Finding Multiple Uses for Electric Car Batteries

Electric car made from batteries
Electric car made from batteries

Many of the advocates of the electric car revolution have discussed about repackaging the battery packs for cars to become energy storage devices once their useful run as car batteries run out. This idea was best shown when ABB and General Motors have been undertaking a project of a similar nature with five (5) Chevy Volts.

The Volt battery back is able to hold sixteen kilowatt hours when brand new and the prototypes from the partnership would be able to carry ten kilowatt hours per pack. The program would have five battery packs placed together in an array that would be able to provide two hours of electricity for three to five houses of average size. The demonstration showcased a lighting and audiovisual equipment in a structure in San Francisco.

The batteries were not even challenged as each pack was able to provide up to 111 kilowatts of power but the five batteries were only able to provide 2.5 kilowatts. This is significant as low power demand for these kinds of batteries would extend their service life.

The concept behind the prototype is to provide for a market for used batteries as well as allowing for resale value that would lower cost of ownership. It would also provide for a distributed storage system that would provide backups for areas with low energy supply or have a storage system for intermittent energy sources such as solar panels and wind machines until its delivery for use in the power grid.

The concept can also be quite useful in an area with a high population of electric cars as the electricity required to charge vehicles arrives at a steady stream and be stored in the battery array available to be tapped when needed. In this set up, the battery pack would work like a tank on a toilet, readily available for a quick supply.

The package set up also provides an inverter that would convert direct current from a battery to an alternating current, usable as electricity from an electric socket.  The requirement to be allowed into the program, according to Pablo Valencia, Senior Manager for Battery Life Cycle Management at GM would be the battery pack is no longer suitable for a car, where only thirty percent or less of its life has been used.

He added, “This leaves a tremendous amount of life that can be applied to other applications.”

Battery Breakthroughs and Issues

firesign
firesign

In a breakthrough discovery, German scientists have developed a new fluid that can assist in cooling the large and expensive batteries of electric cars. The benefit the discovery provides is the extension of their service life and one more step in the improvement of the cost efficiency of electric vehicle transport.

The fluid has been named as CryoSolplus and has the capability of greater heat absorption compared to air or water. This would allow for tighter packing of batteries according to the research team of Fraunhofer Institute for Environmental, Safety, and Energy Technology located at Oberhausen, Germany. 

The battery pack would generate nearly 45 degrees Celsius of heat on a regular day. Its best working ambient temperature is between 20 and 35 degrees and under those conditions, the battery would only be able survive half of its actual service life. With the cost of the battery pack nearly half the total price of the vehicle, finding ways to extend its service life has become imperative for many research and development teams.

Current technologies only use air to cool battery arrays or there are no cooling systems at all. Air is not a very efficient heat absorber and requires space in order to travel in between heat generating battery arrays. Water on the other hand, is a heat conductor but requires a storage tank to be effective.

CryoSolplus consists of water, paraffin, anti-freeze and a stabilization agent, according to the research team. It has three times as much ability to absorb heat compared to water, thus requiring a smaller storage tank, creating more space and weight savings for the electric car manufacturer. The research team says that the solution and the cooling system would cost just a little over 100 euros in the manufacturing process. When heat is absorbed, the solid paraffin droplets melt and store the heat. When the solution cools, the paraffin droplets solidify.

This technology may be too late for Fisker Automobiles Karma, as it issued its second recall when two mysterious fires again hit the government subsidized electric vehicle. According to Fisker spokesperson Roger Ormisher, “Fisker engineers and an independent fire expert had identified the root cause of a fire that engulfed a Karma parked outside a Woodside, California grocery store last August 10.” He added, “The investigation located the ignition source to the left front of the Karma, forward of the wheel, where the low-temperature cooling fan is located. The final conclusion was that this sealed component had an internal fault that caused to fail, overheat and start a slow burning fire.”

Fisker has since announced a voluntary recall “with respect to this cooling fan unit” and stated it has already coordinated with its retailer. Unfortunately, the cooling system development may have come too late for Fisker.