Hunan Gold shares surge after large deposit found in China
The Geological Bureau of Hunan Province said on Thursday that it had detected more than 40 gold veins containing an estimated 300 tons of the precious metal.
US and China-based researchers developed a 3D, interconnected, thermally-conductive boron nitride network that greatly improves thermal conductivity compared to random distribution in lithium-ion batteries.
In a paper published in the journal Green Energy & Environment, the scientists explain that although electric cars can now cover longer distances between charges and battery charging times have reduced, the lifespan of those batteries has also decreased and low heat dissipation efficiency has led to safety issues. Their development, thus, aims to address these shortcomings.
By systematically studying the effects of the three-dimensional network of boron nitride on the thermal management performance of power cells, the group found that the hexagonal boron nitride thermal network (h-BN) constructed by the ice template method with varying temperature gradients showed structural differences in different directions.
Ice templating, also known as freeze casting, is a popular shaping route for macroporous materials.
“Generally, structure determines performance, and different structures in different directions means a greater spread of performance,” study co-author Bing Zhang of China’s Zhejiang University, said in a media statement. “And by creating a composite with paraffin (h-BN/PW), we could achieve excellent anti-leakage performance and ultra-fast heat dissipation performance in lithium-ion batteries.”
According to Zhang, the results show that the maximum surface temperature of the battery with continuous charge and discharge at 2℃-5℃ was reduced by 6.9℃.
“We think that this demonstrates the great potential of this process for application in battery thermal management systems,” the scientist said.
