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MichaelMeissner
03-03-2013, 09:57 PM
I'm starting to think about moving the Teensy to do effects for my steampunk cameras. Some of the events that I do are outdoor events, and that means rain is always a possibility. My main camera is weather sealed, so that is not an issue, but the Teensy needs to be enclosed in a weather sealed enclosure. I would like the enclosure to be as small as possible, that effects the choice of batteries. I also worry that weather tight enclosures might cause the Teensy to overheat if the voltage regulators reduce voltage by converting it to heat. I could go with an enclosure with holes on the bottom to vent heat, but ideally, I would go with a sealed case, with wires run through weather sealed cable glands.

So I'm looking for thoughts on batteries to use. If possible, I want to use rechargeable batteries. I would prefer to not change batteries during the day, which means I need the unit to run 12+ hours before needing to recharge the batteries, but depending on the cost, I might consider several light weight/cheap batteries that I could change during breaks in the action, over a single expensive option.

I currently use batteries that are meant to recharge cell phones, and provide 1-2 USB 5v ports to power devices. I have an EVOpower 5 volt, 1amp battery with 5 amp/hours of capacity, that could run an Arduino for 4 days doing standard blink. I also have an Energizer 5 volt, 0.5 amp battery with something like 1 amp/hour of capacity. These batteries work ok, but are a little big, which means bigger enclosures.

I could imagine getting a Lipo battery, and voltage regulator to provide 3.3v volts. I would prefer something that has voltage regulation, so that it shuts down rather than deplete the battery to dangerous levels. I am unsure of how to size the battery so that there would be enough capacity to run for a whole day. As I mentioned earlier, I do worry somewhat about heat buildup also if the voltage regulator vents excess energy as heat. In terms of form factor, there are Arduino shields to make this simplier, but for the Teensy, I imagine I will need to build it on a protoboard.

Since I shoot Olympus cameras, I have a bunch of Olympus BLM-5 batteries (7.2 volt at 2000 maH) and BLS-5 (7.2 volt at 1150 maH) batteries. I could imagine using these instead of getting separate lipo batteries if I could make sure I didn't deplete the batteries to dangerous levels, nor damage the Teensy. It would certainly be convenient not to have yet another battery charger lying around.

I also have a bunch of Nokia 5C batteries that are essentially single cell lipo batteries.

I don't think rechargeable 9v batteries have enough capacity for a full day.

If I used 5 or 6 rechargeable AA batteries, it should work, but a bunch of AA batteries has the same size issue as the cell phone charger batteries. I could use 2 AA batteries boosted up to 3.3v with something like the Adafruit minty-boost setup. Since I have plenty of AA batteries, I could just change them every couple of hours. However, as I said previously, I really would prefer not to change batteries at all during the day.

AAA batteries would give me a smaller size and a corresponding smaller run time. I don't have as many rechargeable AAA batteries as I do AA, so in terms of cost, it might be simpler to go with lipo batteries.

I am sure there are other battery types I haven't covered.

I know in terms of power, what I want to do, mostly it is sitting around until there is a keypress event and then it will do some action(s) for a period of time, and then go back to wait for the next keypress. The keypress might be an actual keypress, but it could also be an an infrared controller keypress, or maybe bluetooth. I imagine eventually, I will want to run a hobby motor for a short period of time or a servo. I assume, the bluetooth will probably consume a lot of power, as will the motors, if they are running for a period of time.

So for the people making battery operated gizmos with the Teensy 3.0, what type of solutions did you use? :confused:
:cool:

ZTiK.nl
03-04-2013, 09:41 AM
I had a similar question when I got started, and you were the person who gave me advice on my battery...
Unfortunately I have been banned from the forum, and that particular post doesn't exist anymore, so I thought I'd mention it again ;)

I am using a MiPow PowerTube 2600mAh (http://www.conrad.nl/ce/nl/product/200240/Mipow-Powertube-2600-zwart-SP2600M-BK-Mipow-2600M-Reserve-accu;jsessionid=76D754A224655528B3D289CB60BD9E7C.A STPCEN18) battery with both USB and MicroUSB connections.
It can be charged with (max) 1000mA, which means it should be fully loaded in 2.5 to 5 hrs, depending on your USB powersupply used to charge.

The size of the entire battery is around 3x the width of the Teensy 3.0 and about 1cm longer than my 2.8" TFT (1cm = 0.39 inch)
300

MichaelMeissner
03-04-2013, 11:40 AM
I had a similar question when I got started, and you were the person who gave me advice on my battery...
Unfortunately I have been banned from the forum, and that particular post doesn't exist anymore, so I thought I'd mention it again ;)


It must have been that other forum.

As I have answered in other posts, I generally like the USB charger batteries. But I thought I would ask about other options. The first enclosure I picked (Adafruit small plastic enclosure) was too small for either of my USB battery chargers, particularly with the 5cm (2in) or so the cord adds when you plug it in. I have other enclosures book marked that probably will work (Pelican 1015 and 1020) with the existing batteries. The problem with the Adafruit enclosure is the 4 screw posts inside eat a lot into your usable area. Here is the Adafruit enclosure that I bought: http://www.adafruit.com/products/903



I am using a MiPow PowerTube 2600mAh battery with both USB and MicroUSB connections.
It can be charged with (max) 1000mA, which means it should be fully loaded in 2.5 to 5 hrs, depending on your USB powersupply used to charge.

The size of the entire battery is around 3x the width of the Teensy 3.0 and about 1cm longer than my 2.8" TFT (1cm = 0.39 inch)

I have a similar battery book marked in ebay. It looks like I just have to bite the bullet and get a longer case. Thanks.