Energy

A peek into the future of lithium batteries

A peek into the future of lith...
The "battery window" allows the researchers to look inside the lithium cell as it goes through charge cycles, giving real-time visualization of the dendrites growing and receding
The "battery window" allows the researchers to look inside the lithium cell as it goes through charge cycles, giving real-time visualization of the dendrites growing and receding
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U of M researcher Neil Dasgupta and his team look at the battery window assembly
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U of M researcher Neil Dasgupta and his team look at the battery window assembly
The "battery window" allows the researchers to look inside the lithium cell as it goes through charge cycles, giving real-time visualization of the dendrites growing and receding
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The "battery window" allows the researchers to look inside the lithium cell as it goes through charge cycles, giving real-time visualization of the dendrites growing and receding
The battery windows are designed to fit within a research camera's microscopic bay
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The battery windows are designed to fit within a research camera's microscopic bay
The team describes the dendrites growing as “organic, like plants growing and withering over the course of a battery cycle”
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The team describes the dendrites growing as “organic, like plants growing and withering over the course of a battery cycle”
View gallery - 4 images

In a great example of a low-cost research solution that could deliver big results, University of Michigan scientists have created a window for lithium-based batteries in order to film them as they charge and discharge.

The future of lithium-ion batteries is limited, says University of Michigan researcher Neil Dasgupta, because the chemistry cannot be pushed much further than it already has. Next-generation lithium cells will likely use lithium air and lithium sulfur chemistries. One of the big hurdles to be overcome in making these batteries practical is dendrites - tiny branch-like structures of lithium that form on the electrodes.

Dendrites can pierce cell walls or limit the lithium's potential. Neither is good for battery efficiency and can even lead to fires and explosions like those that have plagued the Samsung Galaxy Note 7 – though the jury is still out on exactly what caused the Note 7's well documented woes.

The team describes the dendrites growing as “organic, like plants growing and withering over the course of a battery cycle”
The team describes the dendrites growing as “organic, like plants growing and withering over the course of a battery cycle”

Battery cells are normally tested through cycles of charge and discharge, testing the capacity and flow potential of the cells before being dissected. Dasgupta and his team took a different approach. They added a window to a lithium cell so that they could film the dendrites forming and deforming during charge and discharge cycles. This has helped the team gain new insight into how dendrites form in real-time and how they can be mitigated.

They found that as the battery cycled, dendrites would grow during lithium accumulation on the electrode and then shrink on the reverse cycle. As the lithium pulled away from the electrode's surface, small pits in the metal were left behind. These pits became nucleation sites for dendrites during the next cycle. With each cycle, the dendrites grew larger. The team describes the dendrites growing as "organic, like plants growing and withering over the course of a battery cycle."

The battery windows are designed to fit within a research camera's microscopic bay
The battery windows are designed to fit within a research camera's microscopic bay

Dendrites can also be beneficial to the battery's process, the team found. If the dendrites grow in an even carpet over the battery's interior, remaining small, they can keep more lithium in play during the process, keeping battery performance stable. The U of M team believes that learning to control dendrites in an optimal way should be the goal of battery design going forward, because eliminating them altogether is not very likely.

The team says that the window solution is usable by researchers globally and costs about US$100 to implement. The findings have been published in ACS Central Science.

Dasgupta discusses the research in the following video.

New visualization technique to study lithium metal batteries

Source: University of Michigan

View gallery - 4 images
3 comments
Future3000
There are a lot of better battery types, but they "prefer" Li-Ion because Goldman Sachs earned nearly all tradings licenses of Lithium for the next 20 years AND all trading licenses for CO²-certificates. Coincidence?
LukaPotočnik
stop the conspiracies please... they knew like any sane person does that lithium price will rise and did what any person with money looking to make more money out of it would do...
ThadeusPaskalKebubun
thats why we need to solve hydrogen production and storage problem,lets make sure the future is where everybody can make it NOT where anybody can buy it.