This image shows the interfacial orbital ordering found in the spinel-layered interface.
(Photo source: DOI number: 10.1038/s41893-020-00660-9)
The promotion of electric cars has dramatically increased the demand for lithium-ion batteries. However, cobalt and nickel, the main cathode materials for the batteries, are not abundant. If the consumption continues, it will inevitably elevate the costs in the long run, so scientists have been actively developing alternative materials. A joint research team co-led by a scientist from City University of Hong Kong (CityU) has developed a much more stable, manganese-based cathode material.
The new material has higher capacity and is more durable than the existing cobalt and nickel cathode materials – 90% of capacity is retained even when the number of charging-recharging cycles doubled. Their findings shed lights on developing low cost and high efficiency manganese-based cathode materials for lithium-ion batteries.
The research team was co-led by Dr Liu Qi, Assistant Professor in the Department of Physics (PHY) at CityU, together with scientists from Nanjing University of Science and Technology (NUST), and the Institute of Physics, Chinese Academy of Sciences (IOPCAS). Their findings have been published in the scientific journal Nature Sustainability, titled “LiMnO2 cathode stabilized by interfacial orbital ordering for sustainable lithium-ion batteries”.
Technology bottleneck of manganese-based cathode materials: low capacity retention
Lithium-ion batteries are now widely used in cell phones and electric cars. Most of the cathode materials contain cobalt and nickel, which are both not abundant and create pollution to the environment in the exploitation process. Therefore, scientists are searching for alternative cathode materials, for example, manganese (Mn).
Among the leading manganese-based candidates, LiMnO2 is cost-effective, more environmentally friendly with larger theoretical capacity. However, it suffers from poor stability during the charging-recharging cycle. Breaking of grains, rapid structural degradation and serious dissolution of manganese may happen. Severe capacity decay upon cycling is resulted and therefore shortens its durability, hindering the application of LiMnO2 in the commercialised lithium-ion batteries.
Jahn-Teller distortion needs to be suppressed
Dr Liu, an expert in developing cathode materials for lithium-ion batteries, pointed out that the structural instability of manganese-based materials is mainly caused by the Jahn-Teller distortion in their atomic structure. Upon discharging, the Mn-O bond in LiMnO2 will be elongated, which is called Jahn-Teller distortion. Since there is a long-range collinear orbital ordering of the electron orbits of the Mn3+ ions without disturbance, a strong cooperative Jahn–Teller distortion is resulted. Their atomic structures are easily distorted.
Dr Liu and his team tackled the problem by applying interfacial engineering in the atomic structure, which disturbs the long-range collinear orbital ordering and suppresses a large scale of Jahn–Teller distortion.
Structural stability enhanced by interfacial engineering
The team prepared the spinel–layered (heterostructured) LiMnO2 via in situ electrochemical conversion from spinel Mn3O4 nanowall arrays. It is found that the electron orbits are oriented almost perpendicular to each other between the spinel and layered boundaries, resulted in the interfacial orbital ordering. “This has caused a disturbance of the long-range collinear orbital ordering, therefore Jahn–Teller distortion is suppressed,” explained Dr Liu.
Their experiment results showed that Jahn–Teller distortion was effectively suppressed with this heterostructure design. The degrees of distortion of the layered and spinel phase was only 2.5% and 5.5% respectively, while layered LiMnO2 and spinel LiMnO2 showed much greater degrees of distortion of 18% and 16% respectively. This implies that the heterostructured LiMnO2 exhibited much higher structural stability. The team also found that the volume changes from the spinel and layered phases counteract with each other, leading to a minimal total volume change for the material. As a result, the material exhibited superior structural stability.
Long cycle life
“The capacity of the LiCoO2 cathode material currently applied in electronic products like smartphones is about 165mAh/g, while our LiMnO2 cathode material has already achieved a capacity as high as 254.3 mAh g?1, which is much higher,” Dr Liu elaborated. “It is difficult for commercial LiCoO2 to maintain 90% capacity even at 1,000 cycles. And our material has achieved high capacity retention of 90.4% after 2,000 cycles, demonstrating a long cycle life,” he added.
They are the first team to deploy interfacial orbital ordering to suppress the Jahn–Teller distortion. This novel method facilitated the development of sustainable Mn-rich cathode materials, in the hope of applying them in sustainable and commercialised energy storage devices. “We look forward to cost reduction in energy storage technology which can promote the energy structure in moving towards sustainability. Our material can potentially replace the currently commercialised cobalt materials for applications such as electronics and electric cars,” concluded Dr Liu.
The Latest Updates from Bing News & Google News
Go deeper with Bing News on:
- CBAK Energy Announces SGS Certification of Battery for Ultra-Low Temperature Applicationon August 23, 2021 at 5:01 am
CBAK Energy Technology, Inc. (NASDAQ: CBAT) ("CBAK Energy", or the "Company"), a leading lithium-ion battery manufacturer and electric energy solution provider, today announced that its wholly-owned ...
- Tianqi, IGO produce first Australian lithium hydroxide for batterieson August 22, 2021 at 3:37 pm
A joint venture between Tianqi Lithium and IGO Ltd has produced Australia's first batch of lithium hydroxide, as demand for the chemical used in electric-vehicle (EV) batteries is set to gain speed, ...
- GM’s recall of all Bolt EVs raises questions about lithium ion batterieson August 22, 2021 at 4:12 am
General Motors is recalling all Chevrolet Bolt electric vehicles sold worldwide to fix a battery problem that could cause fires. Here's the latest.
- All Chevy Bolts Recalled Over Fire Risk From Lithium Ion Batterieson August 20, 2021 at 2:20 pm
The recall, which will cost GM $1 billion, adds roughly 73,000 vehicles from the 2019 through 2022 model years to a prior recall of 69,000 older models.
- Lithium-ion Batteries to be Commonplace in Solar Powered Cars, Every 9 out of 10 Cars to Have it by 2031on August 20, 2021 at 7:31 am
As per insights by Fact.MR, the global market for solar powered car is anticipated to rise at a CAGR of 12.3% between 2021 and 2031, surpassing market valuation of US$ 90 Mn by the end of 2022.
Go deeper with Google Headlines on:
Go deeper with Bing News on:
- Umicore in Patent Disputes in South Koreaon August 19, 2021 at 10:01 pm
The Ministry of Trade, Industry and Energy has decided to initiate an investigation whether two companies infringed upon Umicore’s cathode material patent rights. The petitioner is claiming that the t ...
- When will ASX manganese stocks join the battery metals boom?on August 15, 2021 at 4:42 pm
Manganese demand in lithium ion batteries will climb an astonishing 9.3 times between today and 2030. Here are the ASX manganese stocks to watch.
- American Manganese Receives Funding to Advance Lithium-Ion Battery Recycling Project in Collaboration with Italvolton August 14, 2021 at 8:58 am
In collaboration with Italvolt, American Manganese will model, commission, and test a lithium-ion battery cathode material recycling demonstration ... which are statements about the future based on ...
- American Manganese Receives Funding to Advance Lithium-Ion Battery Recycling Project in Collaboration with Italvolton August 13, 2021 at 6:00 pm
American Manganese Inc. is pleased to announce it is receiving advisory services and funding from the National Research Council of Canada Industrial Research Assistance Program to support a pilot ...
- American Manganese Inc.: American Manganese Receives Funding to Advance Lithium-Ion Battery Recycling Project in Collaboration with Italvolton August 13, 2021 at 1:08 pm
In collaboration with Italvolt, American Manganese will model, commission, and test a lithium-ion battery cathode material recycling ... about the future based on current expectations or beliefs.