NiMH revival: Second best approaches often win
A PLAN B FOR BATTERIES.
September 8, 2007 – Vol.12 No. 24
green-energy-news.com
In life it’s always good to have a back-up plan, an alternative course of action in case the primary one goes sour.
The same could be said for developing batteries.
Leading the race in high-tech battery technology are variations of lithium ion. Lithium is the lightest solid element on the planet and is suitable for battery making. Yet lithium’s drawback for use in batteries is its global rarity. Unless more is found, or if dramatically less is needed per battery or if the chemistry gets significantly more powerful, its rarity may eventually limit its use for electric and hybrid electric vehicles. Rare elements on the planet are generally the most expensive.
Without a breakthrough in lithium technology, a Plan B, a back-up battery technology is needed, and soon.
The next best battery technology currently available is clearly nickel metal hydride (NiMH). It’s been proven in a wide range of products ranging from power tools to hybrid cars. All the currently available hybrids have a NiMH battery pack. Toyota has already said its next generation Prius will stick with the now time-tested technology. For Toyota the back-up plan is NiMH.
The NiMH technology has been improving and costs dropping. One significant improvement comes from a company known as Nilar. Nilar has apparently improved upon NiMH technology by taking the relatively basic step of stacking the battery cells horizontally like a stack of pancakes, as opposed to vertically like slices of bread in a pop-up toaster.
According to the company, the Nilar Membrane battery uses an electrically conductive membrane between the cells acting as a cell wall and the electrical connection. The anode of one cell contacts one side of the membrane and the cathode of the adjacent cell contacts the other side. This results in negligible transportation resistance of current between the cells, and uniform voltage across the entire electrode.
In batteries the connection between cells in series builds the voltage. The surface area of the cells contributes to the amount of available current or amperage.
The company uses Philips' time-tested Nickel Metal Hydride chemistry and says that its product should survive 2000 deep recharging cycles and 300,000 shallow ones. A Nilar battery pack should last the life of the vehicle, the company says.
Nilar is set to demonstrate that its battery is ready for prime time and will see it used in a live, real time, in front of real people, conversion of a stock Toyota Prius to a plug-in Prius. The live conversion will take place September 19th and 20th in Boston, Massachusetts at TechMash 2007 as part of its Embedded Systems Conference.
The California Cars Initiative (CalCars) says that drivers don’t have to wait for plug-in hybrids to be available in a few years from the major manufacturers. They can convert their cars now if they want and CalCars and team will show them how, using the Nilar battery at the conference.
Nilar was founded in 2000 and has facilities in Stockholm, Sweden as well as production and R&D labs near Denver, Colorado.
Links:
Nilar nilar.com
CalCars Initiative calcars.org
TechMash 2007 cmp.com
A live discussion and a preview of the Prius teardown (for members)
facebook.com
TechMash live conversion of a Toyota Prius hybrid into a PHEV
eaa-phev.org |
