Battery Power - Summer 2016 - (Page 16)
Research & Development
UCI Chemists Create Battery Technology with Off-the-Charts Charging Capacity
University of California, Irvine researchers have invented nanowire-based battery material that can be
recharged hundreds of thousands of times, moving us closer to a battery that would never require replacement. The breakthrough work could lead to commercial batteries with greatly lengthened lifespans
for computers, smartphones, appliances, cars and spacecraft.
Scientists have long sought to use nanowires in batteries.
Thousands of times thinner than a human hair, they're
highly conductive and feature a large surface area for the
storage and transfer of electrons. However, these filaments are extremely fragile and don't hold up well to repeated discharging and recharging, or cycling. In a typical
lithium-ion battery, they expand and grow brittle, which
leads to cracking.
UCI researchers have solved this problem by coating a
gold nanowire in a manganese dioxide shell and encasing the assembly in an electrolyte made of a Plexiglas-like
gel. The combination is reliable and resistant to failure.
The study leader, UCI doctoral candidate Mya Le Thai, cycled the testing electrode up to 200,000 times over three
months without detecting any loss of capacity or power
and without fracturing any nanowires.
UCI chemist Reginald Penner and doctoral candidate
Mya Le Thai (shown) have developed a nanowire-based
technology that allows lithium-ion batteries to be recharged hundreds of thousands of times. Steve Zylius / UCI
Hard work combined with serendipity paid off in this case, according to senior author Reginald Penner.
"Mya was playing around, and she coated this whole thing with a very thin gel layer and started to cycle
it," said Penner, chair of UCI's chemistry department. "She discovered that just by using this gel, she
could cycle it hundreds of thousands of times without losing any capacity."
"That was crazy," he added, "because these things typically die in dramatic fashion after 5,000 or 6,000
or 7,000 cycles at most."
The researchers think the goo plasticizes the metal oxide in the battery and gives it flexibility, preventing cracking.
"The coated electrode holds its shape much better, making it a more reliable option," Thai said. "This
research proves that a nanowire-based battery electrode can have a long lifetime and that we can make
these kinds of batteries a reality."
The study was conducted in coordination with the Nanostructures for Electrical Energy Storage Energy
Frontier Research Center at the University of Maryland, with funding from the Basic Energy Sciences
division of the US Department of Energy.
Researchers Developed Manufacturing Method for Microbatteries with Organic Electrode Materials
With people wanting to use smaller electronic devices, smaller energy storage systems are needed.
Researchers of Aalto University in Finland have demonstrated the fabrication of electrochemically active
organic lithium electrode thin films, which help make microbatteries more efficient than before. Researchers used a combined atomic/molecular layer deposition (ALD/MLD) technique, to prepare lithium
terephthalate, a recently found anode material for a lithium-ion battery.
When microbatteries are manufactured, the key challenge is to make them able to store large amounts of
energy in a small space. One way to improve the energy density is to manufacure the batteries based on
three-dimensional microstructured architectures. This may increase the effective surface inside a battery,
Battery Power * Summer 2016
Table of Contents for the Digital Edition of Battery Power - Summer 2016
Toolbox Energy Storage Systems: Modeling, Simulating and Testing Battery Systems of (H)EVs
Enhancing Smartphone Battery Performance During GSM Pulses Through The Use of a Parallel Supercapacitor
ICs & Semiconductors
Testing & Monitoring
Research & Development
Calendar of Events
Battery Power - Summer 2016