The cathode and anode are in the form of electroactive sheets separated from each other by a membrane that is permeable to the electrolyte. One or more of the cathode and anode comprises two or more layers of carbon nanotubes, one of which layers includes electrochemically active nanoparticles and/or microparticles disposed therein or deposited on the nanotubes thereof. The majority of the carbon nanotubes in each of the layers are oriented generally parallel to the layers. Optionally, one or more of the layers includes an additional carbon material such as graphene, nanoparticulate diamond, microparticulate diamond, and a combination thereof.

Benefits

• Unique combination of diamond nanoparticles and other carbon materials 
• Improves the ability to remove heat efficiently from the battery system 

The Invention 

An ultra thin surface coating composed of metal oxides that, when applied to granular electrode materials on a large scale, promises to solve the structural instability of electrode materials and the resulting rapid fade of cell capacity at high voltages and high temperatures in lithium-ion batteries. 

Argonne’s innovation, a powder nanocoating technology using metal oxides, has the following features: 

• Gas-phase surface chemical reactions; 
• A layer of extremely uniform metal oxide ultrathin film on granular cathode materials with precisely controlled surface morphology: smooth, conformal, and pin-hole free so that the electrode degradation reactions in the battery can be suppressed; and 
• Film so ultra thin and precisely controlled in its thickness that the transfer of the charge across the electrode/electrolyte interface takes place with a very limited, or even a reduced, interface resistance. 

In developing a surface coating for the electrodes of lithium-ion batteries, Argonne scientists sought to satisfy two requirements simultaneously: 

• Create a uniform coating that will fully isolate electrodes from the electrolyte, and 
• Create an ultra thin film that will allow the lithium ion and electron to easily tunnel without a large increase in impedance. 

Conventional technologies have been unable to fulfill those requirements and have proved incapable of precisely controlling the coating film properties of film thickness and morphology. As a result, battery performance can be unstable.

Benefits 

The new powder coating technology provides: 

• Smooth fluidization of ultrafine powders via non-linear processing control; 
• Online, real-time monitoring of powder fluidization status and surface chemical reaction; 
• Well-controlled properties of the nanocoated film (conformity, thickness, and composition); and 
• A novel process that is scalable, less energy-intensive, and at a lower cost. 

Lithium-ion batteries made of these novel coated materials offer: 

• Isolation of electrode from electrolyte, creating greater structural stability and effectively enhancing capacity retention; 
• Greater stability; 
• Longer lifespan; 
• Higher energy/power densities; 
• Greater safety; and 
• Reduced cost and increased performance (figure 2) reliability. 

Applications and Industries 

• Hybrid electric vehicles 
• Solar cells 
• Ultracapacitors 
• Cosmetics 

Developmental Stage 

Proof of concept. Lab scale has been demonstrated; small pilot scale up is on schedule. 

The Invention 

Scientists at Argonne National Laboratory have developed a method for creating a new class of platinum multi-metallic catalysts that are not only compositionally stable but also exhibit an advantageous electronic structure with enhanced catalytic properties. 

Using this process, researchers created an alloy of platinum and one or more transition metals (such as cobalt, nickel, iron, titanium, chromium and others). Next, they modified the near surface layers by annealing, which induces formations known as nanosegregated surfaces. These surfaces vastly improve performance by overcoming kinetic limitations for the oxygen reduction reaction. The result is a catalyst particularly advantageous for use in polymer electrolyte fuel cells. 

In the energy industry, fuel cells are rapidly becoming an important component. However, the high cost of manufacturing the platinum catalyst—a required element in a fuel cell—makes fuel cells relatively non-competitive in the commercial world. So far, such catalysts have not been able to demonstrate the performance and life expectancy consistent with a fuel cell’s long-term operation. Argonne’s invention overcomes this limitation. 

Benefits 

• Enhanced catalytic properties that drive improved performance, 
• Greater stability 
• Greater cost-effectiveness 

Applications and Industries 

• Polymer electrolyte membrane fuel cells 
• Energy storage devices, such as metal-air batteries 
• Magnetic storage devices 
• Automotive industry 

Developmental Stage 

Proof of concept 

• Method to compensate anode for initial irreversible capacity loss 
• Enables lithium- deficient cathode materials through lithium source 

An as-prepared cathode for a secondary battery, the cathode including an alkaline source material including an alkali metal oxide, an alkali metal sulfide, an alkali metal salt, or a combination of any two or more thereof.

The Invention 

A process that includes suspending/dissolving an electro-active material and a carbon precursor in a solvent; and then depositing the carbon precursor on the electro-active material to form a carbon-coated electro-active material. 

The method avoids the high temperature, pressure and manufacturing extremes of conventional chemical vapor deposition and other pyrolysis methods of preparation. When carbon-coated metal oxides (for electro-active materials) are prepared, the metal oxide often reduces to the metal species. Argonne’s method can produce carbon-coated metal oxides without the problems associated with reductions. The carbon precursor can be graphene, graphene oxide, carbon nanotubes, their derivatives or a combination of any two or more such carbon precursors. 

Benefits 

• Carbon-coated materials can be charged and discharged faster than non-coated materials. 
• Using this method, the metal oxide will not reduce to the metal species when coated with carbon. 
• Carbon-coated cathode materials have improved electronic conductivity. 
• With its high capacity and high current rate, carbon-coated materials are ideal for use in lithium batteries for plug-in and electric vehicles. 

Applications and Industries 

Coatings for electrodes used in batteries for 

• Electric and plug-in hybrid electric vehicles; 
• Portable electronic devices; 
• Medical devices; and 
• Space, aeronautical, and defense-related devices. 

Developmental Stage 

Proof of concept 

The Invention 

Two processes are provided. In the first process, an electro-active material is heated and exposed to a reducing gas to form a surface-treatment layer on the electro-active material. The reducing gas comprises hydrogen, carbon monoxide, carbon dioxide, an alkane, an alkyne, or an alkene. The process also includes introducing an inert gas with the reducing gas. The surface-treated, electro-active material may be used in a variety of applications such as in a rechargeable lithium battery. 

The second process includes mixing an electro-active material and a reducing agent to form a surface treatment layer on the electro-active material; and then removing the reducing agent. Removal includes vacuuming, filtering, or heating. The reducing agent is hydrazine, NaH, NaBH₄, LiH, LiAlH₄, CaH₂, oxalic acid, formic acid, diisobutylaluminium hydride, zinc amalgam, diborane, a sulfites, dithiothreitol, or Sn/HCl, Fe/HCl. The partially reduced electro-active material can be used in a variety of applications such as a rechargeable lithium battery, a primary lithium battery, or a secondary lithium battery. 

Benefits 

Increased electrical conductivity of cathode materials, which improves the rate capability of the material. By this process the battery can be charged or discharged faster without losing its electrochemical performance. 

Applications and Industries 

Coatings for electrodes used in batteries for 

• Electric and plug-in hybrid electric vehicles; 
• Portable electronic devices; 
• Medical devices; and 
• Space, aeronautical, and defense-related devices. 

Developmental Stage 

Proof of concept 

The Invention 

A process to modify the surface of the active material used in an electrochemical device. The modification agent can be a silane, organometallic compound, or a mixture of two or more of such compounds. Both negative and positive electrodes for lithium-ion batteries can be made from the surface-modified active materials. Surface modification can be accomplished by either adding the agent to a non-aqueous electrolyte used in constructing a battery, or by treating the materials in a gas phase or in a solution. 

Benefits 

• Increased safety and life of lithium-ion batteries, as the surface modification prevents a catalytic reaction in lithium-ion cells that generates hydrogen gas, which can lead to substantial power fade of the cell and potential explosions. 
• Includes methods and molecules as additives that enable electrode modification.

Applications and Industries 

Coatings for electrodes used in batteries for 

• Electric and plug-in hybrid electric vehicles; 
• Portable electronic devices; 
• Medical devices; and 
• Space, aeronautical, and defense-related devices.

Developmental Stage 

Reduced to practice