IEC 62133: A Passport to the World of Safe Batteries. Everything you need to know about certification

We are living in the "cordless" era. From smartphones, laptops, and wireless headphones to modern medical devices and power tools, the contemporary world is powered by chemical energy encased in small metal cans or polymer pouches. The drive toward miniaturization while simultaneously increasing capacity has effectively turned today's lithium-ion cells into small energy bombs. In this context, safety ceases to be merely a technical parameter and becomes the foundation of trust in the technology. This is where the IEC 62133 standard enters the scene.

What is IEC 62133?

IEC 62133 is an international standard developed by the International Electrotechnical Commission (IEC). It is the key global document defining the requirements and tests for the safe operation of portable, sealed secondary cells and batteries (i.e., rechargeable batteries).

In simpler terms, it is a "driver's license" for batteries. This document does not address how long a battery will run (that is the domain of performance and IEC 61960); rather, it determines whether it is safe for the end user both during normal operation and in emergency situations (known as foreseeable misuse).

For a battery manufacturer or importer, this standard is fundamental. Without an IEC 62133 compliance report, introducing a device to the European Union market carries enormous legal risk and is often physically impossible due to customs blocks.

Why is IEC 62133 now two different standards?

If you look at older test reports from before 2017, you will simply see the label "IEC 62133:2012". However, the battery world evolved too rapidly for a single document to encompass such vastly different technologies as stable nickel and explosive lithium. In February 2017, the standard was split into two independent parts:

IEC 62133-1: Nickel Systems This applies to cells and batteries based on nickel, primarily Ni-MH (Nickel-Metal Hydride) as well as older Ni-Cd types. Although this technology seems "retro," it remains crucial in simple power tools, emergency lighting systems, and older-generation medical equipment.

IEC 62133-2: Lithium Systems (Key for modern electronics) This applies to lithium cells and batteries in all forms: Li-Ion (cylindrical 18650, 21700) and Li-Pol (flat polymer cells). This is the part of the standard that concerns 99% of the consumer electronics market (smartphones, laptops, power banks).

Why is this important? Lithium is a highly reactive metal. Lithium-ion batteries have a much higher energy density and, in the event of a failure, are prone to thermal runaway. Part 2 (-2) of the standard introduced much stricter requirements tailored to the specifics of lithium, including a new approach to internal short-circuit testing.

In international trade, the old standard from 2012 has been withdrawn. A certificate from years ago is useless for a new product being introduced to the market today. One must require a report compliant with IEC 62133-2:2017 along with amendment AMD1:2021.

Is the standard mandatory and when?

Many manufacturers ask themselves, "Do I have to do these tests?" The answer is: Although the application of standards is voluntary, in light of Regulation 2023/1542, they constitute the safest path to demonstrating compliance with the safety requirements necessary for CE marking.

The CB System (IECEE CB Scheme) – Your Passport

IEC 62133 is the foundation of the CB Scheme, an international system for the mutual recognition of test reports. A CB report issued in one country is recognized in over 50 others (e.g., Korea, Japan). This allows for avoiding costly duplication of tests when expanding into foreign markets.

Battery Regulation (EU) 2023/1542

Since 2024, a new law has been in force in the EU requiring standalone batteries to bear the CE marking. The IEC 62133 standard is crucial for demonstrating general product safety; however, the CE Declaration of Conformity under the new Regulation (EU) 2023/1542 primarily requires meeting sustainability requirements.

UN 38.3 vs. IEC 62133 – A Vital Distinction

• UN 38.3: Required for transport (air, sea, land). UN 38.3 is required for transport, but this report is often requested by laboratories before starting IEC 62133 tests.

• IEC 62133: Required for operational safety. Without it, goods will be detained by Customs or withdrawn from the market. You need both.

What do safety tests look like?

The test laboratory is a place where "the worst day in a battery's life" is simulated. The goal is to check what happens when everything goes wrong. Here are the key tests for lithium technology:

A. Electrical Tests (System failure simulation)

• Continuous charging: Simulation of leaving a phone on the charger for 7 days.

• External short circuit: Shorting the terminals with a low-resistance wire. The temperature rises rapidly, and safety mechanisms must cut off the current.

• Overcharge: Charging with a voltage higher than permissible (simulation of a faulty charger).

• Forced discharge: Simulation of deep discharge in a multi-cell pack, where one cell may reverse polarity.

B. Mechanical Tests (Accident simulation)

• Crush Test: Physically crushing the cell with a force of 13 kN (approx. 1.3 tons). This simulates pinching or a traffic accident. According to clause 7.3.5, the acceptance criterion is no fire and no explosion.

• Free Fall: Dropping onto concrete from a height of 1 meter.

C. Environmental Tests (Extreme temperatures)

• Thermal Abuse: "Baking" a charged cell at a temperature of 130°C. The internal separator begins to melt, but the cell must maintain stability and not catch fire.

Who needs certification? Mandatory industries

If your product falls into one of the following categories, an IEC 62133 report is a necessity:

• Consumer Electronics (IT/AV): Smartphones, laptops, tablets. Required by the end-device standard IEC 62368-1.

• Medical Devices: Insulin pumps, defibrillators. Absolutely required by the medical standard IEC 60601-1.

• Wearables: Smartwatches, TWS headphones. Due to skin contact and burn risks, they are under the scrutiny of surveillance authorities.

• Power Tools: Drills, grinders. Must withstand high currents and vibrations.

• Power Banks: Classified as portable batteries under Art. 3(1)(9) of the Regulation.

Tips for Designers

Here is how to pass the certification process painlessly without breaking the bank:

• The "Building Block" Principle (Cell vs. Pack): Using certified cells allows omitting cell-level tests, but the battery pack must still pass the full sequence of mechanical tests (7.3.8), short-circuit tests (7.3.2), and overcharge tests (7.3.6).

• Documentation is key: Prepare the Datasheet (with real parameters!) and the BMS schematic (detailing MOSFET/PTC protection).

• Labeling: The battery must bear specific markings.

• Watch out for the "Golden Sample": Do not send a handmade prototype for testing that differs from the mass-produced version. Changing a single component in serial production invalidates the certificate.

Your Insurance Policy

The IEC 62133 standard is not just a bureaucratic requirement. In the face of the growing number of battery-powered devices and increasingly restrictive regulations, such as the new EU Battery Regulation, it is a guarantee of safety.

For a manufacturer, holding the certificate means open doors to global markets, meeting the requirements of major distributors, and legal protection in the event of an accident. It is proof that you have exercised due diligence and that your product is safe for the user. If you plan to conquer the electronics market, IEC 62133 is the first step you must take.