How to Rebuild A Li-ion Battery Pack

Batteries have become some of the most essential things in the world. They are used to different power devices, including mobile phones and other electronic devices.

There are different battery chemistries in the world today. Lithium-ion stands as the best chemistry overall because of its ability to hold more capacity.

But a single cell is not enough to power your laptop. That is why they are made into a battery pack. In essence, a number of cells are put together in series and parallel, making the cell powerful. Even with Li-ion batteries, you still have to create more capacity and voltage, and that is why build battery packs the best way to go.

Is it possible to rebuild a Li-ion battery pack?

Many users most prefer Li-ion batteries because they carry a high energy to weight ratio. But did you notice that even such great batteries can start to perform poorly over time. Perhaps you have noticed this and wondering is happening to them.

Another fantastic reason to use Li-ion batteries is that they don’t suffer the ‘memory effect.’ This is why they can be charged overly and discharged deeply but still works well.

Despite these awesome reasons, Li-Ion batteries don’t last forever. It comes a time they cannot just give you the performance you may be expecting.

Unfortunately, there is nothing much you can do about the chemical reactions inside the battery. They are necessary to produce electric energy, which is what makes them work. However, they begin to attenuate with time. Because of the charge cycles, this degradation leads to decreased performance of the batteries. And that is why you are feeling your device is taking too much.

The battery life can drop so much then you feel it is time to get a new battery. Going to the market to buy a new battery is not very hard, but it not easy either. Due to high demand, the cost for Li-ion batteries has hiked. Even the smallest batteries have gone high by almost 1/3 or ? of the original price. So by the time you are going to replace it, you probably won’t have enough money to get it.

So what should you do? Do you have to keep your laptop away because of this? Well no, there is always something you can do about it.

You rebuild the battery pack. This is a process that is very much possible. It involves replacing each cell inside the pack. Since a battery pack is made of many cells put together, buying individual cells is much more comfortable.

However, it is not something that everyone can do. You need to be completely of what you are getting into. There can be very bad consequences to this process and the resulting product. Anyone who is not careful enough may end up burning their homes to the ground.

How many cells are in a Li-ion battery pack according to different voltage?

The simplest answer is, it depends on the capacity and voltage of the battery. But then, this is where many people get confused. Therefore we can start by looking at different features of a Li-ion cell.

Structure of the cell

There are three layers in a Li-ion battery. The first is the positive electrode plate called the cathode. It is made of lithium cobalt oxide. The second one is the negative electrode plate or the anode, made of carbon. Then there is the separator layer.

There is also an electrolyte. This is simply a lithium salt in an organic solvent.

Beside this construction, there are a number of safety measures that make Li-ion batteries potentially good for consumption. This prevents reverse polarity, over voltage and over-heating. That is why it is not easy to find exploding Li-ion batteries.

Voltage

Voltage is described as the real power of the battery. It is among the most important factors that describe a battery. Voltage is abbreviated as V.

There are three types of voltages:

· The nominal voltage. This is voltage manufactures use to compare their products with others. For lithium-ion batteries, it is 3.6V.

· Charge voltage. At full charge, the battery should have energy of 4.2. This is maximum charge the battery can hold.

· Minimum voltage. When discharged, lithium ion batteries can only go down to specific level. In this case, it is 2.8V. At this point, the battery is said to be at zero percent.

Capacity

Many people confuse battery capacity with voltage. Capacity can just be related to how big the battery is and its measure in milliamp per hour, mAh. For instance, you can get a battery written 1400 mAh. This is the amount of energy the battery discharged hourly.

Capacity and voltage are used to describe the power of a battery pack. When creating the packs, one must consider the power the need.

Therefore, if you are looking for a battery pack of 7.2V, you will need to put two cells together. They are arranged in series and parallel. In such care, the battery pack will be 2S. You can have 3S/4S/5S and much more depending on the capacity.

How do you rebuild a Li-ion battery pack?

Here are simple steps to rebuild the pack:

1.Disassemble. Ensure you have already removed the battery from your device. You will notice it is sealed so use a screwdriver to split between the two covers.

2.Identify the cells. You should see the cells with voltages of 3.7V nominal and 1400mAh. There is a part number on each cell.

3.Find the cells. Now that you know which cells are in the battery, you can go to the shop and buy them. The online realm was full of them, and you can easily find them.

4.Take the battery out. Use a screwdriver to lift the first battery and cut the connectors. Lift carefully the other batteries one by one and cut the connectors and the metallic contact. Pay attention to the final cell because it has a PTC attached on top. Remove the adhesive tapes and put them in a safe distance. Then carefully remove the safety circuit. You will need it again.

5.Replace the cells. You will need a spot-welder to replace the battery connectors one by one. Be careful to avoid short-circuiting. Start by replacing the safety circuit.

Points to note:

· Use moderate heat during spot welding

· If the batteries are at different voltages, apply slow charging until they come to the same level.

· Measure the voltage of your pack and recheck after 24 hours.

And there you have it, a new battery pack with more energy.