Tag Archives: Tian Zhou

The volatile lithium-ion battery

On the heels of Samsung’s Galaxy Note 7 recall due to fires (see Alex Fitzpatrick’s Sept. 9, 2016 article for Time magazine for a good description of lithium-ion batteries and why they catch fire; see my May 29, 2013 posting on lithium-ion batteries, fires [including the airplane fires], and nanotechnology risk assessments), there’s new research on lithium-ion batteries and fires from China. From an Oct. 21, 2016 news item on Nanotechnology Now,

Dozens of dangerous gases are produced by the batteries found in billions of consumer devices, like smartphones and tablets, according to a new study. The research, published in Nano Energy, identified more than 100 toxic gases released by lithium batteries, including carbon monoxide.

An Oct. 20, 2016 Elsevier Publishing press release (also on EurekAlert), which originated the news item, expands on the theme,

The gases are potentially fatal, they can cause strong irritations to the skin, eyes and nasal passages, and harm the wider environment. The researchers behind the study, from the Institute of NBC Defence and Tsinghua University in China, say many people may be unaware of the dangers of overheating, damaging or using a disreputable charger for their rechargeable devices.

In the new study, the researchers investigated a type of rechargeable battery, known as a “lithium-ion” battery, which is placed in two billion consumer devices every year.

“Nowadays, lithium-ion batteries are being actively promoted by many governments all over the world as a viable energy solution to power everything from electric vehicles to mobile devices. The lithium-ion battery is used by millions of families, so it is imperative that the general public understand the risks behind this energy source,” explained Dr. Jie Sun, lead author and professor at the Institute of NBC Defence.

The dangers of exploding batteries have led manufacturers to recall millions of devices: Dell recalled four million laptops in 2006 and millions of Samsung Galaxy Note 7 devices were recalled this month after reports of battery fires. But the threats posed by toxic gas emissions and the source of these emissions are not well understood.

Dr. Sun and her colleagues identified several factors that can cause an increase in the concentration of the toxic gases emitted. A fully charged battery will release more toxic gases than a battery with 50 percent charge, for example. The chemicals contained in the batteries and their capacity to release charge also affected the concentrations and types of toxic gases released.

Identifying the gases produced and the reasons for their emission gives manufacturers a better understanding of how to reduce toxic emissions and protect the wider public, as lithium-ion batteries are used in a wide range of environments.

“Such dangerous substances, in particular carbon monoxide, have the potential to cause serious harm within a short period of time if they leak inside a small, sealed environment, such as the interior of a car or an airplane compartment,” Dr. Sun said.

Almost 20,000 lithium-ion batteries were heated to the point of combustion in the study, causing most devices to explode and all to emit a range of toxic gases. Batteries can be exposed to such temperature extremes in the real world, for example, if the battery overheats or is damaged in some way.

The researchers now plan to develop this detection technique to improve the safety of lithium-ion batteries so they can be used to power the electric vehicles of the future safely.

“We hope this research will allow the lithium-ion battery industry and electric vehicle sector to continue to expand and develop with a greater understanding of the potential hazards and ways to combat these issues,” Sun concluded.

Here’s a link to and a citation for the paper,

Toxicity, a serious concern of thermal runaway from commercial Li-ion battery by Jie Sun, Jigang Li, Tian Zhou, Kai Yang, Shouping Wei, Na Tang, Nannan Dang, Hong Li, Xinping Qiu, Liquan Chend. Nano Energy Volume 27, September 2016, Pages 313–319  http://dx.doi.org/10.1016/j.nanoen.2016.06.031

This paper appears to be open access.

Fish skin for wound healing

A Feb. 11, 2015 news item on Nanowerk features Chinese research on tilapia fish skin and possible applications for wound healing (Note: A link has been removed),

With a low price tag and mild flavor, tilapia has become a staple dinnertime fish for many Americans. Now it could have another use: helping to heal our wounds. In the journal ACS Applied Materials & Interfaces (“Development of Biomimetic Tilapia Collagen Nanofibers for Skin Regeneration through Inducing Keratinocytes Differentiation and Collagen Synthesis of Dermal Fibroblasts”), scientists have shown that a protein found in this fish can promote skin repair in rats without an immune reaction, suggesting possible future use for human patients.

A Feb. 11, 2015 American Chemical Society (ACS) news release, which originated the news item, provides a few more details about the work,

Jiao Sun, Xiumei Mo and colleagues explain that applying collagen — a major structural protein in animals — to wounds can help encourage skin to heal faster.  But when the protein dressing comes from mammals such as cows and pigs, it has the potential to transmit conditions such as foot-and-mouth disease. Searching for an alternative source of collagen, scientists recently turned to the ocean. Sun’s team wanted to test fish collagen’s potential as a more benign wound treatment.

The researchers developed nanofibers from tilapia collagen and used them to cover skin wounds on rats. The rats with the nanofiber dressing healed faster than those without it. In addition, lab tests on cells suggested that the fish collagen was not likely to cause an immune reaction. The researchers conclude that it could be a good candidate to develop for clinical use.

Here’s a link to and a citation for the paper,

Development of Biomimetic Tilapia Collagen Nanofibers for Skin Regeneration through Inducing Keratinocytes Differentiation and Collagen Synthesis of Dermal Fibroblasts by Tian Zhou, Nanping Wang, Yang Xue, Tingting Ding, Xin Liu, Xiumei Mo, and Jiao Sun. ACS Appl. Mater. Interfaces, 2015, 7 (5), pp 3253–3262 DOI: 10.1021/am507990m Publication Date (Web): January 19, 2015

Copyright © 2015 American Chemical Society

This article is behind a paywall.