Anglia Live

The innovative cells from VARTA Microbattery produce ultrapure Hydrogen gas when a short circuit is applied across the device, which can then be used to provide mechanical displacement in applications such as precise dispensing of small amounts of liquid, gel, paste or granules.

Traditionally, mechanical displacement is provided by actuators, springs or gears, however there is often a limit to the size that these systems can be scaled down to. As a result they can become overly expensive, cumbersome and bulky particularly where dosing of micro-quantities of materials is required.

This latest device from VARTA Microbattery offers a new approach to the problem, requiring no electrical power supply and no springs, gears or other actuation components thus making it far cheaper and easier to implement than electro-mechanical or spring-loaded systems. It promises to open up a radically new approach to the design and assembly of small displacement devices.

The H2 cell from VARTA Microbattery is the same shape as a button (round) battery cell and can generate a volume of pure hydrogen 270 times greater than its own volume. Available in 2 configurations, single and double cell, the products can deliver H2 gas output of 130ml and 260ml respectively.

Fig 1: rate of gas emission from and H2 cell at room temperature and at various resistance values.

When controlled by a fixed value resistor, the rate of gas emission is constant. The resistance can also be provided by a variable potentiometer and this enables the user to adjust the rate of gas emission during operation. The rate is adjustable over a wide range, so that the cell can be used over a period as short as a matter of minutes to as long as a year.

When placed inside a gas-tight housing and activated, the cell’s release of gas generates pressure. In a device such as a syringe, this pressure will be converted into motive force. Hence a H2 cell can be used to drive a displacement device, and thus to dispense materials such as lubricants and medicines. A single V 130 H2 cell is capable of lifting a 10kg weight 10cm in the air when housed in a gas-tight, high-pressure enclosure.

It can be used as an alternative to a motor-driven or spring-loaded dispensing or actuation system, eliminating the requirement for micro-machined parts and an external power source. In dispensing applications, the only components required are the cell, connected to a resistor or potentiometer, and a gas-tight enclosure.

Compared to a mechanical drive system, the bill-of-materials cost is far lower, the design is simpler and there is far less risk of failure or component fatigue allowing the H2 cell to be used in a wide range of applications including drug delivery, lubrication, calibration, fuel cell, animal feed systems, laboratory, measurement, scent dispensers, leakage detection and analysis to name just a few.