9V battery clip

Something like this 9V battery clip would be very handy for the Arduino. It comes with a plug that fits right into the Arduino’s external power socket.

http://www.adafruit.com/index.php?main_ … ucts_id=80

Why $3 for it. Salvage one from a used-up battery, just you need to solder two wires . It works quite well

Daviddd:
Something like this 9V battery clip would be very handy for the Arduino. It comes with a plug that fits right into the Arduino’s external power socket.

http://www.adafruit.com/index.php?main_ … ucts_id=80

Note that AdaFruit’s connector is molded, which should make it a lot more rugged. I went through a couple of packs of the cheap 9v connectors. Either the cover over the connector would tear or the thin gauge wire would break off after connecting it to the prototyping board a few times. It seems like a lot of these connectors assume that one would only a plug it in once or twice in a lifetime.

The approach that I ended up using was two fold:

  1. I purchased a number of battery connectors that take 2, 3, 4, and 6 AA (or AAA) cells and have the same connector as a 9v battery. I then found a high quality molded connector with decent wires that connect to a 2.5mm plug. This provided a flexible way of getting my desired voltage at a higher current rating than I could get with a 9v battery.

  2. I later purchased a number of battery connectors with an integrated on/off switch and attached a 2.5mm plug to the wires coming out of the battery pack. I like this approach slightly better because I can’t plug a 9v battery into the prototyping board when the board can only take a maximum of 6v. Although I didn’t do this, a colleague of mine did because they assumed that since the plug had the same connector as a 9v battery, they could plug a 9v battery into it. Sparkfun sells these types of battery connectors, but without an on/off switch. As I wanted the switch, I ended up getting mine at Jameco. If your board has an on/off switch of it’s own, the ones at Sparkfun will work well.