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Galaxy D III Samsung cell phone battery pack Answered

I have a Samsung Galaxy S III cell phone with the original battery.

It does not last near as long as i want it to.

I can buy a better battery pack... but why?

I found this ad for batteries.  Why not hook them in parrallel and have a decent, log lasting backup?

I just need some instructions before I trash a perfectly good smart phone....

Product Description:

Brand new and high quality.
 Standard voltage is 3.7V, the voltage of full charge & empty condition is 4.2v & 2.5v respectively
Particularly suitable for flashlight, electric tools, electric bicycles, electric vehicles
Capacity: 5000mAh
Voltage: 3.7V
Material: Li-ion
Dimension: 65 mm (H)x 26 mm (Dia)

Package Includes:
2 X 26650 3.7V 5000mah Battery

I already have a charger for these batteries.


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7 years ago

That phone has a built in internal battery. To change it out you would need to pull the phone apart.

Now if you want to build a battery pack to plug into the phone through the USB plug then go for it. Just make sure you have a charger for the batteries. If you use more than one in parallel make sure they can be separated so they can be placed into the charger one at a time. You won't be able to charge them while they are still wired together. Just keep in mind that the phone will not charge or recognize the battery pack unless it's putting out at least 5V @ 500mA. So the batteries you've mentioned would not work in parallel. They would have to be wired in series giving you a total of 7.4V. This would need to be connected to a 5V regulator like an LN7805 so you'll have the right output for the phone.


Reply 7 years ago

I have a 5600mAH replacement battery with extended back.

Sometimes we spend more than a few days without power and this would be a backup type thing.

Thanks! I am smarter now.


Reply 7 years ago

Check the technology side of the site. You will find a great many USB charger projects. From there i'm sure you can get some ideas for creating a good backup battery system that can use solar panels to help recharge the battery pack.