QR code placement and durability: where the code sits and how it survives use

A QR code on a battery is a data carrier, not a decoration. Article 13(6) requires batteries to bear a QR code from 18 February 2027, and for EV, LMT and industrial batteries above 2 kWh that code must give access to the battery passport. Placement and durability decide whether that duty works in practice. A code placed where it is abraded in normal handling, covered by a housing, or destroyed by heat will fail at the moment a reader needs it most: during repair, during a second hand sale, or at end of life.

Placement is therefore a record decision, not a packaging afterthought, and durability is tested against the life of the battery, not against the day of manufacture.

Where should a QR code be placed?

Placement follows Article 13: on the battery where possible, and on packaging or in accompanying documentation where placement on the battery is not possible for a stated reason. On the battery, the code should be placed on a flat, accessible surface, away from edges that are handled, clamped or fastened, and away from areas that are covered when the battery is installed. The code should be placed so that it can be scanned without dismantling the battery or removing it from its normal installation where that is achievable, because a code that requires dismantling to scan will not be scanned in the situations where a quick identity check matters. Where a battery is incorporated into a product, placement rules for the product and the battery interact, and the record should state where the code appears so that a reader knows where to look. Placement that is technically compliant but practically inaccessible fails the purpose of the code, even when it meets the letter of the placement rule.

What size and contrast does a code need?

Size and contrast decide readability. A QR code needs a quiet zone, a clear area around the symbol with no printing, of at least four modules on every side under ISO/IEC 18004, the QR code standard. Module size must be large enough for the scanning distance and the scanner type, with phone scanning and industrial scanning imposing different requirements. Contrast must be high: dark modules on a light background, with no pattern, logo or colour effect that reduces contrast. Error correction level affects durability of reading: a higher error correction level allows more damage before the code becomes unreadable, at the cost of a denser symbol for the same data. The encoded data should be kept short, because a shorter payload produces a lower version symbol with larger modules at the same printed size, and larger modules are easier to read and more tolerant of damage. A long URL with tracking parameters produces a dense, fragile code. A short, stable identifier URL produces a robust code.

How is durability tested?

Durability is tested against the conditions the battery will meet: abrasion from handling and installation, exposure to heat, cold, humidity, chemicals, ultraviolet light and cleaning, and the effects of vibration. The test should use the actual substrate and printing method for the battery, not a paper proof, and should include scanning after each exposure with the scanner types that readers will use. A code printed on a label that peels, fades or delaminates in service is not durable, however clear it looked on the day of manufacture. Durability testing should also cover the label adhesive and the substrate: a label that stays legible but detaches from the battery is a failure, because the code is then separated from the battery it identifies. The test record should state the conditions, the scanner types, the pass standard and the date, so that a later failure can be compared with the original test.

What happens when placement changes after repair or repurposing?

Repair, repurposing and remanufacturing can change the housing, the label or the installation, and each change can affect the code. A housing replacement that covers the original code, a new label applied over the old code, or a repurposed battery installed in a way that hides the code all break the route to the record. The operation record should therefore check code visibility and readability after the operation, and should record the check. Where the original code is damaged or covered, a replacement carrier bearing the same identifier should be applied, with the replacement recorded. A replacement carrier bearing a new identifier, without linkage, splits the history. A code that is left damaged because the operation record does not check it becomes a silent failure, discovered only when a later reader cannot scan.

What does the placement checklist summarise?

What limits apply to placement claims?

Placement and durability claims describe the code as manufactured and tested. They do not guarantee that a code will survive misuse, fire, crushing or other damage beyond the tested conditions. A code that is unreadable after severe damage is not necessarily a placement failure. The record should state the tested conditions, so that a failure can be judged against them. This guide gives general educational information only and does not give legal advice for a particular battery, label or installation.