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AA batteries as power source

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ytj87
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(Last edited by ytj87; 5th September 2009 at 05:01 PM.)
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Default AA batteries as power source

For extended use of GPS while backpacking, I was looking to make a 4xAA battery pack with USB output. Using NiMH hydrides of 2500mah, we're talking a nominal 10,000mah. Enough for 7 to 8 recharges of a stock battery and 4 or so of an extended cap battery.

I searched the net for examples to follow in my build and found this nice one: http://www.boxwave.com/products/batteryadapter/ and this cheap one: http://www.dealextreme.com/details.dx/sku.15048

Much better, IMO, than the $20 Radio Shack one that's only 650mah: http://www.radioshack.com/product/in...&tab=techSpecs

NiMH AA's peak at about 1.4V and are done around 1.2V. So we're looking at between 4.8V and 5.6V for the pack. No voltage regulation is needed, unlike the 9V-to-USB adapters floating around (which have very little power to offer).
 
JJbdoggg
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here is another good one http://cgi.ebay.co.uk/ENERGIZER-Moto...QQcmdZViewItem it uses 2 aa batteries and is very small and compact. i have 5 of these because they were selling them for 99p in the 99p store
 
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You probably have, but have you thought about the solar battery packs? I've seen small ones, not much bigger than the phone with 3600mah batteries. If the panels exposed while hiking it can charge and then be used later.
 
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but in the winter they become almost useless
 
AdamPI
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Originally Posted by JJbdoggg View Post
but in the winter they become almost useless
What even in Nigeria?

I guess they won't charge as quick, but you can charge them off the mains first and then get what you can from the sun. I'm going to get one myself for the next time my mate drags me off on a fishing trip.
 
JJbdoggg
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What even in Nigeria?

I guess they won't charge as quick, but you can charge them off the mains first and then get what you can from the sun. I'm going to get one myself for the next time my mate drags me off on a fishing trip.
lol the sun would probably break my phone

come to think of it it would come in handy for camping these are some of the ones i am thinking of getting:
http://fwd.five.tv/gadgets/phones/fr...-solar-charger
http://www.paramountzone.com/solar-m...ne-charger.htm
http://www.ethicalsuperstore.com/pro...solar-charger/
http://www.amazon.co.uk/Portable-Loa.../dp/B001BN2FVM
 
Neuuubeh
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Quote:
Originally Posted by ytj87 View Post
Using NiMH hydrides of 2500mah, we're talking a nominal 10,000mah. Enough for 7 to 8 recharges of a stock battery and 4 or so of an extended cap battery.
..
NiMH AA's peak at about 1.4V and are done around 1.2V. So we're looking at between 4.8V and 5.6V for the pack.
You are connecting them in series, hence its not 10 000mah, but 2500mah. . Which is still almost 2x the htc battery anyhow
 
ytj87
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Originally Posted by Neuuubeh View Post
You are connecting them in series, hence its not 10 000mah, but 2500mah. . Which is still almost 2x the htc battery anyhow
Wow, silly oversight. Of course, series makes it 2500mah. Hmm.
 
AdamPI
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Originally Posted by JJbdoggg View Post
lol the sun would probably break my phone

come to think of it it would come in handy for camping these are some of the ones i am thinking of getting:
http://fwd.five.tv/gadgets/phones/fr...-solar-charger
http://www.paramountzone.com/solar-m...ne-charger.htm
http://www.ethicalsuperstore.com/pro...solar-charger/
http://www.amazon.co.uk/Portable-Loa.../dp/B001BN2FVM
I was thinking of getting this one, 0.77W 2600mAh £8.99: http://cgi.ebay.co.uk/Solar-Panel-Ba...d=p3286.c0.m14

This one: http://cgi.ebay.co.uk/Solar-USB-2600...d=p3286.c0.m14 is a little cheaper, but there are at least 4 variations of that one with different specs, which puts me off.

This one is pretty sweet, but £40 is a lot, although it has 4W solar panels.
 
JJbdoggg
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I was thinking of getting this one, 0.77W 2600mAh 8.99: http://cgi.ebay.co.uk/Solar-Panel-Ba...d=p3286.c0.m14

This one: http://cgi.ebay.co.uk/Solar-USB-2600...d=p3286.c0.m14 is a little cheaper, but there are at least 4 variations of that one with different specs, which puts me off.

This one is pretty sweet, but 40 is a lot, although it has 4W solar panels.
i really like the third one but im a bit skeptical because 60% of the things i order from hong kong end up being fake sometimes very good fakes but they are fakes nontheless. If you decide to buy it let me know how it goes

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