Lithium Vanadium Phosphate

I noticed recent press releases from GS Yuasa describing its efforts in developing lithium vanadium phosphate cathode materials for next generation Li-ion applications. A good link to this may be found at the Green Car Congress website:

GS Yuasa Prototypes Li-ion Batteries with Vanadium Phosphate Cathode Material

Nothing is disclosed by GS Yuasa about the precise chemical nature of this vanadium phosphate active material. The best known phase in this area is the monoclinic Nasison phase, Li3V2(PO4)3. This material promises to deliver safe, large format Li-ion batteries with improved energy density and rate performance over LiFePO4. Clearly the use of this material in Li-ion applications has been covered in numerous issued patents assigned to Valence Technology Inc., so it will be interesting to find out more about the GS Yuasa chemistry.

It will be intriguing to see how this progresses.

Jerry

Li2FeP2O7: A Potential New Active Material for Lithium-ion Batteries?

A article in JACS by Nishimura and co-workers recently caught my eye. The paper describes the promising electrochemical lithium insertion characteristics of the lithium iron diphosphate material, Li2FeP2O7. The link to the paper may be found here:

New Lithium Iron Pyrophosphate as 3.5 V Class Cathode for Lithium Ion Battery

The iron diphosphate demonstrates a reversible specific capacity of around 110 mAh/g at an operating voltage of about 3.5 V vs Li. These are encouraging characteristcs and when combined with the anticipated low cost and good thermal safety, this cathode material may represent an excellent choice for incorporation into large format Li-ion devices. I guess it could even challenge LiFePO4 in some limited applications.

The Li2FeP2O7 material actually represents just one example of a class of lithium metal diphosphates, Li2MP2O7 (where M = Fe, Co, Ni, Mn etc.). The use and preparation of these materials was first recognized in the following issued US patent (Inventors: Barker and Saidi, filed April 2003):

US#7008566: Oligo Phosphate-based Electrode Active Materials

I will wait with great interest to see the developments in this field. Clearly some of the analog materials such as Li2MnP2O7 may offer improved electrochemical behavior over the Fe phase. Will it be possible to extract both lithium ions from the structure?

Jerry

Pellion Technologies Inc.

Pellion Technologies Inc., an MIT spin-out company researching new magnesium-based energy storage systems has recently launched its website:

Pellion Technologies Inc.

The company is an early-stage company developing an innovative energy storage solution with the potential to deliver substantially lower cost and higher energy density than current lithium ion systems. Pellion, based in the Boston, MA area, is backed by top-tier venture capital and a recent award from the U.S. Department of Energy to develop next-generation batteries.

Jerry

AMSO4F: Fluorosulfates - New Active Materials for Advanced Battery Applications

Alkali metal fluorosulfate materials (AMSO4F, A = Li or Na; M = transition metal in oxidation state +2) are currently receiving significant attention as potentially valuable cathode active materials for advanced battery applications. The lithium-based materials all possess the triclinic, tavorite structure - so are isostructural with the lithium vanadium fluorophosphate phase, LiVPO4F.

Of particular note are the iron and manganese phases, LiFeSO4F and LiMnSO4F, which may represent important and new electroactive materials for Li-ion batteries. These materials offer a theoretical specific capacity of around 150 mAh/g (assuming the reversible cycling of 1 Li ion per formula unit). The Fe analog operates at around 3.5-3.6 V vs. Li - meaning that it generates a specific energy comparable with LiFePO4. When combined with its superior electronic conductivity, this performance suggests that LiFeSO4F could challenge the iron olivine, LiFePO4 as a low-cost active material for future large format Li-ion battery applications.

The challenges ahead will no doubt involve the development of a inexpensive and scalable synthesis method. Recent publications and presentations at the IMLB-2010 conference in Montreal suggest that the preparative approach adopted will be of critical importance in determining the electrochemical performance.

The use of these materials in energy storage applications is covered in the following US Patent application (US 2005/0163699 - Inventors: Jerry Barker and co-workers; Assignee: Valence Technology Inc.). The link to this patent application may be found here:

Fluorosulfate-based electrode active materials and methods of making the same

It should also be stressed that earlier US patent and US patent applications (involving the same inventors) also exist.

Jerry

ARPA-E Program

Last month the U.S. Department of Energy announced it is awarding $106 million in federal funding through the Advanced Research Projects Agency – Energy (ARPA-E) for 37 ambitious research projects that could fundamentally change the way the US uses and produces energy. Within the Batteries for Electrical Energy Storage in Transportation (BEEST) sector there were some important awards.

The BEEST program seeks to create a portfolio of high-risk, high-reward R&D projects focused on developing ultra-high energy density, low cost battery technologies that is complimentary to the DOE Office of Vehicle Technologies’ (OVT) strong existing R&D portfolio in state-of-the-art Lithium-ion batteries. It is a high-risk, high reward strategy that will invest and support novel energy storage technologies.

More information on the objectives of BEEST may be found here:

The ARPA-E BEEST Program

Of particular interest to me are the awards given to Pellion Technologies Inc. and ReVolt Technology LLC.

Pellion Technologies is an MIT spin-out that will develop a low cost magnesium ion battery technology using high throughput computational methods in combination with accelerated material synthesis techniques.

ReVolt Technology will develop a novel large format Zn-air battery concept based on a closed loop system in which the zinc anode is suspended as a slurry within a storage tank.

Further information on these concepts and the other ARPA-E projects may be found here:

APRA-E - Recovery Act Funding

This blog will keep you posted on key developments within the ARPA-E program.

Jerry

New LiVPO4F Paper: Confirms Excellent Li-ion Performance

A recent publication by M.V. Reddy and co-workers (NSU, Singapore) has confirmed the outstanding lithium insertion behavior of the lithium vanadium fluorophosphate phase, LiVPO4F.

The abstract for this study may be found here:

Long-term cycling studies on 4V cathode, lithium vanadium fluorophosphate

In particular, the long term cycle life (1260 cycles) and associated low capacity fade behavior indicate the acceptability of the LiVPO4F material for next generation Li-ion batteries. When this electrochemical performance is considered in combination with its outstanding thermal stability (see entry below - ARC measurements on the charged, de-lithiated LiVPO4F material by Jeff Dahn's group) it suggests strongly that this material could replace current cathode technology to enable the commercial production of low cost, high energy density and safe Li -ion batteries for next generation applications (for example, EV and PHEV).

In addition, the rate perforamnce indicates that LiVPO4F may alos be a candidate cathode material for high rate Li applications.

Jerry

Surion Energy Limited

Surion Energy - a new company developing electrode materials for next generation Li-ion batteries - has recently launched its new website. A link to the Surion site may be found here:

Surion Energy Limited

Surion Energy is located at the Culham Science Centre, close to Oxford in the UK. The company is attempting to exploit its proprietary Li2FeS2 cathode technology to meet the growing demand for large format Li-ion batteries for electric vehicle applications.

Jerry

IMLB-2010

Jerry will be presenting at the up-coming 15th International Meeting on Lithium Batteries (IMLB-2010) to be held in Montreal, Canada during June 27 and July 2.

More information on this important conference may be found here:

15th International Meeting on Lithium Batteries (IMLB-2010)

Jerry

Li-ion Rechargeable Batteries: Novel Materials

The review article entitled 'Lithium-ion Rechargeable Batteries: Novel Materials' by Jerry Barker has now been published in the 'Encyclopedia of Materials: Science and Technology' (Elsevier, January 2010). The review gives an overview and summary of the present status of anode and cathode materials.

The abstract for the article may be found here:

Lithium-ion Rechargeable Batteries: Novel Materials

The encyclopedia contains several other articles in the energy storage sector that you may find useful.

Jerry

Li2FePO4F - A Fluorophosphate active material for Li-ion Applications

Following on from our previous discussions regarding the LiMPO4F (M = Fe, Mn, V, Cr etc.) and Li2MPO4F (M = Fe, Mn, Co, Ni etc.) active materials for Li-ion applications, a recent paper by Linda Nazar et al. describes the electrochemistry of the LiFePO4F- Li2FePO4F insertion system. The abstract to this manuscript may be found here:

Tavorite Lithium Iron Fluorophosphate Cathode Materials, ESL 13, A43, 2010

The use of these materials in Li-ion batteries is covered in several US patents and patent applications (inventors J. Barker and co-workers).

Jerry