Green Patent Blog

The ink had barely dried on Paice LLC’s (Paice) new hybrid vehicle patent when the Florida-based hybrid technology company once again accused Toyota of infringement.  U.S. Patent No. 7,392,871 (’871 patent) issued on July 1st, and Paice filed suit the same day in federal court in Marshall, Texas.

The bare bones complaint (paicecomplaint.pdf) alleges that Toyota directly infringes the ‘871 patent by making and selling the Highlander hybrid SUV and the Lexus RX400h hybrid SUV and that the carmaker induces and contributes to infringement by encouraging others to operate the vehicles.  The complaint asks the court for an injunction, compensatory damages, treble damages for willful infringement and an award of attorney fees.

The ‘871 patent is the latest in a family of patents that cover improvements upon Paice’s U.S. Patent No. 5,343,970 (’970 patent).  The ’871 patent claims a hybrid vehicle having three AC electric motors each with an AC-DC converter. 

The patent explains that providing three motors (one is a starting motor, the other two are traction motors) conveys mechanical and efficiency advantages such as eliminating the need for a fore-and-aft driveshaft and allowing traction control to be centrally accomplished by a microprocessor.

Paice’s assertion of the ‘871 patent opens a new front in a series of battles with Toyota.  Two prior lawsuits involved the ‘970 patent.

In one of those suits, the Prius and other Toyota hybrids were found to infringe and Paice was awarded $4.3 million in damages.  (see my previous posts on that case here, here and here).  Toyota tried to appeal all the way to the Supreme Court, but the Supremes refused to hear the case.  Another suit, also in the Eastern District of Texas, is pending.

In a recent post, I wrote about one of A123 Systems’ (A123) new products - the Hymotion Plug-in Conversion Module, which can convert the Toyota Prius into a plug-in electric vehicle and boost its mpg to over 100 for the first 30-40 miles of driving.

Last month saw more good news for the Boston area battery maker.  First, the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) announced that it had signed a three-year deal with A123 to support the company’s efforts to develop more powerful and longer lasting batteries for hybrid-electric vehicles.

Under the Cooperative Research and Development Agreement, NREL and A123 will research new techniques for improving thermal management in transportation batteries.

A123 also got a boost for a different application of its battery technology - using batteries to get more power out of the electric grid.  CNET recently reported that some electric utilities (unnamed for now) have made a deal with A123 to use its lithium ion batteries to help stabilize the grid (see the greentech media story).

Several of A123’s patents and applications, including U.S. Patent No. 7,348,101, U.S. Patent No. 7,261,979 and U.S. Application Pub. No. 2007/0166617, cover various aspects of lithium ion battery technology.   A123’s patented battery technology reduces the amount of time necessary for charging and loses relatively little capacity and power over numerous charge/discharge cycles. 

The continuing good news for A123 indicates that the company is widely viewed as a winner.  Significantly for A123, it also demonstrates the versatility of its technology for use in a variety of applications.

Battery maker A123 Systems (A123) just started selling its L5 Hymotion Plug-in Conversion Modules, which can transform the Toyota Prius into a plug-in vehicle capable of getting up to 100 mpg for the first 30-40 miles of driving.  The L5’s high energy capacity lithium ion batteries supplement the vehicle’s battery and allow the Prius to use its electric drive more often and for longer distances.  More frequent periods of all electric driving translate into better fuel efficiency. (read the Ecogeek piece and green tech gazette article on the L5)

A123 calls the Hymotion technology Nanophosphate, which means the batteries use lithium iron phosphate as cathode material.  Several of A123’s patents and applications cover lithium iron phosphate batteries, including U.S. Patent No. 7,348,101, U.S. Patent No. 7,261,979 and U.S. Application Pub. No. 2007/0166617. 

A123’s patented battery technology reduces the amount of time necessary for charging and loses relatively little capacity and power over numerous charge/discharge cycles, an important advantage for applications that need high power for long periods of time, such as motor vehicles.  Specifically, one problem with rechargeable batteries is that relatively high charge rates (i.e., less than half an hour) typically cause growth in impedance (resistance and voltage drop). 

Impedance can lead to lithium plating, a film formation on the surface of the negative electrode materials which consumes some of the active lithium from the battery and results in a loss of capacity.  The materials used by A123, including lithium iron phosphate, achieve low impedance growth.  The resulting batteries don’t have the problem of lithium plating and therefore maintain higher power capacities over time, enabling the highly efficient Prius to be even more efficient.

After losing three in a row to hybrid technology company Paice, first by jury verdict in the district court, then in the court of appeals and then being rejected by the Supremes, the Toyota Prius has finally prevailed in a patent infringement suit.  Earlier this month, the U.S. Court of Appeals for the Federal Circuit (the court that hears appeals of patent decisions from district courts and administrative agencies) held that Toyota did not infringe a patent owned by Connecticut hybrid technology company Solomon Technologies (Solomon).

Solomon’s U.S. Patent No. 5,067,932 (’932 patent) covers a combination motor and transmission device having a continuously variable speed of rotation.  According to the patent, the invention permits a hybrid engine to operate at peak power over a greater range of rotational speed, or rpm.

As is often the case in patent litigation, claim construction (the court’s interpretation of the legal scope of a patent’s claim language) was critical here.  The disputed language was in claim 7 of the ‘932 patent, which requires an “integral combination” of a motor element and a transmission unit element and requires that one of the two elements be located “within an envelope” containing the other element.

The Federal Circuit affirmed that the “integral combination” element means the motor and transmission are directly attached without the presence of shafts, bearings or other components in between.  Because Toyota’s transaxles have rotor shafts between the motor-generators and the transmission unit, the court found they did not infringe.

The court also held that the term “within an envelope” means that one of the two elements (motor or transmission unit) is within the imaginary space defined by the rotation of the other element.  As an additional basis for non-infringement, the Federal Circuit found that Toyota’s transmission gears were outside of the imaginary space defined by the motors’ magnet assemblies.

So the Prius is off the schneid in patent litigation, and the win comes as Toyota celebrates a happy milestone - the Prius went platinum this month, with over one million sold worldwide.

Last week, the U.S. Supreme Court denied Toyota’s petition for certiorari, refusing to review a lower court’s ruling that the Prius, Lexus RX400h and Highlander SUV hybrid cars infringe a patent owned by hybrid technology company Paice LLC. (read my previous post on Toyota’s appeal)  Toyota had argued that Paice’s statements in its patent that prior technology had “substantial deficiencies” and was ”compex and difficult to manufacture” precluded infringement under the doctrine of equivalents because Toyota’s hybrid vehicles used an aspect of that prior technology.  But the appeals court ruled that language in a patent criticizing a prior invention had to be clear as to which aspect of the invention is being criticized for a court to deny that the patent scope covers the prior invention as an equivalent.   

So the decision by the U.S. Court of Appeals for the Federal Circuit will stand.  In that decision, the Federal Circuit affirmed a $4.3 million jury verdict that Toyota’s hybrid drive trains infringed U.S. Patent No. 5,343,970 as an equivalent system but vacated the district court award of a $25 per vehicle ongoing royalty.  (read my previous post on the Federal Circuit decision) Now the case will go back to the trial court to determine the amount of ongoing royalty Toyota will have to pay Paice.

As is typical, the Supreme Court did not give a reason for its decision to deny review.  But the denial means that fewer than four justices favored review of the case (if four justices vote to review, the high court grants the petition for certiorari).  I remember one of my law professors used to describe his exams as consisting of big issues, little issues and non-issues and advised students to figure out which is which and not spend any time on the non-issues.  Here, Toyota tried to dress up a non-issue as a big issue, and the Supremes wisely declined to spend any time on it.