Failure Analysis

We have the equipment and expertise required to investigate and identify the root cause of Li-ion battery failures.

Failure Analysis generally involves three main steps:

  • non-destructive analysis of cells, including voltage, impedance and CT scanning
  • opening selected cells in a dry room with photo documentation
  • detailed examination of specific areas with optical and electron microscopes. This can include elemental analysis by EDS if required.

CT Scanning

CT Scanning is a non-destructive x-ray technique that allows us to generate virtual cross sections through any part of a cell. CT scanning is an essential tool for cell failure analysis because it records the configuration and exact location of cell components prior to destructive analysis/disassembly. It can tell us where to look and what to look for during cell disassembly. Without a CT record vital information is easily overlooked.


CT cross section of a typical 18650 cell

Opening of Cells

Opening of cells is done in a dry room. Lithiated graphite anodes deteriorate rapidly in moist air and can even burn spontaneously so a dry atmosphere environment is essential for careful examination of disassembled Li-ion cells.


Electrodes from an opened prismatic cell
Mottled Li plating is visible on graphite anode

Detailed Examination

SEM (Scanning Electron Microscopy) allows detailed examination of small features, including elemental analysis.



Example of a large impurity particle extracted from the cathode of a self-discharging cell.


EDS analysis of the outlined area shows it consists of iron with a few % Cr and Mn.


These are some typical methods but each investigation is unique. In complex situations additional testing or analytical techniques may be needed to understand the cause of failure.