Early detection before thermal escalation
Continuously monitors electrolyte vapour, hydrogen, ambient conditions and cell temperature — combining their behaviour into one early-warning decision during the critical window before thermal escalation.
01 The warning window
A failing cell does not jump from normal to burning instantly. Earlier stages are the ones worth acting on.
Cell operating within its designed envelope.
Internal reactions begin. Nothing visible, nothing hot.
Electrolyte vapour and hydrogen appear in the enclosure.
Cell temperature begins to rise — now measurable at the surface.
Self-heating becomes self-sustaining and uncontrollable.
The warning window has closed.
See the warning. Before you see the fire.
02 See the signal before the heat
In a controlled venting event, chemical channels respond while the cell surface is still behaving normally. The sensor acts on that lead time.
Normalised trace — relative sensor response over time
The alert asserts while VOC and hydrogen are already climbing and surface temperature has barely moved — the window where intervention is still possible. Timing varies with cell chemistry, enclosure volume and sensor placement.
03 Four channels, one picture
Each sensor answers a different question. Together they distinguish a genuine battery event from a passing change in the environment.
Chemical — Broad Spectrum
Metal-oxide air-quality sensor
Tracks volatile organic compounds and nitrogen oxides — the broad chemical fingerprint released when a cell begins to vent electrolyte. Raw signals are temperature- and humidity-compensated in real time.
Chemical — Targeted
MOS hydrogen sensor with heated element
A dedicated hydrogen channel, because H₂ is one of the most characteristic early off-gas products of a failing lithium cell. Its reading is normalised against ambient conditions for a stable, concentration-based output.
Reference — Ambient
Digital ambient climate sensor
Provides the compensation reference that keeps the chemical channels honest, and independently flags rapid environmental shifts that could otherwise look like an event.
Thermal — Direct Contact
High-accuracy NTC, 12-bit acquisition
Mounted against the cell or pack surface, this channel measures the actual thermal state of the battery — the confirmation that a chemical signal has a physical counterpart.
04 From raw signals to a decision
Firmware runs a continuous, multi-stage evaluation. It is deliberately conservative: better to stay silent than to cry wolf.
On power-up the module learns the ambient chemical and thermal environment it is installed in, so it can judge what “normal” looks like on site.
Chemical concentrations and temperature are monitored as trends over time — magnitude, direction and rate of change all carry meaning.
A chemical shift accompanied by a hydrogen rise and a thermal change is treated very differently from a chemical shift alone.
Evidence must persist before the alert line is asserted. Once asserted, it is held and only released after conditions have genuinely cleared.
Doors opening, HVAC swings and humidity spikes are recognised and discounted.
A dropped channel reports a fault — never a false “all clear”.
Sensors re-initialise on failure and the model re-baselines automatically.
05 Why multi-sensor detection
By the time temperature rises significantly, failure may already be underway. Chemical and thermal signatures together identify abnormal behaviour earlier.
Chemistry can move before temperature.
Traditional protection
You are told the battery is already hot. The event is in progress.
Battery Safety Sensor
You are told something abnormal may already be happening — before temperature becomes the dominant signal.
06 Keep your NTC. Add another layer.
Not a replacement for thermal protection you already have. It sits alongside it — adding chemical and hydrogen context to the decision.
Your existing protection
Battery Safety Sensor — additional layer
Drives a MOSFET, relay, buzzer or host interrupt. No protocol stack required.
07 Technical specifications
A self-contained module — sensing, processing and alert output on one small board.
| Parameter | Value |
|---|---|
| Gas sensing — broad spectrum | VOC and NOx raw signal channels |
| Gas sensing — hydrogen | MOS hydrogen channel, analogue output |
| Ambient climate | Digital temperature and relative humidity |
| Thermal channel | External NTC thermistor input, 12-bit acquisition |
| Alert output | Single digital line, active HIGH, MOSFET-gate capable |
| Sensor bus | I²C, 400 kHz |
| Sensor supply | Separate heater rail for MOS gas elements |
| Debug interface | UART serial telemetry |
| Firmware | Watchdog-supervised state machine, automatic sensor recovery |
| Operation | Continuous, unattended monitoring |
| Form factor | Compact single-board module |
Specifications are indicative and subject to change. Sensor warm-up periods apply after power-up.
08 Applications
Anywhere lithium cells are enclosed, unattended, or hard to reach.
09 Get started
Tell us about your pack and we will show where Battery Safety Sensor fits into your architecture. Samples and integration support are available.
