In this video, I'm going to talk about how to replace the battery inside an Android tablet
with a power supply. Now there's a bunch of reasons why you'd want to do that. The first
is that if you are using a tablet -- or some other device like a phone -- and it's always on,
it might swell the battery with age. Now this is a particularly a problem with Android. The
Android operating system still doesn't have Smart Charging. The Samsung devices do, but Android's
global OS does not. What that means is that without Smart Charging, any Android device that's
plugged in all the time is going to have a battery that degrades kind of quickly. So in this video,
I'm going to talk about how you can fix that. Now we learned this at Decent Espresso kind
of the hard way, which is we ship out a tablet with each of our espresso machines. And in about
a year of switching to much nicer tablets, we've had to replace about a third of them.
It's part of our warranty, so the customer doesn't lose, but, you know, we lose. So we really wanted
to dive in. And we also don't really like both the financial waste of throwing those tablets out,
and the electronic waste of throwing them out. in this video I'm going to talk about how you replace
the battery in this. Now, first -- why do these batteries swell at all? Now it turns out that a
battery has an electrolyte in it, and when that battery is hot or charging, the electrolyte is
degrading. And when it degrades to a certain point, gases get released. Those gases then
cause the battery to swell. Now that causes all sorts of problems. When they swell, you probably
should stop using the device. Because it can cause leakage, and shortages, and hot spots. And that
swelling is actually what causes batteries to catch fire. So if your battery is swelling, you
really want to address it either by getting a new battery or getting rid of the battery completely.
So you can recover a tablet that's badly swollen and get it back to a usable -- almost
new -- state. There are a few different ways to avoid this problem in the first place. Now
the best one is if you're using an operating system that's fixed this. That would be either
an Apple device -- the current ones, old Apple devices had this problem. Or a Samsung tablet,
or a tablet with firmware that specifically has addressed this and now our current tablets that
we get from Teclast have firmware that addresses this problem, and addresses it the same way that
Samsung does. And that's namely that as the battery starts getting more charged -- in
our case, at 55 percent -- the voltage starts decreasing. So that the battery is much less hot,
and it's charged very gently. You might find that it takes 10 or even 12 hours to go from 80 percent
to 100 percent charge, because the battery is being so weakly charged at that point. Now that
is exactly the same thing that Samsung is doing. You can tell if your Android tablet is doing this
Smart charging by downloading an app that shows you the charge voltage. The instantaneous charge
voltage, when you're on low battery --say 20 or 30 percent -- if you don't have any protection,
that voltage will stay continuous even as you approach 100 percent. If you have Smart charging,
that voltage will decrease. It might only be 0.2.3 or even 0.4 volts, but you will see a steady
decrease in charge voltage. Now the reason they work that way as opposed to turning the voltage
off is that they keep the battery charging, but so gently as it doesn't really matter. Now there's
another way to solve this problem, and that's to have an app on your tablet which is talking
to the USB charger. That's the solution I came up with for this tablet here. What we did is we
changed the firmware so that the USB charger here can be turned on or off with a Bluetooth command.
And then I wrote it into the Decent Espresso app so that as the charge goes over 65 percent,
the USB charger turns off automatically, letting the tablet go back down to 55 percent. At which
point the charger goes back on so the tablet is oscillating between 55 and 65 percent charge.
There is a device out there called "Chargie," which is super cool. It is an app that runs
on your Android and a little USB dongle. It goes between your USB cable and your USB charger, and
it does pretty much the same thing that my tablet app does. Except that my tablet app only runs for
a Decent Espresso machine, whereas Chargie works for any use of an always-on tablet. This is a
Teclast tablet that has already been converted. Now it looks completely normal. This is the tablet
now that we've opened it. Okay, and you can see there's this big battery that's been taped down.
We've made a separate video showing you how to exactly replace this battery with the charge
circuit. And I'm not going to go over everything, because that does it in much greater detail.
However, I want to show you what the tablet looks like once you've converted it. And you'll see it's
largely empty. So what we've got here is a tablet that's now largely empty where the battery used to
sit -- here -- we have this tiny little circuit board. And the circuit board has a cable that
then connects up -- here -- and that's supplying power to the tablet. This yellow cable is tapped
into a place on the tablet that is supplying 5 volts. That's coming in off the USB power -- here.
Now, we've already figured out a really good place to solder that onto. And that video that I'm going
to point you to shows you where to solder. But if you are trying this with a different tablet,
you can absolutely buy our kit, which will have this PC board -- here -- and two tools. You'll
have to use a Multimeter to sense around your tablet to try and find where five volts exists.
The way that this thing works is a little bit tricky, because there are four wires here. Two
of the wires are live, and two of the wires are ground. The tablet sends and receives the battery
state and charger on the same two wires. And the way these chargers work is they pulse. So the
tablet, if it were charging the battery, would send a pulse to the battery, turn it off, and
then suck a little bit of power off the battery to see how charged it is. And then pulse again.
So that is the reason why you can't directly connect the USB power directly to the
battery -- is that the tablet has a charge circuit in it that's pulsing how much charge is there:
"okay, charge again." And so this little PC board here has a capacitor in it that holds the charge,
and essentially fakes a battery. So power goes into the PC board, it holds it, and when the
power is cut off, the capacitor discharges as if a battery were there at a hundred percent. And this
thing then -- the tablet -- is thinking "oh, I've got a battery and it's at 100 percent, so isn't
that nice." This PC board takes the 5 volts that comes in on the yellow cable and then it outputs
4.2 volts, which is what a battery outputs. So the tablet is actually running on 4.2 volts,
not 5 volts. This is the kit we send you. It's super low cost. If you have a Decent Espresso
machine and you're having any sort of tablet issue -- a bubble or swelling -- please let
us know. We will send you one of these kits for free. Or if you prefer not to do the job yourself,
just let us know. We'll send you a new tablet, and you can send us your tablet
to us. And we will do this. So that way we'll be able to essentially upcycle your now-dead
tablet and make it work. Let me go through the parts in this kit. There is this big thing,
and a much smaller sort of guitar-pick thing. Now these are used to pry parts of the tablet open.
And then finally, the most interesting part is this little circuit.
Now this little circuit is the power supply. This cable on the end is essentially faking a battery.
And then this yellow wire is going to connect somewhere on your PC board where there's five
volts. If you have a Teclast tablet, we'll show you in the video. If you don't have a Tecclast
tablet, once again use a Multimeter and find 5 volts that you can solder to. So you're just going
to take your battery out, glue this in, solder this to 5 volts, plug this into your battery,
and then close it. And now you will have a tablet that runs completely without a battery.
This is a tablet made by PIPO. It's an 8-inch tablet. It comes in Android 5.1 and eight
versions and for the first five years of Decent Espresso's life, that's what came on this machine.
Now because the Decent is always keeping the tablet on full charge, and Android doesn't have
Smart charging, these batteries do die after three, four, five years. Sometimes as little
as two. But usually three to five years. And when that happens, we have been simply replacing the
tablets. Or you go and buy a new one. Now it turns out that we can take the battery out of the loop
and just wire them directly into USB, and bring them new life. So the battery-free kit that we
make for the Teclast tablets also works fine for the PIPO tablets. Just a little bit differently.
And in this video, I'm going to explain how to do that. So here is the inside of the tablet.
Now what I've done here is I've put the power supply here. We've left the battery in.
I've got the wires that were originally from the battery, they've been cut. And they've been taped
down so they don't short. That's rather important, because if you let the battery terminals short,
that could cause this to heat up and potentially have a problem. The red and black wires have been
soldered here on some terminals. And the yellow wire, which is the 5 volts,
has been soldered onto another terminal. This wire that's here is the Wi-Fi antenna, and is not
part of all this. You're going to put the power supply here, on this empty space. The red and
black wires are going to go on the ends of here, where it says "plus" and "minus" on the ends here.
You're going to tape down the battery terminals. And the yellow cable is going to go to the last
pin of this little IC here on the upper part. So this here is the power supply that's going to fake
being a battery. And there is, as you can see, a red and a black terminal there and a yellow. Now
those already come soldered on. And if we follow the red and black wires, you will find they end
up here. And this you will have to solder on. So you're going to put one red on the end here,
and one black on the end here. The other part you'll need to solder is a little trickier.
There's this little IC here with six pins. And you're going to solder it on the far right one,
there. Okay? And that's five volts going in. And here's a close-up of having cut the battery
terminals. Those are the wires that come from the battery. I've just cut and taped them down.
It's also a good idea, because this power supply has a little bit of height to it, to put it in
this area here that's a bit lower and unused. And once you've done that, you're then going to take
this case, clamp it shut, plug it into USB, and your tablet will now work on USB power. And the
battery will just be ignored. And hopefully you'll have many years of happy usage of your
now hacked-and-no-more-battery use PIPO tablets. [Music]