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Make your own 3000mAH battery

Quatermass

Quatermass

Newbie
If you want a cheap way to make yourself a large external battery here is how to do it.
Go to Maplin shop, buy a pp3 clip, a 4xC battery holder and 4xC rechargeable batteries.
Buy a 2.5mm mono inline socket.

Get yourself a Rolson emergency charger cheap from Amazon. I've seen these on sale from 99p. This comes with lots of different cables including a micro-usb to 2.5mm plug.
Maplin sells these too. But they now cost
 
Sorry,
but we are now in Year 2011.

Emergency chargers with Lipo technology with solar power support, etc...

Best regards.
 
modlar said:
Sorry,
but we are now in Year 2011.

Emergency chargers with Lipo technology with solar power support, etc...

Best regards.
Click to expand...

Being able to do things by yourself is an important quality every man should possess. Unfortunately, these days, too many people rely on others for most things in life (how many people can't even change the oil in their car themselves?). How far do you think you'll make it if society suddenly collapsed (war, etc)? While the world going to hell might not be likely in the near future, the fact remains that it is ridiculously foolish to mock such skills and knowledge. Who knows, you might also even save some money if you really need to.

While this may not be the best solution for everybody, it certainly is interesting. In the long run, knowing how to do things yourself will get you much further than money alone will.
 
MSPreacher said:
Being able to do things by yourself is an important quality every man should possess. Unfortunately, these days, too many people rely on others for most things in life (how many people can't even change the oil in their car themselves?). How far do you think you'll make it if society suddenly collapsed (war, etc)? While the world going to hell might not be likely in the near future, the fact remains that it is ridiculously foolish to mock such skills and knowledge. Who knows, you might also even save some money if you really need to.

While this may not be the best solution for everybody, it certainly is interesting. In the long run, knowing how to do things yourself will get you much further than money alone will.
Click to expand...

I agree with you man, but I guess you went too far to prove your point. I mean why would I change my engine oil in post-apocalyptic world when I dunno everything is destroyed?
You are right and what you have shown is a great DIY project. Totally agreed.
 
modlar said:
Sorry,
but we are now in Year 2011.

Emergency chargers with Lipo technology with solar power support, etc...

Best regards.
Click to expand...

Hm never heard of Lipo technology. Is that something to do with this web site? :p

Sure if you can afford to spend lots of money then you don't need a cheap option. Maybe you live in a country where there is lots of sunshine every day. Some of us on this planet don't.

Being an Engineer myself I always consider making something rather than buying it first.

When your expensive Lithium-ion polymer battery in your solar power pack wears out in 3 years time, no doubt you'll throw out the whole device and buy another one. Me, I'll just replace the internal battery.

I guess I'd survive in a Zombie Apocalypse, and you'd be a nameless Zombie perhaps? :)

Take great care.
 
Quatermass,
I understand Your situation.
But, do not worry.
Beside I am Tech freak and developer of NANO technologies, I am also
certified donator.
Almost every month I donate also for children from undeveloped countries and for poor people as well.
So, your reaction (Zombies..) is out of kind, polite communication.
Maybe, with a little help from us, donators, can also You sometimes buy on ebay, a modern charger for 9 $.
Oh, Your "emergency charger" was not much cheaper, agree? So, here we have personal problem...which can not be solved with my donations.

Best regards from the sunny side of this wonderfull planet.
 
I too have that engineering streak. Loving to take things apart to see how they work.
There's a sense of accomplishment that comes from making something yourself, which can be adjusted to your own spec!

Thanks for the info!
 
Well Done!
I like the idea. from what i can see you've hooked a few batteries (rechargeable), in series, connected a jack, to which you connect the mini USB charger cable, and that's it?

What about voltages, amperage etc. I didn't quite get the 5.3v thing you mentioned?

What I'm going to do differently is to take the and old usb (female) connector so as to use the normal supplied USB PC cable to charge. What do you think?

If anything, this has got to be the biggest flaw HTC has had, for some time now. I've had MANY HTC's and the newer generation is seriously bad when you talking battery life. (How do they get iPod's to run for so long???).
PS: I'm not an Electrical Engineer...
 
Each rechargeable battery is 1.2V therefore 4 of them connected in series comes to 4.8V.
Ni-MH batteries give off a stable constant voltage until they become exhausted (unlike alkaline which start at 1.5-1.7V (lithium AA/AAA starts at ~2.0V) and starts to drop as soon as you use them. An alkaline is deemed to be exhausted when its voltage drops to 0.9V which is far too low to power a phone even when 4 batteries are used).



The USB spec on voltage says it can be 5V +- 0.5V so 4.8V is well within what is allowed.

Sure use a female connector, you may wish to add a small 150ohm resistor across the D+, D- pins as this is the new configuration to allow future USB powered devices to detect chargers.

Regarding current. C batteries are around 3000mAH capacity, AA are ~2200mAH and AAA at ~1000mAH so choose any Ni-Mh type you like.
All these numbers mean is that a 3000mAH battery can be used to drain 3A over an hour, or 1.5A for 2 hours, etc. They say '3000mA' instead of 3A cause it sounds bigger!

Note: when adding batteries in series, the individual voltages add up. But the amperage capacity doesn't. It remains constant.

My standard HTC battery is 1200mA and lasts for ~9 hours.
My 1600mAH Amazon battery lasts for ~16 hours.

The iPod lasts longer because the screen is so much smaller and of course it is not constantly monitoring the airwaves for incoming calls and text. The HTC display eats up ~80% of the battery life followed by the GPS and the various wireless functions.
A typical ipod battery is only ~800mAH.
A iphone battery is typically 1000mAH.

Oops. Did I say 5.3V? I meant 4.8V (4x1.2V). Sorry about that.
A good quality Ni-Mh C battery is capable of giving 1.3V to start off with. Though this soon drops to 1.2V in a couple of minutes.

Footnote:
I did buy recently a very cheap alkaline mobile phone charger from Asda (Walmart) for
 
Quatermass, very nice.

First thing I learned in boot camp was
 

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Excuse my ignorance, Although the USB spec is 5.0v +/- 0.5 isnt that an operational voltage, My basic understanding is that to charge on cell the charging cell needs to be at a higher voltage, what does the Desires battery drop to voltage wise when empty, It wont be much below 5v but with 0 capacity?
 
Jaffa said:
Excuse my ignorance, Although the USB spec is 5.0v +/- 0.5 isnt that an operational voltage, My basic understanding is that to charge on cell the charging cell needs to be at a higher voltage, what does the Desires battery drop to voltage wise when empty, It wont be much below 5v but with 0 capacity?
Click to expand...

The HTC Desire HD battery is 3.7V when fully charged. Lithium ion batteries keep this voltage fairly constantly until near exhaustion.

Modern electronics in a phone probably use 3.3V or lower operational voltages.
 
There are solar chargers now which i will be using if my battery is running out outside. (around $20 to purchase)
 
I bought two $20 ebay solar chargers that claim to have a 2500mah battery in them and to work with the HTC Desire HD.
Both didn't. Their batteries were dead...
:(
You buy cheap, you get crxp.
 
2bashy said:
Lol...are you serious???
Click to expand...

Of course I am.

It works very well.

I can recharge virtually anything that needs 5V as I made the end interchangeable with microUSB, mini-USB, etc.

I tried buying two cheap solar powered 2000mAH rechargeable packs from ebay but neither worked even after getting replacements.
Looked to me that the Li-ion batteries were 2 years old when I got it supposingly as new. So basically old stock someone tried to pass on.

Also unlike the commercial rechargers with their own batteries, this one doesn't self-discharge after a few months.

Of course nothing to stop anyone from making it with AAA, AA or D Ni-MH batteries if they want it to be smaller (with less power) or even more power.

Sure it looks ugly, but it works. Plus when the batteries start to go in a few years time. I can simply buy off-the-shelf replacement cells and not an entire new unit!
 
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