How to change battery in Tablet (English)

Now on the market you can almost always find batteries for your specific model, but there are situations when you do not find your battery or its price will be high. I’ll show you how to get out of the situation, if you’re unlucky.



Here you will learn how to successfully change battery in Tablet regardless of the model and manufacturer.

This store sells universal Li-pol batteries. Aliexpress.com  — is the largest Chinese marketplace. Delivery of goods worldwide. There is a system of insurance against bad sellers, as on E-bay.

To find a suitable battery, first you need to disassemble the Tablet, measure the dimensions of the old battery and know its voltage.

For disassembly of the Tablet we might need a small Phillips screwdriver and old plastic credit card. Screwdriver for servants would, if they exist. And card to pry off and disconnect the rear cover.  Card leaves no opening marks on the body as opposed to a knife or flat head screwdriver. If you have no experience on Youtube.com, type in search: Tablet model with the word «Repair» or «expand. So you can see how others do. If no video with your model, you can see how it happens on another Tablet like parsing example.

After parsing the Tablet dimensions measure the old battery. We need length, width and thickness of the battery. Sometimes it happens that the old battery takes no more free space in the tablet. The measurements it is desirable to bear in mind the free space because you can install the new battery, the larger and consequently more capacious.

Next, we need to determine the voltage of the old battery. It is desirable to have a new battery voltage does not differ from the old one. If it will be different at ± 0.1 V. Typically, the battery voltage is 3.7 tablets or 7.4 If voltage is not indicated on the old battery and you don’t have a multimeter, you can look at the power supply included with the digitizer. There is a label on the block. If you specify output voltage 5V, voltage battery 3, 7V. If the voltage on the power supply is greater than 7, 4V, battery voltage 7.4 V.

With regard to the capacity of the old battery, you can learn from the characteristics of the Tablet (usually this parameter indicate producers) or on the label on the battery. New battery selection rule is that the bigger the tank, the better, because the tablet will work longer.It is desirable that the new battery was no less the old capacity. Capacity is measured in mAh. It happens that they write not mAh and the Wh. To get mAh of Wh, to follow suit: 14.8 Wh (power)/3.7 V (voltage) * 1000 = 4000 mAh (capacity).

And most.  Don’t pay attention to the difference in the number of contacts between the old and new batteries, if it exists. Generic batteries usually 2 contact. On the old battery in the tablet can be 2 or more contacts. Especially a lot of wires from battery to branded tablets. For example, on the old battery 5 contacts on the new 2.  How to connect a new battery in that case, I’ll write below.

Now select and order a new battery, on the basis of these rules and parameters. The Tablet you can collect and use until you receive an order with a new battery.

Well, you got a new battery.

Now disassemble the tablet.

Look carefully as fastened our old battery. Usually batteries krepjat on double-sided tape. To gently loosen the old battery, you can gently heat it up to 40-50 degrees Celsius in the usual hair dryer.

Attention: do not overdo it with heat, as can overheat the matrix, leading to its deterioration.

Typically the battery is glued directly onto the matrix. Well, if a matrix has a metal back cover, but it also happens that the back cover is missing and her role is immediately mirrored film matrix. This film is based on glue and can be removed from the battery which when the matrix itself or shift. If this happens, then it will be necessary to put this film gently into place, without matrix damage, damage film and dirt between the film and the matrix. You may need to remove the motherboard. To avoid this, try gently with a hair dryer and hold the tape at the time of removal of the battery. Personally I loose batteries bank credit card, put her slowly into place gluing, and at the same time gently pull the battery.

If you don’t know how to solder, then make the connection using a bundle of wires, but I recommend to solder. To cut with a twisting the wires from the old battery, remove them and screw the peeled wires of the new battery. Then place twisting good  duct tape or adhesive tape.

If you solder, respectively should look what the wire connection to the old battery to the motherboard. If there is a connector, it is better to cut the wires with a margin and soldered to them. If soldering directly goes to the motherboard, then it is better to connect the new battery to the Board directly.

It is necessary to connect the Red wire to the Red (a plus), and black to black (it is minus). It happens that the manufacturers duplicate the wires and then maybe two red and two black contact. In this case, simply connect them together to the desired color.

It happens that the old battery is additional wires. For example, yellow or white. And we ordered the battery with only two contacts. Then it is necessary to do the following. The old battery must pull a charge controller. It is a thin Board that is mounted under the duct tape on the output side the side wires. Here we remember where the plus and minus fastens old cell battery. Cut the contacts from the old controller cell battery and podpaivaem directly to the new battery, strictly observing the polarity. In this case we get dual controller, but to work the Tablet is almost not affected. Here’s my example of the battery connection plate.



You can, of course, disassemble and replace the new battery charge controller with him from the old. But in this case, you need to be a guru, because solder cannot overheat Bank Li-po battery. In production we use high speed welding, which gives no overheating of the cell.If will be sweat soldering process should last for 1 second.

Attention! When you connect a new battery cannot damage or deform the battery battery film. Can spoil the new battery.

Is there another way to connect the battery. For example, we have 2 battery with a capacity of 3500 mAh 3.7 v volts. We can make a choice of them conditionally one battery with a capacity of 7000 mAh 3.7 volts or voltage battery 3500 mAh, but with voltage 7.4 volts. To sum the capacitance connect the batteries in parallel. To summarize voltage connect the batteries in series. Sometimes this method you need to optimally pick and make the replacement battery into the tablet.



Once connected, carefully isolated all duct tape or adhesive tape and stick the new battery by using double-sided tape in its place.

Turn on your tablet, check the charge level, try to recharge it briefly. And if all is well, then collect your tablet.

To the battery, it is necessary to more effectively work will make its calibration. For this purpose it is necessary to do a complete charge/discharge cycle.

Thank you for your attention.

Successful replacement of the battery!