Permanent battery + USB connection for Tablet
I am new here and wasn't sure where to place this post. If Admins believe Hacks or Usage sections to be more appropriate for it - please move the post.
Now to the point:
I've got two Samsung Galaxy Tab 7.0 tablets - old one and a new one.
I keep them employed for up to 10 hours a day. The obvious problem is battery - it doesn't last long enough under heavy load.
The simplest solution is, of course, to keep them constantly plugged-in to the charger.
The catch - I need them connected to the USB at all times (primarily for development and wired resource management).
USB port provides only 500mA, so they don't charge - they just discharge a little slower than when unplugged.
It is incredibly inefficient to disconnect the device from USB, charge it, and connect it again.
Therefore – I’d like to hack it a little. Or mod it, if it's a better word. I’m not concerned with hardware warranty, at this point (I’ll be experimenting on the old one first, and it’s long past its prime).
What I need:
I want to have the device operating 24/7, constantly connected both to the charger and to the USB port on my PC.
How I imagine doing it:
I take two USB cables. I connect one (A cable) normally to PC USB and to the tablet. I cut the second cable (B cable), remove the tablet plug. I connect the wires from the B cable directly to the battery wires, and plug the other end of the B cable to the charger – this way the battery is always being charged directly from the charger, and tablet port is used for USB connection.
Doubts and questions:
1) Will it work? Has anyone tried anything like it?
2) What is the blue wire running from the battery for? Is it for the thermistor? Do I need to worry about it at all?
3) There are two black wires, two red ones. Which ones should I connect the respective battery charger's wires to? To all or just some set of two of them?
Link to the picture of the insides: http://4.bp.blogspot.com/_ZKlSQm2j7T...-56-29_495.jpg
4) Better yet – can I simply dump the battery and connect the charger directly to the battery socket wires?
I’m quite determined to go ahead with it, and I could use any help and advice you may have for me. Also, I’d like not to kill the tablet, or myself for that matter.
Any guidance is very welcome.
11-15-2012 01:16 PM
the samsung batt. is in parallel, if you can charge on usb, you are running 4.7v.
use a regulated 5V DC external power supply and solder it on any of the black terminal the same on the positive side.
using the charger is a bad idea, you need the same or higher amphere as your battery.
you are right, the blue one is the thermal sensor which stops the battery from over cooking =)