Altair Nanotechnologies Details Fast Charge Features of Its Nano Titanate Battery; Nano materials used to deliver fast charge capability also increase safety of battery
In anticipation of Altairnano's delivery of its first NanoSafe battery pack in September, this is the second of four planned news releases identifying features of Altairnano NanoSafe batteries that may prove advantageous in the power rechargeable battery market. The remaining two releases will discuss battery life and power capacity. On August 24, 2006 Altairnano detailed why its nano titanate battery technology delivers high battery safety. The combination of these features has the potential to make Altairnano's NanoSafe batteries ideal for power applications such as electric vehicles and hybrid electric vehicles.
How Does a Rechargeable Battery Work?
A battery consists of a positive electrode, a negative electrode, a porous separator that keeps the electrodes from touching, and an ionic electrolyte, which is the conducting medium for ions (charged particles) between the positive and the negative electrodes. When the battery is being charged, ions transfer from the positive to the negative electrodes via the electrolyte. On discharge these ions return to the positive electrode releasing energy in the process.
Existing Lithium Ion Batteries
Rechargeable lithium ion batteries currently use graphite for the negative electrode and typically lithium cobalt oxide for the positive electrode. The electrolyte is a lithium salt dissolved in an organic solvent which is flammable.
During charge, lithium ions deposit inside the graphite particles. However the rate at which lithium ions can deposit is limited by the electro-chemical properties of the graphite, and if they can not enter the graphite particles they, instead, may collect (plate) on the negative electrode's surface as lithium metal. This can occur if the ions are deposited too rapidly on the graphite electrode as might be the case if the battery is charged too quickly. If this plating occurs, the battery will severely degrade in performance and in extreme cases, will short, causing overheating and thermal runaway - a major fire hazard.
So the time to charge (charge rate) is restricted by the ion incorporation rate capability in lithium ion batteries, resulting in charge times measured in hours. Also, charge rate can be affected by external factors such as temperature. At low temperatures, the lithium ion incorporation rate is significantly less than at room temperature so charging at these temperatures may be much longer or impossible.
Given that the charge rate is governed by fundamental properties of the materials, the only option is to change the materials and chemistry of the battery.
The Altairnano NanoSafe(TM) Battery
Altairnano solved this problem by using an innovative approach to rechargeable battery chemistry by replacing graphite with a patented nano-titanate material as the negative electrode in its NanoSafe batteries. By using nano-titanate materials as the negative electrode material, lithium metal plating does not occur because the electro-chemical properties of the nano-titanate allow the deposition of lithium in the particles at high rates. These electrical properties mean that even at very cold temperatures there is no risk of plating. No undesirable interaction takes place with the electrolyte in the Altairnano batteries, which permits the battery to be charged very rapidly, without the risk of shorting or thermal runaway. In fact, in recent laboratory testing, Altairnano has demonstrated that a NanoSafe cell can be charged to over 80% charge capacity in about one minute. Actual charge rates achieved in specific applications will vary due to the application environment.
The same technology also increases battery discharge rates which could be important to applications that require bursts of power, for example, a freeway electric vehicle accelerating rapidly. The NanoSafe cell has demonstrated that surges of power can be delivered without risking thermal runaway or performance damage to the battery.
By using patented nano-titanate materials in the battery construction, Altairnano NanoSafe cells have displayed very fast charge and discharge rates and appear to offer a safer solution than conventional lithium ion batteries.
Altairnano is delivering its first NanoSafe battery pack in September to Phoenix Motorcars for incorporation into an electric vehicle. Phoenix Motorcars, based in Ojai, California, is an early leader in the effort to mass produce full function, freeway ready electric automobiles.
NanoSafe(TM) is a trademark of Altair Nanotechnologies Inc.
ABOUT ALTAIR NANOTECHNOLOGIES INC.
Altairnano is an innovator and supplier of advanced ceramic nanomaterials. With a skilled team of scientists in its 100,000 square foot facilities who, coupled in collaborative ventures with industry partners and leading academic centers, have developed a unique portfolio of intellectual property and novel products. These researchers are complemented by a seasoned management team with substantial experience in commercializing innovative, disruptive technologies.
Altairnano focuses on nanotechnology applications to enable new high-growth markets. In alternative energy Altairnano is pioneering new battery materials and systems. The company is applying nanotechnology to the development of drug candidates for humans and animals, coatings materials for implants, and materials for dental applications. Its high performance nanomaterials have applications in paints, coatings, and the treatment of water and air. The Altairnano Hydrochloride Pigment process, the first new patented pigment process in 50 years, is an environmentally friendly method for manufacturing white pigment used in paints, paper and plastic. For additional information visit www.altairnano.com.
This release may contain forward-looking statements as well as historical information. Forward-looking statements, which are included in accordance with the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995, may involve risks, uncertainties and other factors that may cause the company's actual results and performance in future periods to be materially different from any future results or performance suggested by the forward-looking statements in this release. These risks and uncertainties include, without limitation, the risk that NanoSafe batteries will perform differently in extended road tests or in actual usage than in laboratory tests and possibly exhibit charge and discharge rates that differ from those suggested by laboratory testing; that markets for potential products using NanoSafe batteries, many or which are small or non-existent, will not expand or come into existence as expected; that even if a significant market evolves, that competing products will capture a dominant market position; and that even if NanoSafe batteries capture significant market position, production and overheard costs may exceed associated revenue. In addition, other risks are identified in the company's most recent Annual Report on Form 10-Q, as filed with the SEC. Such forward-looking statements speak only as of the date of this release. The company expressly disclaims any obligation to update or revise any forward-looking statements found herein to reflect any changes in company expectations or results or any change in events.