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Accessories Interesting back up battery

brettlewis

Android Expert
Nov 3, 2009
862
49
Arizona
I was one amazon buying a new usb charger since my dog ate mine :(, and whil searching, I happend uppon this

Emergency AA Battery Charge Extender for the Motorola DROID

It uses 4 AA batterys to chage your phone, seems like an pretty interesting way to charge in case of emergancy. I wouldn't mind keeping one of these in my car, or taking it while traveling for extended periods of time.

pretty neat. Got any other cool ways to charge?
 
I'm all over Powermat when they make the Droid battery (not out till Fall unfortunately). For those that don't know, it's just a mat you set your device on and it charges without wires. The regular mat has room for 3 devices I think. Been out for a bit, but you had to put an add on type case around your phone for it to work. They are now producing batteries with the stuff built in. Pretty awesome...

Powermat USA | Wireless charging mats and receivers for your iPhone, iPod, BlackBerry and other devices
 
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Actually, yestday I saw an advertisment for "Duracell myGrid" it is just like power mat, but cheaper.
it works with the droid NOW (I think)!
it has different attachments for different charging interfaces, and im pretty sure it works with droid.

Amazon.com: Duracell myGrid Cell Phone Starter Kit: Health & Personal Care




(i may be wrong about working with the droid, but it says "motorola phones" and I think Motorola uses micro usb as a standard.)
 
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I was one amazon buying a new usb charger since my dog ate mine :(, and whil searching, I happend uppon this

Emergency AA Battery Charge Extender for the Motorola DROID

It uses 4 AA batterys to chage your phone, seems like an pretty interesting way to charge in case of emergancy. I wouldn't mind keeping one of these in my car, or taking it while traveling for extended periods of time.

pretty neat. Got any other cool ways to charge?


Back to the initial topic ... Has anyone used this? How much charge do you think you will get out of 4 AA batteries?
 
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doubt it, this is wire-free induction technology, no?

Hey Quad .. yes .. it's wire free. But you have to do two things to make a powermat work efficiently.

Inside the powermat there is a Primary Induction Coil.

So ...
1. There has to be a Secondary (or receiving) coil attached to, or inside the device that is going to be charged. The receiving coil is built specifically to receive the proper amount of electromagnetic energy from the powermat to produce the correct voltage for your device. (also add some tricky capacitors and a resistor or two to keep too much juice from flooding into your device.

2. In order to have efficient charging, the primary (in the mat) and the secondary (in your phone) induction coil must be magnetically aligned. If they are misaligned by even a few degrees, the potency of the incoming charge is decreased significantly.

So the reason I'm fairly certain there will be some sort of special case to snap onto the Droid is:

1. I've seen several pics of the insides of our Droids. I haven't seen anything that looks like an induction coil inside it.
2. We don't have any magnets inside our Droid to properly align the non-existent coil with the mat.
3. The powermat has more technology inside it than just a transformer. It also has an RFID reader that reads the RFID tag of the device that's sitting on top of the mat. That way it knows how to properly interupt the coil to create the proper magnetic field for the secondary coil that is sitting on top of it.

Those three reason above are why they are going to have to do something aftermarket to our Droids to make them work with their system.

I have also heard a lot of complaints from people that the powermat is dreadfully slow, even though they claim in their marketing to charge as fast, if not faster than your wired charger. Considering how fast my Droid charges on the USB cable attached to my PC ... I hardly ever charge it anywhere else.

Hope this info helped!
 
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I was one amazon buying a new usb charger since my dog ate mine :(, and whil searching, I happend uppon this

Emergency AA Battery Charge Extender for the Motorola DROID

It uses 4 AA batterys to chage your phone, seems like an pretty interesting way to charge in case of emergancy. I wouldn't mind keeping one of these in my car, or taking it while traveling for extended periods of time.

pretty neat. Got any other cool ways to charge?

BTW - they sell versions of these at Target, etc., with various connectors to support different phones. I have a standard mini-USB version for my old Blackberry.
 
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Perfect timing. I was just looking at an external battery pack/charger and was coming here to ask a similar question.

I was looking at Battery Adapter PRO

It says ....

Uses just 4 alkaline or rechargeable AA batteries to power your device
Provides up to 5 full recharging cycles for your device​

Here is my question for the way that I plan on using it. I don't want it to be a recharger as much as I just want to use it as an external battery pack.

Let me explain. I do off-road motorcycle rides where I am riding for up to 10 to 12 hours in the desert. I want my phone on all the time running SportsTrackLive so that friends/family can track me (live, real time) on-line.

My thought is to start will a full battery but have this "external battery" plugged in the entire time (this is all in my backpack).

Will the phone run for 6 times longer than usual? The device says it give 5 full charges and when that runs out would the phone switch to the internal battery just like if you unplugged a charger from the wall?

I hope this makes sense and thank you for any information/feedback you can provide.

Brian
 
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Brian -

Thanks for posting that ... very neat! My guess would be that your Droid would just see it as a charger and draw off of it until it dies, then switch to its own internal battery.

Although I have plugged my phone into cigarette lighter plug and the little white charging light on the side doesn't light up. I look at my lock screen and it says "Charged".

At under $20 ... I think it's safe to buy one and try it out. I'm placing an order for one right now.

Take care,
Brad
 
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Hey Quad .. yes .. it's wire free. But you have to do two things to make a powermat work efficiently.

Inside the powermat there is a Primary Induction Coil.

So ...
1. There has to be a Secondary (or receiving) coil attached to, or inside the device that is going to be charged. The receiving coil is built specifically to receive the proper amount of electromagnetic energy from the powermat to produce the correct voltage for your device. (also add some tricky capacitors and a resistor or two to keep too much juice from flooding into your device.

2. In order to have efficient charging, the primary (in the mat) and the secondary (in your phone) induction coil must be magnetically aligned. If they are misaligned by even a few degrees, the potency of the incoming charge is decreased significantly.

So the reason I'm fairly certain there will be some sort of special case to snap onto the Droid is:

1. I've seen several pics of the insides of our Droids. I haven't seen anything that looks like an induction coil inside it.
2. We don't have any magnets inside our Droid to properly align the non-existent coil with the mat.
3. The powermat has more technology inside it than just a transformer. It also has an RFID reader that reads the RFID tag of the device that's sitting on top of the mat. That way it knows how to properly interupt the coil to create the proper magnetic field for the secondary coil that is sitting on top of it.

Those three reason above are why they are going to have to do something aftermarket to our Droids to make them work with their system.

I have also heard a lot of complaints from people that the powermat is dreadfully slow, even though they claim in their marketing to charge as fast, if not faster than your wired charger. Considering how fast my Droid charges on the USB cable attached to my PC ... I hardly ever charge it anywhere else.

Hope this info helped!

That is good information, and may very well ring true. However, when talking to the Powermat rep at CES, then said specifically that the technology would be built INTO the battery, thus not requiring any aftermarket cases/accessories. I guess we will find out sooner or later...

As to the speed argument, that is probably a good one. I really haven't looked into it. I charge my phone every night, so it wouldn't matter for me personally if it takes longer. We have several phones in the family including 2 droids, so just being able to plop them down on the powermat before going to bed would be a nice (not necessary) convenience...

**EDIT**
Found some stories on it from CES. Here is what I am trying to get across...

On the device side, Powermat announced the Powerpack, a battery replacement pack that integrates the inductive technology, obviating the need for an external case. Twelve models of battery packs will be available at launch, supporting phones from HTC, RIM Blackberry, LG, Samsung, Nokia and Sony Ericsson (alas, no iPhone). The Powerpack will be available in the May/June timeframe and should cost between $30 and $40.

Link : http://www.popularmechanics.com/technology/upgrade/4341594.html

Note it doesn't say Motorola, which is why I asked them if they would be making them. As I mentioned above, they will, but not until Fall (versus May/June for other phones)...
 
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...so Inphosys makes a huge backpeddling post to explain induction (whereas he previously stated contact would be necessary), when I already knew how the entire process works. Good show, now step away from the keyboard.

Even though is wireless ... there is still a lot of contact required.

You can't go 20 feet away and expect this thing to work ... heck ... 2 inches away!

also, when I wrote my first post, I wasn't about to explain the basics of induction coils. I figured after you re-posted that I might as well. I'm really sorry for providing useful information in a forum where people like to learn new things. I'll refrain from now on.

Deepest apologies,
Brad
 
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That is good information, and may very well ring true. However, when talking to the Powermat rep at CES, then said specifically that the technology would be built INTO the battery, thus not requiring any aftermarket cases/accessories. I guess we will find out sooner or later...

That's very exciting news. I'll try not to flame you for providing good content that others might learn something from. :D

Edit: I wonder if they will have to make the battery cell smaller to fit the powermat equipment inside. Oh, maybe a new battery door and a larger battery case to keep the cell the same size but include the powermat equipment? Oh who knows! Hey Quad ... you already know "how the process works". Would you explain it to us?
 
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