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Chatting on your phone drains its battery, but in the future, all this talk time could actually be used to boost its power.

Researchers from Canada have created a chin strap that harvests energy from jaw movements, including chewing and talking.

It is hoped the device could soon be used to power electronic devices, such as hearing aids, cochlear implants, and even phones.

The chin strap, (setup pictured) is made from a smart piezoelectric material known as PFC, which consists of integrated electrodes and adhesive polymer. It produces an electric charge when it stretches, and is subjected to mechanical stress

The strap is made from a smart material known as PFC. PFC is a type of piezoelectric material made up of integrated electrodes, and an adhesive polymer matrix.

The material is able to produce an electric charge when it stretches, and is subjected to mechanical stress.

In their study, researchers from Sonomax-ÉTS Industrial Research Chair in In-ear Technologies (CRITIAS) in Montreal, Canada, created an energy harvesting strap made from a single layer of PFC and attached it to a pair of ear muffs using a pair of elastic side straps.

To ensure maximum performance, the chin strap was fitted snugly to the user, so when the user's jaw moved it caused the strap to stretch.

To test the performance of the device, the subject was asked to chew gum for 60 seconds while wearing the head-mounted device.

The maximum amount of power that could be harvested from the jaw movements was around 18 microwatts, but researchers claim that a realistic output is closer to 10 microwatts.

This is still just a fraction of the energy used in a typical phone charger, which uses between 10 and 16 watts per day - but the strap is still in an experimental phase.

The first results of the device's performance have been published in IOP Publishing's journal Smart Materials and Structures.

Jaw movements proved to be one of the most promising candidates for generating electricity from human body movements, with researchers estimating that an average of around seven microwatts of power could be generated from chewing during meals alone.

Co-author of the study Aidin Delnavaz said: 'Given that the average power available from chewing is around seven microwatts, we still have a long way to go before we perfect the performance of the device.

To ensure maximum performance, the chin strap was fitted snugly to the user, so when the user's jaw moved it caused the strap to stretch. The maximum amount of power harvested from the chin strap (pictured) was 18 microwatts, but researchers are working on increasing this output significantly

'The power level we achieved is hardly sufficient for powering electrical devices at the moment; however, we can multiply the power output by adding more PFC layers to the chin strap.

'For example, 20 PFC layers, with a total thickness of 6mm, would be able to power a 200 microwatts intelligent hearing protector.

'The only expensive part of the energy harvesting device is the single PFC layer, which costs around $20 (£12).

'Considering the price and short lifetime of batteries, we estimate that a self-powered hearing protector based on the proposed chin strap energy harvesting device will start to pay back the investment after three years of use,' continued Delnavaz.

'Additionally, the device could substantially decrease the environmental impact of batteries and bring more comfort to users.

'We will now look at ways to increase the number of piezoelectric elements in the chin strap to supply the power that small electronic devices demand, and also develop an appropriate power management circuit so that a tiny, rechargeable battery can be integrated into the device.'