Computer render of battery pack design

Engineering challenges are like a siren's call to Neal Saiki. Since leaving Zero Motorcycles in early 2011, the company he co-founded with his wife Lisa, he's spent lots of time and effort wrestling with the human-powered helicopter conumdrum. As engaging as that might be, however, he still hasn't been able to keep himself from considering how to build a better electric motorcycle; work that has, it seems, proved slightly less Sisyphean as he has just announced a pretty cool battery pack breakthrough.

His approach tackles the big battery drawbacks of cost and energy capacity head on by employing the same "18650" cylindrical cells that Tesla Motors so successfully uses. Then, to get around the labor intensive connection method of welding thin strips of nickel to each one, he has devised a way to mechanically connect the cells with enough pressure to keep the current dependably flowing through them.

This configuration makes it easy to replace a single cell if it goes bad – each one is thermally monitored for signs of failure – and also makes it super easy to upgrade when new, better cells become available. What's not to like?

Saiki calculates a 200-pound pack will hold a nominal 16.1 kWh of energy using 1440 individual cells. That, he says, should provide for a real-world, driving-down-the-highway, 100-mile range. By contrast, the "100-mile" bikes by Zero Motorcycles and Brammo hold around nine kWhs.

The system can also be adapted to four-wheeled vehicles. In that application, the pack would be arranged as a three-inch thick plate holding 26.6 kWh of energy per square meter (22.2 kWh per square yard). It's too soon to say whether or when the pack will be commercially available. Saiki's new company, NTS Works, is currently looking to work with "select OEM's on custom battery pack design and licensing." Scroll down below for the official press release for more details.
Show full PR text
NTS WORKS EV BATTERY BREAKTHROUGH

SANTA CRUZ, CA., (May 17, 2012) - NTS Works Inc has revealed details of a revolutionary electric vehicle (EV) battery technology. The "NTS" in the company name is the initials of Neal Tate Saiki, founder of the leading electric motorcycle company, Zero Motorcycles Inc. After retiring from Zero last year, Neal has formed the new company in Santa Cruz, California which focuses strictly on technology development. The new battery technology will allow many EVs to double their range at the same battery cost that they have now. More importantly, the new batteries are easy to disassemble and repair. This is an important feature for consumers that want to get the full lifespan out of their expensive electric vehicles.

Electric vehicles have had sluggish sales primarily due to their limited range and high cost. This new technology addresses both of these shortcomings. The battery technology is a method of connecting extremely high energy lithium ion battery cells into larger sized battery packs suitable for EVs. Although these battery cells have been on the market for a couple of years, it is very difficult to inexpensively connect them together without causing them to overheat. A leading electric car company also uses these cells in their cars, but there have been concerns regarding the high cost of replacing the battery pack. Replacing a few bad cells out of thousands is not easy to do when they are connected together by welding. Welding is the traditional way these small cells have been connected together.

The NTS Works battery pack is composed of small cylindrical lithium ion cells called 18650 cells. They were originally developed for laptop computers and the standardized size and shape has become the most popular in the lithium battery industry. The popularity of tablet computers has caused sales of laptop computers to stagnate. This has produced an oversupply of the lithium ion 18650 cells. The price for the cells has been steadily decreasing over the years while the energy capacity has been increasing. According to Neal Saiki, "Everyone in the EV industry has wanted to use lithium ion 18650 cells because they are light-weight and inexpensive, but figuring out how to build packs from thousands of these cells has stymied all the smaller companies in the EV industry. Only the biggest car companies have been able to do this up until now."

The breakthrough in connecting the cells together was solved with an entirely different way of mechanically connecting cells together with pressure. "It's similar to the way a flashlight battery is held in place by a spring, however, if you used a spring in an EV battery it would quickly melt due to the enormous energy in an EV battery. It has been incredibly difficult to come up with an inexpensive solution." says Neal Saiki.

There is one important technical limitation to the NTS Works battery technology. It isn't as well suited to extremely high powered bursts of energy. For this reason, it probably will not be applied in hand power tools or high performance vehicles. These vehicles can use all of their battery energy in less than an hour. NTS Works does not have any plans to use the technology in electric car or motorcycle racing. This new technology, however, is well suited for transportation EVs where consumers generally want to be able to ride scooters and motorcycles for at least an hour. For electric cars, consumers generally want to be able drive two or more hours between charges. In these applications, the batteries can be smaller, lighter and less expensive.

The first application example from NTS Works is for an electric motorcycle with a 15 kilowatt hour (kwh) battery pack. This battery has 67% more range than the best electric motorcycle on the market today. It is also shaped in a thin package that allows a motorcycle to have a very low aerodynamic drag at freeway speeds. This will give freeway commuters the ability to ride for an hour on the freeway at 70 mph. For other applications such as cars and ATVs, it is very desirable to have the battery in a thin sheet. The thin sheet of batteries can easily be built into the floor of the vehicle thus leaving generous room for passengers and cargo.

ABOUT NTS WORKS: NTS Works Inc is a product development company that is in the process of licensing the battery technology to several manufacturers in the EV industry. Consumers will see vehicles that use this technology as soon as next year. The NTS Works battery technology is patent pending.

For more information on NTS Works Inc or to learn more about the battery breakthrough technology visit: http://www.ntsworks.com.