Electric vehicle (EV) adoption is scaling fast, and with it, the complexity of the batteries powering these platforms. Higher energy densities, faster charging, and evolving pack architectures introduce new safety challenges that go beyond traditional containment strategies.
Ajibola Fowowe, Director, Honeywell Sensing Solutions
Today, battery safety depends on integrated systems that can detect off-gassing, predict thermal events, and trigger rapid response in real time.
Ajibola Fowowe, Director, Honeywell Sensing Solutions, is advancing sensing strategies designed specifically for EV applications. Building on decades of work in mission-critical environments, Honeywell is applying that expertise to enable earlier fault detection, higher-fidelity data, and seamless integration into modern battery platforms.
In this Q&A, Fowowe discusses how sensors are reshaping the safety baseline in EV battery engineering, from early vent-phase detection to predictive, system-level intelligence.
Here’s what he has to say…
How can new sensing technology help engineers better monitor and manage an EV battery’s thermal conditions?
Ajibola Fowowe (AF): New battery monitoring sensor technologies are transforming how engineers address thermal runaway at the system level. Sensors can now detect early vent-phase signatures before the temperature escalates to a catastrophic point.
By spotting these early indicators, there’s a critical opportunity to act before a thermal runaway event. That time margin is critical: it allows the battery management system to isolate cells, reduce current, or trigger vehicle alerts before propagation occurs. This proactive model targets root-cause risks rather than symptoms, representing a significant step forward in designing safer and more resilient EV battery systems.
How are sensors evolving to advance battery designs?
AF: Sensors have shifted from peripheral safeguards to core battery design elements. As energy density climbs, reliable operation depends on multi-modal data streams, including temperature, voltage, impedance drift, and gas concentration.
Integrating those signals enables predictive safety functions: adaptive thermal regulation, fast-charging without lithium plating, and earlier detection of imbalance. In modern battery packs, sensors aren’t optional; they’re the foundation for safe performance at scale.
EV platforms must rely on high-quality pressure, temperature, and current sensors across the battery pack and powertrain for early fault detection and improved diagnostics.
How are safety standards keeping pace with battery innovations?
AF: Global standards, such as FMVSS 305a in the United States and GB 38031 in China, now require earlier fault detection and thermal containment. But real-world battery designs are moving faster. Advanced sensing already allows engineers to exceed minimum thresholds.
For safety-critical systems, “passing the test” is just the first step. Designing for beyond-compliance reliability is what prevents or ensure containment of field failures.
What can engineers expect when it comes to emerging EV sensing technologies?
AF: Artificial intelligence (AI)-driven predictive sensing is reshaping battery safety by enabling sensors to not only report faults but also anticipate them. Engineers should watch advances, such as fiber-optic thermal mapping, which provide high-resolution visibility across cells.
As new chemistries like solid-state become more common, sensing strategies must evolve to track micro-structural stresses traditional sensors could not detect.
How should engineers approach sensor placement inside a battery pack?
AF: Sensor placement is now a strategic design choice. Positioning along thermal gradients, busbars, and vent paths can mean the difference between early warning and missed detection. Distributed sensing across modules and subcomponents gives a clearer picture of battery health while minimizing blind spots and boosting diagnostic accuracy.
As a result, engineers must balance coverage with simplicity, optimizing placement without overcomplicating pack architecture.
As EVs shift toward 800-V platforms and faster charging capabilities, how are sensing strategies adapting?
AF: The move to ultra-fast charging introduces unique stressors, such as rapid thermal transients, lithium plating and insulation breakdown. Sensing strategies are adapting with higher sample rates, expanded thermal coverage, and gas detection during transient states.
These improvements enable battery safety sensors to maintain performance and safety in high-voltage conditions, ensuring that faster charging doesn’t come at the expense of reliability.
Honeywell’s BES LITE battery safety sensor, using proprietary gas sensing technology, selectively detects battery electrolyte vapor, an indicator of thermal events.
What are the most overlooked failure modes in battery design?
AF: Failure modes like slow-developing internal shorts, moisture ingress, or calendar aging often go undetected until late in the battery lifecycle.
Advanced sensing can monitor impedance drift, pressure buildup, and off-gassing to surface these silent risks early. This gives engineers visibility into degradation pathways that would otherwise remain hidden, allowing intervention before they escalate into catastrophic failures.
Outside of EVs, where else are these sensing challenges showing up?
AF: The same safety challenges extend to grid-scale storage and aviation. In large stationary solar arrays with battery energy storage systems early gas detection prevents cascading thermal events across hundreds of modules.
In aviation, battery safety technologies are increasingly coming into play with electric aircraft or urban air mobility (UAM) vehicles. For these uses, sensors must account for weight and redundancy, making precise sensing critical to certification.
These examples show EV-driven sensing strategies are already influencing other high-stakes applications.
How have expectations changed in recent years around integrating battery safety sensors with the broader vehicle data ecosystem?
AF: What’s changing is the depth of integration. Pack-level sensors now feed real-time data into vehicle controls and cloud platforms, enabling immediate protective actions and long-term predictive insights.
How will “smart battery safety” likely evolve over the next five years?
AF: Looking ahead, many in the industry expect battery safety to become more predictive. Emerging approaches such as multi-domain sensor fusion and AI-driven diagnostics point to a future where batteries can detect issues earlier and support corrective responses automatically.
While still early, this trend suggests a shift from reactive safeguards toward embedded, system-level safety intelligence.
Sources
- Honeywell: Electrolyte Sensing Enabling Early Detection & Prevention of Thermal Runaway
- Infineon: Thermal Runaway Detection and Mitigation with BMS Solutions
- EV Engineering & Infrastructure: Sensor Technology Enables Early Detection of Thermal Runaway in EV Batteries
- Springer: Advancements, Challenges, and Future Trajectories in Advanced Battery Safety Detection
- AVNET: To Fight EV Fires, Focus is on Early Detection of Battery Cell Thermal Runaway
- NHTSA: Early Detection of EV Battery Failures
- Wired: The Auto Industry Finally Has a Plan to Stop Electric Vehicle Fires
Filed Under: Batteries, Featured Contributions, Q&As, Sensors