WIMA starter capFor optimum cranking of a diesel / combustion engine currents of more then 1000A are needed.

A middle sized car for example needs a starter performance of approx. 1000A initial pulse to reach the maximum breakaway torque followed by a continuous current of approx. 100A. The start cycle itself needs up to 2sec. To supply this amount of power, a conventional battery needs a capacity of more than 70Ah. By using a SuperCap Module e.g. 200F/14V, consisting of 6 SuperCap C 1200F in series, which will be connected in parallel to a small battery (e.g. 12V/12Ah) it is possible to crank the combustion engine more reliably and with higher rmp even at temperatures down to less then -30°C. In comparison to a conventional battery which weighs about 18kg the combination of the smaller SuperCap battery weighs less than 5kg and requires even less ground space. The SuperCap Module is immediately recharged at start up by the board net and therefore makes it ideally suited for start and stop applications.

Large diesel engine starting applications differ greatly from starting small engines due to the heavier weight of the moving parts. A locomotive diesel engine (16 cylinders, 65l), may need an initial surge of approx. 2500A to power up the hydraulic pumps, which in turn creates the pressure to suspend the engine shaft before starting. Once the engine changes from being in static friction to sliding friction the current requirements drops back into the 800A range for the rest of the start cycle. During cold weather, there is a so-called “pre-heat period” of 30 – 60sec. This pre-starting preparation will consume most of the capacity of conventional battery packs. The high initial start current has a big effect on battery life, even though they are designed to meet it. By putting a SuperCap module in parallel with the battery, it is possible to get up to 75% more starting torque at a higher cranking rmp. That’s what is needed to get also a cold diesel going reliably.

SuperCaps are maintenance-free and do not degrade with time like lead-acid batteries. Life-time expectation of >10 years and up to 1,000,000 discharge/charge cycles can be reached. Using SuperCap modules the reliability of system operation will significantly increase. Unlike conventional batteries, the SuperCaps don’t contain toxic materials and can be considered as safe components. Connected in parallel to batteries the SuperCap module will cover and take all current peaks like e.g. starter current and by this behaviour improve life time of the battery. All these characteristics result in remarkably lower cost and higher system reliability.

For additional information on WIMA SuperCap modules contact TAW Electronics at:

TAW Electronics Inc
4215 W. Burbank Blvd
Burbank, CA 91505
Ph: 800 339-2288