product-guide
What Do We Actually Print on the Battery? QR Codes, GS1 Digital Link, and Getting Identity Right
The battery passport's data carrier is a QR code resolving to a per-unit record. Here's how GS1 Digital Link identifiers map to model, batch, and item level — and the mistakes to avoid before printing.
The short answer
You print a QR code encoding a GS1 Digital Link URL — a web address built from your product's GTIN plus, for batteries, a serial number — and that URL resolves to the passport record for that exact unit. The code is a pointer, not a payload: the passport is the dataset behind the link, which is why it can be corrected and appended to for years without touching the label.
How the identifier grammar works
GS1 Digital Link expresses identity as a path, and the depth of the path sets the granularity:
| Path contains | Resolves to | Used for |
|---|---|---|
| GTIN only | Model-level record | First-wave textiles (one record per SKU) |
| GTIN + batch/lot | Batch-level record | Raw material passports |
| GTIN + serial | Item-level record | Batteries — required |
This grammar is the reason "get a QR code" is the wrong way to frame the task. Any QR generator can make a scannable square; the compliance question is whether the identifier inside it is structured so that this unit resolves to this unit's record — including years later, in a recycler's intake bay, when nobody scanning it knows or cares which vendor made the label.
Four mistakes to catch before anything gets printed
- SKU-level codes on serialized products. One shared QR per model is fine for a T-shirt and non-compliant for a battery. If every unit in a carton carries the same code, the passport can't be item-level.
- Dead-end short links. Marketing-style QR redirects with no identifier structure can't participate in the GS1 resolution ecosystem and tie your compliance to one vendor's URL shortener staying alive.
- Encoding data instead of identity. Stuffing chemistry or spec data into the QR itself freezes it at print time. The regulation's model assumes updatable records — carrier and content must stay separate.
- No GTIN discipline. Digital Link paths are built from GTINs. If variants share GTINs loosely or serials aren't unique within a GTIN, the identity layer wobbles before the passport layer even starts.
Durability is part of the requirement
A passport that must survive repair, resale, and recycling implies a carrier that survives them too — label material, placement, and marking method (print vs. laser vs. dot-peen) are compliance decisions, not just production ones. The identifier's whole value is being readable at end-of-life, the moment when the least careful people handle the product.
What this means for your team
Before the label conversation, settle the identity conversation: confirm every in-scope product has a proper GTIN, every unit gets a unique serial, and the two combine into a Digital Link URL that resolves. Get that right and the QR code itself is the easiest step in the entire passport program.