mobile power recommendations....help

Im working on an arduino project that just simple has to be self contained and mobile. I can share the details in anyone cares. the issue at this point is how to power it mobily (battery)

I consider myself a novice, but have a pretty good grasp on battery power. I have changed out the UNO for a mini to help the power draw.

The issue consists of this:

#1 the main sensor of my project draws “<750mw”
#2 I have a 5v voltage regulator feeding it all.

So I need a battery solution that can feed min of 7v to power the voltage regulator.

my first idea was to power it all off a disposible 9v. Knowing the mah rating sucked I tried anyway and it only lasted about 20 mins or so. LOL.

can anyone help recommend a decent mobile power solution?

TIA

Hi, 2 Lithium (LiPoly) cells 3.7 * 2 = 7.4 volts.

MANY sizes and mA-Hr ratings available.

Space? Weight? How easy to recharge? (Multicell LiPoly Batteries need a balancing charger. If you can pull two cells out and put them in a charger this takes care of that.

Where are you located?

AA alkalines or NiMh rechargeables (2,000mAh) would run for around 13 hours. 5-6 cells though.

Maybe your sensor does not have to be on all the time- can you turn it on every second or two to save power?

For efficient power regulation, go on ebay and search for UBEC regulators that the RC crowd uses.

terryking228: I am located near Philadelphia PA USA. Could you point me towards a website with some of the batteries you speak of? I have a couple li-pos and have read not to stack them on my own because if it being danergous. I can you point me towards a 7.2 stacked li-po?

prairiemystic: I could do this as a "last resort" I would perfer to not have a 6AA pack in the project, but I will if need be.

thanks for the REAL help guys. I appreciate it!

How mobile is your project? Does it stay still at all? Maybe you could get away with a small solar panel on top that would charge a battery or help lessen the load atleast, assuming your load is about 200ma, this would almost power it entirely or atleast charge a battery http://www.altestore.com/store/Solar-Panels/Kyocera-14W-12V-Mini-Solar-Panel/p718/

Look for a supplier of 18650 LiPo batteries (cells) in USA.. (Shipping is a problem by air)..

I am looking at a nice battery case with 5V 2A switching supply built in that uses 2 series 18650 cells (or 4 in series/parallel).

Here's a photo, but labels in Chinese.. My partner in China is shipping me one... Should be way cool for robots... Has automatic shutdown if over discharged etc etc. Probably sell for $15-18 without batteries (About $1.50 each in China, but USA??)