manufacturer of electronic shelf labelsDevelopment division

Solving Power Problems in Pick-to-Light Fulfillment Systems“Pick-to-light” shelf label systems are indispensable in fulfillment centers but pose unique challenges.


In recent years, electronic shelf labels (ESLs) have become commonplace in many workplaces, including factories, warehouses, and hospitals. In factories and fulfilment centers, flashing LEDs on electronic shelf labels are used to facilitate the picking process* and clearly indicate where products and components should be stored. The technology helps improve efficiency, reduce mistakes, and alleviate labor shortages. The client, a developer and marketer of electronic shelf label systems, was attempting to find a quick solution to its flashing LED issues in order to satisfy its customers’ requirements.

*Picking: the process of selecting merchandise from inventory.


Battery Life a Problem

The electronic shelf labels used in factories and fulfilment centers are updated just as frequently as those used in retail applications. What’s more, the flashing LEDs mounted on the labels used in factory and warehouse applications need to be activated dozens, if not hundreds, of times each day. Because of this, while a primary or non-recharable battery will power an ESL used in a retail application for around five years, the batteries used in factories and warehouse applications need to be replaced every few months. Battery life is therefore a major issue for users and manufacturers alike. The client’s development team was attempting to find a solution to this issue by a process of trial and error.

Avoiding the Need for Mass Battery Replacement

In the course of developing their shelf label, the client encountered another problem. A single factory or warehouse would use anywhere from a few hundred to tens of thousands of the client’s ESLs. Replacing the batteries in so many labels was a major undertaking, especially if the label in question was designed to be waterproof, in which case batteries had to be removed using special tools, in what could be a difficult process. And even if it was possible to extend battery life, it would still only be a matter of months before the batteries would have to be replaced. The client began to consider the option of using a rechargeable battery with solar technology, but the factory was too dark for solar cells to generate sufficient electric power, therefore the client determined that this solution would be difficult to implement. The development process ground to a halt.

Main Issues

  • The batteries used in the ESLs used in factories and fulfillment centers wear out quickly because of the need to activate flashing LEDs frequently.

  • While ESLs used in retail applications will run for around five years on a primary battery, those used in factories and warehouses need to have their batteries replaced every few months.

  • A single factory or fulfilment center use tens of thousands of these labels, making battery replacement a cumbersome task.

  • Factories are too dark for solar cells to generate enough electricity. If using conventional technology, combining a rechargeable battery with a photovoltaic cell would therefore not work.