External Tablet Charger

by FireSword

5.3K3111

Intro: External Tablet Charger

Hi Everyone!

I decided to post my little projects here instead of my blog, so that they can reach and help more people. This is my first Instructable.

My friend brought me his tablet. The USB socket was not OK, probably broken by his son. The tablet makes a strange noise when you try to charge it, and my power banks shut down, which shows a bad short circuit somewhere.

The USB plug is so small, that even with a magnifying glass I can't see a thing, everything is hidden, attached to the multilayer board. Hot gun does not help!

So I decided to use a charging board like this http://www.ebay.co.uk/itm/301905672102?_trksid=p20...

STEP 1: Using the Charger Board

The little board on the picture is a USB charging board.

It can charge every single Li-Ion battery.

After you dissassemble the tablet, first solder the board directly to the battery terminals and test it.

ALWAYS use a power bank, because a short circuit can damage your wall adaptor.

After the test is complete (in my case blue light comes on) you can see the time it takes for the battery to get fully charged. Test the tablet, is it working fine.

STEP 2: Finishing the Mod

After you make sure it is working fine, drill a small hole on the tablet case for the board wires.

Then put some hot glue above, and you're ready!

-=DISADVANTAGE=-

The Android/electronics do not detect that the battery is charged, and always show low battery messages.

9 Comments

Stewie18 3 years ago

I have a 7" tablet, I bought in 2012. My charger recently broke down, so I tried wiring up a replacement charger, but when I plugged it in, the tablet stopped charging. The tablet powers up, but won't charge anymore. Did I fry something on the circuit board? And If so, how can I charge the battery? Thank you.

prasathsai24 3 years ago

How long does it take to full charge the battery?How long can you use it?

anthonyls6 7 years ago

like it. simple and good for me since I am a super newbie at all of this. my ladys phone is doing the same thing with part so I'll try this.ty

ironsmiter 7 years ago

I wonder if you put the charge circuit in parallel with the old circuit...

It SHOULD continue to register a charged battery just like normal. If not, perhaps a set of diodes on the charge circuit lines would prevent residual voltage bleeding, and give accurate battery monitoring back? I THINK most tablets monitor actual battery voltage, so should read properly once calibrated with a full charge/discharge/charge cycle. As long as none of the monitoring traces have been damaged.

One of the circuit gurus may have a different opinion. but it is a place to start, if you want to try on the next fix.

FireSword 7 years ago

Thanks for your reply. I thought devices monitor baterry status 0-100% by measuring the voltage - let's say 3,2-4,2V , not sure. Perhaps they don't do exactly that. At first I thought to put the charging in paralell, but I can't see any free metal parts where I can solder. That is the reason I did not fix the original socket.

Besides, if I put it in parallel the short circuit which I observed will stop it from working properly.

ydelaforge 7 years ago

Goodyear idéal son praticable. tanks.