Every relationship needs a good contact. This happens not in personal love life, but also in elcctronics. So bad contact may screw you 🙂
I just charged my Ni-MH rechargeable batteries yesterday. After over 2 hours charging time, I tried the batteries. But my batteries were still empty. How come? I was so sure that my charger was ok (and I was so sure that my batteries were ok to). Then I decided to check my batteries condition. The temperature was cool enough (should be warm to hot after they were charged). Then I checked the batteries contacts. Well, I found dust and rust there. I see the problem 😉
The picture shown above is my Sony battery. You can see that its surface is filled with dust (fat, rust, etc). This may conduct bad contact with the charger. So the charger can’t flow the current in to the battery. The result is no charging process occured.
The idea is clear and simple. You have to clear those dusts. But with what? Water is not a good solution since they may be a problem for metal contact in long term. The simplest solution is to find a metal polish (shown above is Brasso, I don’t know the brand in your country. a popular WD-40 should do the same I guess). Apply this on a soft fabric and wipe the dust gently from the connector (use extra power when necessary). After you remove the dust, use another clean fabric to clean up the connector.
Picture above is my other battery (which has been cleaned up with technique explained above). You can see shiny connector. Not totally remove the dust and rust I believe but this should be sufficient to make a perfect contact with you charger.
This method will also work for other things like your camcorder battery connector, your cellular phone, your PDA, etc. Remember, bad contact will screw you. So clean them up!