Batteries Evolving

Modern cars are becoming energy hogs. With all the gadgets, computer controls and entertainments systems -not counting all the other do-dads, noise makers and other pieces of electronic claptrap people attach or hook up onto them -the lowly car battery is often abused with trying to keep the car operating, showing where the driver is on the GPS and entertaining the kids with the umpteenth viewing of some Barney DVD on the player in the back. OK, I exaggerate a bit -but only by a bit. The Barney DVD only gets played about five times before Dad goes utter bonkers, pulls to the side of the road and throws the offending shiny disc like a Frisbee into oncoming traffic; if not himself in the process.

Still, joking aside, today’s car battery is very much put upon. There are more electronics and computer systems today running a conventional automobile than ever before, and it’s only going to get more complex.

Greg Shull, marketing development manager with Interstate Batteries, only has to point to the proliferation of computer processors on vehicles today to illustrate the strains being put on batteries.

“According to our Technical Services Group, there is a car today that has some 80 processors,” Shull says. “We have vehicles now that have computer- controlled security systems to entertainment systems, vehicles that are pulling together Bluetooth, cellular phone technology and computers. All of these systems and devices pull more (power) from the car battery, even when it is not running.”

Often termed ‘parasitic loads,’ this constant tapping into the car battery to keep things running means the battery is always being drained, leaving them partially charged. In the short term, this is not much of a problem for traditional batteries, but over time, this continual draining begins to physically affect the battery. Known as sulfation, this is when a lead-acid battery loses its ability to retain a charge after being in a state of partial charge over a long time. How does this happen? Well, it is due to the chemistry involved in lead acid batteries and how they work. Lead acid batteries make electricity through a double sulfate chemical reaction, where the lead and lead dioxide material of the battery’s plates react with the lead sulfate which the plates are immersed within.

In a new car battery, this lead sulfate remains in a form that is amorphous and is very easily converted back to lead, lead oxide and sulfuric acid when the battery is recharged regularly. But if the battery is always being tapped for power and remains over long periods of time in a partially-charged state, then the lead sulfate crystallizes onto the battery plates, making the plates less conductive to electricity. This also makes it much more difficult to return the battery to a full charge and for the battery to produce a steady, consistent electrical charge.

Mil Ovan, senior vice-president, cofounder of Firefly Energy Inc. says this sulfation effect is sometimes known as a memory-effect, and battery makers are developing new kinds of battery designs to overcome the problems caused by sulfation.

That solution is abandoning the traditional design of car batteries with their positive and negative plates. Firefly instead developed the Microcell composite foam grids that are suffused in lead oxide slurry. This technology forms the basis for the company’s Oasis battery, which is currently being tested in American trucking fleets, and allows for more surface area to be created than conventional plates, improving the battery’s recharge capabilities and helping eliminate the memory effect of the sulfating-effect that is seen in conventional batteries, according to Ovan.

“Our battery design has the ability to handle a deep discharge and pop right back up to its original charge over many discharges and over many more cycle times than traditional designs,” Ovan adds.

Ovan says the design gives the batteries a longer lifespan, more efficient power and is better suited for more extreme environments of cold and heat.

Exide Technologies has also opted to develop a new kind of battery design in order to provide car owners with more reliable power and longer life. If one were to open up the company’s Orbital battery the first thing one would notice is the abandonment of the traditional battery plates. Instead, one would find six tightly-wound orbitec grids and acid-permeated viterous separators — tightly wound cylin ders instead of plates. What this means for a car owner is the design will not allow any contamination to enter the cells thereby compromising the battery’s life and energy performance, and the isolated cells will then have a greater reliability.

“This battery is going to be for applications where there is more involved than starting the engine,” says Paul Cheesman, vice-president of research and development and engineering with Exide. The Orbital is ideal for vehicles that come with a lot of electronic gadgets and other systems that are known to drain power, even when the vehicle is idle or parked.

Not every battery manufacturer has moved away from the traditional battery design. Interstate Batteries continues to improve the traditional automotive battery design with such enhancements as a PowerFrame positive grid. The PowerFrame is made to insure all of the plates are within high tolerances and to improve consistency. The negative plate has been enhanced to reduce the effect of internal heat and the electrolyte mixture has also been changed in order to better handle discharges, and to more effectively accept recharges after a particularly severe discharge.

“Because of those improvements our battery technology is improving, offering longer life and performance,” says Shull.

SSGM

REFERENCE LIST

Exide Technologies www.exide.com

Firefly Energy Inc. www.fireflyenergy.com

Interstate Batteries www.interstatebatteries.com