Summary of One step closer to the ‘ultimate battery’
The University of Cambridge has developed a lab-based lithium-air (Li-air) battery demonstrator, offering 10 times the energy density of Li-ion batteries and over 2,000 recharge cycles. While promising for electric vehicles, the technology requires another decade to stabilize for widespread use due to challenges with unwanted chemical reactions from air impurities like carbon dioxide, nitrogen, and moisture.
Parts used in the Lithium-Air Battery Demonstrator:
- Lithium compound electrode material
- Anode for lithium oxidation
- Cathode for oxygen reduction
- Graphene electrode
- Pure oxygen source
Although scientists are still working toward replacing lithium-ion (Li-ion) batteries with lithium-air (Li-air), or lithium-oxygen, batteries, researchers at the University of Cambridge have developed a lab-based demonstrator of such a battery. It is safe to say we still have another decade before we can begin to utilize such powerful batteries as scientists work to make sure it is stable enough for widespread use.
With a theoretical energy density that is being compared to gasoline, Li-air batteries are expected to have 10× the energy density of a Li-ion battery. With the ability to be recharged more than 2,000×, this battery is 90% more efficient. The future goal? To use lithium-air batteries for electric vehicles. Some challenges still need to be faced first for chemical reactions need to be reduced.
Unlike in the Li-ion rechargeable battery, in which lithium ions move from a negative electrode to a positive electrode and back during discharge and while charging, inserting a lithium compound as one electrode material, the Li-air battery uses oxidation of lithium at the anode with reduction of oxygen at the cathode to induce a current flow. Unfortunately, Li-air batteries are not ready for everyday use just yet. According to Dr. Tao Liu from the Department of Chemistry at the University of Cambridge, “There’s still a lot of work to do, but what we’ve seen here suggests that there are ways to solve these problems – maybe we’ve just got to look at things a little differently.”
Unwanted chemical reactions and the fact that they can only be cycled in pure oxygen are stumbling blocks. Using a graphene electrode, carbon dioxide, nitrogen, and moisture are all harmful. Being that the air around us contains all of that, researchers must find a way to cycle only pure oxygen in order to protect the electrode.
For more detail: One step closer to the ‘ultimate battery’
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What is the expected energy density of Li-air batteries compared to Li-ion?
Li-air batteries are expected to have 10 times the energy density of a Li-ion battery. -
How many times can the Li-air battery be recharged?
This battery can be recharged more than 2,000 times. -
When will Li-air batteries be ready for widespread use?
Scientists estimate it will take another decade before these batteries are stable enough for widespread use. -
What is the primary goal for using Li-air batteries?
The future goal is to use lithium-air batteries for electric vehicles. -
Why must researchers cycle only pure oxygen?
Researchers must cycle only pure oxygen because carbon dioxide, nitrogen, and moisture in regular air are harmful to the graphene electrode. -
Does the Li-air battery work differently than a Li-ion battery?
Yes, unlike Li-ion batteries where lithium ions move between electrodes, Li-air batteries use oxidation of lithium at the anode and reduction of oxygen at the cathode. -
What are the main stumbling blocks for Li-air batteries?
The main stumbling blocks are unwanted chemical reactions and the requirement to cycle only in pure oxygen.
