New battery, and controller

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astrowolf67

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Right before Christmas, my 10 year old jump start battery finally died on me. While walking through Wal Mart one day, I came across a Lithium Ion jump starter, on clearance for thirty bucks. This got the wheels turning, and, I figured, it's Wal Mart, if it doesn't work, well, you know. As it turns out, this little battery has been used quite a bit in the month and a half I've had it. It's jump started three vehicles, powered my telescope mount through a few nights of observing, and now, has a place in a new relay controller I recently built. The battery (shown in third pic) is rated at 12,000 mah, and uses a RC battery EC5 plug, which is commonly available at RC shops. My goal of building my new controller was to keep it simple, light weight, easily found parts, and self contained.

The controller uses a 9v battery to provide power for continuity check, and relay activation. It is connected to the pad box using a 25ft standard four conductor phone line (I've also tested it with 50ft as well). The ignitor leads connect to the pad box via standard 110v outlet, and, are made of a cheap 15ft extension cord. In the future I plan to add a safety at the pad box, that will disconnect the 12v battery, and, would like to add a buzzer to warn of a shorted relay. I'm a habitual clip shorter anyway, so for my use, I'm in no rush. For now, I'm very pleased with the operation, and, have tested it with both low, and high current ignitors.

Launch-Controller1.jpg

Launch-Controller2.jpg

Launch-Controller3.jpg
 
Thank you for posting this. Lots of people seem to use the lead-acid jump starter boxes, but these lithium ion units are a lot smaller. I couldn't find any other evidence on the whole of the internet that it would work, so I appreciate you sharing your experience. I would add that they (amazon) sell EC5-to-female-cigarette-lighter adapters so these little devices could be swapped into an existing system based on a lead-acid jump starter.

Anyhow I know it's an older post but I was glad you made it. I wonder if you could post any updates? Do you find the capacity pretty good, does it stay charged in storage pretty well, did you ever add that buzzer?

Thanks
Eric
 
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