Safety & compliance in battery systems: What you need to know

Whether you're powering critical rail infrastructure, military equipment or industrial systems, one thing is true across the board: the battery at the heart of your application needs to be safe, compliant and fit for purpose. It sounds straightforward. In practice, it involves a web of regulations and best practices that can feel overwhelming if you don't know where to start.

At DMS technologies, we've been navigating this landscape for over 40 years. So let's break it down.

Why battery safety and compliance matter more than ever

The regulatory environment around batteries has changed significantly in recent years, and the pace of change isn't slowing down.

In the UK, the Batteries and Accumulators Regulations 2008 set the baseline for what can be placed on the market, covering substance restrictions, labelling and documentation requirements. Alongside this, updates to WEEE (Waste Electrical and Electronic Equipment) regulations in 2025 tightened the rules around safe recycling and reporting, meaning businesses now need to think not just about how a battery performs, but how it exits service responsibly.

Then there's the UK Product Regulation and Metrology Act, which became law in July 2025, significantly expanding the broader regulatory framework for product safety. In parallel, new statutory guidelines from the Office for Product Safety and Standards (OPSS) specifically address fire risks from lithium-ion batteries, requiring thermal runaway prevention mechanisms as standard.

If you're supplying into regulated markets like rail, defence or healthcare, the compliance bar is even higher. Network Rail approval, military specifications and sector-specific certifications all add layers of requirement that go well beyond general product safety standards.

The key standards you need to know

Standards form the backbone of battery compliance. In the UK and European markets, the most relevant include:

·        EN IEC 62485-1 covers general safety requirements for secondary batteries and battery installations. This is a foundational standard for anyone specifying or supplying stationary battery systems.

·        IEC 62485-2 goes further, focusing specifically on the safe operation of stationary secondary battery systems. It covers everything from ventilation and installation to maintenance and inspection protocols.

·        BS EN 62133-2 applies to portable sealed secondary cells and batteries containing lithium systems. If your application is mobile or portable, this is likely to apply.

·        BS EN IEC 62620 covers secondary lithium cells and batteries for industrial applications, which is increasingly relevant as lithium technology continues to expand across sectors that have historically relied on lead acid or nickel-based chemistries.

Compliance with harmonised standards like these provides a presumption of conformity with the relevant regulations. In other words, if your battery system meets the standard, it's assumed to meet the law. That presumption matters when you're going through procurement, tendering or audit processes.

What thermal runaway actually means (and why you should care)

Thermal runaway is a chain reaction within a battery cell where rising temperature causes further heat generation, which raises the temperature further, until the cell vents, catches fire or fails catastrophically. It's the mechanism behind most serious lithium battery incidents, from consumer product recalls to the waste fires that UK regulators have flagged as a growing concern.

The risk isn't limited to cheap or low-quality cells. Even high-performance batteries can experience thermal runaway if they're damaged, incorrectly charged, stored in unsuitable conditions or operating outside their design parameters.

This is why a Battery Management System (BMS) is essential in any serious application. A properly specified BMS monitors cell voltage, current and temperature in real time, and intervenes when parameters go outside safe limits. For applications in demanding environments, whether that's the heat of an industrial facility or the vibration of a rail vehicle, a BMS is an essential part of the infrastructure.

Compliance in practice is more than paperwork

It's tempting to treat compliance as a box-ticking exercise. Get the test report, file the documentation, move on. But the organisations that approach battery safety that way tend to find out the hard way that it's not enough.

Genuine compliance means:

·        Specifying the right chemistry for the application. Lead acid, nickel cadmium, nickel metal hydride and lithium all have different safety profiles, temperature tolerances and regulatory requirements. What works in a telecom cabinet won't necessarily be appropriate in a mobile military application.

·        Ensuring the charging architecture is compatible. A battery that's perfectly safe with the correct charger can become a hazard with the wrong one. Charging profile compatibility is a compliance consideration, not just a performance one

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·        Maintaining documentation throughout the product lifecycle. Test reports, conformity declarations, commissioning records and maintenance logs all form part of the compliance picture. In sectors like rail, these documents are subject to audit and need to be traceable over long timeframes.

·        Planning for end of life. The 2025 WEEE updates mean that end-of-life handling needs to be built into procurement decisions, not left as an afterthought. Approved waste carriers, separate collection and recycling facility requirements all apply.

The value of an experienced battery partner

One of the challenges with battery compliance is that no two applications are identical. The standards provide the framework, but applying them correctly requires real-world experience across a range of chemistries, environments and sectors.

That's where working with a knowledgeable battery partner makes a genuine difference. An experienced supplier can help you identify the right technology for your application, advise on BMS specification, ensure your documentation is audit-ready and flag potential issues before they become problems.

At DMS technologies, we work across some of the most demanding regulatory environments in the UK, including rail (where we hold Network Rail approval for a range of battery and charger systems), defence, oil and gas, and emergency services. We've built that knowledge over decades, and we put it to work for our customers at every stage of a project.

A final word on staying ahead

The regulatory landscape will continue to evolve. Lithium battery legislation in particular is tightening across both the UK and EU, and the direction of travel is clear: higher safety standards, greater traceability and stronger accountability for both manufacturers and operators.

The good news is that safety and performance aren't in opposition. A battery system that's properly specified, correctly installed and actively maintained will almost always outperform one that's been chosen on cost alone. Compliance, done properly, is just good engineering.

If you'd like to talk through your battery specification or compliance requirements, the team at DMS technologies is happy to help.