2-In-1 Solar Charger Both Captures And Stores Energy

This integrated solar charger is fully charged after just two minutes in sunlight and can be used to power devices like mobile phones.

AsianScientist (May 8, 2017) – By combining high-efficiency silicon solar cells and lithium-ion battery technology, researchers have developed a single-unit, light-rechargable power source. Their results have been published in Energy & Environmental Science.

This newly-developed power source is designed to work under sunlight and indoor lighting, allowing users to power their portable electronics anywhere with access to light. In addition, the new device could power electric devices even in the absence of light.

In this work, the team of Professor Lee Sang-Young and Professor Seo Kwanyoung of the Ulsan National Institute of Science and Technology (UNIST) used miniaturized crystalline silicon photovoltaics (c-Si PVs) and printed solid-state lithium-ion batteries (LIBs). They used a thin-film printing technique in which the solid-state LIB is directly printed on the high-efficiency c-Si PV module.

To enable the seamless architectural and electrical connection of the two different energy systems, the aluminium metal layer is simultaneously used as a current collector of the LIB, as well as an electrode for solar cells. This allows the battery to be charged without the loss of energy.

“This device provides a solution to fix both the energy density problem of batteries and the energy storage concerns of solar cells,” said Lee. “More importantly, batteries have relatively high power and energy densities under direct sunlight, which demonstrates its potential application as a solar-driven infinite energy conversion/storage system for use in electric vehicles and portable electronics.”

According to the research team, this single-unit PV-LIB device has exceptional photo-electrochemical performance and design compactness that lie far beyond those achievable by conventional PVs or LIBs alone.

The researchers connected the device to various portable electronics to explore its practical use. For example, they fabricated a monolithically integrated smartcard by inserting the SiPV-LIB device into a pre-cut credit card. Then, electric circuits were drawn on the back of the credit card using a commercial silver pen to connect the SiPV-LIB device with an LED lamp. The SiPV-LIB device was also used to power a smartphone and an MP3 player.

The SiPV-LIB device was capable of fully charging under sunlight illumination after only two minutes. It also showed decent photo-rechargeable electric energy storage behavior even at a high temperature of 60°C and even at an extremely low light intensity of 8 mWcm/2, which corresponds to the intensity in a dimly-lit living room.

“The SiPV-LIB device presented herein shows great potential as a photo-rechargeable mobile power source that will play a pivotal role in the future era of ubiquitous electronics,” said Lee.

The article can be found at: Um et al. (2017) Monolithically Integrated, Photo-rechargeable Portable Power Sources Based on Miniaturized Si Solar Cells and Printed Solid-state Lithium-ion Batteries.


Source: Ulsan National Institute of Science and Technology.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

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