Retail has long pursued a deceptively simple ambition: know where every product is, what condition it is in, and what will happen to it next. Traditional RFID moved the industry significantly closer to that vision (greater visibility into products moving across supply chains, stores, and fulfillment networks) by making item-level identification scalable. But knowing where an item is has become only part of the challenge.
The next leap in retail intelligence is no longer about simply identifying products but about making products sense, communicate, and contribute data.
Something that can be now achieved using passive Bluetooth Low Energy (BLE), often positioned within the broader Ambient IoT category. Through battery-free sensing, ambient backscatter communications, and AI-driven analytics, passive BLE (battery less BLE) is opening new possibilities for retailers. And with initiatives like Walmart’s fresh food traceability and quality mandates, plus the collaboration between Avery Dennison and Wiliot, the technology is moving from innovation story to operational reality.
RFID Identified Products. Ambient IoT Gives Them a Voice
Retailers increasingly need to know:
• What condition products are in
• Whether temperature-sensitive goods stayed compliant
• How products move in real time
• When shrink, spoilage, or disruptions are likely before they happen
Traditional RFID solved a major retail problem: scalable identity. Products could be tagged, located, counted, and authenticated. But RFID alone generally cannot tell a retailer:
• If strawberries exceeded temperature thresholds in transit
• If vaccines were exposed to compliance risk
• If produce shelf life is deteriorating
• If a high-value item has been moved unexpectedly
Passive BLE adds sensing and communication on top of identification.
What is Passive BLE (Battery less BLE) and How it Works?
Unlike active BLE devices that rely on batteries and power-hungry radios to generate their own signals, passive BLE relies on ambient backscattering and energy harvesting.
Instead of continuously generating its own radio signal, a passive BLE tag operates using ambient energy and reflected communications.
Here’s how it works without having a battery to power it:
1. Harvesting Energy
Battery-less BLE devices capture energy from surrounding radio waves (Wi-Fi, cellular), or sometimes light or motion, to power internal microchips.
2. Reflecting Signals
Rather than transmitting conventionally, the tag changes antenna properties to absorb or reflect radio waves from readers or smartphones.
3. Data Modulation
By altering reflected signals, the device embeds information such as:
• Temperature readings
• Inventory identity
• Environmental conditions
• Motion or occupancy data
Standard BLE-enabled devices can then interpret that data. This architecture enables several major advantages:
• Battery-free operation
• Ultra-low-cost deployment
• Extreme miniaturization
• Long operational life
• Scalable item-level sensing
Why Walmart’s Fresh Food Mandate Raises the Stakes
Walmart has steadily pushed suppliers toward stronger traceability, compliance, and fresh food monitoring requirements. It reflects a broader retail reality: traceability alone is no longer enough because retailers increasingly want to prevent spoilage and not just investigate it. Passive BLE could support that shift.
Imagine fresh foods carrying battery-free tags that continuously report:
• Cold-chain temperature excursions
• Time outside compliance windows
• Product freshness risk signals
• Handling anomalies
• Real-time product conditions
This way, operations move from reactive traceability toward predictive freshness intelligence.
At Walmart scale, even modest gains could translate into:
• Lower food waste
• Better product quality
• More targeted recalls
• Stronger supplier accountability
• Improved customer trust
And because passive BLE avoids battery replacement, deploying across millions or eventually billions of products becomes more feasible.
Avery Dennison and Wiliot: Building Ambient Intelligence Into Products
The partnership between Avery Dennison and Wiliot is helping make this vision tangible. Avery Dennison brings decades of expertise in intelligent labels, RFID, and digital identity while Wiliot brings battery-free Bluetooth tags capable of sensing and transmitting data using ambient energy. Together, they are helping push products from “tagged” to “connected.”
“BLE is a complementary technology to RFID. It increases the total addressable market and allows us to provide a broader set of solutions for improved visibility and condition monitoring for our customers, unlocking important data sets not possible before. With our strategic investment in Wiliot, we meet growing market demands to create value by connecting the physical and digital worlds.”, said Francisco Melo, president, intelligent labels technologies and digital solutions for Avery Dennison in a release announcing Avery Dennison’s $75 Million Investment in Wiliot.
For Walmart and other major retailers, this could make Ambient IoT operationally viable.
Avery Dennison brings:
• Deep expertise in RFID and intelligent labels
• Global supply chain relationships
• Digital identity infrastructure
Wiliot contributes:
• Battery-free Bluetooth tags
• Passive sensing technologies
• Cloud software for item-level intelligence
Together, they address scale manufacturing of labels, standards compatibility, enterprise data integration, supply chain deployment models, and software layers that turn sensor signals into usable intelligence.
Where RFID Fits in the Mix
One misconception is that passive BLE replaces RFID technology but that is far from the truth. RFID is the most preferred trace and track technology nowadays. Retailers like Walmart, Zara, Tesco, H&M, Decathlon, etc. have already deployed it. RFID technology co-exist with BLE.
RFID excels at:
• Fast identification
• Inventory accuracy
• High-volume item reads
• Proven operational scalability
Passive BLE adds:
• Environmental sensing
• Continuous condition monitoring
• Standard smartphone/BLE interactions
• Dynamic product telemetry
Together, they create a richer retail data layer. It means that rather than RFID versus passive BLE, the future may be RFID plus Ambient IoT.
Key Benefits of Ambient IoT for Retailers
a. Smart Retail and Loss Prevention
Passive BLE could support smarter Electronic Article Surveillance (EAS), theft prevention, and frictionless checkout while improving real-time inventory intelligence.
b. Ultra-Low-Cost Intelligence at Item Level
Without bulky batteries or traditional transmitters, tags can be produced at much lower cost and embedded into packaging.
That expands viability for mass-market retail.
c. Miniaturization for New Use Cases
Small, thin battery-free tags can fit where active electronics cannot, inside packaging, labels, walls, fixtures, or structural assets.
d. Cold-Chain and Fresh Food Monitoring
Ultra-small battery-free tags can support continuous environmental sensing for perishables in transit and in-store.
e. Smart Buildings and Store Operations
Embedded battery-free sensors could monitor:
• Temperature
• Humidity
• Occupancy
• Equipment conditions
Without maintenance-intensive battery replacements.
f. Asset Tracking
Passive or semi-passive BLE beacons can help track tools, fixtures, carts, and warehouse assets.
Where AI Changes the Equation
Passive BLE generates data and AI can create value from it helping retailers with:
1. Predictive Freshness and Waste Reduction
AI models can analyze temperature and handling data to predict spoilage risks before products reach shelves.
2. Inventory and Replenishment Forecasting
Sensor signals can improve demand planning and automate replenishment triggers.
3. Anomaly and Theft Detection
Unexpected movement patterns or environmental deviations can trigger alerts.
4. Autonomous Retail Decisioning
Over time, AI may help shift operations from alerts toward automated decisions:
a) Triggering replenishment
b) Routing at-risk products
c) Optimizing markdowns
d) Adjusting fulfillment logic
From Connected Products to Ambient Intelligence
Passive BLE represents more than a low-power wireless innovation- a broader shift from products that can be identified to products that can sense and to products that can inform AI. And ultimately, products that help drive autonomous operations.
That is the larger promise of Ambient IoT.
With Walmart’s fresh food priorities, Avery Dennison’s digital ID expertise, Wiliot’s battery-free innovation, and AI turning signals into intelligence, many of the foundational pieces are converging.
In short, RFID helped retailers know what they had. Passive BLE and AI may help them know what will happen next.
