
Engineers once designed our cars to brace for impact. Progress was measured in crash survival, so they built sturdier frames, added seatbelts, and improved airbags. These safety improvements were vital, but they were designed to minimise damage rather than prevent crashes from happening in the first place.
Technology today has come a long way, allowing the automotive industry to expand its approach. New features like lane-departure warnings, intelligent speed assistance, and blind spot sensors have moved safety features upstream. This advanced safety strategy has saved countless lives and reshaped how the entire car industry designs, tests, and markets its products.
It is time for energy storage to adopt a similar approach. In the past year alone, battery storage incidents have disrupted energy operations across multiple states. As the industry scales, so do the risks—and the need for a new safety paradigm. The sector has invested heavily in refining what happens if a battery system safety incident occurs. Sensors detect abnormal heat or off-gas. Containment limits the spread. These measures are critical, but they are designed to activate once damage is already underway. Even the fastest detection and mitigation systems may not intervene before serious damage to the battery storage system occurs. This is akin to relying on airbags without the benefits of a car’s collision avoidance technology: valuable, but purely reactive rather than preventive and proactive.
From reaction to prevention: A new safety paradigm
To make battery energy storage safer at scale, systems must be designed to intervene earlier—before conditions can become explosive. This means addressing the incidents at the source.
Battery storage safety incidents can be caused by an accumulation of flammable gases released during thermal runaway, where heat builds inside a battery cell faster than it can be dissipated. Inside a battery enclosure, these gases can mix with air and create an explosive environment. If an ignition source appears, the result can be a violent deflagration that could damage equipment, endanger personnel, and disrupt critical energy operations.
Proactive safety tools are designed to break that chain, like a car that is designed to brake automatically when sensors detect a collision risk. For instance, some battery safety tools use controlled ignition at low concentrations, igniting flammable gases before they reach hazardous levels. This allows the battery storage system to act before a dangerous condition becomes out of control.
Rigorous testing must be at the centre of battery storage safety
Recent full-scale tests in the United States have shown that a prevention-first approach can reliably prevent uncontrolled deflagrations and structural damage in real-world battery storage systems.
One example comes from Wärtsilä Energy Storage, we conducted a series of tests on our Active Ignition Mitigation System (AIMS). The system deliberately ignited flammable gases as they were released during simulated thermal runaway. Across all three tests, gas concentrations remained below hazardous thresholds, no uncontrolled deflagrations occurred, and the battery enclosure maintained its structural integrity.
These tests reflect a broader shift in safety philosophy. Rather than focusing solely on designing battery enclosures to withstand explosions, energy storage technologies need to prioritise making incidents as preventable as possible.
This proactive approach should also shape how the industry collaborates. Testing and safety design must involve customers, fire safety consultants, first responders, and other community partners. Testing under worst-case conditions builds trust, informs emergency protocols, and generates the data needed to guide smarter, prevention-focused safety standards.
The time for battery safety advancements is now
Battery energy storage is scaling fast, with new storage records expected again this year, according to BloombergNEF. The pace of these developments is made more complex by sites being developed larger and faster than ever before across all types of locations, from islanded grids to dense urban areas. Dangerous battery storage incidents can slow adoption, trigger costly delays, and erode trust in a technology that is at the centre of enabling the renewable energy transition.
One thing is clear: the future success of the battery storage industry will be measured not by how well it responds when things go wrong, but by how rarely things go wrong in the first place. The tools to achieve that future already exist–and they’re being tested, refined, and deployed today. But, to make proactive safety the norm rather than the exception, we need collective action.
Regulators must update standards to reward prevention-first designs. Developers should demand systems that actively prevent hazardous conditions, not just survive them. Procurement teams need to evaluate safety technologies based on their ability to intervene early. Engineering teams should treat proactive safety as a core design, not an optional feature. Fire safety experts and first responders must be involved from the start to ensure real-world readiness.
It is only in shifting our mindset from reaction to prevention that the industry can build safer, more resilient energy storage systems—protecting people, projects, and the progress of the clean energy transition.