Battery powered device hardware design tips

I’m working on a prototype product(Wifi motion sensor) that will be powered from a battery source, it has a mega328(arduino bootloader, with sleep mode on and wake on interrupt,and WDT in case it hangs up), a PIR motion sensor , and a CC3000 break out board.

Power saving is done in software, but what type of battery should I use? I initially used 2AA with LT1302-5 boost converter, but I think it was not able supply enough current for the CC3000 module, it could not start the SSID scan also the LED on the break out board dimmed out a bit.

Now I’m thinking of using 4AA and using a 5v LDO regulator.

How do I go about it?, what other options I have, I need 5V to operate the circuit. I’ve never designed a battery powered project before. Should I use different type of battery,LiPo perhaps?

Peak current of 150mA is drawn when communication is going on, draws and 10mA when its asleep. Let me know if you need more details.
Circuit Diagram

LT1302 IC is soldered exactly as in its data-sheet.
Source code
https://github.com/hemalchevli/Sketchbook/blob/master/PIR_LP/PIR_LP.ino

This is how to looks

Any chance that you could add your current circuit diagram, there might be some minor problem with your circuit that is causing it to draw more current than you expect. – Mark Booth Sep 20 ’13 at 17:59

CC3000 can draw up to 300mA at times, perhaps at startup. I would design with a larger booster. – Gustavo Litovsky Sep 20 ’13 at 19:04

@ Mark Added the circuit diagram, @GustavoLitovsky I didn’t see that spike, perhaps my multimeter is not fast enough, can you suggest the lager booster IC? – Hemal Chevli Sep 21 ’13 at 5:45

@HemalChevli: You will only see it on an oscilloscope as a dip in voltage if you don’t have enough current to the device. – Gustavo Litovsky Sep 21 ’13 at 14:56

Battery powered device hardware design tips Schematic

Just a general comment, that a AA is good for ~ 2500 mA/Hr, so 2 of them will be good for 5000 mA/Hr. If you’re currently drawing 10 mA in sleep mode, then you’ll have about 3 weeks of battery life if all this does is sleep. Any actual motion sensing and communications will decrease this, possibly substantially. Do you have any battery life requirements? – Dave Sep 22 ’13 at 1:50

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Battery powered device hardware design tips

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