failure modes  /  lithium battery failures
battery & electrochemistry · forensic engineering

Lithium-ion battery failure analysis.

When a cell vents, ignites, or fails in the field, the cause can decide a recall, a lawsuit, or a plant's future. We find it — independently, and on the evidence.

A lithium-ion failure is rarely random. By the time a cell reaches thermal runaway, a chain of events has already played out — and that chain leaves physical evidence. Our work is to read it: what initiated the failure, whether it was a defect, a misuse, or a design margin, and what that means for the people now asking who is responsible.

mechanisms

How lithium-ion cells fail.

Most catastrophic failures end the same way — thermal runaway — but they start in very different places. Identifying the initiating mechanism is the whole question.

Thermal runaway

A self-sustaining exothermic reaction once a cell passes its onset temperature — the common end-state, not the root cause.

Internal short circuit

Lithium dendrites, electrode burrs, or debris bridging the separator and discharging energy locally.

Separator defects

Thinning, pinholes, contamination, or shutdown-layer failure that lets anode and cathode meet.

Manufacturing contamination

Metallic particles, moisture, or coating defects introduced in cell production driving latent shorts.

Overcharge / over-discharge

BMS, charger, or balancing faults pushing cells outside their safe voltage window.

Mechanical & thermal abuse

Crush, puncture, vibration, or external heat — including adjacent-cell propagation in a pack.

methodology

What the evidence shows — and what we examine.

The conclusion comes from the cell, the pack, and the data around them — not from a description. A typical examination draws on:

Non-destructive imagingCT and X-ray to locate the initiation site and internal damage before any teardown.
SEM / EDS microscopyImaging and elemental analysis of electrodes, separator, and any contaminant particles.
Thermal & calorimetryDSC/ARC to characterize onset temperatures and runaway energetics.
BMS & charge-history dataVoltage, current, and temperature logs reconstructing the conditions before failure.
Controlled teardownDocumented disassembly preserving chain of custody and the failure's spatial story.
Materials & chemistryElectrolyte, coating, and electrode composition against the design specification.
what's at stake

One cell, very large consequences.

A single battery failure can put any of these in motion at once:

product recall product-liability litigation warehouse / plant fire personal injury transport (UN 38.3) exposure insurance subrogation

Preserve the evidence first.

Do not discard, charge, clean, or disassemble a failed cell — it can destroy the proof and the case. Our free checklist walks first responders and counsel through it.

common questions

Lithium battery failure — the questions we hear.

What causes a lithium-ion battery to catch fire?

Almost all fires end in thermal runaway, but the trigger varies — an internal short, separator breakdown, overcharge, external heat, or mechanical damage. Which one applies to a specific failure is exactly what a forensic examination determines.

Can you tell why a specific battery failed?

Yes — through imaging, teardown, microscopy, materials analysis, and the cell's charge history. The answer is built from that evidence, which is also what makes it defensible.

What should I do with a failed battery before an analysis?

Don't discard, disassemble, charge, or clean it. Store it safely away from heat and moisture, document its condition, and preserve the chain of custody. Altering it can amount to spoliation.

related

Related failure modes & collections.

A battery failed. Find out why.

Tell us what happened. We'll triage it and connect you with the right expert — usually within one business day.

failure-analysis assistanttriage · not a substitute for an expert
Tell me what failed and I'll help scope it — the likely mechanisms, what's at stake, and which expert fits. I won't give the formal analysis here.