Traction battery

Traction batteries are used to provide motive power for electric or hybrid vehicles. A traction battery can be found in a forklift, an electric "Golf Cart", a riding floor scrubber, an electric motorcycle, as well as the new hybrid vehicles being released today.

Traction batteries differ from starting, lighting, and ignition (SLI) batteries because they are designed to give power over sustained periods of time. Deep cycle batteries should be used instead of SLI batteries for this application. All batteries are comprised of cells, wired in series and parallel circuits to achieve the appropriate voltage and capacity. Traction batteries must be designed with a High Ampere Hour capacity, usually a larger voltage (12v and up). The mark of a superior battery then is optimized weight to volume (power density), and weight to power ratios (lb/AH). The vehicle will be required to carry the battery, so the lighter, smaller, and more powerful the better.

Traction batteries are routinely abused in real life, as work schedules require, they are used all day, and fast charged all night. These fast charging rates with large chargers keep the implements on a 24 hour schedule, but put the batteries to the test. Forklifts for instance are usually discharged and recharged every 24 hours of the work week on a dock.

Types of Traction Batteries available today:

*Lead-acid_batteryFlooded batteries are the cheapest and most common traction batteries available, usually discharged to roughly 80%. Flooded lead acid batteries, will accept high charge rates for fast charges. However, when fast charging, these can be messy. Flooded batteries do require maintenance, and are not for use in public areas per some federal and state laws.

*Absorbed Glass Mat valve regulated Deep Cycle Lead Acid BatteriesAGM Batteries are more expensive as it takes more to build them, but with reduced internal resistance and more pure lead contents, they charge more quickly and house more power in a smaller package than their flooded brothers. However, they are only to be discharged to 50% to maximize life cycles¹. AGM offers power, without the mess, outstanding charge times, and are OSHA Approved for public spaces. AGM Batteries will not crack or freeze, they do go dormant at -40 F.¹

Both varities of Lead Acid battery (flooded and AGM) are over 98% recyclable, and are therefore some of the best for the environment. ²

*Nickel_metal_hydride_batteryNiMH batteries have an alkaline electrolyte, usually potassium hydroxide and are a dry cell alternative to the flooded lead acid varieties above. However, they are very expensive.

*Lithium_ion_battery could replace them all, and my hybrids are starting to use them. However, this battery is cost prohibitive at this time for many applications.

*Nickel Cadmium batteries require proper disposal due to their content of cadmium.

*Fuel cells running on hydrogen or other fuels are in development.

References

* [http://www.bdbatteries.com/marinegraphs.php AGM Deep Cycle Battery Graphs]
* [http://www.batterycouncil.org/LeadAcidBatteries/EnvironmentalRegulations/tabid/72/Default.aspx Lead Acid Batteries and the Environment]