I recently learned of a compelling instance of U.S. government-funded clean tech research translating into widely commercialized technology through green patent licensing.

Argonne National Laboratory announced last month that LG Chem and General Motors had completed licensing agreements to use Argonne’s patented composite cathode material in the lithium-ion batteries that power the Chevy Volt (see the press release about the Argonne-LG Chem agreement here and the press release about the Argonne-GM agreement here).

Though perhaps old news, as pointed out in this Ceramic Tech Today piece, it still points up the power of green patent licensing and strategic tech transfer.

The licensed technology stemmed from early lithium-ion battery research funded by the U.S. Department of Energy’s (DOE) Office of Basic Energy Sciences in the late 1990s and subsequent development supported by DOE’s Office of Energy Efficiency and Renewable Energy. 

The technology relates to a two component layered composite structure used as material for a cathode, the positively charged part of a battery. 

A lithium-ion battery has a cathode and a negatively charged anode.  When the battery is fully charged, all of the lithium ions are in the anode.  When the battery is in use, the lithium ions flow from the anode through a thin membrane to react with the cathode, thereby creating an electrical current.

The new cathode materials are rich in manganese and provide increased stability through a layered composite structure with one component for energy storage and another component to stabilize the structure.  The material also yields high charge-storage capacities and is cheaper to produce because manganese is a relatively cheap raw material.

The cathode technology is protected by a family of patents issued between 2004 and 2008, including U.S. Patents Nos. 6,677,082 (’082 Patent), 6,680,143, 7,135,252, and 7,468,223. 

According to the ’082 Patent, a major problem of layered lithium electrode compounds is that the transition metal cations commonly used tend to suffer from structural instability and chemical degradation.

The’082 Patent describes its solution this way:

This invention addresses the stability of LiMO₂ electrode structures [where M is a trivalent transition metal cation], particularly LiMnO₂, and makes use of a Li₂M’O₃ component to improve stability.

According to an Argonne press release, the patented cathode technology is now mass produced in the battery of the Chevy Volt.

Argonne’s director, Eric Isaacs, said the “licensing agreement with LG Chem concretely illustrates the key role that DOE national laboratories like Argonne play in the manufacturing supply chain in the United States.”

More than that, this story demonstrates the confluence of funding, research, IP, and commercial risk-taking that is necessary to bring new clean technologies to market.

Electrovaya is an Ontario, Canada company that makes advanced batteries and battery systems.

Last month Electrovaya announced that it was selected by Chrysler as the battery supplier for the carmaker’s Ram plug-in hybrid electric vehicle demonstration program.  The Ram PHEV will use Electrovaya’s 12kWh lithium ion battery.

One of Electrovaya’s major innovations is its SuperPolymer brand battery technology, which the company’s web site calls “a novel nanostructured lithium ion polymer technology platform.”  This technology provides faster, more efficient transport of lithium, and therefore greater energy density, according to Electrovaya.

According to Electrovaya’s web site, the company has over 150 patents and pending applications worldwide.  One key patent is U.S. Patent No. 7,588,862 (’862 Patent), which relates to the polymer technology.

The ’862 Patent is entitled “Composite polymer electrolytes for a rechargeable lithium battery” and is directed to a composite electrolyte for use in thin plate rechargeable lithium batteries.  The electrolyte may be a solid laminate or a separator sheet to act as a barrier between the positive and negative electrodes of the battery.

A separator embodiment comprises an inert porous or micro-porous polymer laminate (12) coated with a polymer coating (14) containing a dissociable lithium compound.  The polymer coating is on the exposed surface of the laminate (12) and, during the coating process, partially flows into some of the pores (15) of the laminate (12). 

The separator could have just one face of the laminate (12) coated with the second polymer (14), as shown here, or could have both faces coated. 

The portion of unfilled pores (15) can be filled with a desired lithium salt containing organic solution (16).  Electrodes (18, 18′) are in contact with the separator laminate (12).  Current collectors (20, 20′) are located on the external surfaces of electrodes (18, 18′).

According to the ’862 Patent, existing solid polymer electrolyte laminates had higher concentrations of dissociable lithium ions, but they frequently had low mechanical strength. 

The patented electrolyte boosts a battery’s energy density by increasing the concentration of dissociable lithium ions per unit volume in the electrolyte while maintaining the mechanical strength of the laminate:

It has now been found that the amount of dissociable lithium ions can be increased without increasing the thickness of the electrolyte, and simultaneously providing desirable mechanical strength and integrity…

Eamex Corp. (Eamex) is a Japanese company that has developed a high energy density capacitor using a proprietary polymeric actuator with metal plating that serves as an electrode.

The capacitor and methods of making it are covered by U.S. Patent No. 7,169,822 (’822 patent).  The ’822 patent is directed to a polymeric actuator (1) comprising an ion-exchange resin (2) in the form of a flat plate or film and metal electrodes (3a, 3b) attached to the surface of the resin by chemical plating techniques.

Lead wires (4a, 4b) provide an electrical connection between the electrodes (3a, 3b) and a power source (5).  The metal electrodes (3a, 3b) are insulated from each other, and application of a potential difference between the electrodes causes the ion-exchange resin product to bend or deform.

According to Eamex’s web site and this Greentech Media article, the electrodes of the patented actuator have greatly increased surface area, and the energy density per unit volume reaches up to 600 Wh/L, which is equivalent to that of a lithium-ion secondary battery.

Reticle, Inc. (Reticle) is a Los Altos, California startup that has developed a new carbon electrode material and process of making the material, which is ideal for use in ultracapacitors (see New Energy and Fuel article here).  

Ultracapacitors are used to store energy in applications that require storage of large amounts of energy and rapid energy discharge, such as electric vehicles. 

Ultracapacitors store energy through movement of electrons, i.e., separation of charged species as positive ions called cations migrate to a negatively charged electrode (anode), and negative ions called anions move to a cathode, or positively charged electrode.  The more ions that are attracted to their respective electrodes, the more energy the ultracapcitor stores.

There are two known ways to increase the number of ions attracted – boosting voltage and increasing the surface area of the electrodes.  This is where Reticle comes in.  The company’s patented process produces electrodes from granular activated carbon which have much greater surface area than any known electrode materials presently offered (see the inventor’s cogent explanation here).

Whereas typical processes consolidate carbon by pressing it into thin films, Reticle’s process applies pressure to the carbon material from all sides and obviates the need to add binders or adhesives.  This allows for better automation than other capacitor material, so the material can be machined into any size with lots of conductive surface area.

This picture shows one unique aspect of the resulting material, which the company calls “Reticle Carbon”:

That is, not only is the surface area greater, but all of the carbon particles remain connected to ensure that all the charge is distributed across the entire surface area of the material.

This table compares the specs and capabilities of two Reticle capacitors with those of a couple of other commercially available products:

Reticle Carbon also is a good material for desalination applications because the higher mass and surface area allows the acquisition of more ions before a regeneration step would be required.

Reticle’s manufacturing process and resulting carbon material are protected by a family of four U.S. patents:  U.S. Patent Nos. 6,350,520 (claims granular active carbon material made by a high temperature and pressure process), 6,511,645 (claims a process for producing carbon material by consolidating amorphous carbon using elevated temperature compression), 6,544,648 (claims a processed carbon material consolidated under elevated temperature and pressure) and 6,787,235 (claims a processed carbon material consolidated in a hot isostatic press under elevated temperature and pressure).

According to Jack Mastbrook, who does marketing development for Reticle, the company is currently seeking funding to ramp up operations.  But Mastbrook told me that Reticle already has a deal in place to sell its activated carbon to a major consumer products manufacturer, which plans to test the material as a replacement for batteries in its products.