How to rebuild a Li-Ion battery pack - page 1/4
How to rebuild a Li-Ion battery pack
Implemented for Fujitsu - Siemens Lifebook S-Series FPCBP25 battery pack source: Electronics-Lab.com
Warning If you are not completely sure what you are doing, don't apply what is described below. In any case www.electronics-lab.com does not haveany responsibility in any way to the consequences that this guide may have. Read it at your own risk. Please don't continue reading if you don't agree with the above.
Did you recently notice poor performance of your notebook Li-Ion battery?. Don't be taken aback, this is happening even to the best battery! Now days Li-Ion batteries are widely used in portable devices due to thereexcellent energy to weight ratio and for the reason they are not suffering from "memory effect". These two reasons make them the best choice on portable devices, but not suffering from "memory effect" doesn't mean it will last for ever! Chemical conversions inside the battery make it to produce electric energy but these chemical reactions aim to attenuate as time and charge cycles pass over. Whenthe battery life drops significantly it's time to search for a replacement, but you will recently find out that most of notebook batteries cost almost 1/3 to 1/2 the price of the laptop at the time you will need to replace the battery. So if you want to keep your laptop but don't want to spend much money for battery replacement it's time to think about rebuild it your own, replacing each individualcell inside the pack. But before step on this you must consider many parameters messing around Li-Ion batteries, about the way they are charged and the way you must handle them.
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How to rebuild a Li-Ion battery pack
Special precautions must be taken to avoid Li-Ion battery fire up orexplosion that can cause serious injuries. This is because Lithium when comes in contact with air burns violently. In this article we will discuss how to handle Li-Ion batteries to avoid any malfunction, the precautions you must take, the way Li-Ion batteries are charged, the protection circuits used and finally you can find a step by step guide on how to reconstruct a Fujitsu - Siemens LifebookS-Series FPCBP25 battery pack. This guide can also be read as a tutorial on how to rebuild other kind of Li-Ion battery packs except the one we will use here.
It's recommended to read the following details in order to understand how a Li-Ion battery must be handled to avoid any injury, before proceed to the reconstruction of the pack.
Overview Li-Ion (and Li-Po) batteries are leading edgebattery technology and consists ideal selection in use on portable computers and cellular phones due to their high energy density and high voltage. A typical Li-Ion cell is rated at 3,6V and this is three times more than the typical NiCd or NiMH cell voltage (1,2V).
Structure Li-Ion cell has a tree layer structure. A positive electrode plate (made with Lithium Cobalt oxide - cathode), a negativeelectrode plate (made with specialty carbon - anode) and a separator layer. Inside the battery also exists a electrolyte which is a lithium salt in an organic solvent. Li-Ion is also equipped with a variety of safety measures and protective electronics and/or fuses to prevent reverse polarity, over voltage and over heating and also have a pressure release valve and a safety vent to prevent batteryfrom burst.
Never short circuit, reverse polarity, disassemble, damage or heat over 100 degrees Celsius a Li-Ion cell. That can be really dangerous.
Lithium battery uses lithium cobalt oxide as positive electrode - cathode - and a high crystallized special carbon as negative electrode - anode. Also an organic solvent specialized to be used with the specific carbon works...