I need to know why my battery is not working properly, how can I fix my battery? The problem I am having is that get fully charge in around 15 minutes and the battery discharge in 4 minutes. When is fully charge and I unplug it, the battery icon shows fully charge with a blue color, as happen when battery was working ok, then after 4 minutes shows that the battery does not have any charge.

The fact the battery shows fully charged means nothing, the symptom is a defective battery.

There is usually a method such as holding the on button for a longer period of time. If it is easy to do the other thing that I've found with all sorts of "smart" devices which turn "not-so-smart" is to remove the battery for a minute or so, then put it back in. Many times the unit will turn on as soon as the battery is reinstalled and work correctly again after that. Last ditch effort, unless someone knows about the Galaxy, is a hard reset, there may be a reset button somewhere on the unit, I don't think the Galaxy has a reset button. If the unit still does not turn on it may need servicing.
1. Try the on button for 15 - 20 seconds if you know it is charged
2. Try charging for an hour or two then the 15-20 second hold on button, #1 above.
3. Removed battery (I'd measure the battery voltage while I have it out) wait ~1 - 2 minutes & reinstall the battery. If it doesn't turn on by itself try #1.
4. Nothing works start a service ticket with Samsung, URL:
http://support-us.samsung.com
You might try searching there as well for an answer to see if there's anything I missed.

Could be it needs to be reset. With Kindle turned off, push power button and hold for 15 seconds. This will reboot it to its default settings and usually fixes problems. If it doesn't help, check to make sure the charging cord doesn't have a short it it. You can check it by plugging it into the kindle and watch the charging icon on top right. If it it shows no charging while wiggling the cord around then the cord could be bad. If not you would need to replace the battery.

Your tablet may need its battery calibrating. To do this run your tablet until it turns itself off, this will ensure that there is no charge left in the battery. Then leave it on charge until the battery is full. Normal battery use on modern devices like tablets and phones should be between 25-75%, with a calibration once every 3-6 months to ensure a good battery lifespan. If this solution does not work you may need to replace the battery.

new electronic devices often have instructions that they need to be fully recharged after bringing them home from the store, if you failed to fully charge them , then used the device until battery is drained , you may need to recharge it for a full 16-24 hours before being able to reuse them, read brochure and manuals for proper charging instructions, if this fails you may have faulty battery, charger or the unit itself is faulty, send it back to the store.

The battery connector in the Nexus 7 (2012 model) is notoriously problematic. Sometimes dropping the device can cause issues that prevent the Nexus 7 from charging altogether. A hard reset may not work. Fortunately, it is quite easy to fix.

However this will void your warranty.

Pop the back of the Nexus 7 case open by pushing a credit card or guitar pick or small screwdriver under the edge of the black plastic case. Start from the top and gently pry the case open, working your way around. The back of the case will come off quite easily. The battery occupies the bulk of the left-hand side of the unit, and a group of six wires come out of the top of the battery to a connector on the circuit board. Gently push the plug out of the socket connector, wait 15 seconds, and push it back in. Snap the case back on and plug in your charger. You should now see the battery charge image appear.

In my experience, the Nook lithium ion batteries are very sensitive to over-charging. If you are still under warranty (1-year manufacturer. Call 800-thebook if you're not sure and they will let you know), replace the device. In the future, do not leave the fully charged device plugged-in while you're using it. The inability to fully or quickly charge the battery is the first step before swelling of the battery like a balloon. I'm not kidding. Fortunately, the B&N customer service is pretty helpful.

I think you need a new battery.