Disassembly Investigation of Battery/Capacitor Cells
Gas Analysis (Analysis of Gas Generated in Batteries)
Gas analysis in the batteries generated by initial charge/discharge, overcharge and over discharge, and after long time use is an important analytical tool to investigate deterioration or failure of the battery.
JFE-TEC analyzes gas component generated in the battery by applying gas chromatography mass spectrometry (GC-MS) and other techniques.
We also provide in-situ measurement services.
| Environment | Reaction | Reaction mechanism |
|---|---|---|
| High dew point | Water and Li | Li + H2O → LiOH + H2 |
| Water and solvent | ROCO2R+H2O → 2ROH+CO2 | |
| Overcharge | Oxidative decomposition of solvent | ROCO2R + 3O2 → 3CO2 + 3H2O |
| Over discharge | Reduction of solvent | ROCO2R + e- + Li+ + 1/2H2 → ROCO2Li + R |
Example of Investigation of Cause of Swelling of Mobile Phone Lithium Ion Battery Immediately after Start of Use
-
Appearance of swollen battery -
Sampling of gas
in battery → Gas analysis
(GC, GC-MS) -
- Total amount of gas in the swollen cell was about 6 times that in a good new cell, and most of the gas was hydrogen.
Contamination of cell by water and/or overcharging was presumed to be the cause of swollenness of cell.
