Formation

Example

Use in Lemonergy

Place operations and quality checks in process order.

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

Learn it in Lesson 3 · Cell production →

Connected concepts

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

Aging (production)

Storing freshly formed cells for days to weeks, at room or elevated temperature, so the SEI stabilises and any cell with a latent short reveals itself through voltage drop. Not to be confused with aging as degradation over a cell’s life.

Cell finishing

The third phase of cell production: formation, degassing, aging and end-of-line testing. It is slow and ties up capital — cells sit for weeks — which is why shortening it is a major research goal.

Degassing

Removing the gas a cell releases during formation. A pouch cell’s extra gas pocket is opened in a dry atmosphere, emptied and sealed off; large prismatic cells often vent through their fill opening before final sealing.

First-cycle loss

The lithium consumed in forming the SEI on the first charge, which never returns to the positive electrode: about 5–10 % of capacity for graphite and far more for silicon. Pre-lithiation is the way to pay this debt in advance.

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

Technical references

1. Current and future lithium-ion battery manufacturing

   Yangtao Liu, Ruihan Zhang, Jun Wang, Yan Wang · iScience · 2021

   Technical reference · Electrode preparation, cell assembly, formation and manufacturing trade-offs.