A123 LiIon Battery Pseudo Extra


Every so often I have to slap myself in the head. I’m surprised that we haven’t covered these things by now. DeWalt’s been selling a LiIon 36 volt battery pack that’s full of the latest A123 cells. These are the same ones that were used in the Killacycle. (I think they’ve got a new batch of cells now).

A while back, [Jeff] sent in a circuit for using multiple packs, leaving the internal BMS in place. [The link is fixed now]

[Robert] sent in a scooter that’s been designed to run these same cells. The custom fabrication and machine work looks fantastic.

CCCamp 2007: Quad-copters


R/C quad-copters have been quite popular at CCCamp. Our friend, Dan Kaminsky shot this video of two different models in flight. The first is a 10K Euro commercial version, but the second one is a 500 Euro home built one. The commercial unit has a head mounted display so you can fly it from the onboard camera. There is a second video after the break that shows the maneuverability.

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Wiimote Car Accelerometer


This one’s pretty simple, but anyone who’s ever spent time tweaking an engine will appreciate it. [Kevin]’s been using a wiimote to measure the acceleration of his car. He put together a script to dump the accelerometer output to a CSV file, then graphed it with Excel. He notes that the accelerometer output isn’t that precise, but it’s good enough to give you feedback on your mods.

AVR Modified EV Charger


[Gary]’s built some nice AVR projects. The most interesting is the charge controller/monitor he built for his EV Porsche. Each board controls a charger – with one charger per battery. When the system isn’t charging the batteries, it provides real-time data to a VFD display in the dashboard of the 1978 Porsche 924. Hopefully he’ll notice the spike in traffic and will update the charger project page.

Human Electric Trike Project


While I’m waiting for my last stepper motor, I’ve been pondering my electric motorcycle build. While eyeballing batteries, I ran across a really impressive human/electric recumbent bike project. [Bob Dold] built this for his M.S.M.E. Thesis project. The frame was built from bonded aluminum. The flat parts were cut via waterjet service, and the rest were machined by the college’s machine shop. The 1000w motor (and controller) came from a Schwinn X1000 electric scooter. Looks like a four link suspension (plus steering and shock linkages). Interestingly, he’s using some USB data loggers for voltage and current(with a shunt) and combining it with GPS data to track real world performance.