
Rules for Assigning Lithium's Oxidation State
Any pure element has an oxidation state of zero by definition. Lithium metal (Li) — whether as foil, ingot, or a battery anode — is always assigned oxidation state 0.
Lithium has only one valence electron (2s¹). Losing it to form Li⁺ is energetically favorable, and lithium cannot attain any higher positive state without removing core electrons. No stable Li²⁺ or Li³⁺ compounds exist under ordinary conditions.
After assigning +1 to lithium, confirm that all oxidation states in the formula sum to the overall charge (0 for neutral compounds, −1 for anions, etc.). If the sum is wrong, check the other element, not lithium.
In organolithium compounds (e.g., n-BuLi, methyllithium CH₃Li, phenyllithium C₆H₅Li), the C–Li bond is highly ionic in character. By convention lithium is +1 and the carbanion carbon fragment is assigned the corresponding negative formal charge.
In lithium-metal batteries, Li⁰ at the anode oxidizes to Li⁺ (+1) during discharge. In commercial lithium-ion batteries, lithium remains in the +1 state throughout intercalation (LiC₆ ↔ LiCoO₂), while transition metal host atoms undergo redox.
Lithium Compound Examples by Oxidation State
| Compound | Formula | Li Oxidation State | Class | Verification |
|---|---|---|---|---|
| Lithium chloride | LiCl | +1 | Ionic salt | (+1)+(−1)=0 ✓ |
| Lithium fluoride | LiF | +1 | Ionic salt | (+1)+(−1)=0 ✓ |
| Lithium bromide | LiBr | +1 | Ionic salt | (+1)+(−1)=0 ✓ |
| Lithium iodide | LiI | +1 | Ionic salt | (+1)+(−1)=0 ✓ |
| Lithium hydroxide | LiOH | +1 | Base | (+1)+(−2)+(+1)=0 ✓ |
| Lithium oxide | Li₂O | +1 | Metal oxide | 2(+1)+(−2)=0 ✓ |
| Lithium peroxide | Li₂O₂ | +1 | Metal peroxide | 2(+1)+2(−1)=0; O is −1 ✓ |
| Lithium superoxide | LiO₂ | +1 | Metal superoxide | (+1)+(−½ each O); O avg −½ ✓ |
| Lithium hydride | LiH | +1 | Metal hydride | (+1)+(−1)=0 ✓; H is −1 |
| Lithium carbonate | Li₂CO₃ | +1 | Carbonate salt | 2(+1)+(+4)+3(−2)=0 ✓ |
| Lithium nitrate | LiNO₃ | +1 | Nitrate salt | (+1)+(+5)+3(−2)=0 ✓ |
| Lithium sulfate | Li₂SO₄ | +1 | Sulfate salt | 2(+1)+(+6)+4(−2)=0 ✓ |
| Lithium phosphate | Li₃PO₄ | +1 | Phosphate salt | 3(+1)+(+5)+4(−2)=0 ✓ |
| Lithium aluminum hydride | LiAlH₄ | +1 | Complex hydride | (+1)+(+3)+4(−1)=0 ✓; H is −1 |
| n-Butyllithium | C₄H₉Li | +1 | Organolithium | Li +1; C₄H₉ is −1 fragment |
| Methyllithium | CH₃Li | +1 | Organolithium | Li +1; CH₃ is −1 fragment |
| Lithium metal | Li | 0 | Elemental | Pure element; 0 by definition |
| Lithium anode (Li-metal) | Li⁰ | 0 | Elemental | Before discharge; 0 → +1 |
Quick Compound Lookup
Type a compound name or formula to find lithium's oxidation state in our reference list.
Start typing to filter compounds.
Decision Guide: Which State Applies?
Is it pure lithium metal?
If the substance is elemental lithium — Li metal foil, ingot, wire, or the anode in a lithium-metal battery — the oxidation state is 0. No further analysis needed.
Is lithium part of any compound?
In every compound — ionic salts, metal oxides, hydrides, hydroxides, carbonates, or organolithium reagents — lithium is +1. This is the only stable oxidation state lithium adopts in compounds.
Lithium as a Reducing Agent
Lithium metal (oxidation state 0) is one of the strongest reducing agents in chemistry. When it reacts and becomes Li⁺ (+1), it is oxidized — it loses an electron. Li therefore acts as the reducing agent.
(oxidation: 0 → +1, E° = −3.04 V)
Examples: Li reacting with water, halogens, oxygen, and nitrogen; Li anode during battery discharge.
Lithium in Battery Electrochemistry
In lithium-metal batteries, Li⁰ (0) at the anode oxidizes to Li⁺ (+1) during discharge. In commercial lithium-ion batteries, lithium remains in the +1 oxidation state throughout intercalation; redox occurs on the host materials (e.g., cobalt in LiCoO₂ or carbon in LiC₆).
Li-ion intercalation: Li⁺ remains +1 (host redox)
(Reduction of Li⁺ to Li⁰ in Li-ion cells is plating, an abnormal hazard)
The standard reduction potential of Li⁺/Li is −3.04 V — the most negative of all metals, making lithium exceptionally reactive.
Summary
Lithium (Li, atomic number 3) has only one stable oxidation state in chemistry: +1. As the lightest alkali metal, lithium readily loses its single valence electron to form the Li⁺ cation, and this +1 state is observed in all of its common ionic and covalent compounds — from lithium chloride (LiCl) and lithium hydroxide (LiOH) to lithium hydride (LiH) and lithium carbonate (Li₂CO₃). The only exception is elemental lithium metal (Li⁰) and organolithium species where formal oxidation states are assigned as 0 or +1 depending on convention. Understanding lithium oxidation states is essential for battery chemistry, inorganic synthesis, and balancing redox equations.
How it works
- Identify whether lithium is in elemental form (Li metal) or in a compound.
- If elemental, the oxidation state is 0 by definition.
- If lithium is in a compound, assign +1 — its only stable ionic state.
- Verify by checking that all oxidation states in the formula sum to the overall charge.
- Browse the compound table below to confirm the assignment for common substances.
- Use the quick lookup to filter compounds by name or formula.
Use cases
- Assign oxidation numbers in redox reactions involving lithium.
- Balance half-reactions in lithium and lithium-ion battery electrochemistry.
- Identify whether lithium is oxidized or reduced in a given reaction.
- Support AP Chemistry or university-level inorganic chemistry coursework.
- Verify oxidation state assignments for lithium salts and organolithium reagents.
- Teach the alkali metal oxidation state rule with concrete compound examples.
- Analyze lithium redox couples in solid-state and solution chemistry.
- Cross-reference lithium compounds for synthesis and reactivity predictions.