Researchers build non-explosive lithium battery

Posted on 12 Sep 2017 by Michael Cruickshank

US researchers have developed a new kind of lithium-ion battery which cannot catch on fire or explode when stressed.

One of the experimental aqueous lithium-ion batteries. Image courtesy of US Army Laboratory.
One of the experimental aqueous lithium-ion batteries. Image courtesy of US Army Laboratory.

A team from the U.S. Army Research Laboratory and the University of Maryland designed a lithium-ion battery which made use of an aqueous solution.

These batteries would not catch on fire despite being punctured multiple times with a nail during tests run by the researchers.

Just as importantly, the batteries were able to generate 4 Volts of current, making them able to be used in a wide range of consumer electronics such as smartphones or laptops.

Earlier attempts to develop this kind of battery produced designs which could only generate up to 3 Volts of current, stymied by a problem called ‘cathodic discharge’ whereby the battery’s anode was degraded by the water-based electrolyte.

The new design, however, solves this problem through the use of a polymer gel which coats and protects the anode.

Current lithium-ion batteries are the most energy-dense form of battery storage commercially available, however, their volatile chemicals present a major problem for manufacturers.

If these batteries are overcharged, damaged or punctured, they react with the ambient air in a fiery explosion which can cause bodily harm or building damage.

In the past, poor battery quality has resulted in a number of electronic products being forced to undergo massive recalls due to their propensity to catch fire.

Among the most well-known of these debacles are the Samsung Galaxy Note 7 which caused a loss of billions for the South Korean company, and the range of products known as ‘hoverboards’, many of which were banned in certain markets.

“In the past, if you wanted high energy, you would choose a non-aqueous lithium-ion battery, but you would have to compromise on safety. If you preferred safety, you could use an aqueous battery such as nickel/metal hydride, but you would have to settle for lower energy,” said Kang Xu, from the US Army Research Laboratory.

“Now, we are showing that you can simultaneously have access to both high energy and high safety.”

The polymer gel chemistry, however, will have to be perfected before these batteries become widespread, with the researchers expecting it to be available within 5 years.