IMPORTANT: the part is designed for laser welding, you need suitable equipment to attach bus bars to their terminals. We are experimenting with TIG welding and will post results shortly. Make sure to use as little heat as possible, to avoid damaging the cell’s internals. Use safety glasses, as improper handling can cause them to fail destructively (they are filled with a liquid electrolyte).
A 650 Farad / 2.7V ultracapacitor with an extremely low internal resistance of max 0.8 milliOhms from market leader Maxwell. This is a discontinued product, but as they have been in storage since 2007 and have not seen any current not high temperatures, we found that they are in very good condition. Measured ESR is below spec (0.5 milliOhms typ), capacitance at 100%, leakage current also in spec. The datasheet is available here.
Their regular price was in the order of 50€. We are giving them away to DIYers as we could make a very price competive acquisition of ~ 800 parts, and can support cool projects this way – please let us know what you made of them.
With a short circuit current of 3400A, these are well suited to power a kWeld. Based on the measured cell characteristics, a 4S pack should deliver roughly 1600A welding current.
If you need larger quantities of these, then please regard their original packaging of 30 pieces if possible.
|Dimensions||10 × 10 × 10 cm|