Plastic Batteries Are Here... 
at least in new ultra thin laptops. 

by Remy Chevalier  
(Written sometimes back in 2000...)

Ask any EV enthusiast and they'll tell you, the single most important thing that is holding back EVs is the weight of its batteries. Jay Baldwin, one of the founding fathers of Whole Earth Review and currently on the board of the Rocky Mountain Institute's HyperCar project, calls EVs battery chariots

Plastic batteries have long been a dream of EV builders, for obvious reasons. Plastic would be a lot lighter than current batteries containing metals like lead or even hydrides. Then two years ago the Air Force funded research at John Hopkins University through the military technology transfer program. It led to the first proof of concept plastic batteries in the civilian sector. But last year MIT's Technology Review Journal reported that these prototypes were having a hard time finding financial backing for commercialization. It seemed battery companies were stretched too thin already with previous generation product that hadn't recouped initial investment costs.  

That didn't stop Ultralife in New Jersey from going ahead quietly. They have just announced a new line of ultra thin laptop plastic batteries for commercial applications. When their marketing department was asked if this was the John Hopkins technology, they replied: "They are the same, but different..." Read into that what you want. If Panasonic hadn't run away with Nickel Metal Hydride, we'd still be waiting for GM Ovonics to make them available for EVs.  

It took about five years for NiMH to scale up from laptops to EV systems. I expect it will take about that long to see plastic battery packs designed for EVs, unless the EV drag racing craze explodes and builders are willing to spend anything to win or the military makes it a number one priority. Last week Bill Moore, editor of EV World, posted Ultra life's stock market chart on his website at which showed a dramatic dip in price. I expect those outside the EV industry don't realize the potential of plastic batteries yet, so it may be the best time to buy. In a few years, whether Ultralife will be the breakthrough company or not, car parts will double as electrical storage molded into components.

For all the specs and product information, go directly to the Ultralife website:

Ultralife Batteries, Inc.
2000 Technology Parkway, Newark, NY 14513 USA
(315) 332-7100; Fax (315) 331-7800

Executive Sales Offices
Ultralife Batteries, Inc.
160 Summit Avenue, Montvale, NJ USA 07645
(201) 930-4900; Fax (201) 930-1144

United Kingdom Offices
Ultralife Batteries (UK) Ltd.
18 Nuffield Way, Abingdon OX14 1TG England
+44 (1235) 542600; Fax +44 (1235) 535766

Ultralife's advanced Solid Polymer Rechargeable Battery -- the first battery of its kind in the world to be shipped commercially -- offers an unprecedented combination of long life, safety and design flexibility. Batteries can be configured in virtually any prismatic shape, and as thin as 0.040 inch (1 mm), to fill virtually any space efficiently. Cells can be configured in series or parallel to achieve optimum voltage, capacity, and rate capability for a given application. This leading-edge rechargeable battery technology is ideal for cellular telephones, notebook computers, and other portable electronic applications.

Solid Polymer Rechargeable Batteries

Cell Voltage:
Ranges between 4.2 and 3.0 volts per cell. Typical operating voltage is 3.7 volts per cell.

Energy Density:
Up to 125 Watt-hours per kilogram; up to 250 Watt-hours per liter.

Charge at a constant current (C rate maximum; C/2 recommended for best performance) to 4.2V. Continue charging at a constant voltage of 4.2V until current declines to C/10. Batteries should be electronically controlled in both charge and discharge modes.

Discharge Rate:
Maximum recommended continuous discharge rate is 2C, with pulses up to 5C.

Discharge Profile:
As is typical of lithium-based systems, the discharge profile of the SSS (TM) battery is flat at low current drains and sloping at higher current drains.

Charging Temperature:
0 C to +45 C.

Operating Temperature:
-20 C to +60 C.

Storage Temperature:
-40 C to +60 C.

Cycle Life:
More than 500 charge/discharge cycles at 100% depth of discharge at both the C rate and the C/5 rate to 80% of rated capacity.

Self Discharge:
Less than 10% per month.

There is no memory effect that might prematurely shorten cycle life, as with NiCd batteries.

Form Factor:
Consisting of flat, flexible plates, Solid Polymer batteries are ideal for prismatic configurations. Minimal packaging and a high percentage of active materials enhance energy density.

Because the electrolyte is solid, Solid Polymer batteries cannot leak or experience gassing. They are also safe if opened, as no metallic lithium is present. In addition, Solid Polymer batteries are extremely resistant to abuse from over-charging and discharging.

Environmental Factors:
Solid Polymer batteries are environmentally friendly. There are no toxic metals present, such as cadmium, cobalt, lead, mercury, or nickel, and there are no restrictions on disposal.

With no metallic lithium present, Solid Polymer batteries have no transportation restrictions.