Lithium difluorophosphate

Example

Use in Lemonergy

Connect transport with electronic isolation.

This is a reference concept. No executable Lemonergy block has been verified for this term.

Connected concepts

Related concepts from the knowledge graph. Connections show context, not cause and effect. Hover or focus a linked term for its definition.

Cathode–electrolyte interphase

The counterpart of the SEI on the positive electrode: a thin layer of electrolyte oxidation products on the oxide surface. It is thinner and less stable than the SEI, and its growth contributes to impedance rise, especially at high voltage.

Ethylene sulfate

A cyclic sulfate, 1,3,2-dioxathiolane 2,2-dioxide, added to electrolytes at about 1–2 %, often together with vinylene carbonate. It is reduced on the negative electrode during formation, leaving a sulfur-containing SEI, and keeps cell impedance lower than VC alone would. It is used in both lithium-ion and sodium-ion electrolytes.

Electrolyte additive

A compound added to the electrolyte at a few percent to improve one property — vinylene carbonate and fluoroethylene carbonate build a tougher SEI, others suppress gassing or overcharge. Additive packages are among a cell maker’s closest secrets.

Lithium hexafluorophosphate

The lithium salt in nearly every commercial electrolyte, chosen for conductivity, aluminium passivation and cost rather than stability: it decomposes above about 60 °C and reacts with water to form HF.

Lithium salt

The dissolved salt that supplies the mobile lithium ions in a liquid electrolyte, almost always lithium hexafluorophosphate, LiPF₆, at about one mole per litre. It reacts with traces of water to form hydrofluoric acid, which is why cells are filled in a dry room.

Solid–electrolyte interphase

A film of electrolyte reaction products on the negative-electrode particles — graphite, and also silicon or lithium metal. It protects the electrode from further reaction but grows slowly for the whole life of the cell, consuming cyclable lithium.

References & further reading

Further reading on this topic

These sources provide broader context; they are not presented as citations for every statement in this entry.

1. Electrolytes and Interphases in Li-Ion Batteries and Beyond

   Kang Xu · Chemical Reviews · 2014

   Topic background · Electrolyte salts, solvents, additives and electrode interphases.