ALD used in new 3D design for mobile microbatteries

Nanowerk News reports: In the race towards miniaturization, a French-US team-mostly involving researchers from the CNRS, Université de Lille, Université de Nantes and Argonne National Laboratory (US) as part of the Research Network on Electrochemical Energy Storage (RS2E)1-has succeeded in improving the energy density of a rechargeable battery without increasing its size (limited to a few square millimeters in mobile sensors).

Read more: New 3D design for mobile microbatteries

Atomic Layer Deposition of Functional Layers for on Chip 3D Li-Ion All Solid State Microbattery

Manon Létiche, Etienne Eustache, Jeremy Freixas, Arnaud Demortière, Vincent De Andrade, Laurence Morgenroth, Pascal Tilmant, François Vaurette, David Troadec, Pascal Roussel, Thierry Brousse and Christophe Lethien

 

Advanced Energy Materials, Version of Record online: 11 OCT 2016

DOI: 10.1002/aenm.201601402

Supporting Information : LINK

 

 (Graphical abstract Advanced Energy Materials)

 

Nowadays, millimeter scale power sources are key devices for providing autonomy to smart, connected, and miniaturized sensors. However, until now, planar solid state microbatteries do not yet exhibit a sufficient surface energy density. In that context, architectured 3D microbatteries appear therefore to be a good solution to improve the material mass loading while keeping small the footprint area. Beside the design itself of the 3D microbaterry, one important technological barrier to address is the conformal deposition of thin films (lithiated or not) on 3D structures. For that purpose, atomic layer deposition (ALD) technology is a powerful technique that enables conformal coatings of thin film on complex substrate. An original, robust, and highly efficient 3D scaffold is proposed to significantly improve the geometrical surface of miniaturized 3D microbattery. Four functional layers composing the 3D lithium ion microbattery stacking has been successfully deposited on simple and double microtubes 3D templates. In depth synchrotron X-ray nanotomography and high angle annular dark field transmission electron microscope analyses are used to study the interface between each layer. For the first time, using ALD, anatase TiO2 negative electrode is coated on 3D tubes with Li3PO4 lithium phosphate as electrolyte, opening the way to all solid-state 3D microbatteries. The surface capacity is significantly increased by the proposed topology (high area enlargement factor – “thick” 3D layer), from 3.5 μA h cm−2 for a planar layer up to 0.37 mA h cm−2 for a 3D thin film (105 times higher).

Development of safe and durable high-temperature lithium-sulfur batteries by ALD

(From Nanowerk News) Safety has always been a major concern for electric vehicles, especially preventing fire and explosion incidents with the best possible battery technologies. Lithium-sulfur batteries are considered as the most promising candidate for EVs due to their ultra-high energy density, which is over 5 times the capacity of standard commercial Li-ion batteries. This high density makes it possible for electric vehicles to travel longer distances without stopping for a charge. 

 

 

Scheme of MLD alucone coated C-S electrode and cycle performance of stabilized high temperature Li-S batteries. (Figure from Nanowerk News)

Read more: Development of safe and durable high-temperature lithium-sulfur batteries

However, batteries operating at the high temperatures necessary in electric vehicles presents a safety challenge, as fire and other incidents become more likely.

Prof. Andy Xueliang Sun and his University of Western Ontario research team, in collaboration with Dr. Yongfeng Hu and Dr. Qunfeng Xiao from the Canadian Light Source, have developed safe and durable high-temperature Li-S batteries using by a new coating technique called molecular layer deposition (MLD) technology for the first time. This research has been published in Nano Letters ("Safe and Durable High-Temperature Lithium–Sulfur Batteries via Molecular Layer Deposited Coating").


Read more: Development of safe and durable high-temperature lithium-sulfur batteries

Missouri S&T Team boosts lithium-ion battery performance with ALD

Researchers Missouri University of Science and Technology are working to solve the problem of short-life of lithium-ion batteries like those used in laptops and cellphones, making them reliable and longer-lasting using a atomic layer deposition. This study was carried out using a fluidized bed reactor.

Science Daily reports the following:

"Dr. Xinhua Liang, assistant professor of chemical and biochemical engineering at Missouri S&T, leads the study to dope and coat lithium magnesium nickel oxygen (LMNO) with iron oxide through ALD -- at the same time. Doping means adding an element or compound into the crystalline structure, or lattice, filling in the gaps in the LMNO. Coating is what it sounds like, putting ultra-thin layers of iron oxide around the whole compound. Rajankumar Patel, a Missouri S&T Ph.D. candidate in chemical engineering who will graduate next week, did the majority of the experimental work in the project

TEM images of (a) clean edge of an uncoated LiMn1.5Ni0.5O4 particle, and (b) ~3 nm of conformal iron oxide film coated on one LiMn1.5Ni0.5O4 particle after 160 cycles of iron oxide ALD, (c) cross sectional TEM image of one LiMn1.5Ni0.5O4 particle with 160 cycles of iron oxide ALD, (d) Fe element mapping of cross-sectioned surface by EDS, and (e) Fe EDS line scanning along the red line as shown in (c). TEM image indicates that conformal iron oxide films were coated on primary LiMn1.5Ni0.5O4 particle surface. EDS mapping and EDS element line scanning indicates that Fe was doped in the lattice structure of LiMn1.5Ni0.5O4. (From Open Source - Scientific Reports 6, Article number: 25293 (2016), doi:10.1038/srep25293)

The operating voltage window of LMNO makes it a potential candidate for use in hybrid electric vehicles (HEV). However, it has not gained commercial usability in HEV because of high-capacity fade during cycling at elevated temperatures and manganese(3+) dissolution by hydrogen fluorine.

"Unlike current research practice that either covers the particles' surface with insulating film or dopes the particles to improve the performance of the battery," Liang says, "this ALD process combines the coating and doping processes into one, and applying this technique makes rechargeable lithium-ion batteries last longer."

"This is the first report for a unique phenomenon of ionic iron entering the lattice structure of LMNO during the ALD coating process," Patel says.

Full story: https://www.sciencedaily.com/releases/2016/05/160505105220.htm and Open Source article below published in Scientific Reports.

Employing Synergetic Effect of Doping and Thin Film Coating to Boost the Performance of Lithium-Ion Battery Cathode Particles

Rajankumar L. Patel, Ying-Bing Jiang, Amitava Choudhury & Xinhua Liang

Scientific Reports 6, Article number: 25293 (2016), doi:10.1038/srep25293

Atomic layer deposition (ALD) has evolved as an important technique to coat conformal protective thin films on cathode and anode particles of lithium ion batteries to enhance their electrochemical performance. Coating a conformal, conductive and optimal ultrathin film on cathode particles has significantly increased the capacity retention and cycle life as demonstrated in our previous work. In this work, we have unearthed the synergetic effect of electrochemically active iron oxide films coating and partial doping of iron on LiMn1.5Ni0.5O4 (LMNO) particles. The ionic Fe penetrates into the lattice structure of LMNO during the ALD process. After the structural defects were saturated, the iron started participating in formation of ultrathin oxide films on LMNO particle surface. Owing to the conductive nature of iron oxide films, with an optimal film thickness of ~0.6 nm, the initial capacity improved by ~25% at room temperature and by ~26% at an elevated temperature of 55 °C at a 1C cycling rate. The synergy of doping of LMNO with iron combined with the conductive and protective nature of the optimal iron oxide film led to a high capacity retention (~93% at room temperature and ~91% at 55 °C) even after 1,000 cycles at a 1C cycling rate.

Picosun’s ALD solutions at Imec transform battery technology

ESPOO, Finland, 30th March, 2016 – Picosun Oy, the leading supplier of advanced ALD (Atomic Layer Deposition) thin film coating technology, now provides ALD equipment to transform battery manufacturing. 

 

Previous news here on the ALD Blog : Picosun teams up with IMEC to realize next generation’s battery technology with ALD
 

The sustainable energy economy of the future, greener transportation, and the increasing number of portable, mobile and personal electronic devices all require improved means for local energy storage. Nanostructured, solid-state thin film batteries offer a disruptive solution for this. Replacing traditionally used liquid materials in the battery with all solid layers improves the battery safety and lifetime. Thin and flat geometry makes the batteries easily integrated in e.g. wearable electronics, whereas their nanoscale tailored internal structure enables high energy storage capacity.

ALD is an ideal way to prepare the highly conformal, dense, uniform, and structurally and chemically exactly controlled functional layers in the core of the battery stack. Using PICOSUN™ ALD equipment, imec, Belgium, has now developed a solution to deposit a novel, solid electrolyte for lithium ion thin film batteries.

“Our aim at Picosun is to utilize ALD technology for better tomorrow. For example, faster and smoother data handling and communications, and the increasing number of mobile, wearable personal health monitoring devices require compact, efficient, and reliable power delivery solutions. The ALD technology we have now developed with imec for manufacturing of safe and long-lasting thin film batteries is an important breakthrough into a huge market area still relatively new to ALD. We are happy to provide the latest manufacturing solutions to our customers in this field and to see their most advanced products powering our everyday electronics,” states Juhana Kostamo, Managing Director of Picosun.

Atomic/Molecular Layer Deposition of Lithium Terephthalate for Li-Ion Battery Anodes

EurekAlert.org reports: When microbatteries are manufatured, 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- even dozens of times. However, the production of materials fit for these has proven to be very difficult.

Aalto University Researchers testing the material on coin cells. (Mikko Raskinen / Aalto University)

Researches at Aalto University, Helsinki Finland, has develooped a ALD/MLD deposition process for Li-terephthalate, which has been published in Nanoo Letters (below).

- ALD is a great method for making battery materials fit for 3D microstructured architectures. Our method shows it is possible to even produce organic electrode materials by using ALD, which increases the opportunities to manufacture efficient microbatteries, says doctoral candidate Mikko Nisula from Aalto University. (EurekAlert.org)

Atomic/Molecular Layer Deposition of Lithium Terephthalate Thin Films as High Rate Capability Li-Ion Battery Anodes

Nano Lett., 2016, 16 (2), pp 1276–1281

DOI: 10.1021/acs.nanolett.5b04604

We demonstrate the fabrication of high-quality electrochemically active organic lithium electrode thin films by the currently strongly emerging combined atomic/molecular layer deposition (ALD/MLD) technique using lithium terephthalate, a recently found anode material for lithium-ion battery (LIB), as a proof-of-the-concept material. Our deposition process for Li-terephthalate is shown to well comply with the basic principles of ALD-type growth including the sequential self-saturated surface reactions, a necessity when aiming at micro-LIB devices with three-dimensional architectures. The as-deposited films are found crystalline across the deposition temperature range of 200–280 °C, which is a trait highly desired for an electrode material but rather unusual for hybrid inorganic–organic thin films. Excellent rate capability is ascertained for the Li-terephthalate films with no conductive additives required. The electrode performance can be further enhanced by depositing a thin protective LiPON solid-state electrolyte layer on top of Li-terephthalate; this yields highly stable structures with capacity retention of over 97% after 200 charge/discharge cycles at 3.2 C.

Researchers at Case Western Reserve University directly photo-charged lithium batteries with 7.8 percent efficiency

As reported bu Phys.org : Researchers at Case Western Reserve University, however, have wired four perovskite solar cells (PSC) in series to enhance the voltage and directly photo-charged lithium batteries (LIB) with 7.8 percent efficiency—the most efficient reported to date, the researchers believe.

The research, published in the Aug. 27 issue of Nature Communications, holds promise for cleaner transportation, home power sources and more.

Efficiently photo-charging lithium-ion battery by perovskite solar cell [Open Access]

Jiantie Xu, Yonghua Chen & Liming Dai Nature Communications 6, Article number:8103 doi:10.1038/ncomms9103

 Schematic diagram of the fabricated system of PSC–LIB. (Nature Communications 6, Article number:8103)

Abstract:  Electric vehicles using lithium-ion battery pack(s) for propulsion have recently attracted a great deal of interest. The large-scale practical application of battery electric vehicles may not be realized unless lithium-ion batteries with self-charging suppliers will be developed. Solar cells offer an attractive option for directly photo-charging lithium-ion batteries. Here we demonstrate the use of perovskite solar cell packs with four single CH3NH3PbI3 based solar cells connected in series for directly photo-charging lithium-ion batteries assembled with a LiFePO4 cathode and a Li4Ti5O12 anode. Our device shows a high overall photo-electric conversion and storage efficiency of 7.80% and excellent cycling stability, which outperforms other reported lithium-ion batteries, lithium–air batteries, flow batteries and super-capacitors integrated with a photo-charging component. The newly developed self-chargeable units based on integrated perovskite solar cells and lithium-ion batteries hold promise for various potential applications.

The structure and the preparation procedures of CH3NH3PbI3 perovskite films (Supplementary information)

HERALD Workshop - ALD for Batteries, Gent, Belgium September 15-16

Workshop - ALD for Batteries

Co-organiser 

 

Program

Tuesday, September 15, 2015 - Het Pand

09:30   Registration

10:00   Philippe Vereecken, IMECInvited Talk - Conformal deposition for 3D thin-film batteries: requirements and opportunities

10:45   Sebastien Moitzheim, IMECSpatial ALD of TiO2 for 3D thin-film batteries

11:15   Felix Mattelaer, Ghent University
ALD of Manganese oxides

11:45   Mikko Ritala, University of HelsinkiPreparation of lithium containing ternary oxides by solid state reaction of atomic layer deposited thin films

12:15   Lunch

13:30   Maarit Karppinen, Aalto University
Invited Talk 

14:15   Kevin van de Kerckhove, Ghent University
Molecular Layer Deposition of Titanicone

14:45   Miia Mäntymäki, University of Helsinki

15:15   Break

15:45   Adriana Creatore, TU Eindhoven
Invited Talk - Plasma ALD of Li-based materials

16:30   Thomas Dobbelaere, Ghent University
ALD of phosphates

17:00   Closing remarks

Wednesday, September 16, 2015 - Dept. Solid State Sciences

09:00   Ola Nilsen, University of Oslo
Invited Talk - ALD of Li-containing compounds

09:45   Amund Ruud, University of Oslo
High rate iron phosphates by ALD

10:15   Break

10:45   Ruud Van Ommen, TU Delft
ALD on battery particles

11:30   Geert Rampelberg, Ghent University
Thermal and plasma enhanced ALD on powders

12:00   Lunch

13:30   Tour of the Lab 

Registration

Participation is free of charge (limited number of places):https://webapps.ugent.be/eventManager/events/cocoonworkshopbatteries

Registration will be possible from 1 July 2015. Please register before 1 September 2015. 

Location

The workshop takes place at Het Pand (on Tuesday) and the department of Solid State Sciences (on Wednesday).

Tuesday, September 15, 2015

Het Pand, Ghent University
Onderbergen 1
9000 Gent, Belgium

By public transport:

• From station Gent Sint-Pieters:Tram 1 (every 6 minutes) or tram 24 (every 20 minutes). Exit at Korenmarkt.
• From Gent ZuidTram 4 (every 6 minutes), tram 24 (every 20 minutes) or bus 17 (every 30 minutes). Exit at Korenmarkt.

By Car:

• Follow the parking signage to parking P7 Sint-Michiels. The parking is located at 50 meter from Het Pand. Take the exit Onderbergen and you come out in the wilderoosstraat, opposite Het Pand.
• An alternative parking is P8 Ramen. From here it's about 5 minutes on foot to Het Pand.

Wednesday, September 16, 2015

Department of Solid State Sciences, Ghent University
Krijgslaan 281 - Building S1
9000 Gent, Belgium

How to reach us

Contact

Department of Solid State Sciences, Ghent University

Krijgslaan 281 - Building S1
9000 Gent, Belgium

Phone: +32 (0)9 264 43 54
Fax: +32 (0)9 264 49 96

E-mail: Christophe.Detavernier@UGent.be

Flyer

Download here

Sponsors

 

Ultratech Cambridge NanoTech announced that the 1000th paper using one of their ALD tools

I previously posted this paper (here) and it turns out that this is as announced today by Ultratech Cambridge NanoTech, the 1000th peer-reviewed paper written on its ALD systems was published in July 2015 inChemistry of Materials. 

The paper entitled "Atomic Layer Deposition of the Solid Electrolyte LiPON" was authored by Alexander Kozen, Ph.D, a member of the Nanostructures for Electrical Energy Storage (NEES) group at the University of Maryland. This milestone figure underscores the fact that today, almost one-fifth of the total peer-reviewed ALD publications worldwide, since the founding of the company in 2003, have been written based on using Ultratech-CNT systems (based on Web of Science analysis). 

University of Maryland Professor and principal investigator at the Energy Frontier Research Center (EFRC) Gary Rubloff said, "The performance and flexibility of our Ultratech Fiji systems have driven our group's nano research since 2011. The role played by these systems has been critical in many of the advances made in Nanostructures for Electrical Energy Storage (NEES)--our DOE, Energy Frontier Research Center. The research undertaken has involved a variety of collaborations across the Center to exploit ALD films as cathode, anode, current collector, solid electrolyte, and passivation/stabilization layers distributed as highly conformal, high quality layers on 3-D structures in the most demanding nano-geometries. As part of our most recent work, we have just developed the first reported ALD process for lithium phosphorous oxy-nitride (LiPON), a well-known, solid-state electrolyte for safe batteries. Through the use of real-time, in-situ ellipsometry, the process was optimized in a systematic fashion. ALD allows us to grow very thin LiPON layers that we are applying to passivation of high-energy lithium anodes as well as to solid-state batteries."

Ultratech-CNT Vice President of Research and Engineering Ganesh Sundaram, Ph.D. said, "While the traditional gauge of system productivity has focused on metrics such as wafer output, we have chosen to concentrate on creating products which motivate and enable intellectual output. The 1000th paper milestone attests to the fact that the Ultratech-CNT ALD systems are at the forefront for generating high quality, and strongly-cited research in this fast growing field. Furthermore, the large library of research papers based on our systems also provides substantial benefits to new researchers entering the field as they will be able to take advantage of the solid foundation of published research that underpins these ALD systems."

Dr. Kozen is part of The Rubloff Group at the University of Maryland where Professor Gary Rubloff heads the Nanostructures for Electrical Energy Storage (NEES), Energy Frontier Research Center (EFRC), a program of the Department of Energy (DOE). The paper was published in Chemistry of Materials (DOI: 10.1021/acs.chemmater.5b01654).

Atomic Layer Deposition of the Solid Electrolyte LiPON for 3D solid state nanobatteries

Since its discovery in the early 1990s, LiPON (lithium phosphorus oxynitride) has been one of the most popular solid state electrolytes used for planar lithium ion microbatteries. University of Maryland demonstrate an ALD process for the solid electrolyte lithium phosphorousoxynitride (LiPON) using lithium tert-butoxide (LiOtBu), H2O, trimethylphosphate (TMP), and plasma N2 (PN2) as precursors using av Ultratech / Cambridge Naotech Fiji 200 PEALD reactor. The results are published in the Open Access article below.

ANSLab at the University of Maryland. Shown, from left to right, is a Cambridge Nanotech Fiji F200 ALD Tool (Luigi), a glovebox for working with air-sensitive materials, a rotary wafer transporter (R2P2), thermal evaporation chamber, and second Cambridge Nanotech Fiji F200 ALD tool (Mario). (source: http://www.terpconnect.umd.edu/~ackozen/Research.html)

Atomic Layer Deposition of the Solid Electrolyte LiPON (OPEN ACCESS)

Alexander C. Kozen, Alexander J. Pearse, Chuan-Fu Lin, Malachi Noked, and Gary W. Rubloff

Chem. Mater., Article ASAP
DOI: 10.1021/acs.chemmater.5b01654

We demonstrate an atomic layer deposition (ALD) process for the solid electrolyte lithium phosphorousoxynitride (LiPON) using lithium tert-butoxide (LiOtBu), H2O, trimethylphosphate (TMP), and plasma N2 (PN2) as precursors. We use in-situ spectroscopic ellipsometry to determine growth rates for process optimization to design a rational, quaternary precursor ALD process where only certain substrate–precursor chemical reactions are favorable. We demonstrate via in-situ XPS tunable nitrogen incorporation into the films by variation of the PN2dose and find that ALD films over approximately 4.5% nitrogen are amorphous, whereas LiPON ALD films with less than 4.5% nitrogen are polycrystalline. Finally, we characterize the ionic conductivity of the ALD films as a function of nitrogen content and demonstrate their functionality on a model battery electrode—a Si anode on a Cu current collector.

PneumatiCoat completes DOE Project for a Battery Pilot Plant and recieves US Navy funding

Battery cathode materials with improved safety and performance. Picoshield® coatings provide improvements on many of the most common Li-ion cathode materials used today. As the leader in ALD battery materials PneumatiCoat (PCT) can attain cutting edge performance out of existing battery materials, both cathode and anode. 

Recently has had success in finalizing and receiving additional DOE funded projects as reported here:

PCT Presenting at DOE Annual Merit Review in Arlington, VA

June 2015 - PCT is presenting the most recent results from our DOE Phase II project. With the completion of our pilot plant, large format Picoshield® battery cells are built and producing excellent data. The results expand on the positive work conducted during the Phase I by proving out the quality, consistency, and throughput achievable using our high throughput system. The Annual Merit Review showcases DOE funded research in the fields of hydrogen, fuel cells, and vehicle technologies.

PCT Awarded NAVY SBIR Phase I for "Long Lasting, Highly Efficient, and Safe Batteries for Sensor Systems"

June 2015 - Pneumaticoat Technologies has been awarded a DOD Phase I SBIR from the Navy to develop improved batteries for sensor systems. This work will focus on improving the overall safety of the battery systems and improving the lifetime performance of critical, battery operated, sensors. Picoshield® coatings will play a crucial role in improving battery performance.

More informsation can be found here: http://www.pneumaticoat.com/news.html 

 

By incorporating well established manufacturing principles (continuous vs. batch, variable throughput vs. fixed throughput, etc.), PneumatiCoat Technologies has developed an efficient and cheap process for precise coating of powders, flats, and objects. Thanks to our innovative process design and system building know-how, Pneumaticoat Technologies is pushing the boundaries of ALD for manufacturing. With our technology, the days of ALD being too slow and too expensive are over. With high throughput manufacturing capabilities, at inexpensive price points, a great majority of the application technologies that were "put on the shelf" can now be reconsidered as viable commercial products. Combined with the exponential growth in application R&D, PneumatiCoat Technologies' systems are well-poised to help usher in a new wave of customized products to market. (http://www.pneumaticoat.com)

KAUST demonstrate ALD Passivation to stop Degradation of Nanorod Anodes in Lithium Ion Batteries

Researchers at King Abdullah University of Science and Technology (KAUST) demonstrate an effective strategy to overcome the degradation of MoO3 nanorod anodes in lithium (Li) ion batteries at high-rate cycling, which is achieved by conformal nanoscale surface passivation of the MoO3 nanorods by HfO2 using atomic layer deposition (ALD). The nanoscale HfO₂ layer was deposited on the prepared electrodes at 180 °C using atomic layer deposition system (Ultratech/Cambridge Nanotech Savannah).

 

 

Surface Passivation of MoO3 Nanorods by Atomic Layer Deposition toward High Rate Durable Li Ion Battery Anodes

B. Ahmed, Muhammad Shahid, D. H. Nagaraju , D. H. Anjum , Mohamed N. Hedhili, and H. N. Alshareef
Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955−6900, Saudi Arabia
ACS Appl. Mater. Interfaces, Article ASAP
DOI: 10.1021/acsami.5b03395
Publication Date (Web): June 3, 2015

 

We demonstrate an effective strategy to overcome the degradation of MoO3 nanorod anodes in lithium (Li) ion batteries at high-rate cycling. This is achieved by conformal nanoscale surface passivation of the MoO3 nanorods by HfO2 using atomic layer deposition (ALD). At high current density such as 1500 mA/g, the specific capacity of HfO2-coated MoO3 electrodes is 68% higher than that of bare MoO3 electrodes after 50 charge/discharge cycles. After 50 charge/discharge cycles, HfO2-coated MoO3 electrodes exhibited specific capacity of 657 mAh/g; on the other hand, bare MoO3 showed only 460 mAh/g. Furthermore, we observed that HfO2-coated MoO3 electrodes tend to stabilize faster than bare MoO3 electrodes because nanoscale HfO2 layer prevents structural degradation of MoO3 nanorods. Additionally, the growth temperature of MoO3 nanorods and the effect of HfO2 layer thickness was studied and found to be important parameters for optimum battery performance. The growth temperature defines the microstructural features and HfO2 layer thickness defines the diffusion coefficient of Li-ions through the passivation layer to the active material. Furthermore, ex situ high resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and X-ray diffraction were carried out to explain the capacity retention mechanism after HfO2 coating.

Next-Generation Lithium Metal Anode Engineering by Atomic Layer Deposition

Researchers at University of Maryland demonstrate Al2O3 ALD of protection layers directly on Li metal that protect the Li surface from corrosion due to atmosphere, sulfur, and electrolyte exposure. Lithium metal is considered to be the most promising anode for next-generation batteries due to its high energy density of 3840 mAh g–1. Major obstacles for lithium metal anodes is that the Li surface is highly reactive which can lead to reactions with the solvents and the electrolyte and contamination, reducing the performance of batteries employing Li metal anodes. 

Next-Generation Lithium Metal Anode Engineering via Atomic Layer Deposition 

Alexander C. Kozen, Chuan-Fu Lin, Alexander J. Pearse, Marshall A. Schroeder, Xiaogang Han, Liangbing Hu, Sang-Bok Lee, Gary W. Rubloff, and Malachi Noked

ACS Nano, Article ASAP DOI: 10.1021/acsnano.5b02166 Publication Date (Web): May 13, 2015

Lithium metal is considered to be the most promising anode for next-generation batteries due to its high energy density of 3840 mAh g–1. However, the extreme reactivity of the Li surface can induce parasitic reactions with solvents, contamination, and shuttled active species in the electrolyte, reducing the performance of batteries employing Li metal anodes. One promising solution to this issue is application of thin chemical protection layers to the Li metal surface. Using a custom-made ultrahigh vacuum integrated deposition and characterization system, we demonstrate atomic layer deposition (ALD) of protection layers directly on Li metal with exquisite thickness control. We demonstrate as a proof-of-concept that a 14 nm thick ALD Al2O3 layer can protect the Li surface from corrosion due to atmosphere, sulfur, and electrolyte exposure. Using Li–S battery cells as a test system, we demonstrate an improved capacity retention using ALD-protected anodes over cells assembled with bare Li metal anodes for up to 100 cycles.

ALD protected Lithium Metal Anodes with improved capacity retention

University of Maryland demonstrate atomic layer deposition (ALD) of protection layers directly on Li metal with exquisite thickness control. They show that 14 nm thick, ALD Al2O3 layer can protect the Li surface from corrosion due to atmosphere, sulfur, and electrolyte exposure. Using Li-S battery cells as a test system, an improved capacity retention using ALD protected anodes over cells assembled with bare Li metal anodes for up to 100 cycles was shown.

Next-Generation Lithium Metal Anode Engineering via Atomic Layer Deposition

Alexander C Kozen, Chuan-Fu Lin, Alexander J Pearse, Marshall A Schroeder, Xiaogang Han, Liangbing Hu, Sang Bok Lee, Gary W. Rubloff, and Malachi Noked

ACS Nano, Just Accepted Manuscript

DOI: 10.1021/acsnano.5b02166

Publication Date (Web): May 13, 2015

Lithium metal is considered the most promising anode for next-generation batteries due to its high energy density of 3840 mAhg-1. However, the extreme reactivity of the Li surface can induce parasitic reactions with solvents, contamination, and shuttled active species in the electrolyte, reducing performance of batteries employing Li metal anodes. One promising solution to this issue is application of thin chemical protection layers to the Li metal surface. Using a custom made ultrahigh vacuum (UHV) integrated deposition and characterization system, we demonstrate atomic layer deposition (ALD) of protection layers directly on Li metal with exquisite thickness control. We demonstrate as a proof of concept that a 14 nm thick, ALD Al2O3 layer can protect the Li surface from corrosion due to atmosphere, sulfur, and electrolyte exposure. Using Li-S battery cells as a test system, we demonstrate an improved capacity retention using ALD protected anodes over cells assembled with bare Li metal anodes for up to 100 cycles.

Amorphous ALD iron phosphate buffers high capacities at high current densities in Litthium Ion Batteries

Researchers at University of Western Ontario, Canada, shows that by coating LiNi_0.5Mn_1.5O₄ cathode material powders with ultrathin amorphous FePO₄ by ALD it is possible to dramatically increase the capacity retention of LiNi_0.5Mn_1.5O₄. The researchers believe that the amorphous FePO₄ layer acts as a lithium-ions reservoir and electrochemically active buffer layer during the charge/discharge cycling, helping achieve high capacities in LiNi_0.5Mn_1.5O₄, especially at high current densities. 

The ALD amorphous FePO₄ was deposited using ferrocene (FeCp₂), ozone, trimethyl phosphate (TMPO), and water (H₂O) in an Ultratech/Cambridge Nanotech Savannah 100 ALD system. 

Please check out all the details in the Open Access article below:

Unravelling the Role of Electrochemically Active FePO4 Coating by Atomic Layer Deposition for Increased High-Voltage Stability of LiNi0.5Mn1.5O4 Cathode Material [OPEN ACCESS] 
Biwei Xiao1, Jian Liu1, Qian Sun1, Biqiong Wang1,2, Mohammad Norouzi Banis1, Dong Zhao2, Zhiqiang Wang2, Ruying Li1, Xiaoyu Cui3, Tsun-Kong Sham2 and Xueliang Sun1,*
Article first published online: 25 MAR 2015, DOI: 10.1002/advs.201500022

Ultrathin amorphous FePO4 coating derived by atomic layer deposition (ALD) is used to coat the 5 V LiNi0.5Mn1.5O4 cathode material powders, which dramatically increases the capacity retention of LiNi0.5Mn1.5O4. It is believed that the amorphous FePO4 layer could act as a lithium-ions reservoir and electrochemically active buffer layer during the charge/discharge cycling, helping achieve high capacities in LiNi0.5Mn1.5O4, especially at high current densities.

Schematic illustrations of a) LNMO-n upon cycling; b) illustration of the electrolyte highest occupied molecular orbital (HOMO) and work functions of FePO₄ and LiNi_0.5Mn_1.5O₄.

FESEM images of a) LNMO-0 and b) LNMO-20; c) HRTEM images of LNMO-20 (inset: Electron diffraction patterns of the LNMO-20 along the [110] zone axis).

Observation of Nanoscale Processes in Lithium Batteries

Observation and Quantification of Nanoscale Processes in Lithium Batteries by Operando Electrochemical (S)TEM

B. L. Mehdi, J. Qian, E. Nasybulin, C. Park, D. A. Welch, R. Faller, H. Mehta, W. A. Henderson, W. Xu, C. M. Wang, J. E. Evans, J. Liu, J. -G. Zhang, K. T. Mueller, and N. D. Browning
Nano Lett., 2015, 15 (3), pp 2168–2173

 

An operando electrochemical stage for the transmission electron microscope has been configured to form a “Li battery” that is used to quantify the electrochemical processes that occur at the anode during charge/discharge cycling. Of particular importance for these observations is the identification of an image contrast reversal that originates from solid Li being less dense than the surrounding liquid electrolyte and electrode surface. This contrast allows Li to be identified from Li-containing compounds that make up the solid-electrolyte interphase (SEI) layer. By correlating images showing the sequence of Li electrodeposition and the evolution of the SEI layer with simultaneously acquired and calibrated cyclic voltammograms, electrodeposition, and electrolyte breakdown processes can be quantified directly on the nanoscale. This approach opens up intriguing new possibilities to rapidly visualize and test the electrochemical performance of a wide range of electrode/electrolyte combinations for next generation battery systems.

Chemists boost carbon's stability of lithium-air batteries by ALD

CHESTNUT HILL, MA (February 25, 2015) - To power a car so it can travel hundreds of miles at a time, lithium-ion batteries of the future are going to have to hold more energy without growing too big in size.

That's one of the dilemmas confronting efforts to power cars through re-chargeable battery technologies. In order to hold enough energy to enable a car trip of 300-500 miles before re-charging, current lithium-ion batteries become too big or too expensive.

Chemists from Boston College and UMass Amherst applied two nano-scale coatings to a unique form of carbon, known as 3DOm. The resulting boost in 3DOm's stability produced performance gains that could lead to the material's use in lithium-air batteries. (Image : Boston College)

In the search for the "post-lithium-ion" battery, Associate Professor of Chemistry Dunwei Wang has been developing materials that might one day enable the manufacture of new batteries capable of meeting power demands within the size and cost constraints of car makers and other industries.

In a recent report published in the German journal Angewandt Chemie (Abstract below), Wang and a colleague from the University of Massachusetts Amherst unveiled a new method of stabilizing carbon - a central structural component of any battery - that could pave the way to new performance standards in the hunt for a lithium-ion components.

Central to the search for improved performance is the ability to shed weight and costly chemical components. Researchers pursuing a "lithium-air" battery have focused on a chemical reaction of lithium and oxygen, which can be pulled from the air. But the materials used to generate this reaction have shown poor life cycles, lasting through just a few charges.

Boston College chemist Dunwei Wang

The culprit, said Wang, is the instability of carbon, an essential structural support to a battery's electrode, a conductor where charges collect and dispense.

"Carbon is used in every battery because it has that combination of low cost, light weight and conductivity," said Wang. "You can't just scrap it."

So Wang and UMass Assistant Professor of Chemical Engineering Wei Fan set to work improving the performance capabilities of a newly engineered form of carbon fabricated by Fan. It's called three-dimensionally ordered mesoporous (3DOm) carbon and scientists value it for its highly ordered structure.

Employing a technique called atomic layer deposition (ALD), the researchers grew a thin coating of iron oxide on the carbon, a step that enhanced the reactivity between lithium and oxygen and improved performance on the charge cycle. Next, they used ALD to apply a coating of palladium nanoparticles, which effectively reduced carbon's deteriorative reaction with oxygen and improved the discharge cycle.

Their initial tests on the material showed marked improvement in performance. "We demonstrated that a particular form of carbon can be used to support a new type of chemistry that allows for energy storage with the promise of five to 10 times more energy density than state-of-the-art lithium-ion batteries we see today," said Wang. "We see this as significantly improving the cyclability of the battery, which is a key issue."

Wang said the findings show 3DOm carbon can meet new performance standards when it is stabilized.

"The key innovation we make here is that 3DOm carbon is stable - we have stabilized something that was not previously stable," said Wang.

Three Dimensionally Ordered Mesoporous Carbon as a Stable, High-Performance Li–O2 Battery Cathode
Jin Xie, Xiahui Yao, Qingmei Cheng, Ian P. Madden, Paul Dornath, Chun-Chih Chang, Prof. Dr. Wei Fan, Prof. Dr. Dunwei Wang

Article first published online: 10 FEB 2015
DOI: 10.1002/ange.201410786
Enabled by the reversible conversion between Li₂O₂ and O₂, Li–O₂ batteries promise theoretical gravimetric capacities significantly greater than Li-ion batteries. The poor cycling performance, however, has greatly hindered the development of this technology. At the heart of the problem is the reactivity exhibited by the carbon cathode support under cell operation conditions. One strategy is to conceal the carbon surface from reactive intermediates. Herein, we show that long cyclability can be achieved on three dimensionally ordered mesoporous (3DOm) carbon by growing a thin layer of FeO_x using atomic layer deposition (ALD). 3DOm carbon distinguishes itself from other carbon materials with well-defined pore structures, providing a unique material to gain insight into processes key to the operations of Li–O₂ batteries. When decorated with Pd nanoparticle catalysts, the new cathode exhibits a capacity greater than 6000 mAh g_carbon⁻¹ and cyclability of more than 68 cycles.