New sensor addresses rare, but potentially fatal, thermal runaway in EVs

Honeywell partners with Nexceris to address the use of lithium-ion (Li-ion) batteries in vehicles and the potential danger with the thermal runaway these vehicles emit.

Here, Electronic Specifier talks to Sarah Martin, President of Honeywell Sensing and Safety Technologies, about safety critical considerations for electric vehicle manufacturing.

Why did you choose to partner with Nexceris?

As the world transitions to electric powered vehicles, automakers need to provide lithium-ion batteries that function properly and safely during all stages of their lifecycle.

At Honeywell, we are helping our customers mitigate safety risks as they grow their electric vehicle (EV) portfolios with ready-now solutions. We are expanding our strategic alliance with Nexceris to create an enhanced suite of battery sensors that will help automotive manufacturers strengthen their battery health monitoring systems with the ability to detect thermal runaway conditions even earlier.

Can you explain what thermal runaway is?

Thermal runaway is one of the main safety risks associated with the use of lithium-ion batteries. It is a phenomenon that causes extremely high temperatures within the battery cell where it no longer functions properly and may eventually lead to vehicle failure, smoke and fire. It can be caused by a variety of factors, including internal defects, an external short circuit or over-charging.   

How great is the risk of thermal runaway causing a fire?

Use of lithium-ion batteries pose rare but significant safety risks from thermal runaway. If thermal runaway is not properly managed and addressed, it impacts the overall drivability and safety of EVs. EV batteries can go into thermal runaway while the vehicle is being operated or when a car is parked and unattended, which is why proper battery safety sensing technology is critical. Without it, the vehicle becomes at risk for fire hazards.

What is the sensor-based solution you have created?

We are collaborating with Nexceris to develop an enhanced suite of battery monitoring sensors. Our sensor-based, advanced gas detection solutions in EV battery packs allow for early intervention, helping avoid costly property damage and safety issues. We have a proprietary solution that can detect conditions that lead to thermal runaway and help solve safety challenges.  

I understand there are four steps that indicate a battery failure, how early can the sensor detect safety issues?

Fires from lithium-ion batteries are dangerous and difficult to contain after they begin, which is why detecting thermal runaway sooner is critical. Battery safety sensing can be challenging because not all lithium-ion batteries are manufactured the same. Across manufacturers, lithium-ion batteries can be made using various chemistries and formulas, which means different concentrations of gases may be released prior to thermal runaway (known as off-gassing). Our advanced sensing solution can detect those harmful gases at early stages.

How great is the current need for a thermal runaway solution in EVs?

Global sales of EVs doubled in 2021 from the previous year, and 2022 data shows that year over year sales of EVs continues to climb. Protecting against thermal runaway in electric vehicle batteries is crucial to helping keep people safe. Through this sensing technology, we are offering our vehicle manufacturing customers a more advanced safety solution to help protect drivers on the road, homeowners who may have EVs parked in their garages and shipping handlers transporting EVs to their final destinations.