User Comments

Welcome to leave your comments here.

Charge 8 hours?

Many people ask me, should them charge their battery 8 hours first time before use?

I believe this have a historical reason. In old day, the most commonly use rechargeable battery is Ni-MH, this chemical, will allow minor current passing through it even though it is fully charged. This is seem like it have relatively larger internal self leakage from positive to negative.

In those old days, cell phone battery normally contains 3 Ni-MH cell in series to generate 3.6V (1.2V per cell), while notebook battery normally have 8-12 cell those day. Charging it in small current continuously for long enough will eventually balance all the cell, this is good for those cell in series, so all of it fully-charged at the same potential. This is safe as long as the current is small result in no overheat of battery cell.

If all battery cell in good matching of relative state of charge, it will be able to output the maximum power can be stored, which is same with the maximum power of the poorest cell, for example 3 cell in series have capacity 700mAH, 710mAH, 720mAH respectively, but currently it stored 210mAH, 190mAH, 200mAH respectively. When charge to full, cell 1 have 700mAH (700-210=490mAH), cell 2 have 190+490=680mAH, cell 3 have 200+490=690mAH. If not all cell reach fully charged state, the maximum capacity it can reach is only 680mAH, while the poorest cell actually can store 700mAH. If small current is allowed to continuously charge it for long enough, it will eventually reach 700mAH, 710mAH, 720mAH respectively, anymore charge will turn into heat and dissipated into environment.

Why 1 cell is charged 490mAH, all the others is 490mAH additional charge? Because it is in series! Current is same in series. Why it relative state of charge is differ at the beginning? This is the result of some slightly different in each cell property example different in self discharge rate. It is unpractical or even impossible to manufacture all these cell to have zero deviation in their property. It contains some error let say +/-1% from cell to cell.

Ni-MH is very famous those day because it doesn't need special protection circuit. After it fully discharged, it internal resistance will become very large, and the machine will shut down due to the loading effect of the internal resistance, the cell will never fully drain. Even if Ni-MH is overcharged, this will not result in disaster as long as it temperature is within the permitted range.

Later, those Ni-MH was replaced by Li-ion, high energy density cell without memory effect. Li-ion cell in general, will not allow current passing through it after it is fully charged, it internal leakage is relatively small. That mean after the cell reached equal potential with the charger Voltage, no more current will pass through it. Further more, to avoid this and prolong battery life, manufacturer have designed protection circuit that will block the charging after the current reached a very low threshold for example 100mA. Therefore, li-ion battery cell can not be balanced by this way, it must includes complex circuitry in any application that required serious consistency toward relative state of charge of it battery cells.

In conclusion, Li-ion battery do not need 8 hours on the first charge, it serve no purpose. As long as the indicator show 100% or one of it cell fully charged, charger will stop charging the battery.

How to fix a mouse button

Mouse usually malfunction after excessive clicks. The problem usually occur at the left click button since it is pressed most often, other time is the wiring problem at the end closer to the mouse. Shopping for new mouse become hobby to some fellas.

I am also one of the 'victims' to this 'unavoidable' problem, therefore I also have a lot of mouse. Each one last me around 2 years. Wireless mouse nowadays only use one battery cell, I guess there are some sort of charge bump integrated inside the optical chip, it generate the Voltage needed for LED.

Today, the one with nano receiver fail. In fact I like this mouse very much, even if it beyond repair, I guess I will get back the same one. So I have decided to open it up and see what can I do. I used LASER mouse before, all the while people say how accurate is laser mouse. Apart from it invisible light, I really can't sense any differences in term of performance, I guess the error arise from human hand consistency is anyway larger than the error of any optical mouse.

I never realized that get it fixed is just a piece of cake before.

Just cut some fine sand paper into a stripe.

Then rub the metal contact, just 2-3 round is okay, because the oxide layer is very thin, must rub all four side of the contacts.

Measure both the end pin, it should measure zero ohm (my meter have some error, so it measure 2.2ohm). If the contact is poor, it will measured several decade kilo-ohm. This two pin is normally closed, press the button it resistance will become infinity, one of then with the top button on it will be connected to the middle.

After assemble everything back, it work just fine, I am glad I get a good working mouse back.

The End

New Stock!

New stock available, freshly manufacturer, hurry, while stock last! Higher capacity also available, inquiry welcome.

6 months warranty! Quality assured or your money back!

Alternative Battery Enterprise, a very practical alternative approach to let your laptop battery live again, no everywhere you get a brand new notebook battery where it cell is freshly manufactured, some of it may have been manufactured for years, that is why it is cheaper and have no warranty from seller sometime, Order while it is fresh!

*Samsung and Samsung SDI and any other trandemark belong to their repective owners.

Battery Chemical ID

Al-thought someone may deal with Li-ion battery cell everyday, it can be quite confusing what is it chemical of electrode and it property, fortunately, battery university have a quite nice reference for me, share the link so people interested in this can find out their answer. Sometime this do give me some problem which I still try to match some battery cell with it board if I can not change the board's parameter or chemical ID.

Please note that even the same type of chemical, different manufacturer making different type of cell with different charging/discharging track. While impedance tracker chip is as simple as just modify it chemical ID. Linear fitness battery lo prediction method is somehow seem quite difficult to know on some particular battery, especially when what parameter it will load to calculate the battery lo percent is unknown.

Even the same manufacturer produce battery cell that behave differently on differ batch.

Gravitational force and energy

In the movie "The Myth" staring Jackie Chan, introduce us some kind of imaginary meteorite that it 'radiation' can cause object losing it weight or create a zero gravity environment. Movie is movie, the film maker seem to have very limited physic knowledge, as we can see the character motion do not seem to obey Newton third law. What could be so interesting if this kind of meteorite really exist?

Looking at the picture above, if it can be created a line where after pass through the line, gravitational force disappear? It simply mean that, we get 'free' energy out it, by just lifting an object in the zero gravity area (zone Z), and let it fall down at the normal area (zone N). 1 ton object can be easily lift in zone Z even by human being. This actually introduce some kind of perpetual motion machine, because energy mined at zone N is more than enough to lift the object up in zone Z, there are surplus which can be utilized for external purpose other than lifting the object in zone Z!

But in real world, creating an zero gravity area required more energy that the system itself can supply, assume that creating zero gravity is not impossible, to fulfill conservation law of energy. Therefore, if the meteorite as describe do exist, must be because it contain great amount of energy.
Even if there are zero gravity area in the earth, in the real world, human being never see as it is possible to create a very fine boundary where the gravity suddenly disappear, forces interfere and try to become unity. It is possible that the gravitational force gradually disappear, but not suddenly as observed. Therefore, moving from A to B and from C to D may required more energy that the free fall force produce at D to A. This kind of system will not produce any force that can be utilized. Natural Law seem to prevent 'free' energy, energy must come from some kind of reaction, involving flowing of particle or energy of other place, it can only be stored and convert by human being, but we can not create it.

Random